Short- to Intermediate-Term Radiographic Outcomes Following Cotton Osteotomy

Abstract

The cotton osteotomy or the medial cuneiform opening wedge osteotomy has been a common adjunct procedure in flatfoot reconstruction to correct for forefoot varus or a dorsiflexed first ray. The main goal of the study is to retrospectively review outcomes specifically in the short-intermediate term for the cotton osteotomy. The medical records of a single foot and ankle surgeon (PRB) were reviewed for patients who met inclusion and exclusion criteria. The study period was from January 2006 to October 2018. The analysis was performed using information obtained from chart-review to examine union and complication rates, as well as changes in the cuneiform articular angle based on graft size and type. A total of 71 feet in 61 patients underwent cotton osteotomies for flatfoot reconstruction. Overall complication rate was 5.6% (4/71) with 2 nonunions (2/47) in those that had radiographic follow-up of greater than 9 months. Change in cuneiform articular angle (CAA) showed 0.91° of correction per 1-millimeter increase in graft wedge size from preoperative to 3 weeks. Change for anterior-posterior medial cuneiform bisection dorsal length (AP length) was 0.70 mm per 1 mm of graft used from preoperative to 3 weeks. 6 weeks to 10 weeks showed statistically significant changes in the CAA (p=.01) and the AP length (p=.002). The cotton osteotomy showed statistically significant radiographic loss of correction between the 6- and 10-week time points when patients were allowed to begin weightbearing. Metal grafts may provide maintenance of correction which warrants future studies on their efficacy.