Koebner Phenomenon Psoriasis after Right Ankle Free Flap Reconstruction.

Isomorphic cutaneous lesion formation in response to trauma in patients with prior cutaneous disease is known as the Koebner phenomenon. To our knowledge, there are no reports of the phenomenon occurring after lower extremity flap reconstruction. A 24-year-old male with no significant medical history underwent right ankle reconstruction using an anterolateral thigh flap following wide excision of a low-grade sarcoma. His recovery was mostly uneventful; however, 6 months later, he developed well-demarcated, erythematous plaques with white scales over both the flap and donor sites. The dermatology department diagnosed him with plaque psoriasis attributed to Koebnerization. Topical corticosteroids were prescribed and resulted in complete resolution within 2 days. At his 8-month follow-up, all surgical sites had healed with no evidence of recurrence. This case highlights a rare occurrence of the Koebner phenomenon following free flap reconstruction in a patient without prior personal or familial history of psoriasis. Early detection and treatment of postoperative dermatoses in partnership with dermatology is crucial to avoiding unnecessary intervention and achieving successful outcomes without complications.