INTRODUCTION
Alopecias can be broadly categorized as scarring (cicatricial) or non-scarring. Some primary scarring alopecias may be susceptible to the appearance of new lesions in previously uninvolved areas following trauma, known as koebnerization, the Koebner phenomenon, or an isomorphic reaction.1 Treatments for scarring alopecias vary by diagnosis and include topical, intralesional, systemic, and surgical therapies. Given the procedural nature of many of these interventions and an underlying predisposition towards koebnerization, there may be concern for disease exacerbation. Furthermore, risk of koebnerization may be observed following face or scalp interventions, including elective cosmetic procedures or trauma-inducing hairstyling techniques.
Herein, we summarize the literature regarding risks of procedures in potentially koebnerizing alopecias, and provide additional expert insight to aid hair restoration and cosmetic practice in this challenging patient population. We will focus on primary scarring alopecias and divide our discussion by procedure. The information provided is summarized in Table 1.
Herein, we summarize the literature regarding risks of procedures in potentially koebnerizing alopecias, and provide additional expert insight to aid hair restoration and cosmetic practice in this challenging patient population. We will focus on primary scarring alopecias and divide our discussion by procedure. The information provided is summarized in Table 1.
MATERIALS AND METHODS
A comprehensive literature review was performed, using keywords for complications in cicatricial alopecias combined with those for common face or scalp procedures to identify articles describing procedure-induced koebnerization or disease reactivation in scarring alopecias. Publications from 1970 to 2020 were searched using PubMed (US National Library of Medicine) and Google Scholar (https://scholar.google.com/).
Procedures With Reported Risk of Disease Precipitation or Keobnerization
Hair Transplant
Hair transplantation (HT) can be used for an array of alopecias. HT involves harvesting hair from an unaffected donor site through follicular unit strip surgery (FUSS) or follicular unit extraction (FUE), and transplanting the hair follicles to the recipient site. Factors that influence the technique used are patient dependent and include degree and type of hair loss, laxity of the occipital scalp donor site, vascular supply, patient hair density and desired hair length post-procedure. When appropriate, FUE is typically the gold standard for HT due to the ability of assessing individual hair follicles and no required suturing.2 In scarring alopecias with smaller areas of hair loss, FUE is superior to FUSS because it yields fewer follicular units and theoretically causes less trauma. While, to our knowledge, no studies have been performed determining the optimal time period between scarring alopecia disease quiescence and hair transplantation
Procedures With Reported Risk of Disease Precipitation or Keobnerization
Hair Transplant
Hair transplantation (HT) can be used for an array of alopecias. HT involves harvesting hair from an unaffected donor site through follicular unit strip surgery (FUSS) or follicular unit extraction (FUE), and transplanting the hair follicles to the recipient site. Factors that influence the technique used are patient dependent and include degree and type of hair loss, laxity of the occipital scalp donor site, vascular supply, patient hair density and desired hair length post-procedure. When appropriate, FUE is typically the gold standard for HT due to the ability of assessing individual hair follicles and no required suturing.2 In scarring alopecias with smaller areas of hair loss, FUE is superior to FUSS because it yields fewer follicular units and theoretically causes less trauma. While, to our knowledge, no studies have been performed determining the optimal time period between scarring alopecia disease quiescence and hair transplantation
