Do patients with knee pain from osteoarthritis (OA) increase the weight and load through the knee after taking pain relievers? This is the first study to try and find an answer to the question. Researchers at the University of Chicago say pain relief increases the load while walking, but not during stair climbing. They think other factors may be involved in stair climbing.

Many patients with OA end up with increased wear and tear on the inside edge of the knee. Pain causes them to limp or shift the weight to the other leg. Their walking speed slows down, and their rhythm becomes uneven.

In this study, authors compared two groups: adults with OA, and adults without OA. The study was done in a motion analysis lab. Each group walked on a walkway that can measure force from the ground up through the knee. Speed and stride length were also measured. Three trials of walking and stair climbing were done.

Then the OA group got a knee injection for pain. All patients reported pain relief. After 15 minutes, three more trials were done. The researchers found no change in forces through the knee during stair climbing. Walking did change. It was measured as equal to the group without OA.

The authors conclude that pain relief from knee injections tend to normalize walking in patients with OA. Other factors such as overall health, swelling, and muscle weakness may be why load didn't change with stair climbing.

Reference:

M. Wade Shrader, MD, et al. Effects of Knee Pain Relief in Osteoarthritis on Gait and Stair-Stepping. In Clinical Orthopaedics and Related Research. April 2004. Vol. 421. Pp. 188-193.'