Instructional Course Lectures, The American Academy of Orthopaedic Surgeons - Hallux Valgus*†

Hallux valgus occurs with lateral deviation of the great toe and medial deviation of the first metatarsal. Commonly, the deformity is characterized by progressive subluxation of the first metatarsophalangeal joint (Figs. 1-A, 1-B, and 1-C). Occasionally, there is a static deformity due to valgus angulation of the distal articular surface of the first metatarsal or the proximal phalangeal articular surface (Fig. 2). Figs. 1-A, 1-B, and 1-C: Radiographs demonstrating the different degrees of a hallux valgus deformity. The arrow indicate the direction of the subluxation, and the arrowheads indicate the extent of the joint surface. Fig. 1-A: A mild hallux valgus deformity with subluxation of the first metatarsophalangeal joint. The hallux valgus angle is 19 degrees, the first-second intermetatarsal angle is 10 degrees, and there is less than 50 per cent (mild) subluxation of the sesamoids. Fig. 1-B: Moderate hallux valgus deformity with subluxation of the first metatarsophalangeal joint. The hallux valgus angle is 30 degrees, the first-second intermetatarsal angle is 14 degrees, and there is 50 to 75 per cent (moderate) subluxation of the sesamoids. Fig. 1-C: A severe, recurrent hallux valgus deformity with severe subluxation of the first metatarsophalangeal joint. The hallux valgus angle is 50 degrees, the intermetatarsal angle is 17 degrees, and there is more than 75 per cent (severe) subluxation of the sesamoids. The second metatarsophalangeal joint is dislocated. Radiograph of a foot with moderate hallux valgus deformity without subluxation of the first metatarsophalangeal joint. The hallux valgus is due mainly to 25 degrees of valgus angulation of the distal articular surface of the metatarsal. A sagittal groove (or sulcus) has developed medial to the articular surface. There is a prominent medial eminence. The dotted line indicates the medial and lateral extent of the distal articular surface of the metatarsal. Hallux valgus …