Perhaps women can bear pain better than men, or a woman’s world increasingly revolves around the home as they age, or it could be that women are just trying to follow doctor’s orders.

Research at the University of Delaware indicates that women wait longer to pursue knee-replacement surgery than men do.

By postponing surgery until they can no longer stand the pain, these women may also risk putting their mobility, and quality of life, on hold indefinitely, according to Lynn Snyder-Mackler, Distinguished Alumni Professor in UD’s Department of Physical Therapy and a certified sports physical therapist and athletic trainer.

“Doctors typically tell patients to wait to have knee replacements until they just can’t stand the pain any longer,” Snyder-Mackler said. “Our research shows that’s bad advice—and worse for women than it is for men—because your level of function going into surgery generally dictates your level of function after surgery,” she noted.

At UD’s Physical Therapy Clinic in McKinly Laboratory, 229 candidates for total knee replacements, including 95 men and 126 women with osteoarthritis, were evaluated and compared to 44 healthy men and women who matched them in gender, age and body-mass index. Each subject took part in a series of standard physical tests such as stair climbing and the distance covered in a 6-minute walk.

While the men generally were stronger and had more knee function than the women, the test results showed a much greater degree of physical disability in the female knee-replacement candidates compared to the males in the group.

“The women afflicted with osteoarthritis were at a much more advanced stage than the men with the disease,” Snyder-Mackler said. “The women all had painful end-stage osteoarthritis, where the cushion of cartilage padding the knee bones has completely deteriorated and you basically have bone hitting against bone.”

“Osteoarthritis of the knee is the most common cause of disability among Americans. It’s a disease of age that affects more women than men on a 60-40 basis,” Snyder-Mackler said. “Physicians generally have advised patients to wait as long as they can before pursuing knee replacements, with the thinking that it is a once-in-a-lifetime surgery that should last an average of 20 years. However, delaying surgery can limit the quality of life of patients because how they function before surgery indicates their performance afterward.”

Women need to become more educated about the risks and benefits of knee-replacement surgery, Snyder-Mackler said, and heed the warning signs of serious problems.

“When you feel profound buckling and weakness in your knee when climbing stairs, that is a major problem. You compensate—eventually, you may come downstairs only once a day,” Snyder-Mackler said. “As a result, you become sedentary and that’s not good for your health. Earlier intervention can help preserve your mobility and quality of life.”