The effect of electrical stimulation on quadriceps femoris muscle torque in children with spina bifida.

The effects of neuromuscular electrical stimulation (NMES) on the torque production of the quadriceps femoris muscles were examined in five children with spina bifida. Two male subjects, aged 5 and 12 years, and three female subjects, aged 5, 12, and 21 years, participated in the study. Surface stimulation was applied to the quadriceps femoris muscles of one lower extremity for 30 minutes each day over an 8-week period. At 0, 4, and 8 weeks, maximum isometric voluntary knee extension torques were measured for both control and stimulated lower extremities with a dynamometer at 0, 15, 30, 45, and 60 degrees of knee flexion. The three oldest subjects had torque measurements of acceptable reliability (intraclass correlation coefficient greater than .72). Two of these three subjects also had significant increases in the torque produced by the stimulated limb relative to the torque produced by the control limb. The data were unreliable from the two youngest subjects. Completion times for functional tasks (walking and step ascension/descension) were also recorded before and after the 8 weeks of stimulation. The completion times were lower following stimulation for four subjects.