Radiographic Outcomes in the Treatment of Type II Adult Acquired Flatfoot Deformity Following Lateral Column Lengthening with a Titanium Wedge versus Autograft or Allograft

Abstract

Category: Midfoot/Forefoot Introduction/Purpose: Lateral column lengthening (LCL) is a surgical procedure used to manage forefoot abduction occurring in patients with stage IIB Adult Acquired Flat Foot Deformity (AAFD). This procedure utilizes an opening wedge osteotomy of the calcaneus which is then filled with autograft, allograft, or a titanium wedge. The primary aim of this study was to compare the radiographic outcomes of these different bone substitutes in the setting of stage IIB AAFD with the use of LCL. Methods: All patients who underwent LCL from October 2008 until October 2018 were retrospectively reviewed. Preoperative weight bearing radiographs, initial postoperative radiographs and 1-year weight bearing radiographs were reviewed. The following radiographic measurements were recorded: talonavicular uncoverage angle, incongruency angle, and calcaneal pitch. Results: A total of 44 patients were included in our study. The mean age of the cohort was 54 (range 18-74). The study cohort was divided into two groups. There were 17 (38.7%) patients that received a titanium wedge and 27 (61.5%) that received autograft or allograft. Patients that underwent LCL with the autograft/allograft group were significantly older (p=0.006). Patients who underwent LCL with a titanium wedge had a significantly higher preoperative talonavicular angle (p=0.013). There were no significant differences in post-operative talonavicular uncoverage angle, incongruency angle or calcaneal pitch at 6 months or 1 year. Conclusion: Adult acquired flat foot deformity is a difficult disorder to treat surgically. Lateral column lengthening is a common surgical procedure used to treat forefoot abduction that occurs. Our results show that at 6 months and 1 year no radiographic difference exists between autograft/allograft bone substitutes versus titanium wedge in LCL. Future research should evaluate the differences in patient reported outcomes between autograft/allograft versus titanium wedge bone substitutes.