Clarification of the anatomic definition of the bunion deformity.

Evolution of the terminology applied to the bunion deformity has progressed in parallel with our changing understanding of the deformity itself. Along this path of progression have been multiple terms, sometimes with multiple meanings. Hallux valgus and metatarsus primus varus are 2 of the most common terms for the deformity. Although commonly used, these descriptors can have multiple meanings, and inconsistencies in interpretation can lead to confusion. We propose a more detailed terminology to provide a more accurate description of the entire bunion deformity in 3 planes and for both the hallux and the metatarsal component of the deformity. The term we propose is hallux abducto valgus with metatarsus primus adducto valgus. An accurate understanding of the multiplanar position of the deformed foot is important for planning deformity correction. The descriptors in the terminology proposed will keep in the forefront the aspects of correction required for the first ray and hallux to be returned to an anatomically correct position.