An individualized linear model approach for estimating scapular kinematics during baseball pitching

Assessment of scapulothoracic and glenohumeral contributions to shoulder function during baseball pitching are limited by challenges in accurately measuring dynamic scapular orientation. A recently validated individualized linear model approach that estimates orientation based on measurable humerothoracic has yet be adapted for may improve upon currently recommended methods such as the acromion marker cluster (AMC). This study evaluates ability a pitching-specific estimate static positions throughout throwing motion comparing against palpation an AMC. Individualized models were created 14 collegiate pitchers determining orientations at arm postures their individual motions. Linear AMC compared intermediate test within excluded from creation. similar all axes while differed internal/external rotation anterior/posterior tilt cocking (p = 0.001, p 0.018) follow-through 0.003, 0.006). root mean square error (RMSE) values smaller than positions/axes. RMSE (2.8–6.3°) range published previously deemed acceptable, (5.1–15.8°) went beyond this range. The improves current methods. Future applications facilitate understanding how joint relate injury risks, rehabilitation, performance.