[Free medial sural artery perforator flap for reconstruction of hand defects].

Objective: Defect reconstruction of the hand by means of the free medial sural artery perforator (MSAP) flap.

Indications: Reconstruction of full-thickness defects on the hand with a thin non-bulky flap in cases of exposure of functional structures or in combination with simultaneous osteosynthetic procedures.

Contraindications: Prior surgery at the donor site or progressive peripheral artery occlusive disease. Defect size that exceeds the maximum width of the free MSAP flap for primary closure of the donor site. Lack of patient consent or compliance.

Surgical technique: Suitable perforators are identified through a medial incision on the calf. The vascular pedicle is then completely followed subfascially along the gastrocnemius muscle until its source vessel the medial sural artery is reached. Subsequently, the flap design is adapted to the perforator anatomy and the flap is completely elevated. Indocyanine green fluorescence angiography can be used to identify the size of the reliable angiosome.

Postoperative management: Close monitoring of the flap is required for the first 48 hours after surgery. Anticoagulation with low-molecular weight heparin should be administered for thrombosis prophylaxis. The hand can be mobilized on the first day after surgery.

Results: Between May 2017 and March 2022 a total of 16 free MSAP flaps were carried out for hand defect reconstruction. All donor sites were primarily closed. The reconstruction was successful in all cases. In one patient venous thrombosis occurred postoperatively, which was successfully revised. In two flaps, surgical hematoma evacuation was necessary within 24 hours after surgery. Complications or wound healing disorders at the donor site were not observed.