Shari R. Lipner, MD, PhD

Practice Gap

Myxoid cysts are among the most common space-occupying lesions involving the nail unit. Their etiology has not been fully elucidated, but these cysts likely form due to leakage of synovial fluid following trauma or chronic wear and tear. They are highly associated with osteoarthritis and typically are found in close proximity to the distal interphalangeal joints.¹ Myxoid cysts often extend into the eponychium, where mechanical stress on the nail matrix may lead to nail dystrophy, most commonly resulting in a longitudinal groove in the nail plate (Figure, A). The presence of multiple myxoid cysts is not uncommon. Differentiation of this lesion from other nodules of the digits, including epidermoid cysts, acquired digital fibrokeratomas, and giant cell tendon sheath tumors often is challenging without a biopsy.

Technique

The normal nail unit transmits light to some extent, and masses may be identified by how easily they transmit light relative to the adjacent skin. Solid tumors of the nail unit, such as acquired digital fibrokeratomas and giant cell tendon sheath tumors, will not transmit light, while myxoid cysts transmit light easily. A dermatoscope can be used to project light from the dorsal digit through the nail unit. The area occupied by the myxoid cyst will appear bright compared to the surrounding skin (Figure, B). Drainage of the lesion using an 18-gauge needle yielded a clear jellylike fluid that was consistent with a myxoid cyst. This technique aids in localizing and characterizing the myxoid cyst for treatment or drainage. Physician assessment of transillumination has been shown to demonstrate clinical accuracy and high intraobserver reliability in differentiating between cystic and solid tumors.²

Practice Implications

Transillumination is a valuable technique that may aid dermatologists in both the diagnosis and subsequent treatment of myxoid cysts. Location is important to consider when choosing a treatment option. Although lower recurrence rates are achieved with nail surgery, permanent nail dystrophy is likely when cysts are in close proximity to the nail matrix.³ When multiple cysts are present, only the largest may be apparent. Transillumination can guide the physician in achieving more accurate and thorough drainage of the cyst contents, negating the need for more costly imaging modalities. Dermatologists may utilize transillumination as a rapid and economical diagnostic method for space-occupying lesions involving the nail unit.

Practice Gap

Myxoid cysts are among the most common space-occupying lesions involving the nail unit. Their etiology has not been fully elucidated, but these cysts likely form due to leakage of synovial fluid following trauma or chronic wear and tear. They are highly associated with osteoarthritis and typically are found in close proximity to the distal interphalangeal joints.¹ Myxoid cysts often extend into the eponychium, where mechanical stress on the nail matrix may lead to nail dystrophy, most commonly resulting in a longitudinal groove in the nail plate (Figure, A). The presence of multiple myxoid cysts is not uncommon. Differentiation of this lesion from other nodules of the digits, including epidermoid cysts, acquired digital fibrokeratomas, and giant cell tendon sheath tumors often is challenging without a biopsy.

Technique

The normal nail unit transmits light to some extent, and masses may be identified by how easily they transmit light relative to the adjacent skin. Solid tumors of the nail unit, such as acquired digital fibrokeratomas and giant cell tendon sheath tumors, will not transmit light, while myxoid cysts transmit light easily. A dermatoscope can be used to project light from the dorsal digit through the nail unit. The area occupied by the myxoid cyst will appear bright compared to the surrounding skin (Figure, B). Drainage of the lesion using an 18-gauge needle yielded a clear jellylike fluid that was consistent with a myxoid cyst. This technique aids in localizing and characterizing the myxoid cyst for treatment or drainage. Physician assessment of transillumination has been shown to demonstrate clinical accuracy and high intraobserver reliability in differentiating between cystic and solid tumors.²

Practice Implications

Transillumination is a valuable technique that may aid dermatologists in both the diagnosis and subsequent treatment of myxoid cysts. Location is important to consider when choosing a treatment option. Although lower recurrence rates are achieved with nail surgery, permanent nail dystrophy is likely when cysts are in close proximity to the nail matrix.³ When multiple cysts are present, only the largest may be apparent. Transillumination can guide the physician in achieving more accurate and thorough drainage of the cyst contents, negating the need for more costly imaging modalities. Dermatologists may utilize transillumination as a rapid and economical diagnostic method for space-occupying lesions involving the nail unit.

Practice Gap

Myxoid cysts are among the most common space-occupying lesions involving the nail unit. Their etiology has not been fully elucidated, but these cysts likely form due to leakage of synovial fluid following trauma or chronic wear and tear. They are highly associated with osteoarthritis and typically are found in close proximity to the distal interphalangeal joints.¹ Myxoid cysts often extend into the eponychium, where mechanical stress on the nail matrix may lead to nail dystrophy, most commonly resulting in a longitudinal groove in the nail plate (Figure, A). The presence of multiple myxoid cysts is not uncommon. Differentiation of this lesion from other nodules of the digits, including epidermoid cysts, acquired digital fibrokeratomas, and giant cell tendon sheath tumors often is challenging without a biopsy.

Technique

The normal nail unit transmits light to some extent, and masses may be identified by how easily they transmit light relative to the adjacent skin. Solid tumors of the nail unit, such as acquired digital fibrokeratomas and giant cell tendon sheath tumors, will not transmit light, while myxoid cysts transmit light easily. A dermatoscope can be used to project light from the dorsal digit through the nail unit. The area occupied by the myxoid cyst will appear bright compared to the surrounding skin (Figure, B). Drainage of the lesion using an 18-gauge needle yielded a clear jellylike fluid that was consistent with a myxoid cyst. This technique aids in localizing and characterizing the myxoid cyst for treatment or drainage. Physician assessment of transillumination has been shown to demonstrate clinical accuracy and high intraobserver reliability in differentiating between cystic and solid tumors.²

Practice Implications

Transillumination is a valuable technique that may aid dermatologists in both the diagnosis and subsequent treatment of myxoid cysts. Location is important to consider when choosing a treatment option. Although lower recurrence rates are achieved with nail surgery, permanent nail dystrophy is likely when cysts are in close proximity to the nail matrix.³ When multiple cysts are present, only the largest may be apparent. Transillumination can guide the physician in achieving more accurate and thorough drainage of the cyst contents, negating the need for more costly imaging modalities. Dermatologists may utilize transillumination as a rapid and economical diagnostic method for space-occupying lesions involving the nail unit.

To the Editor:

We read with great interest the recent Cutis article by Golda et al,¹ “Intraoperative Electrosurgical Smoke During Outpatient Surgery: A Survey of Dermatologic Surgeon and Staff Preferences.” We applaud the growing interest in the topic of dermatologist safety, as there are currently no established guidelines for precautions while performing surgical procedures. In 2018 we conducted a comprehensive review² to characterize the specific risks, hazard reduction strategies available, and current use of surgical smoke safety techniques during surgery among dermatologists, and ultimately recommend guidance based on the current available evidence. To conduct this review, we collected data from 45 manuscripts in the dermatology, surgery, infectious disease, obstetrics, and cancer biology literature. Herein, we summarize key findings.²

Dermatologic surgeons, residents, staff, and patients are exposed to many infectious, inhalational, chemical, and mutagenic hazards when performing procedures that liberate smoke and plume. These risks are commonplace; however, they are particularly notable during ablative laser and laser hair removal procedures, which produce a heavy plume (averaging >100,000 particles/cm³). Brief periods of heavy plume exposure also are commonplace during electrosurgery.

Infectious particles in surgical plume have been extensively studied, and viral transmission has been demonstrated in animal studies. Human papillomavirus transmission appears to be the most prevalent risk. Surgical smoke has been shown to cause acute and chronic inhalational injury in rat and sheep studies.^3-6

Additionally, chemicals with carcinogenic potential are present in surgical smoke and have been described.^7,8 Chemicals in the greatest quantity include hydrocarbons, nitriles, fatty acids, and phenols. Although there have been no human studies on smoke carcinogenesis to date, surgical smoke has been shown to have carcinogenic properties in vitro.

Given these risks—both evidence based and theoretical—we believe that diligent hazard reduction strategies should be employed whenever possible. Surgical masks and high-efficiency particulate air respirators, such as N95 respirator masks, have been well studied and do provide smoke protection. High-efficiency particulate air masks can be worn when possible, especially during procedures that produce heavy plume, though surgical masks are capable of filtering most of the noxious chemicals in surgical smoke. It should be noted that proper fit with minimal air leak is the most important aspect of overall performance.

Smoke evacuators provide another level of protection. The physician should consider the evacuator’s filtration efficiency, capture velocity, and suction strength when evaluating overall performance. Furthermore, the smoke collection tip should be within 2 in of the surgical field to maximize efficacy. Maintenance for smoke evacuation systems should include regular (as defined by manufacturer instructions) flushing of the smoke evacuator lines.

Despite the risks of surgical smoke and the available options of minimizing these risks, the hazards of surgical smoke and the importance of protection are likely underemphasized. Many dermatologic surgeons do not use surgical masks or smoke evacuators in routine practice, according to several survey studies.^9-11

It is important for the dermatologic community to consider effective ways of spreading awareness. We propose that surgical smoke safety be taught early in residency training. Additionally, smoke safety can be implemented into certification examinations. Access to masks and smoke evacuation devices are an important part of dermatology training. Accreditation Council for Graduate Medical Education funds should be appropriated to provide for such resources.

Finally, and perhaps most importantly, continued awareness should be established in the dermatology community via standardized guidelines and periodic updates in the dermatology literature and lectures at local and national conferences. Not until these strategies are implemented will surgical smoke protection be viewed as a necessary and important component of routine practice when performing dermatologic surgical procedures.

To the Editor:

We read with great interest the recent Cutis article by Golda et al,¹ “Intraoperative Electrosurgical Smoke During Outpatient Surgery: A Survey of Dermatologic Surgeon and Staff Preferences.” We applaud the growing interest in the topic of dermatologist safety, as there are currently no established guidelines for precautions while performing surgical procedures. In 2018 we conducted a comprehensive review² to characterize the specific risks, hazard reduction strategies available, and current use of surgical smoke safety techniques during surgery among dermatologists, and ultimately recommend guidance based on the current available evidence. To conduct this review, we collected data from 45 manuscripts in the dermatology, surgery, infectious disease, obstetrics, and cancer biology literature. Herein, we summarize key findings.²

Dermatologic surgeons, residents, staff, and patients are exposed to many infectious, inhalational, chemical, and mutagenic hazards when performing procedures that liberate smoke and plume. These risks are commonplace; however, they are particularly notable during ablative laser and laser hair removal procedures, which produce a heavy plume (averaging >100,000 particles/cm³). Brief periods of heavy plume exposure also are commonplace during electrosurgery.

Infectious particles in surgical plume have been extensively studied, and viral transmission has been demonstrated in animal studies. Human papillomavirus transmission appears to be the most prevalent risk. Surgical smoke has been shown to cause acute and chronic inhalational injury in rat and sheep studies.^3-6

Additionally, chemicals with carcinogenic potential are present in surgical smoke and have been described.^7,8 Chemicals in the greatest quantity include hydrocarbons, nitriles, fatty acids, and phenols. Although there have been no human studies on smoke carcinogenesis to date, surgical smoke has been shown to have carcinogenic properties in vitro.

Given these risks—both evidence based and theoretical—we believe that diligent hazard reduction strategies should be employed whenever possible. Surgical masks and high-efficiency particulate air respirators, such as N95 respirator masks, have been well studied and do provide smoke protection. High-efficiency particulate air masks can be worn when possible, especially during procedures that produce heavy plume, though surgical masks are capable of filtering most of the noxious chemicals in surgical smoke. It should be noted that proper fit with minimal air leak is the most important aspect of overall performance.

Smoke evacuators provide another level of protection. The physician should consider the evacuator’s filtration efficiency, capture velocity, and suction strength when evaluating overall performance. Furthermore, the smoke collection tip should be within 2 in of the surgical field to maximize efficacy. Maintenance for smoke evacuation systems should include regular (as defined by manufacturer instructions) flushing of the smoke evacuator lines.

Despite the risks of surgical smoke and the available options of minimizing these risks, the hazards of surgical smoke and the importance of protection are likely underemphasized. Many dermatologic surgeons do not use surgical masks or smoke evacuators in routine practice, according to several survey studies.^9-11

It is important for the dermatologic community to consider effective ways of spreading awareness. We propose that surgical smoke safety be taught early in residency training. Additionally, smoke safety can be implemented into certification examinations. Access to masks and smoke evacuation devices are an important part of dermatology training. Accreditation Council for Graduate Medical Education funds should be appropriated to provide for such resources.

Finally, and perhaps most importantly, continued awareness should be established in the dermatology community via standardized guidelines and periodic updates in the dermatology literature and lectures at local and national conferences. Not until these strategies are implemented will surgical smoke protection be viewed as a necessary and important component of routine practice when performing dermatologic surgical procedures.

To the Editor:

We read with great interest the recent Cutis article by Golda et al,¹ “Intraoperative Electrosurgical Smoke During Outpatient Surgery: A Survey of Dermatologic Surgeon and Staff Preferences.” We applaud the growing interest in the topic of dermatologist safety, as there are currently no established guidelines for precautions while performing surgical procedures. In 2018 we conducted a comprehensive review² to characterize the specific risks, hazard reduction strategies available, and current use of surgical smoke safety techniques during surgery among dermatologists, and ultimately recommend guidance based on the current available evidence. To conduct this review, we collected data from 45 manuscripts in the dermatology, surgery, infectious disease, obstetrics, and cancer biology literature. Herein, we summarize key findings.²

Dermatologic surgeons, residents, staff, and patients are exposed to many infectious, inhalational, chemical, and mutagenic hazards when performing procedures that liberate smoke and plume. These risks are commonplace; however, they are particularly notable during ablative laser and laser hair removal procedures, which produce a heavy plume (averaging >100,000 particles/cm³). Brief periods of heavy plume exposure also are commonplace during electrosurgery.

Infectious particles in surgical plume have been extensively studied, and viral transmission has been demonstrated in animal studies. Human papillomavirus transmission appears to be the most prevalent risk. Surgical smoke has been shown to cause acute and chronic inhalational injury in rat and sheep studies.^3-6

Additionally, chemicals with carcinogenic potential are present in surgical smoke and have been described.^7,8 Chemicals in the greatest quantity include hydrocarbons, nitriles, fatty acids, and phenols. Although there have been no human studies on smoke carcinogenesis to date, surgical smoke has been shown to have carcinogenic properties in vitro.

Given these risks—both evidence based and theoretical—we believe that diligent hazard reduction strategies should be employed whenever possible. Surgical masks and high-efficiency particulate air respirators, such as N95 respirator masks, have been well studied and do provide smoke protection. High-efficiency particulate air masks can be worn when possible, especially during procedures that produce heavy plume, though surgical masks are capable of filtering most of the noxious chemicals in surgical smoke. It should be noted that proper fit with minimal air leak is the most important aspect of overall performance.

Smoke evacuators provide another level of protection. The physician should consider the evacuator’s filtration efficiency, capture velocity, and suction strength when evaluating overall performance. Furthermore, the smoke collection tip should be within 2 in of the surgical field to maximize efficacy. Maintenance for smoke evacuation systems should include regular (as defined by manufacturer instructions) flushing of the smoke evacuator lines.

Despite the risks of surgical smoke and the available options of minimizing these risks, the hazards of surgical smoke and the importance of protection are likely underemphasized. Many dermatologic surgeons do not use surgical masks or smoke evacuators in routine practice, according to several survey studies.^9-11

It is important for the dermatologic community to consider effective ways of spreading awareness. We propose that surgical smoke safety be taught early in residency training. Additionally, smoke safety can be implemented into certification examinations. Access to masks and smoke evacuation devices are an important part of dermatology training. Accreditation Council for Graduate Medical Education funds should be appropriated to provide for such resources.

Finally, and perhaps most importantly, continued awareness should be established in the dermatology community via standardized guidelines and periodic updates in the dermatology literature and lectures at local and national conferences. Not until these strategies are implemented will surgical smoke protection be viewed as a necessary and important component of routine practice when performing dermatologic surgical procedures.

The Diagnosis: Nipple Adenoma (Florid Papillomatosis of the Nipple) 

Biopsy of the nodule showed florid papillary hyperplasia of the ductal epithelium within the dermis that was sharply demarcated from the background stroma (Figure, A and B). Neither cytological nor architectural atypia were evident. There was no notable necrosis (Figure C). There was a background of fibrosis whereby the glandular ductal structures assumed a somewhat irregular growth pattern within the dermis with attendant hemorrhage. The patient underwent complete excision of the lesion. No evidence of carcinoma was seen on the final pathology, and the final margins were negative. 

First described in 1923 and fully characterized in 1955, nipple adenoma (also known as florid papillomatosis of the nipple) is a benign proliferative neoplasm that originates in the lactiferous ducts of the nipple.^1,2 It most commonly affects women aged 40 to 50 years (range, 0-89 years); less than 5% of cases are reported in men.^3,4 It predominantly is unilateral, with only rare cases of bilateral papillomatosis reported. Patients often present with serous or serosanguineous discharge and an itching or burning sensation. Symptoms may worsen with the menstrual cycle.⁴ On physical examination, it presents as an ill-defined red nodule on the nipple with crusting, erosion, or erythema of the nipple surface. Although imaging generally is not used to confirm the diagnosis, mammography should be performed prior to biopsy to rule out underlying breast pathology. Dermoscopy may show linear cherry red structures or red serpiginous and annular structures.^5,6 The differential diagnosis of nipple adenoma includes Paget disease of the breast, adenomyoepithelioma, subareolar subsclerosing duct hyperplasia, syringomatous adenoma, adenosis tumor, low-grade adenosquamous carcinoma, low-grade ductal carcinoma in situ, tubular carcinoma, and sweat gland tumors.³  

Microscopic features of nipple adenoma have been categorized into 4 subtypes: sclerosing papillomatosis, papillomatosis, adenosis, and a mixed pattern.^3,7 The tumors may have keratin cysts and focal necrosis but no atypia, and the myoepithelial cell layer is retained. Nipple adenomas show a glandular proliferation in the dermis that is relatively well circumscribed with glands that vary in appearance between a simple adenosislike pattern of growth to a papillary hyperplasia and/or usual ductal hyperplasia growth pattern. A pseudoinfiltrative pattern can occur when the glandular epithelium is entrapped within stromal fibrosis; however, the myoepithelial layer is retained. Occasionally, the glandular epithelium can grow in continuity with the surface squamous epithelium of the nipple, clinically simulating Paget disease of the breast.⁸ Immunohistochemical stains, specifically p63, p40, calponin 1, h-caldesmon, cytokeratin 5/6, CD10, and α; smooth muscle actin, highlight the myoepithelial cells, while cytokeratin 7 identifies the ductal epithelium, supporting the diagnosis.⁶ In addition to biopsy and microscopic tissue examination, touch preparation cytology, curettage cytology, and fine needle aspiration techniques have been used to perform cytologic examination of the lesions, aiding in identification of the benign or malignant nature of the neoplasm.⁶ Nipple adenoma also is referred to as florid papillomatosis of the nipple, papillary adenoma, erosive adenomatosis, and subareolar duct papillomatosis.⁷ 

Although nipple adenoma is a benign tumor, up to 16.5% of affected patients had an ipsilateral or contralateral mammary carcinoma.⁹ The majority arose coincidentally but separately in the same breast, and carcinoma arose directly from the nipple adenoma in 8 cases; 3 cases were carcinomas that arose in men.¹⁰ A definitive association or causal relationship between nipple adenoma and subsequent development of breast cancer has not been identified, and the incidence of nipple adenoma in patients with a positive family history of breast cancer has not been examined. Therefore, although various treatments including cryosurgery, nipple splitting enucleation, and Mohs micrographic surgery have been proposed, complete excision remains the gold standard of therapy. Regular breast examinations and digital mammography are necessary to screen for local recurrences.  

The Diagnosis: Nipple Adenoma (Florid Papillomatosis of the Nipple) 

Biopsy of the nodule showed florid papillary hyperplasia of the ductal epithelium within the dermis that was sharply demarcated from the background stroma (Figure, A and B). Neither cytological nor architectural atypia were evident. There was no notable necrosis (Figure C). There was a background of fibrosis whereby the glandular ductal structures assumed a somewhat irregular growth pattern within the dermis with attendant hemorrhage. The patient underwent complete excision of the lesion. No evidence of carcinoma was seen on the final pathology, and the final margins were negative. 

First described in 1923 and fully characterized in 1955, nipple adenoma (also known as florid papillomatosis of the nipple) is a benign proliferative neoplasm that originates in the lactiferous ducts of the nipple.^1,2 It most commonly affects women aged 40 to 50 years (range, 0-89 years); less than 5% of cases are reported in men.^3,4 It predominantly is unilateral, with only rare cases of bilateral papillomatosis reported. Patients often present with serous or serosanguineous discharge and an itching or burning sensation. Symptoms may worsen with the menstrual cycle.⁴ On physical examination, it presents as an ill-defined red nodule on the nipple with crusting, erosion, or erythema of the nipple surface. Although imaging generally is not used to confirm the diagnosis, mammography should be performed prior to biopsy to rule out underlying breast pathology. Dermoscopy may show linear cherry red structures or red serpiginous and annular structures.^5,6 The differential diagnosis of nipple adenoma includes Paget disease of the breast, adenomyoepithelioma, subareolar subsclerosing duct hyperplasia, syringomatous adenoma, adenosis tumor, low-grade adenosquamous carcinoma, low-grade ductal carcinoma in situ, tubular carcinoma, and sweat gland tumors.³  

Microscopic features of nipple adenoma have been categorized into 4 subtypes: sclerosing papillomatosis, papillomatosis, adenosis, and a mixed pattern.^3,7 The tumors may have keratin cysts and focal necrosis but no atypia, and the myoepithelial cell layer is retained. Nipple adenomas show a glandular proliferation in the dermis that is relatively well circumscribed with glands that vary in appearance between a simple adenosislike pattern of growth to a papillary hyperplasia and/or usual ductal hyperplasia growth pattern. A pseudoinfiltrative pattern can occur when the glandular epithelium is entrapped within stromal fibrosis; however, the myoepithelial layer is retained. Occasionally, the glandular epithelium can grow in continuity with the surface squamous epithelium of the nipple, clinically simulating Paget disease of the breast.⁸ Immunohistochemical stains, specifically p63, p40, calponin 1, h-caldesmon, cytokeratin 5/6, CD10, and α; smooth muscle actin, highlight the myoepithelial cells, while cytokeratin 7 identifies the ductal epithelium, supporting the diagnosis.⁶ In addition to biopsy and microscopic tissue examination, touch preparation cytology, curettage cytology, and fine needle aspiration techniques have been used to perform cytologic examination of the lesions, aiding in identification of the benign or malignant nature of the neoplasm.⁶ Nipple adenoma also is referred to as florid papillomatosis of the nipple, papillary adenoma, erosive adenomatosis, and subareolar duct papillomatosis.⁷ 

Although nipple adenoma is a benign tumor, up to 16.5% of affected patients had an ipsilateral or contralateral mammary carcinoma.⁹ The majority arose coincidentally but separately in the same breast, and carcinoma arose directly from the nipple adenoma in 8 cases; 3 cases were carcinomas that arose in men.¹⁰ A definitive association or causal relationship between nipple adenoma and subsequent development of breast cancer has not been identified, and the incidence of nipple adenoma in patients with a positive family history of breast cancer has not been examined. Therefore, although various treatments including cryosurgery, nipple splitting enucleation, and Mohs micrographic surgery have been proposed, complete excision remains the gold standard of therapy. Regular breast examinations and digital mammography are necessary to screen for local recurrences.  

The Diagnosis: Nipple Adenoma (Florid Papillomatosis of the Nipple) 

Biopsy of the nodule showed florid papillary hyperplasia of the ductal epithelium within the dermis that was sharply demarcated from the background stroma (Figure, A and B). Neither cytological nor architectural atypia were evident. There was no notable necrosis (Figure C). There was a background of fibrosis whereby the glandular ductal structures assumed a somewhat irregular growth pattern within the dermis with attendant hemorrhage. The patient underwent complete excision of the lesion. No evidence of carcinoma was seen on the final pathology, and the final margins were negative. 

First described in 1923 and fully characterized in 1955, nipple adenoma (also known as florid papillomatosis of the nipple) is a benign proliferative neoplasm that originates in the lactiferous ducts of the nipple.^1,2 It most commonly affects women aged 40 to 50 years (range, 0-89 years); less than 5% of cases are reported in men.^3,4 It predominantly is unilateral, with only rare cases of bilateral papillomatosis reported. Patients often present with serous or serosanguineous discharge and an itching or burning sensation. Symptoms may worsen with the menstrual cycle.⁴ On physical examination, it presents as an ill-defined red nodule on the nipple with crusting, erosion, or erythema of the nipple surface. Although imaging generally is not used to confirm the diagnosis, mammography should be performed prior to biopsy to rule out underlying breast pathology. Dermoscopy may show linear cherry red structures or red serpiginous and annular structures.^5,6 The differential diagnosis of nipple adenoma includes Paget disease of the breast, adenomyoepithelioma, subareolar subsclerosing duct hyperplasia, syringomatous adenoma, adenosis tumor, low-grade adenosquamous carcinoma, low-grade ductal carcinoma in situ, tubular carcinoma, and sweat gland tumors.³  

Microscopic features of nipple adenoma have been categorized into 4 subtypes: sclerosing papillomatosis, papillomatosis, adenosis, and a mixed pattern.^3,7 The tumors may have keratin cysts and focal necrosis but no atypia, and the myoepithelial cell layer is retained. Nipple adenomas show a glandular proliferation in the dermis that is relatively well circumscribed with glands that vary in appearance between a simple adenosislike pattern of growth to a papillary hyperplasia and/or usual ductal hyperplasia growth pattern. A pseudoinfiltrative pattern can occur when the glandular epithelium is entrapped within stromal fibrosis; however, the myoepithelial layer is retained. Occasionally, the glandular epithelium can grow in continuity with the surface squamous epithelium of the nipple, clinically simulating Paget disease of the breast.⁸ Immunohistochemical stains, specifically p63, p40, calponin 1, h-caldesmon, cytokeratin 5/6, CD10, and α; smooth muscle actin, highlight the myoepithelial cells, while cytokeratin 7 identifies the ductal epithelium, supporting the diagnosis.⁶ In addition to biopsy and microscopic tissue examination, touch preparation cytology, curettage cytology, and fine needle aspiration techniques have been used to perform cytologic examination of the lesions, aiding in identification of the benign or malignant nature of the neoplasm.⁶ Nipple adenoma also is referred to as florid papillomatosis of the nipple, papillary adenoma, erosive adenomatosis, and subareolar duct papillomatosis.⁷ 

Although nipple adenoma is a benign tumor, up to 16.5% of affected patients had an ipsilateral or contralateral mammary carcinoma.⁹ The majority arose coincidentally but separately in the same breast, and carcinoma arose directly from the nipple adenoma in 8 cases; 3 cases were carcinomas that arose in men.¹⁰ A definitive association or causal relationship between nipple adenoma and subsequent development of breast cancer has not been identified, and the incidence of nipple adenoma in patients with a positive family history of breast cancer has not been examined. Therefore, although various treatments including cryosurgery, nipple splitting enucleation, and Mohs micrographic surgery have been proposed, complete excision remains the gold standard of therapy. Regular breast examinations and digital mammography are necessary to screen for local recurrences.  

Practice Gap

Habit-tic nail deformity results from repetitive manipulation of the cuticle and/or proximal nail fold. It most commonly affects one or both thumbnails and presents with a characteristic longitudinal midline furrow with parallel transverse ridges in the nail plate. Complications may include permanent onychodystrophy, frictional melanonychia, and infections. Treatment is challenging, as diagnosis first requires patient insight to the cause of symptoms. Therapeutic options include nonpharmacologic techniques (eg, occlusion of the nails to prevent trauma, cyanoacrylate adhesives, cognitive behavioral therapy) and pharmacologic techniques (eg, N-acetyl cysteine, selective serotonin reuptake inhibitors, tricyclic antidepressants, antipsychotics), with limited supporting data and potential adverse effects.¹

The Technique

Benzethonium chloride solution 0.2% is an antiseptic that creates a polymeric layer that binds to the skin. It normally is used to treat small skin erosions and prevent blisters. In patients with habit-tic nail deformity, we recommend once-daily application of benzethonium chloride to the proximal nail fold, thereby artificially recreating the cuticle and forming a sustainable barrier from trauma (Figure, A). Patients should be reminded not to manipulate the cuticle and/or nail fold during treatment. In one 36-year-old man with habit tic nail deformity, we saw clear nail growth after 4 months of treatment (Figure, B).

Practice Implications

Successful treatment of habit-tic nail deformity requires patients to have some insight into their behavior. The benzethonium chloride serves as a reminder for patients to stop picking as an unfamiliar artificial barrier and reminds them to substitute the picking behavior for another more positive behavior. Therefore, benzethonium chloride may be offered to patients as a novel therapy to both protect the cuticle and alter behavior in patients with habit-tic nail deformity, as it can be difficult to treat with few available therapies.

Allergic contact dermatitis to benzethonium chloride is a potential side effect and patients should be cautioned prior to treatment; however, it is extremely rare with 6 cases reported to date based on a PubMed search of articles indexed for MEDLINE using the terms allergic contact dermatitis and benzethonium chloride,² and much rarer than contact allergy to cyanoacrylates.

Practice Gap

Habit-tic nail deformity results from repetitive manipulation of the cuticle and/or proximal nail fold. It most commonly affects one or both thumbnails and presents with a characteristic longitudinal midline furrow with parallel transverse ridges in the nail plate. Complications may include permanent onychodystrophy, frictional melanonychia, and infections. Treatment is challenging, as diagnosis first requires patient insight to the cause of symptoms. Therapeutic options include nonpharmacologic techniques (eg, occlusion of the nails to prevent trauma, cyanoacrylate adhesives, cognitive behavioral therapy) and pharmacologic techniques (eg, N-acetyl cysteine, selective serotonin reuptake inhibitors, tricyclic antidepressants, antipsychotics), with limited supporting data and potential adverse effects.¹

The Technique

Benzethonium chloride solution 0.2% is an antiseptic that creates a polymeric layer that binds to the skin. It normally is used to treat small skin erosions and prevent blisters. In patients with habit-tic nail deformity, we recommend once-daily application of benzethonium chloride to the proximal nail fold, thereby artificially recreating the cuticle and forming a sustainable barrier from trauma (Figure, A). Patients should be reminded not to manipulate the cuticle and/or nail fold during treatment. In one 36-year-old man with habit tic nail deformity, we saw clear nail growth after 4 months of treatment (Figure, B).

Practice Implications

Successful treatment of habit-tic nail deformity requires patients to have some insight into their behavior. The benzethonium chloride serves as a reminder for patients to stop picking as an unfamiliar artificial barrier and reminds them to substitute the picking behavior for another more positive behavior. Therefore, benzethonium chloride may be offered to patients as a novel therapy to both protect the cuticle and alter behavior in patients with habit-tic nail deformity, as it can be difficult to treat with few available therapies.

Allergic contact dermatitis to benzethonium chloride is a potential side effect and patients should be cautioned prior to treatment; however, it is extremely rare with 6 cases reported to date based on a PubMed search of articles indexed for MEDLINE using the terms allergic contact dermatitis and benzethonium chloride,² and much rarer than contact allergy to cyanoacrylates.

Practice Gap

Habit-tic nail deformity results from repetitive manipulation of the cuticle and/or proximal nail fold. It most commonly affects one or both thumbnails and presents with a characteristic longitudinal midline furrow with parallel transverse ridges in the nail plate. Complications may include permanent onychodystrophy, frictional melanonychia, and infections. Treatment is challenging, as diagnosis first requires patient insight to the cause of symptoms. Therapeutic options include nonpharmacologic techniques (eg, occlusion of the nails to prevent trauma, cyanoacrylate adhesives, cognitive behavioral therapy) and pharmacologic techniques (eg, N-acetyl cysteine, selective serotonin reuptake inhibitors, tricyclic antidepressants, antipsychotics), with limited supporting data and potential adverse effects.¹

The Technique

Benzethonium chloride solution 0.2% is an antiseptic that creates a polymeric layer that binds to the skin. It normally is used to treat small skin erosions and prevent blisters. In patients with habit-tic nail deformity, we recommend once-daily application of benzethonium chloride to the proximal nail fold, thereby artificially recreating the cuticle and forming a sustainable barrier from trauma (Figure, A). Patients should be reminded not to manipulate the cuticle and/or nail fold during treatment. In one 36-year-old man with habit tic nail deformity, we saw clear nail growth after 4 months of treatment (Figure, B).

Practice Implications

Successful treatment of habit-tic nail deformity requires patients to have some insight into their behavior. The benzethonium chloride serves as a reminder for patients to stop picking as an unfamiliar artificial barrier and reminds them to substitute the picking behavior for another more positive behavior. Therefore, benzethonium chloride may be offered to patients as a novel therapy to both protect the cuticle and alter behavior in patients with habit-tic nail deformity, as it can be difficult to treat with few available therapies.

Allergic contact dermatitis to benzethonium chloride is a potential side effect and patients should be cautioned prior to treatment; however, it is extremely rare with 6 cases reported to date based on a PubMed search of articles indexed for MEDLINE using the terms allergic contact dermatitis and benzethonium chloride,² and much rarer than contact allergy to cyanoacrylates.

Case Report

A 53-year-old woman presented for an initial visit to the dermatology clinic for a growth under the right fifth fingernail of 1 year’s duration. She had no history of trauma to the digit or pain or bleeding. She self-treated with over-the-counter wart remover for several months without improvement. She reported no other skin concerns. She had a medical history of rheumatoid arthritis (RA) and basal cell carcinoma of the nose; she was taking methotrexate and adalimumab for the RA. She had a family history of melanoma in her father.

On physical examination, a firm nontender nodule was noted on the distal nail bed of the right fifth fingernail with onycholysis; the nail plate was otherwise intact (Figure 1). All other nails were normal. A plain radiograph of the involved digit showed no bony abnormality. Excisional biopsy of the nodule was performed and analyzed by histopathology (Figure 2). The biopsy specimen showed a benign epidermis that was acanthotic and surmounted by hyperkeratotic scale. The dermis was fibrotic with collagen bundles assuming a vertical orientation to the long axis of the epidermis, typical of a fibrokeratoma. There were no atypical features in the dermal component or epidermis (Figure 2). These findings were consistent with the diagnosis of acquired digital fibrokeratoma (ADF). The patient tolerated excisional biopsy well and had no evidence of recurrence 4 months following excision.

Comment

History and Clinical Presentation
First described by Bart et al¹ in 1968, ADF is a rare benign fibrous tumor localized to the nail bed or periungual area.¹ Typically, it presents as a solitary flesh-colored papule measuring 3 to 5 mm in diameter. It can be keratotic with a surrounding collarette of elevated skin. Acquired digital fibrokeratoma usually is localized to the digits of the hands or feet; when presenting subungually, it is more commonly found arising from the proximal matrix or nail bed of the great toe. Observed nail changes include longitudinal grooves, trachyonychia, subungual hyperkeratosis, and onycholysis.² The affected nail can be painful, depending on the size and location of the tumor.

Acquired digital fibrokeratoma is more commonly found in middle-aged men; however, it has been reported among patients of various ages and in both sexes.^1,3 In a study of 20 cases, the average duration before presenting for medical advice was 28 months.² Acquired digital fibrokeratoma arises sporadically; some patients report prior local trauma. Lesions typically do not self-resolve.

Diagnosis
The diagnosis of ADF is made using a combination of clinical and histopathological findings. Dermoscopy is helpful and may show homogenous white or milky white structures, likely representing hyperkeratosis, proliferation of capillaries, and an increase in collagen bundles with a surrounding collarette of scale.^4,5 Histopathology shows acanthosis and hyperkeratosis of the epidermis. Collagen bundles assume a characteristic vertical orientation to the long axis of the epidermis.

Two other histomorphologic subtypes, less common than the type I variant, are the type II variant, in which the number of fibroblasts is increased and the number of elastic fibers is decreased, and the type III variant, in which the stroma are edematous and cell poor. There is an even greater reduction in elastic tissue content in the type III variant than in the type I variant. There is evidence that type II ADFs exhibit more hyperkeratosis clinically than the other 2 subtypes, but from a practical perspective, this subclassification is not conducted in routine practice because it does not have clinical significance.⁵

Differential Diagnosis
The clinical differential diagnosis of ADF is broad and includes squamous cell carcinoma, onychomatricoma, onychopapilloma, verruca vulgaris, supernumerary digit, neurofibroma, cellular digital fibroma, and Koenen tumor (periungual fibroma). Almost all of these entities are easily differentiated from ADF on biopsy. A fibrokeratoma does not exhibit the atypia seen in squamous cell carcinoma. The multiple fibroepithelial projections and nail plate perforations characteristic of onychomatricoma are not observed in ADF. Onychopapilloma shows acanthosis and papillomatosis, similar to ADF; however, onychopapilloma lacks the characteristic vertical orientation of collagen in ADF. Verruca vulgaris classically shows koilocytosis, dilated blood vessels in papillae, and hypergranulosis. A supernumerary digit clinically lacks a collarette of scale and often presents in a bilateral fashion on the lateral fifth digits in children; histopathologically, a supernumerary digit is distinct from an ADF in that nerve bundles are abundant in the dermis, defining a form of amputation neuroma. Neurofibroma exhibits a spindle cell proliferation that assumes a patternless disposition in the dermis, accompanied by mucin, mast cells, and delicate collagen. The defining cell populace has a typical serpiginous nuclear outline that is characteristic of a Schwann cell. Cellular digital fibroma can present similar to ADF; it is considered by some to be a mucin-poor variant of superficial acral fibromyxoma. Its morphology is distinct: a proliferation of bland-appearing spindled cells exhibiting a storiform or fascicular growth pattern and CD34 positivity.

The differential diagnosis to consider when ADF is suspected is a Koenen tumor, which resembles a fibrokeratoma clinically and also is localized to the digits. Koenen tumors can be differentiated from fibrokeratoma by its association with tuberous sclerosis; a multiple, rather than solitary, presentation; a distinctive clove-shaped gross appearance; and an appearance on histopathology of stellate-shaped fibroblasts with occasional giant cells. Despite these important differences, Koenen tumor does exhibit a striking morphologic similarity to ADF, given that the vertical orientation of collagen bundles in Koenen tumor is virtually identical to ADF.⁶

Management
There are no known associations between ADF and medication use, including methotrexate and adalimumab, which our patient was taking; additionally, no association with RA or other systemic disorder has been reported.² The preferred treatment of ADF is complete excision to the basal attachment of the tumor; recurrence is uncommon. Alternative therapies include destructive methods, such as cryotherapy, CO₂ laser ablation, and electrodesiccation.²

Case Report

A 53-year-old woman presented for an initial visit to the dermatology clinic for a growth under the right fifth fingernail of 1 year’s duration. She had no history of trauma to the digit or pain or bleeding. She self-treated with over-the-counter wart remover for several months without improvement. She reported no other skin concerns. She had a medical history of rheumatoid arthritis (RA) and basal cell carcinoma of the nose; she was taking methotrexate and adalimumab for the RA. She had a family history of melanoma in her father.

On physical examination, a firm nontender nodule was noted on the distal nail bed of the right fifth fingernail with onycholysis; the nail plate was otherwise intact (Figure 1). All other nails were normal. A plain radiograph of the involved digit showed no bony abnormality. Excisional biopsy of the nodule was performed and analyzed by histopathology (Figure 2). The biopsy specimen showed a benign epidermis that was acanthotic and surmounted by hyperkeratotic scale. The dermis was fibrotic with collagen bundles assuming a vertical orientation to the long axis of the epidermis, typical of a fibrokeratoma. There were no atypical features in the dermal component or epidermis (Figure 2). These findings were consistent with the diagnosis of acquired digital fibrokeratoma (ADF). The patient tolerated excisional biopsy well and had no evidence of recurrence 4 months following excision.

Comment

History and Clinical Presentation
First described by Bart et al¹ in 1968, ADF is a rare benign fibrous tumor localized to the nail bed or periungual area.¹ Typically, it presents as a solitary flesh-colored papule measuring 3 to 5 mm in diameter. It can be keratotic with a surrounding collarette of elevated skin. Acquired digital fibrokeratoma usually is localized to the digits of the hands or feet; when presenting subungually, it is more commonly found arising from the proximal matrix or nail bed of the great toe. Observed nail changes include longitudinal grooves, trachyonychia, subungual hyperkeratosis, and onycholysis.² The affected nail can be painful, depending on the size and location of the tumor.

Acquired digital fibrokeratoma is more commonly found in middle-aged men; however, it has been reported among patients of various ages and in both sexes.^1,3 In a study of 20 cases, the average duration before presenting for medical advice was 28 months.² Acquired digital fibrokeratoma arises sporadically; some patients report prior local trauma. Lesions typically do not self-resolve.

Diagnosis
The diagnosis of ADF is made using a combination of clinical and histopathological findings. Dermoscopy is helpful and may show homogenous white or milky white structures, likely representing hyperkeratosis, proliferation of capillaries, and an increase in collagen bundles with a surrounding collarette of scale.^4,5 Histopathology shows acanthosis and hyperkeratosis of the epidermis. Collagen bundles assume a characteristic vertical orientation to the long axis of the epidermis.

Two other histomorphologic subtypes, less common than the type I variant, are the type II variant, in which the number of fibroblasts is increased and the number of elastic fibers is decreased, and the type III variant, in which the stroma are edematous and cell poor. There is an even greater reduction in elastic tissue content in the type III variant than in the type I variant. There is evidence that type II ADFs exhibit more hyperkeratosis clinically than the other 2 subtypes, but from a practical perspective, this subclassification is not conducted in routine practice because it does not have clinical significance.⁵

Differential Diagnosis
The clinical differential diagnosis of ADF is broad and includes squamous cell carcinoma, onychomatricoma, onychopapilloma, verruca vulgaris, supernumerary digit, neurofibroma, cellular digital fibroma, and Koenen tumor (periungual fibroma). Almost all of these entities are easily differentiated from ADF on biopsy. A fibrokeratoma does not exhibit the atypia seen in squamous cell carcinoma. The multiple fibroepithelial projections and nail plate perforations characteristic of onychomatricoma are not observed in ADF. Onychopapilloma shows acanthosis and papillomatosis, similar to ADF; however, onychopapilloma lacks the characteristic vertical orientation of collagen in ADF. Verruca vulgaris classically shows koilocytosis, dilated blood vessels in papillae, and hypergranulosis. A supernumerary digit clinically lacks a collarette of scale and often presents in a bilateral fashion on the lateral fifth digits in children; histopathologically, a supernumerary digit is distinct from an ADF in that nerve bundles are abundant in the dermis, defining a form of amputation neuroma. Neurofibroma exhibits a spindle cell proliferation that assumes a patternless disposition in the dermis, accompanied by mucin, mast cells, and delicate collagen. The defining cell populace has a typical serpiginous nuclear outline that is characteristic of a Schwann cell. Cellular digital fibroma can present similar to ADF; it is considered by some to be a mucin-poor variant of superficial acral fibromyxoma. Its morphology is distinct: a proliferation of bland-appearing spindled cells exhibiting a storiform or fascicular growth pattern and CD34 positivity.

The differential diagnosis to consider when ADF is suspected is a Koenen tumor, which resembles a fibrokeratoma clinically and also is localized to the digits. Koenen tumors can be differentiated from fibrokeratoma by its association with tuberous sclerosis; a multiple, rather than solitary, presentation; a distinctive clove-shaped gross appearance; and an appearance on histopathology of stellate-shaped fibroblasts with occasional giant cells. Despite these important differences, Koenen tumor does exhibit a striking morphologic similarity to ADF, given that the vertical orientation of collagen bundles in Koenen tumor is virtually identical to ADF.⁶

Management
There are no known associations between ADF and medication use, including methotrexate and adalimumab, which our patient was taking; additionally, no association with RA or other systemic disorder has been reported.² The preferred treatment of ADF is complete excision to the basal attachment of the tumor; recurrence is uncommon. Alternative therapies include destructive methods, such as cryotherapy, CO₂ laser ablation, and electrodesiccation.²

Case Report

A 53-year-old woman presented for an initial visit to the dermatology clinic for a growth under the right fifth fingernail of 1 year’s duration. She had no history of trauma to the digit or pain or bleeding. She self-treated with over-the-counter wart remover for several months without improvement. She reported no other skin concerns. She had a medical history of rheumatoid arthritis (RA) and basal cell carcinoma of the nose; she was taking methotrexate and adalimumab for the RA. She had a family history of melanoma in her father.

On physical examination, a firm nontender nodule was noted on the distal nail bed of the right fifth fingernail with onycholysis; the nail plate was otherwise intact (Figure 1). All other nails were normal. A plain radiograph of the involved digit showed no bony abnormality. Excisional biopsy of the nodule was performed and analyzed by histopathology (Figure 2). The biopsy specimen showed a benign epidermis that was acanthotic and surmounted by hyperkeratotic scale. The dermis was fibrotic with collagen bundles assuming a vertical orientation to the long axis of the epidermis, typical of a fibrokeratoma. There were no atypical features in the dermal component or epidermis (Figure 2). These findings were consistent with the diagnosis of acquired digital fibrokeratoma (ADF). The patient tolerated excisional biopsy well and had no evidence of recurrence 4 months following excision.

Comment

History and Clinical Presentation
First described by Bart et al¹ in 1968, ADF is a rare benign fibrous tumor localized to the nail bed or periungual area.¹ Typically, it presents as a solitary flesh-colored papule measuring 3 to 5 mm in diameter. It can be keratotic with a surrounding collarette of elevated skin. Acquired digital fibrokeratoma usually is localized to the digits of the hands or feet; when presenting subungually, it is more commonly found arising from the proximal matrix or nail bed of the great toe. Observed nail changes include longitudinal grooves, trachyonychia, subungual hyperkeratosis, and onycholysis.² The affected nail can be painful, depending on the size and location of the tumor.

Acquired digital fibrokeratoma is more commonly found in middle-aged men; however, it has been reported among patients of various ages and in both sexes.^1,3 In a study of 20 cases, the average duration before presenting for medical advice was 28 months.² Acquired digital fibrokeratoma arises sporadically; some patients report prior local trauma. Lesions typically do not self-resolve.

Diagnosis
The diagnosis of ADF is made using a combination of clinical and histopathological findings. Dermoscopy is helpful and may show homogenous white or milky white structures, likely representing hyperkeratosis, proliferation of capillaries, and an increase in collagen bundles with a surrounding collarette of scale.^4,5 Histopathology shows acanthosis and hyperkeratosis of the epidermis. Collagen bundles assume a characteristic vertical orientation to the long axis of the epidermis.

Two other histomorphologic subtypes, less common than the type I variant, are the type II variant, in which the number of fibroblasts is increased and the number of elastic fibers is decreased, and the type III variant, in which the stroma are edematous and cell poor. There is an even greater reduction in elastic tissue content in the type III variant than in the type I variant. There is evidence that type II ADFs exhibit more hyperkeratosis clinically than the other 2 subtypes, but from a practical perspective, this subclassification is not conducted in routine practice because it does not have clinical significance.⁵

Differential Diagnosis
The clinical differential diagnosis of ADF is broad and includes squamous cell carcinoma, onychomatricoma, onychopapilloma, verruca vulgaris, supernumerary digit, neurofibroma, cellular digital fibroma, and Koenen tumor (periungual fibroma). Almost all of these entities are easily differentiated from ADF on biopsy. A fibrokeratoma does not exhibit the atypia seen in squamous cell carcinoma. The multiple fibroepithelial projections and nail plate perforations characteristic of onychomatricoma are not observed in ADF. Onychopapilloma shows acanthosis and papillomatosis, similar to ADF; however, onychopapilloma lacks the characteristic vertical orientation of collagen in ADF. Verruca vulgaris classically shows koilocytosis, dilated blood vessels in papillae, and hypergranulosis. A supernumerary digit clinically lacks a collarette of scale and often presents in a bilateral fashion on the lateral fifth digits in children; histopathologically, a supernumerary digit is distinct from an ADF in that nerve bundles are abundant in the dermis, defining a form of amputation neuroma. Neurofibroma exhibits a spindle cell proliferation that assumes a patternless disposition in the dermis, accompanied by mucin, mast cells, and delicate collagen. The defining cell populace has a typical serpiginous nuclear outline that is characteristic of a Schwann cell. Cellular digital fibroma can present similar to ADF; it is considered by some to be a mucin-poor variant of superficial acral fibromyxoma. Its morphology is distinct: a proliferation of bland-appearing spindled cells exhibiting a storiform or fascicular growth pattern and CD34 positivity.

The differential diagnosis to consider when ADF is suspected is a Koenen tumor, which resembles a fibrokeratoma clinically and also is localized to the digits. Koenen tumors can be differentiated from fibrokeratoma by its association with tuberous sclerosis; a multiple, rather than solitary, presentation; a distinctive clove-shaped gross appearance; and an appearance on histopathology of stellate-shaped fibroblasts with occasional giant cells. Despite these important differences, Koenen tumor does exhibit a striking morphologic similarity to ADF, given that the vertical orientation of collagen bundles in Koenen tumor is virtually identical to ADF.⁶

Management
There are no known associations between ADF and medication use, including methotrexate and adalimumab, which our patient was taking; additionally, no association with RA or other systemic disorder has been reported.² The preferred treatment of ADF is complete excision to the basal attachment of the tumor; recurrence is uncommon. Alternative therapies include destructive methods, such as cryotherapy, CO₂ laser ablation, and electrodesiccation.²

Patients frequently present to dermatologists with nail disorders as their chief concern. Alternatively, nail conditions may be encountered by the examining physician as an incidental finding that may be a clue to underlying systemic disease. Competence in the diagnosis and treatment of nail diseases can drastically improve patient quality of life and can be lifesaving,¹ but many dermatologists find management of nail diseases challenging.² Bridging this educational gap begins with dermatology resident and medical student education. In a collaboration with dermatology educators, the American Academy of Dermatology (AAD) prepared a free online core curriculum for medical students that covers the essential concepts of dermatology. We sought to determine the integration of nail education in the AAD Basic Dermatology Curriculum.

Methods

A cross-sectional study of the AAD Basic Dermatology Curriculum was conducted to determine nail disease content. The curriculum modules were downloaded in June 2018,³ and mentions of nails were recorded and evaluated for overall quantities and relevant content. References to nail procedures and diagnostic techniques including nail biopsies, fungal cultures, microscopy on nail scrapings, nail clippings, and nail-related cancers also were assessed in the analysis.

Results

Of 342 patients discussed in cases and quizzes, nails were mentioned for 19 patients (89 times total)(Table 1). Additionally, there were 2 mentions each of nail clippings and nail tumors, 0 mentions of nail biopsies, and 1 mention each of fungal cultures and microscopy on nail scrapings (Table 1). Of the 40 modules, nails were mentioned in 12 modules (Table 2) and 6 introductions to the modules (Table 1). There were no mentions of the terms nails, subungual, or onychomycosis in the learning objectives.³

Comment

Our study demonstrates a paucity of content relevant to nails in the AAD Basic Dermatology Curriculum. Medical students are missing an important opportunity to learn about diagnosis and management of nail conditions and may incorrectly conclude that nail expertise is not essential to becoming a competent board-certified dermatologist.

Particularly concerning is the exclusion of nail examinations in the skin exam module addressing full-body skin examinations (0 mentions in 31 slides). This curriculum may negatively influence medical students and may then follow at the resident level, with a study reporting that 50.3% (69/137) of residents examine nails only when the patient brings it to their attention.⁴

Most concerning was the inadequate coverage of nail unit melanoma in the melanoma module (1 mention in 53 slides). Furthermore, the ABCDE—asymmetry, border, color, diameter, and evolving—mnemonic for cutaneous melanoma was covered in 6 slides in this module, and the ABCDEF—family history added—mnemonic for nail unit melanoma was completely excluded. Not surprisingly, resident knowledge of melanonychia diagnosis is deficient, with a prior study demonstrating that 62% (88/142) of residents were not confident diagnosing and managing patients with melanonychia, and only 88% (125/142) of residents were aware of the nail melanoma mnemonic.⁴

Similarly, nail biopsy for melanonychia diagnosis was excluded from the curriculum, whereas skin biopsy was thoroughly discussed in the context of a cutaneous melanoma diagnosis. This deficient teaching may track to the dermatology resident curriculum, as a survey of third-year dermatology residents (N=240) showed that 58% performed 10 or fewer nail procedures, and one-third of residents felt incompetent in nail surgery.⁵

We acknowledge that the AAD Basic Dermatology Curriculum is simply an introduction to dermatology. However, given that dermatologists are among the major specialists who care for nail patients, we advocate for more content on nail diseases in this curriculum. Nails can easily be incorporated into existing modules, and a new module specifically dedicated to nail disease should be added. Moreover, we envision that our findings will positively reflect on competence in treating nail disease for dermatology residents.

Patients frequently present to dermatologists with nail disorders as their chief concern. Alternatively, nail conditions may be encountered by the examining physician as an incidental finding that may be a clue to underlying systemic disease. Competence in the diagnosis and treatment of nail diseases can drastically improve patient quality of life and can be lifesaving,¹ but many dermatologists find management of nail diseases challenging.² Bridging this educational gap begins with dermatology resident and medical student education. In a collaboration with dermatology educators, the American Academy of Dermatology (AAD) prepared a free online core curriculum for medical students that covers the essential concepts of dermatology. We sought to determine the integration of nail education in the AAD Basic Dermatology Curriculum.

Methods

A cross-sectional study of the AAD Basic Dermatology Curriculum was conducted to determine nail disease content. The curriculum modules were downloaded in June 2018,³ and mentions of nails were recorded and evaluated for overall quantities and relevant content. References to nail procedures and diagnostic techniques including nail biopsies, fungal cultures, microscopy on nail scrapings, nail clippings, and nail-related cancers also were assessed in the analysis.

Results

Of 342 patients discussed in cases and quizzes, nails were mentioned for 19 patients (89 times total)(Table 1). Additionally, there were 2 mentions each of nail clippings and nail tumors, 0 mentions of nail biopsies, and 1 mention each of fungal cultures and microscopy on nail scrapings (Table 1). Of the 40 modules, nails were mentioned in 12 modules (Table 2) and 6 introductions to the modules (Table 1). There were no mentions of the terms nails, subungual, or onychomycosis in the learning objectives.³

Comment

Our study demonstrates a paucity of content relevant to nails in the AAD Basic Dermatology Curriculum. Medical students are missing an important opportunity to learn about diagnosis and management of nail conditions and may incorrectly conclude that nail expertise is not essential to becoming a competent board-certified dermatologist.

Particularly concerning is the exclusion of nail examinations in the skin exam module addressing full-body skin examinations (0 mentions in 31 slides). This curriculum may negatively influence medical students and may then follow at the resident level, with a study reporting that 50.3% (69/137) of residents examine nails only when the patient brings it to their attention.⁴

Most concerning was the inadequate coverage of nail unit melanoma in the melanoma module (1 mention in 53 slides). Furthermore, the ABCDE—asymmetry, border, color, diameter, and evolving—mnemonic for cutaneous melanoma was covered in 6 slides in this module, and the ABCDEF—family history added—mnemonic for nail unit melanoma was completely excluded. Not surprisingly, resident knowledge of melanonychia diagnosis is deficient, with a prior study demonstrating that 62% (88/142) of residents were not confident diagnosing and managing patients with melanonychia, and only 88% (125/142) of residents were aware of the nail melanoma mnemonic.⁴

Similarly, nail biopsy for melanonychia diagnosis was excluded from the curriculum, whereas skin biopsy was thoroughly discussed in the context of a cutaneous melanoma diagnosis. This deficient teaching may track to the dermatology resident curriculum, as a survey of third-year dermatology residents (N=240) showed that 58% performed 10 or fewer nail procedures, and one-third of residents felt incompetent in nail surgery.⁵

We acknowledge that the AAD Basic Dermatology Curriculum is simply an introduction to dermatology. However, given that dermatologists are among the major specialists who care for nail patients, we advocate for more content on nail diseases in this curriculum. Nails can easily be incorporated into existing modules, and a new module specifically dedicated to nail disease should be added. Moreover, we envision that our findings will positively reflect on competence in treating nail disease for dermatology residents.

Patients frequently present to dermatologists with nail disorders as their chief concern. Alternatively, nail conditions may be encountered by the examining physician as an incidental finding that may be a clue to underlying systemic disease. Competence in the diagnosis and treatment of nail diseases can drastically improve patient quality of life and can be lifesaving,¹ but many dermatologists find management of nail diseases challenging.² Bridging this educational gap begins with dermatology resident and medical student education. In a collaboration with dermatology educators, the American Academy of Dermatology (AAD) prepared a free online core curriculum for medical students that covers the essential concepts of dermatology. We sought to determine the integration of nail education in the AAD Basic Dermatology Curriculum.

Methods

A cross-sectional study of the AAD Basic Dermatology Curriculum was conducted to determine nail disease content. The curriculum modules were downloaded in June 2018,³ and mentions of nails were recorded and evaluated for overall quantities and relevant content. References to nail procedures and diagnostic techniques including nail biopsies, fungal cultures, microscopy on nail scrapings, nail clippings, and nail-related cancers also were assessed in the analysis.

Results

Of 342 patients discussed in cases and quizzes, nails were mentioned for 19 patients (89 times total)(Table 1). Additionally, there were 2 mentions each of nail clippings and nail tumors, 0 mentions of nail biopsies, and 1 mention each of fungal cultures and microscopy on nail scrapings (Table 1). Of the 40 modules, nails were mentioned in 12 modules (Table 2) and 6 introductions to the modules (Table 1). There were no mentions of the terms nails, subungual, or onychomycosis in the learning objectives.³

Comment

Our study demonstrates a paucity of content relevant to nails in the AAD Basic Dermatology Curriculum. Medical students are missing an important opportunity to learn about diagnosis and management of nail conditions and may incorrectly conclude that nail expertise is not essential to becoming a competent board-certified dermatologist.

Particularly concerning is the exclusion of nail examinations in the skin exam module addressing full-body skin examinations (0 mentions in 31 slides). This curriculum may negatively influence medical students and may then follow at the resident level, with a study reporting that 50.3% (69/137) of residents examine nails only when the patient brings it to their attention.⁴

Most concerning was the inadequate coverage of nail unit melanoma in the melanoma module (1 mention in 53 slides). Furthermore, the ABCDE—asymmetry, border, color, diameter, and evolving—mnemonic for cutaneous melanoma was covered in 6 slides in this module, and the ABCDEF—family history added—mnemonic for nail unit melanoma was completely excluded. Not surprisingly, resident knowledge of melanonychia diagnosis is deficient, with a prior study demonstrating that 62% (88/142) of residents were not confident diagnosing and managing patients with melanonychia, and only 88% (125/142) of residents were aware of the nail melanoma mnemonic.⁴

Similarly, nail biopsy for melanonychia diagnosis was excluded from the curriculum, whereas skin biopsy was thoroughly discussed in the context of a cutaneous melanoma diagnosis. This deficient teaching may track to the dermatology resident curriculum, as a survey of third-year dermatology residents (N=240) showed that 58% performed 10 or fewer nail procedures, and one-third of residents felt incompetent in nail surgery.⁵

We acknowledge that the AAD Basic Dermatology Curriculum is simply an introduction to dermatology. However, given that dermatologists are among the major specialists who care for nail patients, we advocate for more content on nail diseases in this curriculum. Nails can easily be incorporated into existing modules, and a new module specifically dedicated to nail disease should be added. Moreover, we envision that our findings will positively reflect on competence in treating nail disease for dermatology residents.

Practice Gap

Onychocryptosis, or ingrown toenail, is a highly prevalent nail condition characterized by penetration of the periungual skin by the nail plate (Figure, A). Patients may report pain either while at rest or walking, which may be debilitating in severe cases and may adversely affect daily living. Treatment may be approached using conservative or surgical therapies. Conservative methods are noninvasive and appropriate for mild cases but require excellent compliance. Although nail trimming is the simplest method, it may necessitate cutting soft tissue, particularly when the nail is anchored deep within the periungual skin. Another conservative method is taping, which aims to separate the nail fold from the offending nail edge by using an adhesive. In common practice, the adhesive often detaches within a few hours, which is further exacerbated by moisture from sweating or bathing.¹ Therefore, for effective treatment of onychocryptosis, the tape typically must be reapplied multiple times per day, limiting compliance.

Tools

We propose using kinesiology tape to treat onychocryptosis. Kinesiology tape is a highly elastic adhesive that was originally employed by athletes to relieve pain while supporting muscles, tendons, and ligaments during strenuous activity. We hypothesized that its stronger adherent properties and greater elasticity would be advantageous for treatment of onychocryptosis compared to standard tape.

The Technique

A strip of tape is cut to approximately 10 to 15 mm×5 cm and is applied once daily to the lateral nail fold, pulling it away from the nail plate in oblique and proximal directions and then wrapping it around the plantar surface dorsally (Figure, B). Kinesiology tape properties allow for less frequent application and greater tension to be applied to the nail fold while reducing the risk for vasoconstriction, as the tape does not need to be fully wrapped around the digit for reliable adherence.

Practice Implications

Kinesiology tape adheres more firmly than other tapes and requires less frequent applications. Use of kinesiology tape for onychocryptosis therapy often is effective and may negate the need for more invasive procedures and improve quality of life during and after treatment.

Practice Gap

Onychocryptosis, or ingrown toenail, is a highly prevalent nail condition characterized by penetration of the periungual skin by the nail plate (Figure, A). Patients may report pain either while at rest or walking, which may be debilitating in severe cases and may adversely affect daily living. Treatment may be approached using conservative or surgical therapies. Conservative methods are noninvasive and appropriate for mild cases but require excellent compliance. Although nail trimming is the simplest method, it may necessitate cutting soft tissue, particularly when the nail is anchored deep within the periungual skin. Another conservative method is taping, which aims to separate the nail fold from the offending nail edge by using an adhesive. In common practice, the adhesive often detaches within a few hours, which is further exacerbated by moisture from sweating or bathing.¹ Therefore, for effective treatment of onychocryptosis, the tape typically must be reapplied multiple times per day, limiting compliance.

Tools

We propose using kinesiology tape to treat onychocryptosis. Kinesiology tape is a highly elastic adhesive that was originally employed by athletes to relieve pain while supporting muscles, tendons, and ligaments during strenuous activity. We hypothesized that its stronger adherent properties and greater elasticity would be advantageous for treatment of onychocryptosis compared to standard tape.

The Technique

A strip of tape is cut to approximately 10 to 15 mm×5 cm and is applied once daily to the lateral nail fold, pulling it away from the nail plate in oblique and proximal directions and then wrapping it around the plantar surface dorsally (Figure, B). Kinesiology tape properties allow for less frequent application and greater tension to be applied to the nail fold while reducing the risk for vasoconstriction, as the tape does not need to be fully wrapped around the digit for reliable adherence.

Practice Implications

Kinesiology tape adheres more firmly than other tapes and requires less frequent applications. Use of kinesiology tape for onychocryptosis therapy often is effective and may negate the need for more invasive procedures and improve quality of life during and after treatment.

Practice Gap

Onychocryptosis, or ingrown toenail, is a highly prevalent nail condition characterized by penetration of the periungual skin by the nail plate (Figure, A). Patients may report pain either while at rest or walking, which may be debilitating in severe cases and may adversely affect daily living. Treatment may be approached using conservative or surgical therapies. Conservative methods are noninvasive and appropriate for mild cases but require excellent compliance. Although nail trimming is the simplest method, it may necessitate cutting soft tissue, particularly when the nail is anchored deep within the periungual skin. Another conservative method is taping, which aims to separate the nail fold from the offending nail edge by using an adhesive. In common practice, the adhesive often detaches within a few hours, which is further exacerbated by moisture from sweating or bathing.¹ Therefore, for effective treatment of onychocryptosis, the tape typically must be reapplied multiple times per day, limiting compliance.

Tools

We propose using kinesiology tape to treat onychocryptosis. Kinesiology tape is a highly elastic adhesive that was originally employed by athletes to relieve pain while supporting muscles, tendons, and ligaments during strenuous activity. We hypothesized that its stronger adherent properties and greater elasticity would be advantageous for treatment of onychocryptosis compared to standard tape.

The Technique

A strip of tape is cut to approximately 10 to 15 mm×5 cm and is applied once daily to the lateral nail fold, pulling it away from the nail plate in oblique and proximal directions and then wrapping it around the plantar surface dorsally (Figure, B). Kinesiology tape properties allow for less frequent application and greater tension to be applied to the nail fold while reducing the risk for vasoconstriction, as the tape does not need to be fully wrapped around the digit for reliable adherence.

Practice Implications

Kinesiology tape adheres more firmly than other tapes and requires less frequent applications. Use of kinesiology tape for onychocryptosis therapy often is effective and may negate the need for more invasive procedures and improve quality of life during and after treatment.

Onychomycosis is a fungal infection of the nail unit due to dermatophytes, yeasts, and nondermatophyte molds (NDMs). It accounts for approximately 50% of all nail disorders seen in clinical practice and is estimated to affect 10% to 12% of the US population.^1,2 Oral medications approved by the US Food and Drug Administration (FDA) include terbinafine and itraconazole, which have demonstrated good efficacy in treating onychomycosis but are associated with potential drug-drug interactions and systemic side effects.^3,4 Although liver failure associated with these drugs is rare,⁵ many patients are anxious about systemic adverse events and therefore prefer to use topical therapies for onychomycosis.

Many patients desire topical therapy but not every patient is an appropriate candidate. Patients who will likely respond well to topical therapy include those with superficial onychomycosis, distal lateral subungual onychomycosis that involves less than 50% of the nail plate surface area (without matrix involvement and a nail plate thickness less than 2 mm), and only up to 3 or 4 nails affected.⁶ In patients who have contraindications to oral therapy, topical therapy may be the only treatment option. To maximize efficacy of FDA-approved topical agents for onychomycosis therapy, patient education is of utmost importance. Failure to properly counsel the patient on proper medication application may result in decreased antifungal efficacy; poor patient compliance due to lack of improvement; and progression of disease, leading to increased onychodystrophy and pain.

Before initiating therapy, patients should be counseled that treatment with topical drugs is long, requiring daily application of the medication for 6 months for fingernails and 12 months for toenails, based on average nail growth rates (2–3 mm per month for fingernails; 1 mm per month for toenails).⁷ Patients also are advised to avoid nail polish application during the course of therapy, as clinical trials were performed without nail polish and the true efficacy with nail polish is unknown.^8-10 Because patients who have had onychomycosis for shorter durations generally have better cure rates than those who have disease for longer durations, it is prudent to initiate topical therapy as early as possible.^11,12 Treating the feet with an antifungal while treating the nails for onychomycosis further enhances efficacy.^13,14 There are 3 FDA-approved topical therapies for onychomycosis: ciclopirox nail lacquer 8%, efinaconazole solution 10%, and tavaborole solution 5%.^15-17

Ciclopirox is a hydroxypyridone with broad-spectrum antimicrobial activity against dermatophytes, NDMs, yeasts, and bacteria. Its mechanism of action is to chelate polyvalent cations, such as Fe³⁺, and inhibit fungal metal-dependent enzymes responsible for the degradation of toxic metabolites.¹⁵ Ciclopirox nail lacquer 8% was FDA approved for the treatment of onychomycosis in 1999, making it the first topical approved for this purpose. Its indication is for immunocompetent patients with mild to moderate onychomycosis (Trichophyton rubrum) without lunula involvement, with mycologic cure rates of 29% to 36% and complete cure rates of 5.5% to 8.5% (toenails).¹⁵ It is the only FDA-approved topical treatment for both fingernails and toenails. Using a brush applicator, it is applied daily to the nail plate and its undersurface, hyponychium, and 5 mm of the surrounding skin. It is important to counsel the patient to remove the lacquer from the nail plate weekly because failure to do so will result in accumulation of numerous layers of medication, such that the active drug cannot reach the site of infection (Figures 1 and 2). The nail plate also should be trimmed and filed weekly by the patient, with monthly clipping/debridement by a physician recommended.^6,15

Efinaconazole is a triazole with antifungal activity against dermatophytes, NDMs, and Candida species. Its mechanism of action is inhibition of lanosterol 14α-demethylase, an enzyme involved in the biosynthesis of ergosterol, which is a component of the fungal cell membrane. Efinaconazole solution 10% was FDA approved in June 2014 for the treatment of toenail onychomycosis due to T rubrum and Trichophyton mentagrophytes, with package insert mycologic cure rates of 53.4% to 55.2% and complete cure rates of 15.2% to 17.8%.^9,16 It is applied with a brush applicator to the nail plate, as well as its undersurface, nail folds, and hyponychium. Two drops are recommended for the great toenail and one drop for all other toenails, and no removal of the solution or debridement is required.^6,16

Tavaborole is a benzoxaborole with antifungal activity against dermatophytes, NDMs, and yeasts. Its mechanism of action is inhibition of fungal aminoacyl transfer RNA synthetase, thus impeding protein synthesis.¹⁸ Tavaborole solution 5% was FDA approved in July 2014 for the treatment of toenail onychomycosis due to T rubrum and T mentagrophytes, with mycologic cure rates of 31.1% and 35.9% and complete cure rates of 6.5% and 9.1%, respectively.^11,17 It is applied with a glass pointed-tip dropper to the nail plate, such that the entire nail is covered as well as under the nail tip. No removal of the solution or debridement is required.¹⁷

Topical therapies for onychomycosis require long treatment durations, thus excellent compliance and adherence to the treatment protocol are vital to maximize efficacy. Dermatologists who prescribe ciclopirox nail lacquer 8% should counsel patients to remove the lacquer with alcohol weekly, such that the antifungal penetrates the nail plate to reach the site of infection. Monthly debridement also must be clarified before initiating therapy. With all topical therapy for onychomycosis, it is important to treat early, treat concurrently for tinea pedis, and avoid use of nail polish so that patients have the best possible cure rates.

Onychomycosis is a fungal infection of the nail unit due to dermatophytes, yeasts, and nondermatophyte molds (NDMs). It accounts for approximately 50% of all nail disorders seen in clinical practice and is estimated to affect 10% to 12% of the US population.^1,2 Oral medications approved by the US Food and Drug Administration (FDA) include terbinafine and itraconazole, which have demonstrated good efficacy in treating onychomycosis but are associated with potential drug-drug interactions and systemic side effects.^3,4 Although liver failure associated with these drugs is rare,⁵ many patients are anxious about systemic adverse events and therefore prefer to use topical therapies for onychomycosis.

Many patients desire topical therapy but not every patient is an appropriate candidate. Patients who will likely respond well to topical therapy include those with superficial onychomycosis, distal lateral subungual onychomycosis that involves less than 50% of the nail plate surface area (without matrix involvement and a nail plate thickness less than 2 mm), and only up to 3 or 4 nails affected.⁶ In patients who have contraindications to oral therapy, topical therapy may be the only treatment option. To maximize efficacy of FDA-approved topical agents for onychomycosis therapy, patient education is of utmost importance. Failure to properly counsel the patient on proper medication application may result in decreased antifungal efficacy; poor patient compliance due to lack of improvement; and progression of disease, leading to increased onychodystrophy and pain.

Before initiating therapy, patients should be counseled that treatment with topical drugs is long, requiring daily application of the medication for 6 months for fingernails and 12 months for toenails, based on average nail growth rates (2–3 mm per month for fingernails; 1 mm per month for toenails).⁷ Patients also are advised to avoid nail polish application during the course of therapy, as clinical trials were performed without nail polish and the true efficacy with nail polish is unknown.^8-10 Because patients who have had onychomycosis for shorter durations generally have better cure rates than those who have disease for longer durations, it is prudent to initiate topical therapy as early as possible.^11,12 Treating the feet with an antifungal while treating the nails for onychomycosis further enhances efficacy.^13,14 There are 3 FDA-approved topical therapies for onychomycosis: ciclopirox nail lacquer 8%, efinaconazole solution 10%, and tavaborole solution 5%.^15-17

Ciclopirox is a hydroxypyridone with broad-spectrum antimicrobial activity against dermatophytes, NDMs, yeasts, and bacteria. Its mechanism of action is to chelate polyvalent cations, such as Fe³⁺, and inhibit fungal metal-dependent enzymes responsible for the degradation of toxic metabolites.¹⁵ Ciclopirox nail lacquer 8% was FDA approved for the treatment of onychomycosis in 1999, making it the first topical approved for this purpose. Its indication is for immunocompetent patients with mild to moderate onychomycosis (Trichophyton rubrum) without lunula involvement, with mycologic cure rates of 29% to 36% and complete cure rates of 5.5% to 8.5% (toenails).¹⁵ It is the only FDA-approved topical treatment for both fingernails and toenails. Using a brush applicator, it is applied daily to the nail plate and its undersurface, hyponychium, and 5 mm of the surrounding skin. It is important to counsel the patient to remove the lacquer from the nail plate weekly because failure to do so will result in accumulation of numerous layers of medication, such that the active drug cannot reach the site of infection (Figures 1 and 2). The nail plate also should be trimmed and filed weekly by the patient, with monthly clipping/debridement by a physician recommended.^6,15

Efinaconazole is a triazole with antifungal activity against dermatophytes, NDMs, and Candida species. Its mechanism of action is inhibition of lanosterol 14α-demethylase, an enzyme involved in the biosynthesis of ergosterol, which is a component of the fungal cell membrane. Efinaconazole solution 10% was FDA approved in June 2014 for the treatment of toenail onychomycosis due to T rubrum and Trichophyton mentagrophytes, with package insert mycologic cure rates of 53.4% to 55.2% and complete cure rates of 15.2% to 17.8%.^9,16 It is applied with a brush applicator to the nail plate, as well as its undersurface, nail folds, and hyponychium. Two drops are recommended for the great toenail and one drop for all other toenails, and no removal of the solution or debridement is required.^6,16

Tavaborole is a benzoxaborole with antifungal activity against dermatophytes, NDMs, and yeasts. Its mechanism of action is inhibition of fungal aminoacyl transfer RNA synthetase, thus impeding protein synthesis.¹⁸ Tavaborole solution 5% was FDA approved in July 2014 for the treatment of toenail onychomycosis due to T rubrum and T mentagrophytes, with mycologic cure rates of 31.1% and 35.9% and complete cure rates of 6.5% and 9.1%, respectively.^11,17 It is applied with a glass pointed-tip dropper to the nail plate, such that the entire nail is covered as well as under the nail tip. No removal of the solution or debridement is required.¹⁷

Topical therapies for onychomycosis require long treatment durations, thus excellent compliance and adherence to the treatment protocol are vital to maximize efficacy. Dermatologists who prescribe ciclopirox nail lacquer 8% should counsel patients to remove the lacquer with alcohol weekly, such that the antifungal penetrates the nail plate to reach the site of infection. Monthly debridement also must be clarified before initiating therapy. With all topical therapy for onychomycosis, it is important to treat early, treat concurrently for tinea pedis, and avoid use of nail polish so that patients have the best possible cure rates.

Onychomycosis is a fungal infection of the nail unit due to dermatophytes, yeasts, and nondermatophyte molds (NDMs). It accounts for approximately 50% of all nail disorders seen in clinical practice and is estimated to affect 10% to 12% of the US population.^1,2 Oral medications approved by the US Food and Drug Administration (FDA) include terbinafine and itraconazole, which have demonstrated good efficacy in treating onychomycosis but are associated with potential drug-drug interactions and systemic side effects.^3,4 Although liver failure associated with these drugs is rare,⁵ many patients are anxious about systemic adverse events and therefore prefer to use topical therapies for onychomycosis.

Many patients desire topical therapy but not every patient is an appropriate candidate. Patients who will likely respond well to topical therapy include those with superficial onychomycosis, distal lateral subungual onychomycosis that involves less than 50% of the nail plate surface area (without matrix involvement and a nail plate thickness less than 2 mm), and only up to 3 or 4 nails affected.⁶ In patients who have contraindications to oral therapy, topical therapy may be the only treatment option. To maximize efficacy of FDA-approved topical agents for onychomycosis therapy, patient education is of utmost importance. Failure to properly counsel the patient on proper medication application may result in decreased antifungal efficacy; poor patient compliance due to lack of improvement; and progression of disease, leading to increased onychodystrophy and pain.

Before initiating therapy, patients should be counseled that treatment with topical drugs is long, requiring daily application of the medication for 6 months for fingernails and 12 months for toenails, based on average nail growth rates (2–3 mm per month for fingernails; 1 mm per month for toenails).⁷ Patients also are advised to avoid nail polish application during the course of therapy, as clinical trials were performed without nail polish and the true efficacy with nail polish is unknown.^8-10 Because patients who have had onychomycosis for shorter durations generally have better cure rates than those who have disease for longer durations, it is prudent to initiate topical therapy as early as possible.^11,12 Treating the feet with an antifungal while treating the nails for onychomycosis further enhances efficacy.^13,14 There are 3 FDA-approved topical therapies for onychomycosis: ciclopirox nail lacquer 8%, efinaconazole solution 10%, and tavaborole solution 5%.^15-17

Ciclopirox is a hydroxypyridone with broad-spectrum antimicrobial activity against dermatophytes, NDMs, yeasts, and bacteria. Its mechanism of action is to chelate polyvalent cations, such as Fe³⁺, and inhibit fungal metal-dependent enzymes responsible for the degradation of toxic metabolites.¹⁵ Ciclopirox nail lacquer 8% was FDA approved for the treatment of onychomycosis in 1999, making it the first topical approved for this purpose. Its indication is for immunocompetent patients with mild to moderate onychomycosis (Trichophyton rubrum) without lunula involvement, with mycologic cure rates of 29% to 36% and complete cure rates of 5.5% to 8.5% (toenails).¹⁵ It is the only FDA-approved topical treatment for both fingernails and toenails. Using a brush applicator, it is applied daily to the nail plate and its undersurface, hyponychium, and 5 mm of the surrounding skin. It is important to counsel the patient to remove the lacquer from the nail plate weekly because failure to do so will result in accumulation of numerous layers of medication, such that the active drug cannot reach the site of infection (Figures 1 and 2). The nail plate also should be trimmed and filed weekly by the patient, with monthly clipping/debridement by a physician recommended.^6,15

Efinaconazole is a triazole with antifungal activity against dermatophytes, NDMs, and Candida species. Its mechanism of action is inhibition of lanosterol 14α-demethylase, an enzyme involved in the biosynthesis of ergosterol, which is a component of the fungal cell membrane. Efinaconazole solution 10% was FDA approved in June 2014 for the treatment of toenail onychomycosis due to T rubrum and Trichophyton mentagrophytes, with package insert mycologic cure rates of 53.4% to 55.2% and complete cure rates of 15.2% to 17.8%.^9,16 It is applied with a brush applicator to the nail plate, as well as its undersurface, nail folds, and hyponychium. Two drops are recommended for the great toenail and one drop for all other toenails, and no removal of the solution or debridement is required.^6,16

Tavaborole is a benzoxaborole with antifungal activity against dermatophytes, NDMs, and yeasts. Its mechanism of action is inhibition of fungal aminoacyl transfer RNA synthetase, thus impeding protein synthesis.¹⁸ Tavaborole solution 5% was FDA approved in July 2014 for the treatment of toenail onychomycosis due to T rubrum and T mentagrophytes, with mycologic cure rates of 31.1% and 35.9% and complete cure rates of 6.5% and 9.1%, respectively.^11,17 It is applied with a glass pointed-tip dropper to the nail plate, such that the entire nail is covered as well as under the nail tip. No removal of the solution or debridement is required.¹⁷

Topical therapies for onychomycosis require long treatment durations, thus excellent compliance and adherence to the treatment protocol are vital to maximize efficacy. Dermatologists who prescribe ciclopirox nail lacquer 8% should counsel patients to remove the lacquer with alcohol weekly, such that the antifungal penetrates the nail plate to reach the site of infection. Monthly debridement also must be clarified before initiating therapy. With all topical therapy for onychomycosis, it is important to treat early, treat concurrently for tinea pedis, and avoid use of nail polish so that patients have the best possible cure rates.

What does your patient need to know at the first visit?

Risk factors for onychomycosis include prior trauma, history of tinea pedis, sports activities, frequenting gyms and pools, hyperhidrosis, advancing age, diabetes mellitus, immunosuppression, smoking, and family history of onychomycosis. Toenails are involved more frequently than fingernails, and typical physical examination findings are distal and lateral nail plate onycholysis with subungual hyperkeratosis. In more severe cases, there may be nail plate thickening, crumbling, yellowing, and involvement of the nail matrix.

Because other nail conditions may resemble onychomycosis, it is imperative to confirm the diagnosis using histopathology, direct microscopy, fungal culture, and/or polymerase chain reaction on nail plate clippings or subungual debris. 

What are your go-to treatments? What are the side effects?

After laboratory confirmation, assess the patient for the severity of the infection based on the surface area of nail plate affected, nail plate thickness, involvement of the nail matrix, and number of nails affected. United States Food and Drug Administration-approved oral and topical antifungals are used first line for the treatment of onychomycosis. Devices such as lasers are approved by the US Food and Drug Administration for temporary cosmetic improvement in the appearance of the nail without eradicating the fungus.

Oral antifungals such as terbinafine, itraconazole, and fluconazole (off label) are indicated for patients with severe disease. Patients with mild to moderate disease may benefit from oral or topical antifungals such as efinaconazole, tavaborole, or ciclopirox.

I recommend terbinafine to many of my patients due to its high complete and mycological cure rates, short list of drug-drug interactions, and low incidence of side effects. Adverse reactions are uncommon, with the most common being gastrointestinal upset. While liver injury has been reported, it is exceedingly rare. Itraconazole has many important drug interactions and is contraindicated in patients with congestive heart failure. With topical antifungals, side effects are uncommon, but dermatitis, ingrown nails, and vesicles may occur.

How do you keep patients compliant with treatment?

Patients on a 3-month course of daily oral terbinafine or itraconazole for toenail onychomycosis are typically highly compliant. Compliance for patients on oral fluconazole (off label) is generally more challenging because it is dosed weekly until the nail grows out (1-1.5 years for toenails). To circumvent missed fluconazole doses, I recommend that the patient schedule quarterly visits with me and also to set a cell phone alarm as a weekly reminder to take the medication.

Because topical medications are prescribed for the toenails for a year-long course (with avoidance of nail polish during this period), I prescribe topical antifungals only to highly motivated patients. In addition, because topical antifungals are retained in the nail plate for at least several days after a month-long application, I tell my patients that if they have a big event to attend that they can take a vacation from the topical antifungal, get a pedicure, and then resume treatment after the event. 

What do you do if they refuse treatment?

In 2018, we have many options to treat onychomycosis effectively, and therapy is individualized based on the patient's severity of disease, infecting organism(s), comorbidities, concomitant medications, and preferences. If the patient's fungal nail infection is asymptomatic and not aesthetically bothersome, he/she may opt for observation rather than treatment. If the decision is observation, I recommend use of a topical antifungal on the feet and web spaces to prevent worsening of onychomycosis. 

Suggested Readings

Gupta AK, Versteeg SG. A critical review of improvement rates for laser therapy used to treat toenail onychomycosis. J Eur Acad Dermatol Venereol. 2017;31:1111-1118.

Lipner SR, Scher RK. Long-standing onychodystrophy in a young woman. JAMA. 2016;316:1915-1916.

Lipner SR, Scher RK. Onychomycosis--a small step for quality of care. Curr Med Res Opin. 2016;32:865-867.

Lipner SR, Scher RK. Onychomycosis: current and investigational therapies. Cutis. 2014;94:E21-E24.

What does your patient need to know at the first visit?

Risk factors for onychomycosis include prior trauma, history of tinea pedis, sports activities, frequenting gyms and pools, hyperhidrosis, advancing age, diabetes mellitus, immunosuppression, smoking, and family history of onychomycosis. Toenails are involved more frequently than fingernails, and typical physical examination findings are distal and lateral nail plate onycholysis with subungual hyperkeratosis. In more severe cases, there may be nail plate thickening, crumbling, yellowing, and involvement of the nail matrix.

Because other nail conditions may resemble onychomycosis, it is imperative to confirm the diagnosis using histopathology, direct microscopy, fungal culture, and/or polymerase chain reaction on nail plate clippings or subungual debris. 

What are your go-to treatments? What are the side effects?

After laboratory confirmation, assess the patient for the severity of the infection based on the surface area of nail plate affected, nail plate thickness, involvement of the nail matrix, and number of nails affected. United States Food and Drug Administration-approved oral and topical antifungals are used first line for the treatment of onychomycosis. Devices such as lasers are approved by the US Food and Drug Administration for temporary cosmetic improvement in the appearance of the nail without eradicating the fungus.

Oral antifungals such as terbinafine, itraconazole, and fluconazole (off label) are indicated for patients with severe disease. Patients with mild to moderate disease may benefit from oral or topical antifungals such as efinaconazole, tavaborole, or ciclopirox.

I recommend terbinafine to many of my patients due to its high complete and mycological cure rates, short list of drug-drug interactions, and low incidence of side effects. Adverse reactions are uncommon, with the most common being gastrointestinal upset. While liver injury has been reported, it is exceedingly rare. Itraconazole has many important drug interactions and is contraindicated in patients with congestive heart failure. With topical antifungals, side effects are uncommon, but dermatitis, ingrown nails, and vesicles may occur.

How do you keep patients compliant with treatment?

Patients on a 3-month course of daily oral terbinafine or itraconazole for toenail onychomycosis are typically highly compliant. Compliance for patients on oral fluconazole (off label) is generally more challenging because it is dosed weekly until the nail grows out (1-1.5 years for toenails). To circumvent missed fluconazole doses, I recommend that the patient schedule quarterly visits with me and also to set a cell phone alarm as a weekly reminder to take the medication.

Because topical medications are prescribed for the toenails for a year-long course (with avoidance of nail polish during this period), I prescribe topical antifungals only to highly motivated patients. In addition, because topical antifungals are retained in the nail plate for at least several days after a month-long application, I tell my patients that if they have a big event to attend that they can take a vacation from the topical antifungal, get a pedicure, and then resume treatment after the event. 

What do you do if they refuse treatment?

In 2018, we have many options to treat onychomycosis effectively, and therapy is individualized based on the patient's severity of disease, infecting organism(s), comorbidities, concomitant medications, and preferences. If the patient's fungal nail infection is asymptomatic and not aesthetically bothersome, he/she may opt for observation rather than treatment. If the decision is observation, I recommend use of a topical antifungal on the feet and web spaces to prevent worsening of onychomycosis. 

Suggested Readings

Gupta AK, Versteeg SG. A critical review of improvement rates for laser therapy used to treat toenail onychomycosis. J Eur Acad Dermatol Venereol. 2017;31:1111-1118.

Lipner SR, Scher RK. Long-standing onychodystrophy in a young woman. JAMA. 2016;316:1915-1916.

Lipner SR, Scher RK. Onychomycosis--a small step for quality of care. Curr Med Res Opin. 2016;32:865-867.

Lipner SR, Scher RK. Onychomycosis: current and investigational therapies. Cutis. 2014;94:E21-E24.

What does your patient need to know at the first visit?

Risk factors for onychomycosis include prior trauma, history of tinea pedis, sports activities, frequenting gyms and pools, hyperhidrosis, advancing age, diabetes mellitus, immunosuppression, smoking, and family history of onychomycosis. Toenails are involved more frequently than fingernails, and typical physical examination findings are distal and lateral nail plate onycholysis with subungual hyperkeratosis. In more severe cases, there may be nail plate thickening, crumbling, yellowing, and involvement of the nail matrix.

Because other nail conditions may resemble onychomycosis, it is imperative to confirm the diagnosis using histopathology, direct microscopy, fungal culture, and/or polymerase chain reaction on nail plate clippings or subungual debris. 

What are your go-to treatments? What are the side effects?

After laboratory confirmation, assess the patient for the severity of the infection based on the surface area of nail plate affected, nail plate thickness, involvement of the nail matrix, and number of nails affected. United States Food and Drug Administration-approved oral and topical antifungals are used first line for the treatment of onychomycosis. Devices such as lasers are approved by the US Food and Drug Administration for temporary cosmetic improvement in the appearance of the nail without eradicating the fungus.

Oral antifungals such as terbinafine, itraconazole, and fluconazole (off label) are indicated for patients with severe disease. Patients with mild to moderate disease may benefit from oral or topical antifungals such as efinaconazole, tavaborole, or ciclopirox.

I recommend terbinafine to many of my patients due to its high complete and mycological cure rates, short list of drug-drug interactions, and low incidence of side effects. Adverse reactions are uncommon, with the most common being gastrointestinal upset. While liver injury has been reported, it is exceedingly rare. Itraconazole has many important drug interactions and is contraindicated in patients with congestive heart failure. With topical antifungals, side effects are uncommon, but dermatitis, ingrown nails, and vesicles may occur.

How do you keep patients compliant with treatment?

Patients on a 3-month course of daily oral terbinafine or itraconazole for toenail onychomycosis are typically highly compliant. Compliance for patients on oral fluconazole (off label) is generally more challenging because it is dosed weekly until the nail grows out (1-1.5 years for toenails). To circumvent missed fluconazole doses, I recommend that the patient schedule quarterly visits with me and also to set a cell phone alarm as a weekly reminder to take the medication.

Because topical medications are prescribed for the toenails for a year-long course (with avoidance of nail polish during this period), I prescribe topical antifungals only to highly motivated patients. In addition, because topical antifungals are retained in the nail plate for at least several days after a month-long application, I tell my patients that if they have a big event to attend that they can take a vacation from the topical antifungal, get a pedicure, and then resume treatment after the event. 

What do you do if they refuse treatment?

In 2018, we have many options to treat onychomycosis effectively, and therapy is individualized based on the patient's severity of disease, infecting organism(s), comorbidities, concomitant medications, and preferences. If the patient's fungal nail infection is asymptomatic and not aesthetically bothersome, he/she may opt for observation rather than treatment. If the decision is observation, I recommend use of a topical antifungal on the feet and web spaces to prevent worsening of onychomycosis. 

Suggested Readings

Gupta AK, Versteeg SG. A critical review of improvement rates for laser therapy used to treat toenail onychomycosis. J Eur Acad Dermatol Venereol. 2017;31:1111-1118.

Lipner SR, Scher RK. Long-standing onychodystrophy in a young woman. JAMA. 2016;316:1915-1916.

Lipner SR, Scher RK. Onychomycosis--a small step for quality of care. Curr Med Res Opin. 2016;32:865-867.

Lipner SR, Scher RK. Onychomycosis: current and investigational therapies. Cutis. 2014;94:E21-E24.

Nail surgery is an important part of dermatologic training and clinical practice, both for diagnosis and treatment of nail disorders as well as benign and malignant nail tumors. Patient comfort is essential prior to the procedure and while administering local anesthetics. Effective anesthesia facilitates nail unit biopsies, excisions, and other surgical nail procedures. Pain management immediately following the procedure and during the postoperative period are equally important.

Patients who undergo nail surgery may experience anxiety due to fear of a cancer diagnosis, pain during the surgery, or disfigurement from the procedure. This anxiety may lead to increased blood pressure, a decreased pain threshold, and mental and physical discomfort.¹ A detailed explanation of the procedure itself as well as expectations following the surgery are helpful in diminishing these fears. Administration of a fast-acting benzodiazepine also may be helpful in these patients to decrease anxiety prior to the procedure.²

Attaining adequate anesthesia requires an understanding of digital anatomy, particularly innervation. Innervation of the digits is supplied by the volar and dorsal nerves, which divide into 3 branches at the distal interphalangeal joint, innervating the nail bed, the digital tip, and the pulp.³ Pacinian and Ruffini corpuscles and free-ended nociceptors activate nerve fibers that transmit pain impulses.^4,5 Local anesthetics block pain transmission by impeding voltage-gated sodium channels located at free nerve endings. Pain from anesthesia may be due to both needle insertion and fluid infiltration.

Simple measures can maximize patient comfort during digital anesthesia. Both audiovisual distraction and interpersonal interaction can help to put the patient at ease.^6,7 Application of topical anesthetic cream (1–2 hours prior to the procedure under occlusion),⁸ ice (at least 6 minutes),⁹ or an ethyl chloride spray can be applied to the nail folds prior to needle insertion to alleviate injection pain, but these methods do little for infiltration pain. Use of an ethyl chloride spray may be the preferred technique due to the rapidity of the analgesic effects (Figure).¹⁰ A vibrating massager also can be applied in close proximity to the site of needle insertion.¹¹

Proper anesthetic preparation and technique also can minimize pain during injection. Because lidocaine 1% is acidic (pH, 6.09), buffering with sodium bicarbonate 8.4% can result in decreased injection pain and faster onset of action.^6,12 Warming the anesthetic using a water bath, incubator, or autoclave can decrease pain without degradation of lidocaine or epinephrine.¹³ At a minimum, 30-gauge needles are preferred to minimize pain from needle insertion. Use of 33-gauge needles has shown benefit for injecting the face and scalp and may prove to be helpful injecting sensitive areas such as the digits.¹⁴ A slow injection technique is more comfortable for the patient, as rapid injection causes tissue distention.¹¹

The ideal anesthetic for nail surgery would have a fast onset and a long duration of action, which would allow for shorter operation time as well as alleviation of pain postprocedure and some degree of vasoconstriction to help maintain a bloodless field. Lidocaine has the fastest time of onset (<1–3 minutes) but a short duration of action (30–120 minutes) and a vasodilatory effect. Bupivacaine takes 2 to 5 minutes to take effect and has a long duration of action (120–240 minutes) but a risk for cardiotoxicity. Ropivacaine is the preferred anesthetic by some nail surgeons because of its intermediate time of onset (1–15 minutes), long duration of action (120–360 minutes), and the benefit of some vasoconstriction.^5,15 The addition of epinephrine has 2 main advantages: vasoconstriction and prolongation of anesthetic effects; the latter may help to alleviate postoperative pain. If there are no contraindications to its use (ie, severe hypertension, Raynaud phenomenon), it can be used safely in digital anesthesia without risk for ischemia or infarction.¹¹

Digital anesthesia can be achieved by infiltration or using nerve blocks. One major difference between these 2 approaches is the time of onset of anesthesia, with the former being nearly instantaneous and the latter taking up to 15 minutes.¹⁶ There also usually is more prolonged pain at the site of needle insertion with nerve blocks compared to infiltration. The type of nail surgery being performed, the digit involved, and surgeon preference will determine the anesthetic method of choice.¹⁷

Pain management immediately following the procedure and for several days after is essential. Use of a longer-acting anesthetic, such as bupivacaine or ropivacaine, will provide anesthesia for several hours. A well-padded dressing serves to absorb blood and protect the nail and distal digit from trauma, as even minor trauma can exacerbate pain and bleeding. The patient should be instructed to apply ice to the surgical site and keep the ipsilateral extremity elevated for the next 2 days to reduce edema and pain.¹⁵ Written instructions are helpful, as anxiety during and after the procedure may limit the patient’s understanding and recollection of the verbal postoperative instructions. To maximize readability of the information, the National Institutes of Health and American Medical Association recommend that the instructions be written at a fourth- to sixth-grade reading level.^18,19

A single dose of ibuprofen (400 mg) or acetaminophen (500 mg to 1 g) immediately before or after the procedure can reduce opioid use and postoperative pain.²⁰ Gabapentin (300–1200 mg) given 1 to 2 hours before surgery may be considered in patients who are at high risk for postsurgical pain.²¹ Acetaminophen or nonsteroidal anti-inflammatory drugs (eg, ibuprofen [200–400 mg]) administered every 4 to 6 hours provides considerable pain reduction postprocedure. Nonsteroidal anti-inflammatory drugs may be superior to acetaminophen for pain control²² and carry a low risk for postoperative bleeding.²³ Additionally, a combination of acetaminophen with a nonsteroidal anti-inflammatory drug for 3 doses may be more effective than either drug alone.²⁴ Some patients may require an opioid combination, such as codeine plus acetaminophen, for a short time (up to 3 days) for pain relief following surgery. Excessive pain or pain lasting than more than 3 days is not normal or expected; in these cases, patients should return to the office to rule out ischemia or infection.

It is important to implement pain-minimizing strategies for nail surgeries. Because many of these approaches are derived from other surgical specialties, well-controlled clinical trials in patients undergoing nail surgery will be necessary to improve outcomes.

Nail surgery is an important part of dermatologic training and clinical practice, both for diagnosis and treatment of nail disorders as well as benign and malignant nail tumors. Patient comfort is essential prior to the procedure and while administering local anesthetics. Effective anesthesia facilitates nail unit biopsies, excisions, and other surgical nail procedures. Pain management immediately following the procedure and during the postoperative period are equally important.

Patients who undergo nail surgery may experience anxiety due to fear of a cancer diagnosis, pain during the surgery, or disfigurement from the procedure. This anxiety may lead to increased blood pressure, a decreased pain threshold, and mental and physical discomfort.¹ A detailed explanation of the procedure itself as well as expectations following the surgery are helpful in diminishing these fears. Administration of a fast-acting benzodiazepine also may be helpful in these patients to decrease anxiety prior to the procedure.²

Attaining adequate anesthesia requires an understanding of digital anatomy, particularly innervation. Innervation of the digits is supplied by the volar and dorsal nerves, which divide into 3 branches at the distal interphalangeal joint, innervating the nail bed, the digital tip, and the pulp.³ Pacinian and Ruffini corpuscles and free-ended nociceptors activate nerve fibers that transmit pain impulses.^4,5 Local anesthetics block pain transmission by impeding voltage-gated sodium channels located at free nerve endings. Pain from anesthesia may be due to both needle insertion and fluid infiltration.

Simple measures can maximize patient comfort during digital anesthesia. Both audiovisual distraction and interpersonal interaction can help to put the patient at ease.^6,7 Application of topical anesthetic cream (1–2 hours prior to the procedure under occlusion),⁸ ice (at least 6 minutes),⁹ or an ethyl chloride spray can be applied to the nail folds prior to needle insertion to alleviate injection pain, but these methods do little for infiltration pain. Use of an ethyl chloride spray may be the preferred technique due to the rapidity of the analgesic effects (Figure).¹⁰ A vibrating massager also can be applied in close proximity to the site of needle insertion.¹¹

Proper anesthetic preparation and technique also can minimize pain during injection. Because lidocaine 1% is acidic (pH, 6.09), buffering with sodium bicarbonate 8.4% can result in decreased injection pain and faster onset of action.^6,12 Warming the anesthetic using a water bath, incubator, or autoclave can decrease pain without degradation of lidocaine or epinephrine.¹³ At a minimum, 30-gauge needles are preferred to minimize pain from needle insertion. Use of 33-gauge needles has shown benefit for injecting the face and scalp and may prove to be helpful injecting sensitive areas such as the digits.¹⁴ A slow injection technique is more comfortable for the patient, as rapid injection causes tissue distention.¹¹

The ideal anesthetic for nail surgery would have a fast onset and a long duration of action, which would allow for shorter operation time as well as alleviation of pain postprocedure and some degree of vasoconstriction to help maintain a bloodless field. Lidocaine has the fastest time of onset (<1–3 minutes) but a short duration of action (30–120 minutes) and a vasodilatory effect. Bupivacaine takes 2 to 5 minutes to take effect and has a long duration of action (120–240 minutes) but a risk for cardiotoxicity. Ropivacaine is the preferred anesthetic by some nail surgeons because of its intermediate time of onset (1–15 minutes), long duration of action (120–360 minutes), and the benefit of some vasoconstriction.^5,15 The addition of epinephrine has 2 main advantages: vasoconstriction and prolongation of anesthetic effects; the latter may help to alleviate postoperative pain. If there are no contraindications to its use (ie, severe hypertension, Raynaud phenomenon), it can be used safely in digital anesthesia without risk for ischemia or infarction.¹¹

Digital anesthesia can be achieved by infiltration or using nerve blocks. One major difference between these 2 approaches is the time of onset of anesthesia, with the former being nearly instantaneous and the latter taking up to 15 minutes.¹⁶ There also usually is more prolonged pain at the site of needle insertion with nerve blocks compared to infiltration. The type of nail surgery being performed, the digit involved, and surgeon preference will determine the anesthetic method of choice.¹⁷

Pain management immediately following the procedure and for several days after is essential. Use of a longer-acting anesthetic, such as bupivacaine or ropivacaine, will provide anesthesia for several hours. A well-padded dressing serves to absorb blood and protect the nail and distal digit from trauma, as even minor trauma can exacerbate pain and bleeding. The patient should be instructed to apply ice to the surgical site and keep the ipsilateral extremity elevated for the next 2 days to reduce edema and pain.¹⁵ Written instructions are helpful, as anxiety during and after the procedure may limit the patient’s understanding and recollection of the verbal postoperative instructions. To maximize readability of the information, the National Institutes of Health and American Medical Association recommend that the instructions be written at a fourth- to sixth-grade reading level.^18,19

A single dose of ibuprofen (400 mg) or acetaminophen (500 mg to 1 g) immediately before or after the procedure can reduce opioid use and postoperative pain.²⁰ Gabapentin (300–1200 mg) given 1 to 2 hours before surgery may be considered in patients who are at high risk for postsurgical pain.²¹ Acetaminophen or nonsteroidal anti-inflammatory drugs (eg, ibuprofen [200–400 mg]) administered every 4 to 6 hours provides considerable pain reduction postprocedure. Nonsteroidal anti-inflammatory drugs may be superior to acetaminophen for pain control²² and carry a low risk for postoperative bleeding.²³ Additionally, a combination of acetaminophen with a nonsteroidal anti-inflammatory drug for 3 doses may be more effective than either drug alone.²⁴ Some patients may require an opioid combination, such as codeine plus acetaminophen, for a short time (up to 3 days) for pain relief following surgery. Excessive pain or pain lasting than more than 3 days is not normal or expected; in these cases, patients should return to the office to rule out ischemia or infection.

It is important to implement pain-minimizing strategies for nail surgeries. Because many of these approaches are derived from other surgical specialties, well-controlled clinical trials in patients undergoing nail surgery will be necessary to improve outcomes.

Nail surgery is an important part of dermatologic training and clinical practice, both for diagnosis and treatment of nail disorders as well as benign and malignant nail tumors. Patient comfort is essential prior to the procedure and while administering local anesthetics. Effective anesthesia facilitates nail unit biopsies, excisions, and other surgical nail procedures. Pain management immediately following the procedure and during the postoperative period are equally important.

Patients who undergo nail surgery may experience anxiety due to fear of a cancer diagnosis, pain during the surgery, or disfigurement from the procedure. This anxiety may lead to increased blood pressure, a decreased pain threshold, and mental and physical discomfort.¹ A detailed explanation of the procedure itself as well as expectations following the surgery are helpful in diminishing these fears. Administration of a fast-acting benzodiazepine also may be helpful in these patients to decrease anxiety prior to the procedure.²

Attaining adequate anesthesia requires an understanding of digital anatomy, particularly innervation. Innervation of the digits is supplied by the volar and dorsal nerves, which divide into 3 branches at the distal interphalangeal joint, innervating the nail bed, the digital tip, and the pulp.³ Pacinian and Ruffini corpuscles and free-ended nociceptors activate nerve fibers that transmit pain impulses.^4,5 Local anesthetics block pain transmission by impeding voltage-gated sodium channels located at free nerve endings. Pain from anesthesia may be due to both needle insertion and fluid infiltration.

Simple measures can maximize patient comfort during digital anesthesia. Both audiovisual distraction and interpersonal interaction can help to put the patient at ease.^6,7 Application of topical anesthetic cream (1–2 hours prior to the procedure under occlusion),⁸ ice (at least 6 minutes),⁹ or an ethyl chloride spray can be applied to the nail folds prior to needle insertion to alleviate injection pain, but these methods do little for infiltration pain. Use of an ethyl chloride spray may be the preferred technique due to the rapidity of the analgesic effects (Figure).¹⁰ A vibrating massager also can be applied in close proximity to the site of needle insertion.¹¹

Proper anesthetic preparation and technique also can minimize pain during injection. Because lidocaine 1% is acidic (pH, 6.09), buffering with sodium bicarbonate 8.4% can result in decreased injection pain and faster onset of action.^6,12 Warming the anesthetic using a water bath, incubator, or autoclave can decrease pain without degradation of lidocaine or epinephrine.¹³ At a minimum, 30-gauge needles are preferred to minimize pain from needle insertion. Use of 33-gauge needles has shown benefit for injecting the face and scalp and may prove to be helpful injecting sensitive areas such as the digits.¹⁴ A slow injection technique is more comfortable for the patient, as rapid injection causes tissue distention.¹¹

The ideal anesthetic for nail surgery would have a fast onset and a long duration of action, which would allow for shorter operation time as well as alleviation of pain postprocedure and some degree of vasoconstriction to help maintain a bloodless field. Lidocaine has the fastest time of onset (<1–3 minutes) but a short duration of action (30–120 minutes) and a vasodilatory effect. Bupivacaine takes 2 to 5 minutes to take effect and has a long duration of action (120–240 minutes) but a risk for cardiotoxicity. Ropivacaine is the preferred anesthetic by some nail surgeons because of its intermediate time of onset (1–15 minutes), long duration of action (120–360 minutes), and the benefit of some vasoconstriction.^5,15 The addition of epinephrine has 2 main advantages: vasoconstriction and prolongation of anesthetic effects; the latter may help to alleviate postoperative pain. If there are no contraindications to its use (ie, severe hypertension, Raynaud phenomenon), it can be used safely in digital anesthesia without risk for ischemia or infarction.¹¹

Digital anesthesia can be achieved by infiltration or using nerve blocks. One major difference between these 2 approaches is the time of onset of anesthesia, with the former being nearly instantaneous and the latter taking up to 15 minutes.¹⁶ There also usually is more prolonged pain at the site of needle insertion with nerve blocks compared to infiltration. The type of nail surgery being performed, the digit involved, and surgeon preference will determine the anesthetic method of choice.¹⁷

Pain management immediately following the procedure and for several days after is essential. Use of a longer-acting anesthetic, such as bupivacaine or ropivacaine, will provide anesthesia for several hours. A well-padded dressing serves to absorb blood and protect the nail and distal digit from trauma, as even minor trauma can exacerbate pain and bleeding. The patient should be instructed to apply ice to the surgical site and keep the ipsilateral extremity elevated for the next 2 days to reduce edema and pain.¹⁵ Written instructions are helpful, as anxiety during and after the procedure may limit the patient’s understanding and recollection of the verbal postoperative instructions. To maximize readability of the information, the National Institutes of Health and American Medical Association recommend that the instructions be written at a fourth- to sixth-grade reading level.^18,19

A single dose of ibuprofen (400 mg) or acetaminophen (500 mg to 1 g) immediately before or after the procedure can reduce opioid use and postoperative pain.²⁰ Gabapentin (300–1200 mg) given 1 to 2 hours before surgery may be considered in patients who are at high risk for postsurgical pain.²¹ Acetaminophen or nonsteroidal anti-inflammatory drugs (eg, ibuprofen [200–400 mg]) administered every 4 to 6 hours provides considerable pain reduction postprocedure. Nonsteroidal anti-inflammatory drugs may be superior to acetaminophen for pain control²² and carry a low risk for postoperative bleeding.²³ Additionally, a combination of acetaminophen with a nonsteroidal anti-inflammatory drug for 3 doses may be more effective than either drug alone.²⁴ Some patients may require an opioid combination, such as codeine plus acetaminophen, for a short time (up to 3 days) for pain relief following surgery. Excessive pain or pain lasting than more than 3 days is not normal or expected; in these cases, patients should return to the office to rule out ischemia or infection.

It is important to implement pain-minimizing strategies for nail surgeries. Because many of these approaches are derived from other surgical specialties, well-controlled clinical trials in patients undergoing nail surgery will be necessary to improve outcomes.