As the population ages, knee and hip replacements are likely to become increasingly popular surgical procedures. These operations are generally used to correct joint damage from osteoarthritis. The immediate benefit is obvious: a decrease in pain that often limits patients' mobility. But now researchers at Mount Sinai School of Medicine in New York say that people with new hips and knees also lose significant amounts of weight and decrease their Body Mass Index (BMI).
Their study, recently published in the journal Orthopedics, is considered important because it corrects for the yearly increase in BMI usually experienced by North Americans between the ages of 29 and 73. They looked at 196 Mount Sinai patients who had their knees or hips replaced from 2005 to 2007. About 65 percent were female and 35 percent were male; their mean age was 67.56. Almost 20 percent lost five percent or more of body weight after their surgery.
Patients who were considered obese before surgery because of BMIs over 30 were most likely to experience significant weight loss. Patients were new knees lost more than patients with new hips. The researchers say these results indicate that after the surgery, people were more likely to adopt a healthier lifestyle. Overweight patients often say that pain limits their ability to exercise and makes it harder to lose weight. But after the surgery, with the pain gone, they can become more active.