Injury risk of upper extremity in baseball pitchers: Kinetics perception

Fajar Awang Irawan, Chuang Long-Ren, Peng Hsien-Te


Upper extremity is the important part at the time in pitching, and every pitcher has a different style. Previous study showed increased pitch counts have been linked to increased complaints of shoulder and elbow pain in youth pitchers. The purpose of this study was to compare kinetics data of upper extremity on fastball, curveball, and slider potentially injuries. Twenty-four baseball pitchers participated in this study. After signed informed consent and placed forty-eight reflective markers on head, upper extremities and lower extremities, participant threw the ball fifteen time each pitch type five meters away from the pitching marker on standing position in indoor laboratory. Kinetic parameters were calculated using software (Motion Monitor) to compute the musculoskeletal human models using motion capture data. Parameter of torques and forces were calculated using Motion data. Repeated measurement ANOVA was used to test the effects of pitching phases. Only on forearm supination torque at arm acceleration phase was significant difference. Another eighteen parameters from arm cocking phase, arm acceleration phase, arm deceleration phase, and follow-through were no significant differences base on kinetics parameters data. Ground reaction force at fastball was greater than curveball and slider. Parameters of fastball also take the domination at arm cocking, arm acceleration, and follow-through. Only on arm acceleration curveball take over the domination of kinetics parameters compared to fastball and slider. Overall, fastball has more injury risk than curveball and slider in pitching phases. Increased kinetics parameter might be proven to have more injury risk. Interpretation data by analyzing functional anatomy can be more useful in early detection of pitching injuries.