Some orthopedists insist that patients with diabetes have tight glycemic control before they undergo total hip or knee replacement, presumably to prevent postoperative infection. To examine the interplay between diabetes and obesity as risk factors for periprosthetic joint infection, Finnish researchers analyzed a single-center database of 7181 primary hip or knee replacement operations. Both deep incisional infections and joint (or joint space) infections that occurred during the first postoperative year were counted.
The overall incidence of infection was 0.7% (52 cases). After multivariate analysis with adjustment for diabetes, body-mass index (BMI), and several other variables, periprosthetic infection was associated significantly with both severe obesity (odds ratio, 6.4) and diabetes (OR, 2.3). The incidence of infection was zero in diabetic patients with BMIs <25 kg/m2 and was between 1% and 2% in diabetic patients with BMIs between 25 and 40. In patients with both diabetes and BMI 40, the incidence of infection was much higher — 10%.
Comment: In this study, severe obesity was associated more strongly with periprosthetic infection than was diabetes; when both factors were present, risk was substantially higher. The data presented in this study were insufficient to determine whether poor glycemic control among diabetic patients was an additional risk factor for infection. Moreover, controlled trials have not been performed to determine whether tightening glycemic control before or after orthopedic surgery improves postoperative outcomes.
Source: Journal Watch General Medicine