Postoperative wound infection rates after posterior instrumented spinal surgery in diabetic patients

Background: Diabetes mellitus is thought to be a risk factor for surgical site infection. There have been no reports about the infection rate in diabetic patients who have undergone posterior spinal instrumented fusion. We present a retrospective analysis of infection rates after posterior spinal instrumented fusion in diabetic and non-diabetic patients. Methods: Of 337 patients who underwent posterior spinal instrumented fusion between 1995 and 1997, 39 were diabetic. Plasma glucose concentration, body mass index, type of instrument, operation time, blood loss, hospital stay and complications were recorded. The pathogenic organism and treatments for infection were also described. Results: The rate of wound infection in diabetic patients was 10.3% compared with 0.7% in non-diabetic patients (p = 0.003). Body mass index and preoperative blood sugar were also significantly different between the two groups (p = 0.02, p < 0.001). Conclusions: Patients with a diabetic history or preoperative hyperglycemia had a higher infection rate after posterior spinal instrumented fusion when compared with non-diabetic patients.