Gait electromyography in children with myelomeningocele at the sacral level

Objective: Patients with sacral level myelomeningocele can be expected to maintain a high level of ambulatory status long into adulthood. Gait deterioration and knee pain reported in this population may be attributed to compensatory movements and increased recruitment of less affected muscle groups to achieve this desired level of ambulation. The objective of this study was to analyze the effect of the solid ankle-foot-orthoses (AFOs) on the muscular activity of selected muscles during walking. Design: Cohort/outcome. Setting: Laboratory. Patients: Twenty four patients with sacral level myelomeningocele between 4 to 17 years of age. Intervention: Electromyographic activity of selected muscle groups were studied during barefoot walking and walking with solid AFOs at a self-selected walking velocity. Main Outcome Measures: Timing of electromyographic activity and sagittal plane knee kinematics. Comparison to normal elcctromyographic patterns and changes between barefoot and AFO walking conditions. Results: With the AFOs there was significantly less prolonged stance phase quadriceps activity compared with barefoot walking, although greater than normal activity persisted. There was no change between conditions for the other monitored muscle groups. All muscles elicited greater duration of activity over the course of the gait cycle. Conclusions: Our results show that solid AFOs improve the prolonged knee extensor activity evident for barefoot walking. This is clinically relevant to the gait deterioration and knee pain sometimes seen in this patient population. We espouse early and persistent orthotic intervention to reduce compensatory muscular overactivity and maintain gait quality.