Rx for Knee Osteoarthritis: Walking Shoes and a Cane
Cane use can help reduce the risk of knee osteoarthritis progression, according to researchers. The knee is the most common joint affected by osteoarthritis. Using a cane takes stress off of the knee. By reducing the risk of knee osteoarthritis progression, disability may also be prevented.
Osteoarthritis most commonly affects a part of the knee known as the inner aspect of the tibiofemoral joint. A source of stress for this knee component is the knee adduction moment (an indication of weight placement while walking). A 20% increase in peak knee adduction moment is associated with at least a 6-fold increase in the risk of knee progression over 6 years.
Doctors typically offer two easy solutions for reducing knee load, joint pain, and joint damage in knee osteoarthritis patients:
- footwear, such as good walking shoes
- cane use
Gait Analysis With Walking Shoes and Cane
Researchers from the University of Melbourne used 3-dimensional gait analysis to study the immediate effects of walking shoes and a walking cane on peak knee adduction moment in knee osteoarthritis patients. Study results supported using a cane on a regular basis to reduce the load across the knee.
There were 40 study participants - 24 women and 16 men. All of the study participants had established knee osteoarthritis with medial tibiofemoral osteophytes, persistent pain, loss of physical function. None of the participants, whose mean age was 65 years old, had joint replacement surgery.
The 3-dimensional gait analysis employed a Vicon 6-camera motion analysis system. Two force plates were embedded in the walkway of the test area to detect ground impact. Reflective markers placed on the pelvis, thigh, knee, and foot helped assess limb movement.
All of the study participants were tested in bare feet, and wearing their own walking shoes. Twenty of the participants were also tested using a cane (in the hand opposite the affected knee) while wearing their own walking shoes. As researchers collected data, they determined the peak knee adduction moment.
Gait Analysis Results
Generally the peak knee adduction moment with walking shoes was 7.4% higher than when walking barefoot. The effect of footwear varied among the study participants -- perhaps depending on the style of footwear. While most participants had an increased knee adduction moment with shoes, 6 of the 40 participants actually had a decrease in knee adduction moment, which is beneficial.
There was a 10% average decrease -- a significant decrease -- in knee adduction moment with cane use. One-fourth of the participants achieved a 20% reduction in knee adduction moment.
With the cane, participants tended to walk more slowly than when walking without the cane. But with the cane, they had greater stride length (took bigger steps) and improved pelvis control -- both of which lessen the destructive load on the affected knee.
This particular study showed the benefit of short-term cane use. Further studies are needed to establish long-term benefit of cane use. Shoe styles that could benefit knee osteoarthritis should also be studied.
Reducing joint loading in medial knee osteoarthritis: Shoes and canes. Kemp G et al. Arthritis Care & Research. May 15, 2008.