A shockwave approach for web-based clinical motion analysis.

Abstract

Advances in Internet connectivity and personal multimedia computing have created opportunities for integrating simple motion analysis into clinical practice. The Macromedia Shockwave environment provides tools for creating media-rich software that runs within a Web browser. For this project, clinical motion analysis software was created using Shockwave that can load digital video clips of a client's motion, step/shuttle/play through the clip, superimpose a grid over the video image, measure relative joint angles, scale to a linear factor, measure distances, and measure average velocities. After installing the Shockwave and Quicktime video plug-ins, the Motion Analysis Tools-Shockwave program runs directly from a Web page hyperlink. Program testing involved comparing angle measurements, linear distances, stride length, and walking speed among six video clips. The first three clips were of a transtibial prosthesis being carried through the field of view (640 x 480, 320 x 240, 320 x 240 enlarged to 640 x 480). The second set of three clips was of a metal square carried through the field of view. Average root mean square errors were 2.0 degrees for angle measures and 1.2 cm for length measures. Stride length standard deviation was 4.6 cm (mean length = 212.1 cm). Average walking speed standard deviation was 0.015 m/s (mean speed = 1.15 m/s). The test results were consistent with video motion analysis results and within an acceptable range for clinical design-making. This Web-based motion analysis approach provides a useful tool for ubiquitous, quantitative, clinical gait analysis.