An interview will be administered and if appropriate, potential candidates will be asked a series of questions taken from the pain section of the Western Ontario McMaster Universities Index of Osteoarthritis (WOMAC). Patients with a WOMAC pain score ≥ 3 will then be asked to have a series of X-rays taken of their knees. Those individuals who display radiographic evidence of knee OA will be asked to participate in the study until the twenty five positions are filled. At their next pre-bariatric surgery visit, the study participants will have a basic knee exam performed by Kevin P. Black, M.D. in order to evaluate the structural integrity and alignment of the knee joint. The information gathered from the exam will serve as a baseline measure of knee function for the study. Prior to undergoing surgery, each of the 25 patients will be asked to complete a full version of the WOMAC survey and a separate, related survey the Knee and Osteoarthritis Outcome Score (KOOS). These surveys will be re-administered at 6, 12, and 24 months post-surgery in order to assess any changes in knee pain and function.