Movement Patterns During a Jump-Landing Task in Athletes After Sport-Related Concussion and Healthy Control Individuals

Abstract

Context: A relationship between a history of sport-related concussion (SRC) and lower extremity injury has been well established in the literature.

Objective: To determine if biomechanical differences existed during a double-limb jump landing between athletes who had been released to return to play after SRC and healthy matched control individuals.

Design: Cross-sectional study.

Setting: Health system-based outpatient sports medicine center.

Patients or other participants: A total of 21 participants with SRC (age = 15.38 ± 1.77 years, height = 169.23 ± 8.59 cm, mass = 63.43 ± 7.39 kg, time since release to return to sport after SRC = 16.33 ± 12.7 days) were compared with 21 age-, sex-, and activity-matched healthy participants serving as controls (age = 15.36 ± 1.73 years, height = 169.92 ± 11.1 cm, mass = 65.62 ± 12.08 kg).

Main outcome measure(s): Biomechanical performance during the double-limb jump landing was assessed using a motion-capture system and force plates. The average of 3 consecutive trials was used to calculate lower extremity joint kinetics and kinematics. The variables of interest were internal knee-extension moment, internal varus moment, and total sagittal-plane knee displacement for the dominant and nondominant limbs. Independent t tests were performed to examine the differences between SRC and control groups for the variables of interest.

Results: No differences existed between groups for the descriptive data. The SRC group demonstrated greater internal knee-extension moments in the dominant (-0.028 ± 0.009 Nm/kg, P = .003) and nondominant (-0.018 ± 0.007, P = .02) limbs. The SRC group also exhibited greater internal varus moments in the dominant (0.012 ± 0.004 Nm/kg, P = .005) and nondominant (0.010 ± 0.003, P = .005) limbs. For sagittal-plane knee displacement, the SRC group displayed less knee-flexion displacement in the dominant (-12.56 ± 4.67°, P = .01) but not the nondominant (-8.30 ± 4.91°, P = .10) limb.

Conclusions: Athletes who had been released for return to sport after SRC landed with greater knee valgus than healthy matched control participants.

Keywords: biomechanics; lower extremity injuries; mild traumatic brain injuries.