Gait in rheumatoid arthritis: an electrogoniometric investigation.

For the purpose of detecting early aberrations of gait in rheumatoid arthritis 17 women suffering from that disease were examined. They were all under 50 years of age and had an essentially normal range of motility in the hips, knees and ankles. Eleven healthy women walking at voluntary speed and 6 healthy women walking at the same slow speed as the RA patients were included as controls. The recordings were made while the subject walked on a treadmill with a computerized electrogoniometer measuring the angular excursions of the hip, knee and ankle in three planes simultaneously. The patients with RA walked at a slower speed than did the healthy subjects (0.6 vs 1.2 ms-1). The angular excursions, i.e. inward and outward rotation, abduction and adduction, flexion and extension, were significantly less in the RA patients than in the healthy subjects who walked at voluntary speed. As compared to the healthy subjects walking at a slow speed, the differences in range of motility were much smaller. The major aberrations of the gait pattern were found in the ankles and feet, which showed reduced internal rotation (7 vs 10 degrees), adduction (6 vs 12 degrees) and a less pronounced plantar flexion at toe off (1 vs 8 degrees).