Anatomical Basis Of The Flap Based On The Dorsal Perforatorsof The Plantar Artery

Objective By means of microscopic dissection and vascular latex perfusion, we had mainly investigated the morphological features of the dorsal perforators of plantar artery which included the first plantar metatarsal artery and the lateral plantar artery, and the dorsal cutaneous nerve and the vein of the foot. We wanted to accomplish two objectives: ①To provide anatomic basis for harvesting the perforator flap of the plantar artery for reconstruction of soft tissue defects on the forefoot; ②To enrich theoretical basis for microsurgery. Methods ⑴ 30 embalmed lower limbs of adult cadavers were used for the anatomic study, they were all perfused with red latex. ①Followings were observed by microsurgical techniques:A. The origins、courses、branches and distributions of the perforators of plantar artery which included the first plantar metatarsal artery and the lateral plantar artery; B. the courses and distributions of the dorsal cutaneous nerve and the vein of the foot; C. the anastomoses between these perforator arteries and nutrient vessels of the dorsal cutaneous nerve and the vein of the foot four sides of fresh specimen were used for designing and performing simulated operations. ②Measuring: The length, diameter of the dorsal perforators of plantar artery; the diameter of the dorsal cutaneous nerve and the vein of the foot. ⑵ 4 cast specimens was used for corroboration of vascular distribution. ⑶simulated operation was performed on another 4 fresh specimens. Results ①The perforators of plantar artery: A.The perforator of the first plantar metatarsal artery: The perforator of the first plantar metatarsal artery passed through the space between the tendon the abductor hallucis and the first metatarsal bone, and its entry point into the deep fascia was located(2.3±0.7)cm proximal to the first metatarsophalangeal joint.The perforator anastomosed with either the medial tarsal artery, the medial anterior malleolus artery or the branch of the medial plantar artery on the superior margin of the abductor hallucis, forming a longitudinal arterial chain, through which small branches were given off to the skin of the medial aspect of the foot. The perforator was(1.1±0.2)mm in diameter and(3.2±0.2)cm in length. B. The medial artery of the hallux passed forward in the fascia between the abductor hallucis tendon and the first metatarsal bone, emerged into the superficial layer 2.2 ± 0.2 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; C. The perforator of the lateral plantar artery of the fifth metatarsal bone was the consistent branch of the external plantar metatarsal artery at the tuberosity of the fifth metatarsal bone, which has a branch at the base and head of the fifth metatarsal bone, respectively.They traveled at the medial aspect of the fifth metatarsal bone, and emerged superficially to the lateral aspect of the foot through the space between the two ends of the fifth metatarsal bone and the lateral group of the plantar muscle. They anastomosed with lateral tarsal artery and the fourth dorsal phalangeal artery. The outer caliber of the perforator of the base of metatarsal and the head of metatarsal were(1.3±0.2) mm and(0.9±0.3) mm respectively, the length of the stem were(2.6±0.3)cm and(3.8±0.5)cm respectively. ②The dorsal cutaneous nerve and the vein of the foot: A. The courses and distributions of the medial cutaneous nerve and the vein of the foot: 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; B. The courses and distributions of the lateral cutaneous nerve and the vein of the foot: The lateral dorsal cutaneous nerve of foot was the direct continuation of the trunk, and coursed along with the lateral vein of the foot, innervating lateral aspect of the dorsal foot and the lateral skin of the fifth toe; Nutritional vessels of the lateral dorsal cutaneous nerve of the foot and the lateral vein of the foot were of multiple segments and multiple origins. The perforator of the lateral plantar artery was relatively consistent in position, emerging superficially between the fifth metatarsal bone and lateral group of muscles of the fifth phalange. It gave off minute branches to anastomose with longitudinal nutritional vascular plexus of lateral dorsal superficial vein the foot. Conclusion ①we observed clear anastomoses between the dorsal perforators of the plantar artery and nutrient vessels of the dorsal cutaneous nerve and the vein of the foot, which can serve as the anatomical basis for planning of four new flaps: the flap based on the perforator of the first plantar metatarsal artery, the distally based venocutaneous flap on the medial plantar artery of the hallux with medial plantar vein and nutrient vessels, the flap based on the perforator of the lateral plantar artery of the fifth metatarsal bone and the perforator-pedicled flap with nutritional vessels of the lateral dorsal cutaneous nerve and the lateral vein of the foot. All these four flaps can be used to repair soft-tissue defects around forefoot; ②These flaps can be designed and maneuvered easily and flexibly, which are new additions to method used for repairing soft-tissue defects around forefoot.