Gait patterns in patients with amyotrophic lateral sclerosis.

A study of 24 patients with amyotrophic lateral sclerosis (ALS) was done to evaluate the relationship between the disease state and walking performance. Each was filmed with high speed cameras as he/she walked at free speed. Spatial position of points on the limbs were quantified from films with a digitizer and a computer. Velocity, cadence, stride length, timing parameters, and joint patterns of the lower extremity were calculated with these data. Both cadence and stride length were seen to decrease as velocity decreased. Patients spent less time on one leg (single limb stance) and more time on two legs during walking as velocity decreased. No relationship was found between walking parameters and pulmonary function, type of neurologic symptoms, or number of months since diagnosis. The clinical feature that correlated best with walking performance was lower extremity muscle strength. Stride length was decreased in the slower walkers by a decrease in hip excursion into flexion and extension, excessive knee flexion at initial contact, and diminished plantarflexion at weight release.