The effects of functional electrical stimulation on walking in hereditary and spontaneous spastic paraparesis

To investigate in people with spastic paraparesis (SP): 1) the factors contributing to foot drop and reduced toe clearance while walking; 2) short-term effects of bilateral functional electrical stimulation (FES) of the common peroneal nerve.

Long term (>0.5 years) users of FES with SP were compared to matched controls (N = 11 per group). Ankle strength and plantarflexor stiffness and walking kinematics were objectively recorded. The effects of FES on: 1) perceived efficacy; 2) muscle torque and ankle motion; 3) clinical outcome measures and walking kinematics were assessed. Results were compared using an analysis of covariance.

Ankle weakness and stiffness is higher among people with SP. Higher plantarflexor stiffness is associated with reduced swing phase dorsiflexion; higher toe clearance while walking is associated with increased hip flexion. FES increases dorsiflexor torque, improves toe clearance and dorsiflexion in swing phase, and significantly improves walking speed (p < 0.05).

There are multiple causes of tripping in people with SP; FES reduces foot drop and improves walking speed.