Anatomic basis of the distally based venocutaneous flap on the medial plantar artery of the hallux with medial plantar vein and nutrient vessels: a cadaveric dissection

This study aims to identify a repair procedure for ulcers or defect of the forefoot region. The general distribution and variation of the vascular anatomy of the distally based venocutaneous flap on the medial plantar artery of the hallux with medial plantar vein and nutrient vessels were investigated. This study especially focused on the vascularization of the medial side of the foot and the determination of the contribution of the nutrient vessels of medial plantar vein and medial dorsal cutaneous nerve to flap viability. Experiments were conducted to obtain information for operating procedures and to understand the vascular reliability of the flap.

Thirty cadavers were available for this anatomical study after arterial injection. The tuberosity of the fifth metatarsal bone was adopted as the anatomical landmark. Microdissection was conducted under a microscope, and details of the course and distribution of the medial plantar vein and the communication of the medial plantar artery of the hallux with the fascial vascular network surrounding the medial plantar vein were recorded. The flap-raising procedure was performed in a fresh cadaver specimen.

The medial plantar vein was incorporated by the medial end of the dorsal pedal vein arch and medial dorsal vein of the hallux around the first metatarsal–medial cuneiform joint. It traveled along the medial margin of the foot and drained into the great saphenous vein at the level of the medial malleolar. The outer diameter of the nerve at the intermalleolar line was 3.2 ± 0.5 mm. These nutrifying arteries to the medial plantar vein were present segmentally and mainly came from the medial plantar artery of the hallux, which traveled forward in the fascia between the abductor hallucis tendon and the first metatarsal bone, emerged into the superficial layer 2.2 ± 0.7 cm proximal to the first metatarsophalangeal joint, and gave off many minute branches. These branches communicated with the fascial vascular network surrounding the medial plantar vein, supplying the fascia and integument of the medial foot.

Reliable venocutaneous flap with medial plantar vein and nutrient vessel flaps can be raised based solely on the perforator of the medial plantar artery of the hallux. This flap should be considered as a preferential way to reconstruct soft-tissue defects of the forefoot.