People with osteoarthritis who wear special mobility shoes can help ease knee pain and slow disease progression, according to research presented at the annual scientific meeting of the American College of Rheumatology, Atlanta.

Osteoarthritis (OA) caises changes in the structures around the joint such as fluid accumulation, bony overgrowth, and loosening and weakness of muscles and tendons, all of which may limit movement and cause pain and swelling.

"Forces on the knee joint during walking have been shown to be related to pain, severity and progression of knee osteoarthritis," said Najia Shakoor, MD, associate professor of medicine at Rush University, Chicago, and lead investigator in the study. "Therefore, researchers currently investigate strategies to reduce these forces or loads on the knee joint in hopes of preventing progression of the disease." Shakoor’s study recently tested these strategies by studying how the use of mobility shoes—flat and flexible shoes, created specifically for this research, that allow natural foot mobility and provide sufficient support for the foot—can affect knee OA.

At the beginning of the study, researchers used a special camera system and a force plate to determine gait in 16 participants (who were all diagnosed with knee OA through X-rays and based on symptoms) while they walked in their own shoes, in mobility shoes, and barefoot. After the initial evaluation, participants were instructed to wear the mobility shoes a minimum of 6 hours per day, six days a week for 6 months. To determine the progression of each participant, researchers performed the same gait analysis that was performed at the beginning of the study at 6, 12, and 24 weeks.

Overall, researchers determined that mobility shoes, in comparison to conventional shoes, led to significantly decreased knee loads in the participants. Additionally, they found that longer-term use of the mobility shoes led to even better outcomes in participants–noting a reduction in knee load that increased from 3.7% at the beginning of the study to 9.4% after 6 weeks, and to 18% at 6 months. Finally, researchers found that after 24 weeks of wearing mobility shoes, participants experienced an adaptation in their gait (with a knee load reduction of 11%) even when wearing conventional shoes–leading researchers to believe that the use of mobility shoes could create beneficial neuromuscular and behavioral changes in how people with OA walk.

"This study showed that specialized footwear was beneficial in reducing knee loads substantially over 6 months," Shakoor said. "It is also the first study to show that chronic use of a mechanical, knee-load reducing intervention could lead to favorable alterations in the way participants walk–even once the intervention is removed. "

[Source: American College of Rheumatology]