Obesity Is Big Complication for TKA
Biloine W. Young • Fri, November 7th, 2014
Orthopedic surgeon William M. Mihalko, M.D., Ph.D., of Campbell Clinic Orthopaedics in Memphis, Tennessee, lays it on the line. “Obesity, ” he says, can have a significant impact on a patient’s outcome from elective orthopaedic surgery.” He co-authored “Obesity, Orthopaedics and Outcomes, ” a study published in the Journal of the American Academy of Orthopaedic Surgeons in which he noted that even though patients with obesity face higher surgical complication rates, orthopedic procedures can help minimize pain and improve bone and joint function.
That is the good news. The bad news is that osteoarthritis is associated with obesity. The need for a total knee arthroplasty (TKA) is estimated to be at least 8.5 times higher among patients with a body mass index (BMI) greater than or equal to 30, compared with patients who have a BMI within the normal range of 18.5 to 24.9. Every pound of body weight places four to six pounds of pressure on each knee joint.
Mihalko reports that obesity is a strong independent risk factor for pain. The disease nearly doubles the risk of chronic pain among the elderly, he writes, and adolescents with obesity are more likely to report musculoskeletal pain, including chronic regional pain, than their normal-weight peers.
In addition to the wear and tear on joints, excess weight also affects injury status, Mihalko maintains. The odds of sustaining musculoskeletal injuries is 15% higher for persons who are overweight and 48% higher for people who are obese, compared to persons of normal weight.
The study authors recommend that patients with morbid obesity, a BMI of 40 or higher, be advised to lose weight before receiving a TKA. Doctors should offer resources for weight loss before surgery; and counsel patients about the possible complications and inferior results that may occur if they do not lose weight.
An orthopedic surgeon in Minnesota, known to the writer, had a patient with a BMI of 50 who needed a new knee joint. He refused to perform the surgery until the patient lost some weight. She was irate with her surgeon but, the doctor reports, she is presently on a weight-loss program.