The Reverse Biceps Femoris Muscle Flap: An Alternative Option for Soft-tissue Coverage Around the Popliteal Fossa

Soft-tissue reconstruction around the popliteal fossa is challenging, particularly when traditional local flap options are unavailable due to trauma or anatomic constraints. We report the case of an 81-year-old woman who sustained Gustilo-Anderson type IIIB distal femoral and tibial plateau fractures with knee dislocation and soft-tissue degloving. Following initial management with a knee-spanning external fixation and a lateral gastrocnemius flap, she developed a pressure wound over the lateral femoral condyle. She underwent knee arthrodesis with a joint-spanning intramedullary nail and soft-tissue coverage with a distally based transposition muscle flap of the long head of the biceps femoris. This case demonstrated the clinical use of the biceps femoris long head based on its anastomotic connection with the short head. This approach provided a valuable option for soft-tissue reconstruction around the popliteal fossa when traditional muscle or perforator flaps are not feasible.