A new study is recommending exercise to patients following a knee replacement surgery as it boosts the function of the new knee and makes it almost as good as that of a healthy adult.
The researchers revealed that exercise is critical to begin three to four weeks after surgery to treat severe knee osteoarthritis.
The joint disease leaves its sufferers with persistent pain and limited function, resulting in an overall diminished quality of life.
"It sounds logical that exercises to strengthen your knee should be a component of your post-operative physical therapy after a total knee replacement, but it's not the convention at all," said Lynn Snyder-Mackler, Alumni Distinguished Professor of Physical Therapy at the University of Delaware.
"There are all of these old wives' tales that strength training is a detriment to the patient and that the new knee should be treated delicately.
"Our study demonstrates that intensive strength exercise as outpatient therapy is critical to begin three to four weeks after surgery," Snyder-Mackler added.
While knee replacement alleviates the pain of osteoarthritis and improves function, patients exhibit impaired quadriceps strength and function for such activities as walking and climbing stairs, and the levels remain below those of healthy people of the same age.
During the study, the researchers conducted a randomized controlled trial at the University of Delaware's Physical Therapy Clinic conducted between 2000 and 2005 on 200 patients, who had undergone knee replacements.
They were given six weeks of progressive strength training two or three times a week starting four weeks after surgery. Half of the group also received neuromuscular electrical stimulation (NMES).
Their function was compared to that of 41 patients who received conventional rehabilitation and home physical therapy. Quadriceps strength, knee range of motion, and gait were measured in such tests as timed up and go, stair climbing and a six-minute walk.
The findings revealed that the group in the progressive strength-training program had significant improvement in quadriceps strength and functional performance.
They also demonstrated substantially greater quadriceps strength and functional performance after 12 months than the group that underwent conventional rehabilitation.
The study is published in Arthritis Care and Research.