Long term outcome and survivorship analysis of primary total knee arthroplasty in patients with diabetes mellitus.

Sixty-eight consecutive primary total knee arthroplasties in 51 patients with diabetes mellitus were assessed for long term outcome and risk factors. The mean followup was 8 years. There was a higher complication rate compared with that of a matched control group. Wound complications occurred in 4 knees, deep infection in 1, periprosthetic fractures in 3, and definite aseptic loosening in 5. Urinary tract infections occurred in 4 patients. Radiolucencies of more than 1 mm were observed in 38% of arthroplasties. At last followup, the Hospital for Special Surgery knee score was 77 +/- 12 points, which is worse than the 86 +/- 10 points of the control subjects. Only 74% of the patients had a satisfactory clinical result. Survivorship analysis showed a 91% probability of implant survival at 10 years, which was not significantly different from that of the control subjects. Previous surgery and increased weight were the only risk factors associated with implant failure.