Delayed post-traumatic alopecia of the dorso-lumbar area following a road accident in a cat without pelvic fracture.

An 11-month-old female, neutered domestic short-haired cat was presented for non-pruritic alopecia of the dorso-lumbar area which had appeared 1 month after a road accident. After the trauma, a fracture of the left hind limb was demonstrated without dermatological lesions on the dorso-lumbar area. One month later, hair loss was observed in this area. Four months later, clinical examination revealed dorso-lumbar alopecia. Histopathological findings included an absence of all adnexae, a mild fibroplasia and fibrosis without oriented collagen deposition, individual to coalescing pyogranulomas at the dermo-hypodermal junction and a moderately stenotic hypodermal artery. Clinical history, physical examination and histopathological findings were compatible with post-traumatic dorso-lumbar alopecia. Special features of this case include the location of the fracture and the more developed histopathological lesions with pyogranulomas at the dermo-hypodermal junction, the absence of hair follicles and a stenosing arteriopathy.