Use of multimedia for gait analysis

A comprehensive package for gait analysis, Motion Toolbox is presented. Compressed digital video is recorded and analysed on an ordinary desktop Macintosh computer, together with a domestic video camera or camcorder. Kinematics are derived following digital filtering, and joint kinetics calculated by two-dimensional link-segment inverse dynamics. Graphs of these quantities can then be plotted beneath the video, forming a direct link between the data and the corresponding picture in the video. Intuitive representation of joint kinetics is facilitated by muscles being drawn directly onto the video. Data may also be imported from commercial biomechanical measuring equipment, such as 3D motion analysis systems and electromyography. Motion Toolbox has been in use for three years, and stimulated the inauguration of an email list and web-site for Clinical Gait Analysis. Clinical cases are presented, complete with physical examination and biomechanical findings, and discussed by over 500 subscribers to the list, forming a database of current opinion. A telematics service is also available, whereby digital video of a patient can be sent by email to the author, and the results returned with an expert interpretation. This provides a useful service for the clinician isolated from the facilities of a conventional gait laboratory.