Diabetes is known to be associated with infectious complications after orthopedic procedures, and a recent study indicates that obesity and diabetes are independent risk factors for postoperative surgical-site infections (SSIs).
The study, performed in a Finnish hospital specializing in joint replacement, explored the effects of obesity and diabetes on infection rates after primary hip and knee replacement procedures. This population-based series included 7181 hip and knee replacements performed for osteoarthritis between 2002 and 2008. Plasma glucose was measured repeatedly before and during the hospital stay, and hyperglycemia was defined as glucose ≥6.9 mmol/L (124 mg/dL). Patients were evaluated prospectively for the occurrence of periprosthetic joint infection during the year after surgery.
Joint infections were diagnosed after 52 procedures (0.72%). Morbid obesity (≥40 kg/m2 ) was associated with significantly more infections than was normal body weight (<25 kg/m2 ), with infection rates of 4.66% versus 0.37%, respectively. Morbid obesity remained significant in multivariate analysis (OR 6.4; 95% CI, 1.7-24.6), although intermediate levels of obesity (25-29, 30-34, and 35-59 kg/m2 ) were not significant. Hip replacements in morbidly obese patients were associated with a 30-fold elevation in infection risk, and knee replacements with an 8-fold increase.
Jämsen E, Nevalainen P, Eskelinen A, Huotari K, Kalliovalkama J, Moilanen T. Obesity, diabetes, and preoperative hyperglycemia as predictors of periprosthetic joint infection: a single-center analysis of 7181 primary hip and knee replacements for osteoarthritis. J Bone Joint Surg Am. 2012;94(14):e1011-e1019.