Preoperative criteria for hallux valgus surgery and use of convergent angled base wedge osteotomy.

A discussion is presented about objective correction criteria for hallux abducto valgus surgery. A historical review of commonly used procedures performed for correction at various levels of first ray deformity is related. Based on ideal criteria for base wedge osteotomies, a new template and procedure for base wedge osteotomies derived from computer-augmented graphics is described in detail. This procedure has been referred to as a convergent angled osteotomy (CAO) and effectively reduces the metatarsus primus adductus angle with minimal loss of length, cortex to cortex apposition in closure, relative lengthening with plantarflexion if desired, and a capacity for very stable rigid internal fixation that optimizes recovery from base wedge reduction. Case histories are also presented.