Obesity may impair the early outcome of total knee arthroplasty.

OBJECTIVE

Obesity has been linked to the development of osteoarthritis of the knee and increases the probability to fall into total knee arthroplasty. In this study we compared short-term outcome of total knee arthroplasty (TKA) in non-obese and obese patients.

METHODS

A total of 100 patients underwent TKA between October 2006 and March 2007. They were divided into two groups based on the body mass index: 52 of the patients were obese (BMI = 30 kg/m2) and 48 non-obese (BMI < 30 kg/m2). The short-term out-come was studied using clinical, functional and radiological analysis. The mean of the follow-up period was 3 months.

RESULTS

There were five complications (2 wound infections, phlebitis, nerve injury and massive edema) in obese patients group compared with no complications in non-obese (p = 0.028). The obese patients had also worse postoperative range of motion (110 degrees vs.118 degrees , p = 0.001) than non-obese and the number of technical errors was 17 in obese and 5 in non-obese group, respectively (p = 0.007).

CONCLUSIONS

We suggest that obesity may impair the early outcome of total knee arthroplasty and obese patients should be informed about the increased risk of complications related to TKA. Key words: Total knee arthroplasty; body mass index; obesity; complications; range of motion; mechanical axis.