Advanced Orthopedics for Joint Replacement

According to a recent article in Science Daily last February 2010, a study in Delaware University found out that a person who underwent knee surgery would most probably gain weight.

According to the research headed by Joseph Zeni and Lynn Snyder-Mackler from the Department of Physical Therapy in UD's College of Health Sciences found that patients typically drop weight in the first few weeks after total knee arthroplasty (TKA), but then the number on the scale starts creeping upward, with an average weight gain of 14 pounds in two years.

A total of 137 individuals participated in the study. There were 106 individuals with end-stage osteoarthritis who had knee replacement surgery, and an age-matched, healthy control group of 31 subjects who did not have surgery. The researchers measured all the participant’s height, weight, quadriceps strength, and self-perceived functional ability during an initial visit to UD's Physical Therapy Clinic, and at a follow-up visit two years later.

They saw that sixty-six percent of those who had knee replacement gained an average of 14 pounds in a span of two years. Also they found out that the weaker the surgery patient was the heavier they become. "These findings are making us re-think the component after total knee surgery and of patients not being in a routine of moving around," says Snyder-Mackler, Alumni Distinguished Professor of Physical Therapy at UD.

Dr. Mackler also said that it is critical that people not wait too long to have a knee replaced because their functional level going into surgery typically dictates their functional level after surgery.

Gaining weight after one knee replacement is worrisome because it could jeopardize the patient's other knee. Between 35-50 percent will have surgery on the other side within 10 years, Snyder-Mackler says.

The researchers note that weight gain after a knee replacement needs to be treated as a separate concern and integrated into post-operative care through a combination of approaches, including nutritional counseling to help patients with portion control, and more emphasis on retraining patients with new knees to walk normally.

"For physical therapists and surgeons, the common thinking is that after a patient's knee has been replaced, that patient will be more active," says Snyder-Mackler. "But the practices and habits these patients developed to get around in the years prior to surgery are hard to break, and often they don't take advantage of the functional gain once they get a new knee," she notes.

"We need to re-train patients with new knees to walk more normally and more systematically. And we need to encourage more community participation," Snyder-Mackler adds. "If you're not getting out of the house, you won't gain the benefit. We need people with new knees to get out there -- with the help of their family, their friends, and the community at large."

An article from Science Daily