Incidence of nonunion of the unfixated, isolated evans calcaneal osteotomy: a systematic review

Abstract

The Evans calcaneal osteotomy is frequently implemented in flatfoot reconstructive surgery for correction of planar deformity. Rigid fixation across an osteotomy is a documented, accepted technique to gain stability. However, since the original description of this osteotomy, which involved no internal fixation, debate has existed regarding the necessity of fixation. Conventional wisdom suggests that the nonunion rate would increase with an unfixated osteotomy. Thus, in an effort to determine the incidence of nonunion of the unfixated, isolated Evans calcaneal osteotomy, we conducted a systematic review. Studies were eligible for inclusion only if they included the following: the nonunion rate for unfixated, isolated Evans calcaneal osteotomy, follow-up of at least 1 year and a sample size of at least 5 feet. After considering all potentially eligible studies, 2 evidence-based medicine level 2 and 3 evidence-based medicine level 3 studies met our inclusion criteria. A total of 73 feet, with a weighted mean age of 22.6 years, were included. The weighted mean follow-up of the included studies was 3.6 years. A total of 1 nonunion (1.4%) was reported. The results of our systematic review revealed an acceptably low rate of nonunion for the unfixated, isolated Evans calcaneal osteotomy. However, considering the limited data available, additional prospective investigations are warranted to further validate the nonunion rate with this technique.