The results suggest that there are notable differences between 2D video and electrogoniometry assessed knee
flexion angles during a jumping and landing task. The present knee flexion angle differences between El-Gon and video may be explained by crosstalk errors, axis location, and video perspective errors. If countermovement knee flexion angle, maximum landing knee flexion angle, and flexion angle at maximum ground reaction force are assessed using electrogoniometry, the slope, and intercept values (Table 1) can be used to compare to 2D video assessment methods. Despite the instrumentation differences, the El-Gon displayed reliable data at various discrete points of interest. Due to the ease of use and instantaneous data acquisition, the El-Gon could be used in sports/clinical settings to aid in performance evaluation and injury screening during relatively planar sagittal movements.
Future studies should assess the validity of using the El-Gon to assess both sagittal and frontal plane knee angles
during jumping and landing using 3D motion analysis as the criterion. Additionally, a quick and easy means to account for El-Gon cross-talk errors needs to be developed and tested on various electrogoniometers