Overweight and obesity: two predictors for worse early outcome in total hip replacement?

OBJECTIVE: Doctors and patients assume that overweight and obesity are negative predictors for good and excellent early outcome after total hip replacement. It was the purpose of this prospective investigation to assess whether overweight or obese patients have worse early postoperative outcome in comparison with normal-weight patients. RESEARCH METHODS AND PROCEDURES: Sixty-seven consecutive patients receiving a total hip replacement were enrolled in the study. Patients were grouped into three samples according to BMI: normal-weight (BMI < 25 kg/m(2), n = 11), overweight (BMI 25 to 29.9 kg/m(2), n = 36), and obese (BMI >or=30 kg/m(2), n = 20). At 10 days and at 3 months after surgery, the patient-centered outcome was analyzed with a self-administered assessment chart, the Western Ontario and McMaster Universities (WOMAC) Osteoarthritis Index. Statistical analysis was performed with a multiple regression model that took into consideration further confounding parameters (age, sex, affected side, anchorage of the implant, duration of surgery, hospital length of stay, and prior pain, stiffness, and function).
RESULTS: No significant influence of individual BMI on subjective outcome according to the WOMAC questionnaire was observed at either 10 days or 3 months after surgery. Hospital length of stay was comparable, and WOMAC scores did not differ significantly preoperatively, at 10 days, or at 3 months postoperatively among patients with different BMI. DISCUSSION: These data showed that the BMI of the patients in our study sample had no significant impact on early outcome or hospital length of stay after total hip replacement. Our data suggest, therefore, that body weight should not be a justification for withholding surgery from overweight or obese patients.