Analysis of ankle inversion sprain injury mechanism from accidental injury cases captured in televised basketball matches

Methods An ankle inversion sprain injury occurred in a televised basketball match was found from the internet. The videos were transformed into uncompressed AVI image sequence by using Adobe Premiere Pro (CS4, Adobe Systems Inc, San Jose, California). Then the image sequences were synchronized and rendered into 1-Hz video sequences by Adobe After-Effects (CS4, Adobe Systems Inc). 3-dimension animation software Poser 4 and Poser Pro Pack (Curious Labs Inc, Santa Cruz, California) were used to perform the matching part. Virtual environment was built according to the real dimensions of a basketball court and it was manually matched to the background for each frame in every single camera view. The skeleton model from Zygote Media Group Inc. (Provo, Utah) was used to match with the athlete. The segment dimensions were adjusted according to the subject’s height. The skeleton matching started with the hip, thigh, shank segment and then distally matched the foot and toe segments frame by frame. The ankle time histories were input into Microsoft Excel (Microsoft Office, Microsoft, US) to calculate the velocity-related information. Results The peak inversion in this case lies within the range (48°-142°) obtained in previous studies [1]. Different from previous studies [1], plantarflexion is found at the time of peak ankle inversion during the injuring motion.