Anatomic and Biomechanical Investigation on ACL: A Cadaveric Study

The present study was aimed to investigate the kinematics differences between round-tunnel (ROT) and flat-tunnel (FLT) techniques and compare the influence to the anterior root of lateral meniscus (ARLM ) in anterior cruciate ligament (ACL) reconstruction when using hamstring graft.

Nine matched pairs of fresh-frozen cadaveric knees were evaluated for the kinematics of intact, ACL-sectioned, and either ROT or FLT reconstructed knees. The graft bundles for FLT technique were separately tensioned. A 6 degrees of freedom robotic system was used to assess knee laxity: (1) 134-N anterior tibial load at 0°, 15°, 30°, 60°, and 90°of knee flexion. (2) 10-Nm of valgus torque followed by 5-Nm of internal rotation torque simulates a pivot-shift test at 15°, 30°. (3) 5-Nm internal and external rotation torques at 0°, 15°, 30°, 60°, and 90°. (4) 10-Nm varus and valgus torques at 15°, 30°. Coverage of ACL tibial footprint and areas of ARLM attachment before and after reaming were measured using three-dimensional isotropic MRI scanning.

Nine matched-paired fresh frozen human cadaveric knees were randomly distributed into two groups: Flat-tunnel (FLT) group and round-tunnel (ROT) group. One knee from each pair was reamed with flat tunnel, while the contralateral knee was reamed with round tunnel.

10-Nm of valgus torque followed by 5-Nm of internal rotation torque simulates a pivot-shift test at 15°, 30° of knee flexion

134-N anterior tibial load simulates a KT-2000 arthrometer at 0°, 15°, 30°, 60°, and 90°of knee flexion

Coverage of ACL tibial footprint and areas of ARLM attachment before and after reaming were measured using three-dimensional isotropic MRI scanning post-operation

Inclusion Criteria: intact knee with no previous injures Exclusion Criteria: those with ligamentous injury or a limited range of motion