Slow-motion smartphone video improves interobserver reliability of gait assessment in ambulatory cerebral palsy.

PURPOSE

Structured visual gait assessment is essential for the evaluation of pediatric patients with neuromuscular conditions. The purpose of this study was to evaluate the benefit of slow-motion video recorded on a standard smartphone to augment visual gait assessment.

METHODS

Coronal and sagittal plane videos of the gait of five pediatric subjects were recorded on a smartphone, including four subjects with ambulatory cerebral palsy and one subject without gait pathology. Twenty-one video scorers were recruited and randomized to evaluate slow-motion or normal-speed videos utilizing the Edinburgh Visual Gait Score. The slow-motion group (N = 11) evaluated the videos at one-eighth speed, and the normal-speed group (N = 10) evaluated the same videos at normal speed. Interrater reliabilities were determined by calculating intraclass correlation coefficients for each group as a whole, for each Edinburgh Visual Gait Score item, and after stratification by evaluator experience level.

RESULTS

The slow-motion group exhibited an intraclass correlation coefficient of 0.65 (95% confidence interval: 0.58-0.73), whereas the normal-speed group exhibited an intraclass correlation coefficient of 0.57 (95% confidence interval: 0.49-0.65). For less-experienced scorers, intraclass correlation coefficients of 0.62 (95% confidence interval: 0.53-0.71) and 0.50 (95% confidence interval: 0.40-0.59) were calculated for slow motion and normal speed, respectively. For more-experienced scorers, intraclass correlation coefficients of 0.69 (95% confidence interval: 0.61-0.76) and 0.67 (95% confidence interval: 0.58-0.75) were calculated for slow motion and normal speed, respectively.

CONCLUSIONS

Visual gait assessment is enhanced by the use of slow-motion smartphone video, a tool widely available throughout the world with no marginal cost.

LEVEL OF EVIDENCE

level I, randomized study.