Abstract
In the present investigation, a geometrical description of the range of motion (ROM) of lower limb multiple joints including the effects of biarticular muscles was developed. The ROM illustration was also represented mathematically in the matrix formulation indicating separately the ROM due to monoarticular and biarticular muscles. This systematic and quantitative method involves all the conventional clinical ROM measurements and is able to be applied even to patients with severe joint contracture. Photographic analysis was used to measure lower limb joint angles in patients with spastic cerebral palsy (SCP) and normal subjects, then, their ROM was assessed by the geometrical method. The SCP patients showed greater reduction in the ROM of the joints presumably due to the joint soft tissue contracture and the shortening of both monoarticular and biarticular muscles. The symptoms seem to result from their disused joint mobility as well as the intrinsic spasticity. From the results, the necessity and usefulness of the geometrical method were also determined.
