Study finds knee replacement surgery may lead to weight gain

(Press-News.org) RICHMOND, Va. (Jan. 14, 2013) – Patients who undergo knee replacement surgery may be at risk of gaining more weight than their peers who have not had the surgery, according to a five-year study led by a Virginia Commonwealth University professor.

Daniel Riddle, Ph.D., professor in the VCU Department of Physical Therapy in the School of Allied Health Professions, and his research team reviewed the medical records of nearly 1,000 knee-replacement surgery patients from the Mayo Clinic Health System and found that 30 percent of them gained 5 percent or more of their body weight in five years following surgery.

In a comparison group of people who had not had surgery, only 20 percent gained equivalent amounts of weight during the same period.

"Part of the explanation is that people may have spent years adapting to their circumstances by avoiding activities that could cause knee pain," Riddle said. "We need to encourage patients to take advantage of their ability to function better and offer strategies for weight loss or weight management."

The study also shows that preoperative weight loss is a risk factor that frequently leads to weight gain following the procedure.

Overweight and obese patients preparing for surgery are frequently encouraged to lose weight prior to surgery to aid in enhancing early recovery and reduce the risk of complications.

"The subsequent weight gain potentially puts patients at risk of developing chronic health conditions, such as cardiovascular disease or diabetes," said Riddle.

### Riddle, the Otto D. Payton Professor in the Department of Physical Therapy, collaborated with Jasvinder A. Singh, M.D., Birmingham Veterans Affairs Medical Center; William S. Harmsen, Mayo Clinic; Cathy D. Schleck, Mayo Clinic; and David G. Lewallen, M.D., Mayo Clinic College of Medicine.

The study is published online in the journal Arthritis Care & Research.

About VCU and the VCU Medical Center Virginia Commonwealth University is a major, urban public research university with national and international rankings in sponsored research. Located in downtown Richmond, VCU enrolls more than 31,000 students in 222 degree and certificate programs in the arts, sciences and humanities. Sixty-six of the programs are unique in Virginia, many of them crossing the disciplines of VCU's 13 schools and one college. MCV Hospitals and the health sciences schools of Virginia Commonwealth University compose the VCU Medical Center, one of the nation's leading academic medical centers. For more, see www.vcu.edu.