Outcomes of a Stepcut Lengthening Calcaneal Osteotomy for Adult-Acquired Flatfoot Deformity.

Abstract

Lateral column lengthening is used to correct abduction deformity at the midfoot and improve talar head coverage in patients with flatfoot deformity. It was our hypothesis that following a stepcut lengthening calcaneal osteotomy (SLCO), patients would have adequate correction of the deformity, a high union rate of the osteotomy, and improvement in clinical outcome scores. We retrospectively reviewed 37 consecutive patients who underwent SLCO for the treatment of stage IIB flatfoot deformity with a minimum 2-year follow-up. Deformity correction was assessed using preoperative and postoperative weight-bearing radiographs. Healing of the osteotomy was assessed by computed tomography. Clinical outcomes included the FAOS and SF-36 questionnaires. The Wilcoxon signed-rank test was used to compare clinical outcome scores. An alpha level of .05 was deemed statistically significant. Healing of the osteotomy occurred at a mean of 7.7 weeks postoperatively. The talonavicular (TN) coverage angle improved from 34.0 to 8.8 (P < .001), the percentage of TN uncoverage improved from 40.9% to 17.7% (P < .001), and the TN incongruency angle improved from 68.1 to 8.7 (P < .001). In addition, there was an improvement in FAOS pain (P < .001), daily activities (P < .001), sport activities (P = .006), and quality of life scores (P < .001). Overall SF-36 scores also showed improvement postoperatively (P < .001). There was no incidence of delayed union, nonunion, or graft collapse. Following SLCO, patients demonstrated excellent healing, good correction of the deformity, and improvement in clinical outcomes scores. The SLCO is an alternative to the Evans osteotomy for lateral column lengthening. Level IV, retrospective case review.