Variability Of Gait Parameters In Patients With Multiple Sclerosis

Abstract

Patients with Multiple Sclerosis (MS) often complain of fluctuation in their symptoms and movement patterns that they frequently attribute to fatigue. In order to determine the ef.cacy of treatments aimed at improving movement coordination, it is necessary to understand the variability of motor function associated with the disease. PURPOSE To determine the within- and between-day variability of gait mechanics in subjects with MS compared to healthy controls. It was hypothesized that the MS subjects would be more variable than the healthy controls and that there would be within- and between-day differences in variability. METHODS Five gait analysis sessions were performed on each of 20 subjects with MS (age 43.0 ± 9.6 yrs, height 166. 6± 9.0cm, mass 79.7 ± 19.3kg) and 8 healthy controls (age 40.9 ± 8.6yrs, height 167.4 ± 14.6cm, mass 72.6 ± 14.2kg). Three data collections took place in the morning and afternoon of one day (AM1, PM Fresh, PM Fatigue) and the final two collections took place one week later in the morning only (AM2 Fresh, AM2 Fatigue). Gait cycles for each condition were time normalized to the stride cycle (100 data points). The standard deviations (SDs) of fifteen stride cycles for kinematic data were calculated for each point and then averaged to determine the measure of variability for the sagittal plane angles at the ankle, knee, and hip. For the kinetic data, the SDs of three gait cycles were calculated and the average during stance was used as the measure of variability for vertical ground reaction forces and sagittal plane moments and powers at the ankle, knee and hip. Two-way ANOVAs (group × condition) with repeated measures were used to assess the differences in variability. RESULTS Kinematic and kinetic gait variability was not different across conditions for the MS group. However, the MS group had significantly more joint angle variability (p < 0.05) than the control group at the hip (1.85 ± 0.45 vs. 1.62 ± 0.32 deg), knee (2.59 ± 0.69 vs. 2.19 ± 0.35 deg), and ankle (1.48 ± 0.35 vs. 1.30 ± 0.21 deg). Kinetic variability was not different between groups. CONCLUSION In general, MS subjects have greater kinematic variability than healthy control subjects. Supported by the University of Delaware Center for Research Development