Impact of Diabetes on Outcome of Total Ankle Replacement

Background: As the incidence of diabetes mellitus (DM) grows, managing patients with diabetes and concomitant ankle arthritis poses a challenging clinical dilemma. While diabetes is known to be a risk factor for complications relating to open reduction and internal fixation of ankle fractures, it is unclear if DM is a risk factor for negative outcomes after total ankle replacement (TAR). Methods: We retrospectively identified a consecutive series of 813 primary TARs performed between 2002 and November 2013 that had a minimum follow-up of 1 year. Within that larger group, we identified 50 patients with DM and used a control group without DM for comparison (n = 55). Clinical outcomes including wound issues, infection rates, complications, and failure rates were then compared. Functional outcomes, including American Orthopaedic Foot & Ankle Society hindfoot score, Short Form-36 (SF-36), Short Musculoskeletal Function Assessment, Foot and Ankle Disability Index, and visual analog scale, were also compared. Median patient follow-up was 2.3 years in the DM group and 3.1 years in the control group (P = .239). Results: The body mass index, age, preoperative American Society of Anesthesiologists (ASA) grading, and smoking history in the DM were significantly higher than in the control group. While 5 patients (10%) in the DM group had secondary operations related to the TAR, no patients had a superficial or deep infection. Eight patients (14.5%) in the control group had secondary operations, including 1 patient who needed a flap. There was no statistical differences in secondary operations (P = .562), revisions (P = .604), or failure rates (P = .345). For both the diabetes and control groups, all functional outcome scores except SF-36 General Health significantly improved at 1 year postoperatively; these improvements were maintained at most recent follow-up. There was no statistically significant difference between the groups regarding functional outcomes except that at 1 year, the magnitude of improvement in SF-36 General Heath was significantly better in the control group. Conclusions: Total ankle arthroplasty appears to be an effective and safe means for providing pain relief and improving function in patients with diabetes and ankle arthritis. While patients with DM were heavier and had worse ASA preoperative grades, they did not have a significantly different complication or infection rate. Level of Evidence: Level III, retrospective comparative study.