Suffering from osteoarthritis of the knee? The kind of shoe you wear may be the reason, according to a new study.
The study, by researchers at Rush Medical College, shows that slippers, or flip-flops, and flat walking shoes put the least pressure on the knee, while shoes that restrict foot movement increase the risk of knee osteoarthritis (OA).
Findings of the study were presented at the annual scientific meeting of the American College of Rheumatology.<b1>
Knee OA is caused by cartilage breakdown in the knee joint. Obesity, age, injury or stress and family history can increase the risk of knee OA, reports Sciencedaily.com.
There is abundant evidence that knee OA patients with abnormally high loading knees - that is, high stress on the knee joint -- are at increased risk.
Researchers studied the effects of various types of footwear on 13 women and three men with knee OA.
Each participant underwent "gait analysis" while barefoot and while wearing a clog, a stability shoe (designed to limit foot movement), a flat flexible walking shoe and flip-flops.
The researchers found that clogs and stability shoes were associated with significantly higher loading of the knees, while the walking shoes and flip-flops resulted in lower knee loads similar to those occurring when walking barefoot.
"These results highlight the importance of re-evaluating the design of modern-day shoes in terms of their effects on knee loads and knee OA," said Najia Shakoor, an investigator in the study.
"Knee loads play an important role in the progression of knee osteoarthritis," she explained.
"Results from this study suggest that shoes can significantly affect the amount of load on osteoarthritic knees -- with flat, flexible shoes providing the greatest degree of benefit in terms of knee loading."