Angular measurements in the evaluation of hallux valgus deformities: A report of the ad hoc committee of the American Orthopaedic Foot & Ankle Society on Angular Measurements

This committee recommends that for all oral and written publications on hallux valgus deformities, the authors and presenters define the methods of measurement. We recommend that if authors need to deviate from the standardized methods described herein, the modifications in the measurement methods and rationale should be clearly described. We recommend that second metatarsal reference points be placed 1 - 2 cm proximal to the distal articular surface and 1 - 2 distal to the proximal articular surface. We recommend thatproximal phalanx reference points be placed 1/2 - 1 cm proximal and distal to the articular surface. We recommend that the first metatarsal reference points be located in the metaphyseal/diaphyseal region 1 - 2 cm proximal to the distal articular surface and 1 - 2 diatl to the proximal articular surface. For distal osteotomies, We recommend dual measurements using a center-of-head technique (using a Mose sphere and a standard protractor for the distal reference point) and metaphyseal/diaphyseal reference points for the first metatarsal axis. The exact same proximal reference point is used regardless of the location of the distal reference point.