Orthopedic surgeons, rheumatologists and physicians specializing in rehabilitation medicine know that the knee joint has to support the force of three to six times one’s weight. The impact of extra weight is also multiplied on other joints, including those of the back, hips and ankles. The results of this increased wear and tear are impressive; for example, men who are just 40 pounds over their ideal body weight have a five-fold increase in osteoarthritis (1). This close link between obesity and osteoarthritis is well documented (2). Of course, the incidence of severe osteoarthritis in people that are one hundred or more pounds overweight is exponentially higher, and the age of onset is much earlier. As always in medicine, unless patients and their doctors attack the root cause of their disease, in this case arthritis, medications and other therapy will only temporarily alleviate the pain and allow for permanent injury to the bone and cartilage.
For patients who do not yet require surgery to replace damaged joints, substantial weight loss has been shown to alleviate the debilitating symptoms of osteoarthritis. Schauer, et al, documented that seventy percent of patients that were taking medications for joint pain had no pain and were off all arthritis medications after weight loss surgery (3). Another published study documented that 58 percent of patients undergoing weight loss surgery complained of chronic low back pain, but this number decreased to only 20 percent after surgery (4).
Unfortunately, not everyone will have resolution of his or her knee pain after weight loss since joint cartilage lost after years of obesity will never regenerate. This damage may result in the need for surgery to repair or replace the damaged joint. Of course, recovery from joint replacement is more difficult in obese patients and many orthopedic surgeons will not perform joint replacement surgery in severely obese patients because of the significantly higher risk of complications. A patient who is unable to undergo joint replacement due to excess weight is a prime example of a person who needs surgical weight loss.
To evaluate the impact of surgical weight loss on patients requiring joint replacement therapy, the Mayo Clinic followed 20 patients who had hip and knee replacements after weight loss from gastric bypass. This recent study found a significant improvement in physical rehabilitation after joint replacement in patients who had previous weight loss due to gastric bypass. In fact, not only did the recovery from joint replacement improve, the re-operation rate due to complications after surgery was dramatically lower (5).
Everyone is aware that osteoarthritis will often improve with good weight control. For those people who are severely obese and are suffering from chronic joint pain, surgery for permanent weight control may be the best option to help your physician or surgeon improve your treatment results.
1- Annals of Rheumatic Disease; Felson, 1996, 2- Amer. Jour. of Public Health; Sahyoun, 1999, 3- Schauer 20004, 4- Melissas, 2004, 5- Parvizi, 2000