Studies link weight loss to decreased pain, successful joint replacements

Many people associate weight loss with a better aesthetic image of themselves, and while the health benefits are obviously known as well, they most often come as a secondary benefit in a diet and exercise regimen. For patients with serious or chronic health conditions, however, recent studies that reviewed orthopedic documentation in relation to overall body mass indices suggested that weight loss benefits several aspects of the rehabilitation and pain management processes post-surgery.

While one study focused on the comparative effects of weight loss and total knee replacement in relation to overall pain reduction and another tracked the added benefits of decreased mass and stress on artificial joint surgeries, both found that losing weight has positive health effects for the condition of patients.

Reducing joint pain through weight loss
For some patients, osteoarthritis is virtually unavoidable as they age. Congenital effects may combine with poor diets and lack of activity to result in knee pain that warrants a total joint replacement.

However, according to a study presented at the annual conference of the American Academy of Orthopaedic Surgeons in New Orleans on March 14, significant weight loss in obese patients that removes excess stress from the knee may be just as effective in managing pain from osteoarthritis as replacing the joint.

The study looked at 60 obese patients who complained of knee pain, 40 of whom underwent knee replacement surgery and 20 of whom had weight-loss surgery. A year after their respective procedures, both patient groups reported that their pain levels had dropped to near-identical levels. 

The weight-loss group also reported greater mobility and knee function six months after their procedure, while it took a full year for the replacement surgery group to match those levels.

Improving joint replacement outcomes through weight loss
In some cases, the pain from arthritis is too severe to be managed by weight loss alone and total joint replacement is the only option.

However, a separate study conducted by Geoffrey Westrich, M.D., senior investigator and director of research of Adult Reconstruction and Joint Replacement at the Hospital for Special Surgery in New York, found that significant weight loss can be instrumental in improving the overall success rate and pain levels of patients who must undergo knee or hip replacements.

Westrich's study followed 3,036 knee replacement patients and 3,893 hip replacement patients and tracked their relative BMIs through orthopedic EMR systems before and after the procedures. The study concluded that while maintaining or losing weight after surgery returned patients to their original comfort and mobility levels, those who gained weight saw increased pain and decreased joint functionality.

"Our findings represent the first report to present evidence that weight loss is associated with improved clinical outcomes, while weight gain is associated with inferior outcomes, although these results are really not surprising," Westrich said in a statement.

Associating weight loss and joint replacement surgery success could have larger implications for improving quality of care, Westrich argued. If physicians can more specifically articulate the need for patients to manage fluctuations in weight surrounding orthopedic procedures, those patients may see increased quality of life as a result.