Softball players with shoulder injuries exhibit upper-body compensatory strategies compared to healthy controls: a wearable inertial sensors study

The aim of the study was to assess the kinematic differences in the upper limb and trunk between healthy and shoulder-injured softball players. Eleven first-division softball players (mean age 25.9±8.1) were enrolled. Five players experienced a shoulder injury with consequent surgery. The players were assessed while performing a standard throw, from the moment when they pick up a ball on the ground (Pick-up Phase) to the complete throw (Pass Phase), using 11 wearable inertial sensors (Xsens MTw Awinda). Peak joint kinematics and range of motion (ROM) were analysed. The shoulder-injured players showed less shoulder internal/external rotation (p<0.01) and flex-/extention (p<0.01), elbow flex-/extension (p<0.01), trunk tilt (p<0.01) ROMs than healthy ones. Injured players performed voluntarily or unwittingly the movement in a more conservative way.