Cane use may reduce risk of knee osteoarthritis progression

All participants were tested first in bare feet, followed immediately by testing in their own shoes—a comfortable pair typically used for walking. 20 of the participants were further tested wearing their own shoes and using a cane in the opposite hand to the study knee, after a brief instruction in ideal cane use by a physiotherapist. Data from 5 successful trials were collected for each test. A mean score was used to calculate changes in gait parameters and determine the peak knee adduction moment.

Overall, the peak knee adduction moment when walking in shoes was significantly higher—7.4 percent—than when walking barefoot. The effect of footwear, however, varied considerably among individuals. While most demonstrated an increased knee adduction moment while wearing shoes, 6 of the 40 subjects actually demonstrated a beneficial decrease. The use of a cane resulted in a striking 10 percent average decrease in the knee adduction moment. What’s more, a quarter of the participants demonstrated a reduction of more than 20 percent. While individuals tended to walk more slowly with the cane than unaided, they exhibited greater stride length and improved pelvis control, alleviating the destructive load on the affected knee.

Though canes are widely recommended to knee OA patients, this study validates their therapeutic value, at least in the short-term. “Further studies are required to establish whether knee loading remains lower with ongoing use of a cane,” notes Dr. Hinman, “and whether the reductions in loading translate to a reduced risk of disease progression.” Additional studies should also focus on men with knee OA, since 90 percent of the participants in this cane trial were women, and examine changes in knee pain, an issue which the team did not address.

On the other critical matter of footwear, Dr. Hinman admits lack of a clear explanation for why wearing shoes increased the peak knee adduction moment. Heel height, sole thickness, and arch supports may all play a contributing role. “Because it is potentially dangerous as well as impractical to advise patients with knee OA to walk about in bare feet, further research is needed to determine which types of shoes least increase the knee adduction moment or, ideally, reduce it,” Dr. Hinman observes. “The shoe type optimal for knee OA with regard to its effects on symptoms and disease progression must be determined.”

Article: “Reducing Joint Loading in Medial Knee Osteoarthritis: Shoes and Canes,” Georgina Kemp, Kay M. Crossley, Tim V. Wrigley, Ben R. Metcalf, and Rana S. Hinman, Arthritis & Rheumatism (Arthritis Care & Research) , May 15, 2008; 59:5, pp. 609-614.