Anterolateral leg alopecia
The etiology and pathophysiology of anterolateral leg alopecia remain unclear. Although anterolateral leg alopecia and male pattern baldness may occur concurrently, it has been demonstrated that there exists no statistically significant relationship between the two. While it has long been hypothesized that said condition may be occasioned by trauma (such as rubbing), anterolateral leg alopecia lacks the truncated hairs and follicular hyperkeratosis associated with trauma; skin affected by anterolateral leg alopecia is largely unremarkable but for the lack of hair over affected areas. Research has yet to demonstrate any link between anterolateral leg alopecia and atherosclerotic, rheumatologic, or endocrine disorders. Thus, causal factors for anterolateral leg alopecia have yet to be identified.
L65.9 – Nonscarring hair loss, unspecified
201142005 – Peroneal alopecia
- Alopecia areata – The presence of exclamation point hairs and involvement of sites other than the legs are suggestive of alopecia areata rather than anterolateral leg alopecia. Biopsy can further differentiate the two pathologies.
- Peripheral artery disease – Hair loss is not sharply demarcated and is associated with shiny-appearing skin.
- Telogen effluvium – Hair loss is diffuse and not localized.
- Secondary syphilis – Results in diffuse patchy alopecia, including the scalp, where it has a "moth-eaten" appearance.
- Trauma occasioned by tight pants or socks – The distribution of hair loss is limited to areas overlain with tight clothing, and skin demonstrates histological changes consistent with trauma.
- Follicular mucinosis – While this typically presents with erythematous papules or plaques, these findings may be subtle, and a patchy nonscarring alopecia may be the most overt clinical feature.