Ligament Strain Response Between Lower Extremity Contralateral Pairs During In Vitro Landing Simulation

Area of Science:

• Biomechanics
• Orthopedic Research
• Sports Medicine

Background:

• Limb asymmetries are known risk factors for anterior cruciate ligament (ACL) injuries.
• Previous studies found no significant ligament strain differences between contralateral limbs under identical simulated kinematics.
• The consistency of limb failure during impact simulation testing remains unexplored.

Purpose of the Study:

• To test the hypothesis that contralateral lower extremities do not exhibit side-to-side differences in ligament strains.
• To determine if failure loads and locations are independent of limb dominance.

Main Methods:

• Controlled laboratory study using 14 pairs of cadaveric lower extremities.
• A mechanical impact simulator recreated in vivo landing ground-reaction forces.
• Differential variable force transducers measured strains on the ACL and medial collateral ligament (MCL).

Main Results:

• No significant differences were found in peak ACL or MCL strain across 5 loading conditions.
• Limb dominance was independent of both load at failure and failure location.

Conclusions:

• No significant differences in ACL and MCL strain values between limb sides during in vitro impact simulation.
• Limb dominance does not influence the failure threshold of the ACL.
• Functional mechanics of the ACL are comparable between contralateral pairs from the same healthy specimen.