Drop Vertical Jump Biomechanics Differ In Athletes Post-concussion: Implications For Concussion Detection And Rehabilitation

Athletes recovering from concussions face cognitive impairments predisposing them to higher risk for lower extremity injuries including anterior cruciate ligament (ACL) tears. Current concussion detection methods are limited by observer interpretation and intentional underperforming on baseline testing (sandbagging). Kinematics can aid in objective concussion detection; however, studies investigating changes in jump landing kinematics from pre- to post-concussion are limited. PURPOSE: To investigate changes in lower extremity and trunk kinematics during a drop vertical jump (DVJ) in collegiate varsity athletes from pre- to post-concussion. METHODS: 20 collegiate varsity athletes performed 3 DVJs at the preseason assessments directly before and after sustaining a concussion, captured by a Kinect V2 device. Specific DVJ parameters (Table 1), and the standard deviation of each parameter across a participant’s 3 jump (inter-jump variability, IJV), were compared between pre- and post-concussion using a paired one-sided t-test. Statistical significance was set at P < .05. RESULTS: Peak sagittal angle of left and right knees decreased significantly post-concussion, indicating less knee flexion (105.66° vs 91.74°, P = .011; 105.01° vs 91.30°, P = .013). Maximum spine sway in the X axis decreased significantly from 4.37° to 3.41° (P = .048). IJV of peak sagittal angle increased significantly in both knees (5.81° vs 15.71°, P < .01; 4.63° vs 15.29°, P < .01). IJV of spine sway variability in the Z axis and maximum ankle distance increased significantly (0.42° vs 0.72°, P = .024; 0.017 m vs 0.029 m, P = .022). CONCLUSIONS: Multiple DVJ parameters change significantly in collegiate varsity athletes post-concussion. Notably, decreased peak sagittal angle has been associated with increased risk for ACL tear. The DVJ is a potentially valuable tool for objective concussion detection and guiding post-concussion rehabilitation to reduce the risk of ACL tears. Supported by: This work was supported by MEDTEQ+, Emovi Inc., and Semperform inc.