Changes in knee moments with contralateral versus ipsilateral cane usage in females with knee osteoarthritis.

BACKGROUND

Conservative treatment for osteoarthritis often involves educating the patient in methods of decreasing the load transmitted through the diseased joint. The use of a cane is one such method and the correct placement of the cane with respect to an abnormal knee joint is crucial. The purpose of this study was to compare effects on knee moments of force of contralateral versus ipsilateral cane usage in female subjects with osteoarthritic knees.

METHODS

A convenience sample of 14 subjects volunteered for this study. Subjects walked over force platforms while ground reaction force and three-dimensional kinematic data were captured using a Vicon 370 System. The subjects were tested walking: (a) unaided, (b) with ipsilateral cane, and (c) with contralateral cane. Inverse dynamics were employed to calculate temporal-spatial, kinematic and kinetic variables. Dependent variables included hip and knee frontal plane and sagittal plane moments of force, walking speed, cadence and stride length. Repeated measures ANOVA assessed differences among walking conditions.

FINDINGS

Subjects walked significantly faster in the unaided gait condition owing to a higher cadence. Ipsilateral cane use resulted in significantly larger hip (versus contralateral P=0.018; versus unaided P=0.036) and knee (versus contralateral P=0.043; versus unaided P=0.030) frontal plane peak moments during gait. Contralateral cane placement was associated with the smallest peak knee abductor (P=<0.001) and flexor (P=<0.001) moments. Knee deformity (varus or valgus) did not have any significant effect on any variable possibly due to small sample size.

INTERPRETATION

The results suggest that as is the case for the hip contralateral cane placement is the most efficacious for persons with knee osteoarthritis. In fact, no cane use may be preferable to ipsilateral cane usage as the latter resulted in the highest knee moments of force, a situation which may exacerbate pain and deformity.