Retrograde ankle arthrodesis using an intramedullary nail: a comparison of patients with and without diabetes mellitus.

Tibiotalocalcaneal arthrodesis (TTCA) has been used for the salvage of severe deformity involving the ankle and hindfoot. The purpose of this study was to evaluate the results of retrograde intramedullary nailing (IMN) for severe ankle/hindfoot pathology in a group of patients with diabetic neuropathy and compare them with a cohort of nondiabetic patients. Our working hypothesis was that patients with diabetes mellitus (DM) and neuropathy would experience inferior outcomes and more postoperative complications than patients who did not have DM. Forty consecutive patients (17 with DM and 23 without DM) who had a minimum follow-up of 1 year were retrospectively reviewed. The mean follow-up was 33 months and the mean AOFAS Ankle Hindfoot Score significantly improved form 19 to 55. Patients with DM improved on average from 24 to 55 and patients without DM improved from 16 to 55. Although a postoperative complication was experienced in 59% of patients with DM compared with 44% of patients without DM, this difference did not reach statistical significance with the numbers available. More patients with DM used a brace at final follow-up than patients without DM. Those patients who had a history of preoperative skin ulceration had higher rates of infection than those patients who did not have skin ulcers. We did not find any significant postoperative differences in AOFAS Ankle Hindfoot Scores between those patients with DM versus patients without DM. On average, patients with DM demonstrated an improvement of 129% and patients without diabetes improved by 243%. With the numbers available, we were not able to confirm our hypothesis that patients with DM experienced significantly lower clinical outcomes than patients without DM. A study of 100 patients in each group would be necessary to achieve adequate power to conclusively state that DM had no impact on the final outcome.