Ultrasound analyses, anatomical considerations, and clinical experience with the peroneus brevis muscle flap.

This ultrasound study investigated the frequency, location, and diameter of segmental blood supply of 34 lower legs in relation to muscle size. Furthermore, we investigated the possibilities and constraints of distally pedicled peroneus brevis muscle flaps, which allow defect coverage down to the medial as well as the lateral ankle. In the proximal part of the peroneus brevis muscle, blood is supplied by branches from the anterior tibial artery that perforate the anterior intermuscular septum; in the distal part of the muscle, blood is supplied by branches from the peroneal artery that perforate the posterior intermuscular septum. All lower legs showed at least one perforating vessel penetrating the posterior intermuscular septum. In all, 32.4% of the legs showed two perforators and 17.6% three perforators. The average position of the most distal perforator was 4.8cm proximal to the tip of the malleolus lateralis. Based on this blood supply, muscle tissue measuring up to 15-20cm can be harvested and rotated by 180° to cover defects of the lower ankle. Our ultrasound study is supplemented by an anatomical dissection and two clinical cases of successful defect coverage with the distally pedicled peroneus muscle flap.