Austin's horizontal V-shaped sliding osteotomy of the metatarsal head [Chevron-osteotomy) in the treatment of hallux valgus

Abstract

From 1983 to 1995, 1587 patients suffering from hallux abductovalgus were treated with the Austin bunionectomy. The operation consists of a medial exostosis removal, a V-shaped laterally directed displacement osteotomy of the metatarsal head, lateral release and medial reefing of the capsulo-ligamentous structures. Lateral transposition is facilitated by performing a sufficient lateral release consisting of dissection of the lateral metatarsophalangeal ligament and separation of the adductor tendon from the base of the phalanx and the lateral sesamoid. In the case of intermetatarsal angles greater than 15 degrees, the metatarsal-sesamoid ligament is also severed just above the lateral sesamoid. The periosteum is stripped in a limited fashion dorsally and toward the plantar, leaving its insertion at the metatarsal head intact. After this procedure, reposition of the metatarsal head onto the sesamoids is usually possible and is maintained by reconstruction of the medial metatarsal-sesamoid ligament. In the author's own research material, metatarsophalangeal angles larger than 50 degrees and intermetatarsal angles of over 20 degrees could be corrected. Pronation of the toe is usually corrected by tenotomy of the abductor tendon near the base of the phalanx. Avascular necrosis is extremely rare with a careful operative technique. In our extensive research material, four cases of AVN were recognized. Provided there is free motion of the joint (60-0-20), mild radiological signs of osteoarthritis are no contraindication for the operation. Even in the aged, good results can be achieved provided there are no trophic problems. The Austin bunionectomy has proved to be a versatile method for treating bunion problems. The possibility of transposing the metatarsal head laterally, toward the plantar, proximally and distally by altering the direction of the osteotomy, as well as tilting it medially or laterally, has made this osteotomy an invaluable tool for addressing various problems in bunion surgery.