Osteotomía oblicua distal del primer metatarsiano en la cirugía del hallux rigidus. Valoración radiológica del descenso y acortamiento

Abstract

Distal first metatarsal osteotomies have been indicated in the surgical treatment of mild to moderate hallux rigidus. Its purpose is to decrease the metatarsal head but at the expense of a shortening of the same, which can sometimes produce transfer metatarsalgia. In our center we perform a modification of an oblique distal osteotomy, in order to control and prevent excessive shortening of the first metatarsal. The aim of this study is to perform a radiographic evaluation of the decrease and shortening made with this technique.We reviewed 32 cases (27 patients) undergoing hallux rigidus distal metatarsal osteotomy with no other metatarsal osteotomies associated with a year minimum follow-up. The distal osteotomy consists on a first oblique cut and it starts distally on the dorsum of the first metatarsal head with a variable angle of 10–30°; and second dorsal perpendicular cut to complete the osteotomy. The hallux rigidus were classified according to Coughlin and Shurnas. In the preoperative and postoperative radiographs at one year follow-up the intermetatarsal angle (IMTA), metatarsal-phalangeal angle (MTPA), shortening and lowering of the first metatarsal were assessed.3 cases were grade I, 10 as II and 19 were classified as III. The IMTA and MTPA were respectively 9.78° and 17.° preoperatively and 5.88° and 4.91° per year. The average shortening was 3.66 mm and the lowering 1.91mm.This modified osteotomy looks for a three-dimensional reconstruction in the treatment of hallux rigidus. The advantages are to be a stable extraarticular osteotomy, which allows properly lowering the first metatarsal head with controlled shortening of the radius, giving a rotational stability to the metatarsal head.