Capturing Quality Clinical Videos for Two-Dimensional Motion Analysis

Introduction: Motion analysis, particularly two-dimensional (2D) analysis, can be a useful tool for prosthetists and orthotists in their clinical practice as it provides a mechanism by which improvements in motion as a result of device use may be documented and quantified. However, usefulness of video-based 2D analysis is contingent on recording quality clinical videos using a standardized protocol. Materials and Methods: The purpose of this work was to provide practical tips for taking quality clinical videos for use in 2D motion analysis intended to enhance evidence-based practice. Conditions that affect the quality of the video include illumination, image size, camera position, steadiness of the camera, and marker placement on the patient. A bright image is needed to track the joints or segments. The camera needs to be held steady, level, and placed perpendicular to the image field. The camera should be as close as possible to the image field while maintaining sufficient space to view the activity. Correct marker placement on the joints of interest improves measurement of joint angles. Results and Conclusions: Good quality videos as part of 2D motion analysis can result in data that are comparable to that of instrumented motion analysis systems when used for 2D analysis, enhancing clinician’s evidence-based practice. Care must be taken during the setup process and during data capture to ensure that the resulting video is recorded in a manner that is appropriate with respect to patient privacy concerns.