Relations between Long-term Glycemic Control and Postoperative Wound and Infectious Complications after Total Knee Arthroplasty in Type 2 Diabetics

BACKGROUND The authors examined whether poor preoperative glucose control, as indicated by the hemoglobin A1c (HbA1c) level of more than 8%, is associated with postoperative wound and infectious complications in diabetic patients that have undergone total knee arthroplasty (TKA). METHODS One hundred and sixty-seven TKAs performed in 115 patients with type 2 diabetes mellitus, from January 2001 through March 2007, were retrospectively reviewed. Logistic regression was used to identify the variables that had a significant effect on the risk of wound complications or early deep infection. The variables considered were age, gender, body mass index, comorbidities, operation time, antibiotic-impregnated cement use, amount of blood transfusion, close suction drain use, duration of diabetes, method of diabetes treatment, diabetes complications, and preoperative HbA1c level. RESULTS The overall incidence of wound complications was 6.6% (n = 11) and there were seven cases (4.2%) of early postoperative deep infection. Logistic regression revealed that the independent risk factors of wound complications were preoperative HbA1C ≥ 8% (odds ratio [OR], 6.07; 95% confidence interval [CI], 1.12 to 33.0) and operation time (OR, 1.01; 95% CI, 1.00 to 1.03). No variable examined was found to be significantly associated with the risk of early postoperative deep infection. CONCLUSIONS Poorly controlled hyperglycemia before surgery may increase the incidence of wound complications among diabetic patients after TKA.