Elevated Preoperative Hemoglobin A1c Associated with Increased Wound Complications in Diabetic Patients Undergoing Primary, Open Carpal Tunnel Release

Background: An increased rate of complications has been demonstrated with increasing hemoglobin A1c value for a variety of orthopedic procedures, including arthroplasty and spine surgery. The authors investigated the effects of elevated hemoglobin A1c value on postoperative complications at the time of carpal tunnel release. Methods: This retrospective, cohort study evaluated all diabetic patients with a preoperative hemoglobin A1c value within 90 days of primary, open carpal tunnel release at a single academic institution within the past 10 years. Binary hemoglobin A1c thresholds were tested for association with outcomes of superficial or deep infection, delayed wound healing, and persistent symptoms using chi-square analysis. Multivariable models with adjustment for baseline and operative factors were then constructed. Odds ratios and 95 percent confidence intervals were displayed. Results: Hemoglobin A1c value greater than or equal to 7.8 percent was most strongly associated with an increased risk of all-cause wound healing complications (p = 0.049) at an odds ratio of 4.2 (95 percent CI, 1.0 to 17.7) in adjusted analyses. Six patients (4 percent) experienced delayed wound healing and five patients (4 percent) developed a superficial infection. Six patients (4 percent) reported persistent carpal tunnel syndrome symptoms. Conclusions: Diabetic patients undergoing open, primary carpal tunnel release with a hemoglobin A1c value of 7.8 percent or higher had a higher rate of postoperative wound complications compared to diabetic patients with improved preoperative glucose control. Diabetics with poor glycemic control should be counseled that their risk of postoperative complication is higher. Further work is needed to determine whether delaying surgery to optimize glucose control could result in a reduction of wound healing complications. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, II.