Exploring pre-impact landing kinematics associated with increase and decrease in the anterior cruciate ligament...

Area of Science:

• Biomechanics
• Sports Medicine
• Orthopedics

Background:

• Anterior cruciate ligament (ACL) injuries are common in female athletes, particularly during single-legged landings.
• Understanding pre-impact landing kinematics is crucial for injury prevention strategies.
• Previous research has not fully elucidated the specific kinematic factors contributing to ACL injury risk in female athletes.

Purpose of the Study:

• To identify single-legged landing kinematic characteristics associated with increased or decreased anterior cruciate ligament (ACL) injury risk in female handball players.
• To evaluate the discriminative ability of pre-impact landing kinematics in predicting future ACL injuries.
• To explore the relationship between specific kinematic components and knee valgus torque during landing.

Main Methods:

• Principal Component Analysis (PCA) was used to decompose pre-impact landing kinematics into distinct kinematic components (KCs).
• Linear Discriminant Analysis (LDA) was applied to KC scores to identify significant KCs differentiating injured from non-injured legs.
• A motion-equation-based model was used to predict knee valgus torque based on hypothetical pre-impact kinematics.

Main Results:

• A combination of the second major KC (knee flexion/extension and angular velocity) and minor KCs (torso medial/lateral leaning) accurately discriminated between injured and non-injured legs (12.5% error rate).
• These discriminating KCs significantly influenced frontal-plane knee loading patterns, as predicted by the motion-equation-based model.
• Specific pre-impact landing postures, characterized by KC-based analysis, were linked to knee valgus torque and potential ACL injury risk.

Conclusions:

• Pre-impact single-legged landing kinematics, particularly knee and torso movements, can predict future ACL injury risk in female athletes.
• KC-based postural characterization offers a valuable tool for assessing ACL injury risk.
• Motion-equation-based knee stress quantification, combined with kinematic analysis, can enhance the understanding of ACL injury mechanisms.