Interobserver variability of gait analysis in patients with cerebral palsy

In this study 11 ambulatory patients (mean 10.8 years) with spastic cerebral palsy were each evaluated with instrumented gait analysis at four different centers. After review of the data, each medical director chose from a list of treatment options. The average variability in static range of motion from physical examination ranged from 25 degrees to 50 degrees. Hip and knee sagittal motion had the best relative variability of 20 degrees to 24%. Via gait analysis, the average variability in sagittal, coronal, and transverse plane kinematic motions averaged 12, degrees 7 degrees, and 20 degrees, respectively. Increased variability was noted in transverse (worst) to coronal and finally sagittal (best) plane motion. Only two mildly affected patients had similar, but not exact, treatment recommendations. The authors conclude that substantial variations in raw data exist when the same cerebral palsy patient is evaluated at different gait centers. These data do not yield the same treatment recommendations in the majority of patients.