Infection is a relatively rare but potentially serious complication after anterior cruciate ligament (ACL) reconstruction1-4. Because of the low prevalence of infection after ACL reconstruction, a study of such infections requires a large cohort in order to control for heterogeneous factors and to facilitate meaningful analysis of associated risk factors. Recent studies on infection after ACL reconstruction have demonstrated that graft choice may be a risk factor1,4. Smoking has been shown to be a risk factor for infection after orthopaedic surgery5,6, and obesity increases the risk of infection after spinal surgery7,8 and arthroplasty9,10. Diabetes is well known to be associated with an elevated risk of surgical site infections in a variety of surgical specialties11-13, including orthopaedics.