The Green-Watermann procedure: geometric analysis and preoperative radiographic template technique.

The Green-Watermann procedure is indicated as surgical treatment of hallux limitus. The procedure requires five first metatarsal osteotomies, all of which interact to achieve the final surgical outcome. It is the unique interaction of each osteotomy that creates first metatarsal shortening, capital fragment plantar transposition, capital fragment lateral transposition, and proximal articular set angle (P.A.S.A.) correction. The geometry of the Green-Watermann procedure is reviewed. A preoperative radiographic templating technique is provided.