Can single limb support objectively assess the functional severity of knee osteoarthritis?

Elbaz et al., The Knee, 2011
This study showed that objective measures of single-limb support (SLS); taken from 125 patients with bilateral knee osteoarthritis, increase consistently with the subjective improvements reported by the patients in universally recognised pain and joint function assessments (WOMAC and SF-36 questionnaires). Furthermore, the study’s use of a quintiles classification for SLS suggests that this evaluation can provide a useful scale for generally assessing the symptomatic stage of knee osteoarthritis.

Patients suffering from knee osteoarthritis experience pain, stiffness and decreased range of motion. These limitations can be measured subjectively by pain, function and quality of life questionnaires and objectively using computerised gait analysis. SLS represents a phase in the gait cycle when the body’s weight is entirely supported by one limb, while the second limb swings forward to take the next step.
125 patients, 79 women and 46 men with a mean age of 66 participated in the study. They underwent a physical and radiographic evaluation, and completed the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and the SF-36 health surveys measuring pain, function and quality of life.

The patients then walked barefoot at a self-selected speed on a computerised mat and the length of time they spent on one leg while walking was recorded. The patients were then divided into five groups based on the length of their single-limb support phase. The differences in the patients’ WOMAC and SF-36 scores were then examined in relation to the group they were in. Patients reported more pain, reduced function and a lower quality of life when they were in groups that reflected less time spent on a single limb.
The study’s outcomes support the therapeutic benefits of AposTherapy which has been clinically proven to improve gait patterns in patients with knee osteoarthritis. The study showed that improvements in single limb support directly correlate with pain relief, improved function and quality of life. Furthermore, the quintiles classification of SLS applied by the study can provide a valuable scale contributing to the better treatment and understanding of knee osteoarthritis.

Elbaz A, Mor A, Segal O, Agar G, Halperin N, Haim A, Debbi E, Segal G, Debi R. Can single limb support objectively assess the functional severity of knee osteoarthritis? Knee 2011 Epub ahead of print.

Elbaz et al., The Knee, 2011