Effect of Obesity on Knee Osteoarthritis Symptoms and Surgical Outcomes


Weight loss can be a beneficial and conservative approach to treating patients who are overweight or obese and have knee OA. Weight loss can improve knee pain and overall function and quality of life. It is important for clinicians to address weight loss at all encounters with their patients and help set realistic goals. Discussion about patient goals and perceived barriers to weight loss can set the stage, allowing providers to offer patients resources they need to meet their goals. Most studies show that at least a 10% weight reduction is needed to improve knee pain in OA.9,10,21 If a 10% loss is achieved, encouraging patients to continue their weight-loss journey can help further reduce the workload on their knees.

In patients who undergo surgery, obesity is associated with an increased risk for postoperative infection as well as failure of the prosthesis requiring revision surgery.14,15 Thus, for patients undergoing TKR, clinicians may require weight loss before surgery, particularly if patients are morbidly obese. Although it can be challenging for providers and patients to discuss weight loss, it is in the best interest of patients and will allow them to optimize surgical outcomes. Patients who receive weight-loss counseling are 4 times more likely to achieve success after surgery compared with those who do not receive counseling.22

Weight-loss methods should be determined based on what is best for the patient and what is most feasible in a given timeframe. Primary care providers can help guide patient education about weight loss and treatment options for patients with knee OA considering TKR surgery.   

Natalie Reed, PA-C, is a recent graduate of the Physician Assistant Program at Augusta University in Augusta, Georgia and is currently working in orthopedics in Atlanta. Kelly S. Reed, PharmD, MPA, PA-C, is an assistant professor in the Physician Assistant Program at Augusta University.


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This article originally appeared on Clinical Advisor