The effects of a shank guide on cycling biomechanics of an adolescent with cerebral palsy: a single-case study.

Objective: To examine 3-dimensional lower-extremity joint kinematics and muscle activity during cycling with and without a shank guide for a single subject with spastic diplegic cerebral palsy (CP).

Design: Single case.

Setting: Pediatric referral hospital.

Participant: A 13-year-old adolescent with spastic diplegic CP and limited ambulation abilities.

Interventions: Not applicable.

Main Outcome Measures: Kinematic data were collected for 6 joint motions and electromyographic data for 7 muscles during 10- to 15-second trials. Average variability in the kinematic curves was calculated, and kinematic and electromyographic data were analyzed descriptively.

Results: With the guide, the subject cycled at 40.1+/-2.0 rpm compared with 13.7+/-4.0 rpm without it. In addition, there was less variability in the kinematic curves (P=.03) and muscles tended to turn on sooner and off later. These results indicate that this subject could cycle faster with the guide, which is desirable for cardiovascular health, and that there was a possible increase in motor control due to reduced needs to control excessive joint motions.

Conclusions: Based on these findings, a shank guide may allow some people with CP to cycle faster and provide improved joint kinematics.