Traction Alopecia: Mechanical and Traumatic Hair Loss

Traction alopecia is a form of mechanical, traumatic hair loss that is usually mild and chronic, often resulting from hairstyles that involve tight braiding or banding of the hair. It is most common among African-American girls but can affect individuals of all races. The condition can initially cause temporary hair loss with possible regrowth, but if excessive traction continues for years, it may lead to permanent hair loss. Histologically, acute traction alopecia shows an increase in catagen/telogen hairs and normal follicular numbers, while end-stage disease is characterized by a marked reduction in the total number of terminal hairs, with vellus hairs remaining in normal numbers and no significant inflammation. The document suggests that traction alopecia is not solely caused by mechanical factors and that an immune-mediated mechanism is unlikely in its pathogenesis. The histological findings differ between early, reversible stages and permanent, "burnt out" stages of the condition.