Posterior tibial slope and meniscal slope correlate with in vivo tibial internal rotation during running and drop jump.

PURPOSE: The relationship between tibial bony and meniscus anatomy and knee kinematics during in vivo, high-impact activities remains unclear. This study aimed to determine if the posterior tibial slope (PTS) and meniscal slope (MS) are associated with in vivo anterior-posterior translation and internal tibia rotation during running and double-leg drop jumps in healthy knees.

METHODS

Nineteen collegiate athletes performed fast running at 5.0 m/s on an instrumented treadmill and double-leg drop jump from a 60 cm platform while biplane radiographs of the knee were acquired at 150 Hz. Tibiofemoral kinematics were determined using a validated model-based tracking process. Medial and lateral PTS and MS were measured using magnetic resonance imaging (MRI).

RESULTS

In fast running, more internal tibia rotation was associated with greater PTS (ρ = 0.336, P = 0.039) and MS (ρ = 0.405, P = 0.012) in the medial knee compartment. In the double-leg drop jump, more internal tibia rotation was associated with greater PTS (ρ = 0.431, P = 0.007) and MS (ρ = 0.323, P = 0.005) in the medial knee compartment, as well as a greater PTS in the lateral knee compartment (ρ = 0.445, P = 0.005).

CONCLUSION

These findings suggest that the medial and lateral PTS and medial MS are associated with the amount of knee rotation during high-impact activities. These in vivo findings improve our understanding of ACL injury risk by linking bone and meniscus morphology to dynamic kinematics.