Augmenting ACL Repair With Suture Tape Improves Knee Laxity: A Biomechanical Study

Area of Science:

• Orthopedic Surgery
• Biomechanical Engineering
• Sports Medicine

Background:

• Anterior cruciate ligament (ACL) repair is an alternative to reconstruction.
• Suture tape augmentation (STA) may be necessary for adequate ACL repair outcomes.

Purpose of the Study:

• Investigate the influence of STA on proximal ACL repair.
• Evaluate the effect of two suture tape fixation angles on knee kinematics.

Main Methods:

• Controlled laboratory study using 14 cadaveric knees.
• Robotic testing system evaluated kinematics under various loads (anterior tibial, pivot-shift, rotational).
• Tested knee states included intact ACL, ACL cut, repair only, and STA with fixation at 0° and 20° flexion.

Main Results:

• ACL repair alone did not restore intact ACL laxity.
• STA significantly decreased anterior tibial translation at multiple flexion angles.
• STA fixed at 20° flexion demonstrated biomechanical similarity to the intact ACL state under pivot-shift and rotational loads.

Conclusions:

• Suture repair alone is insufficient for proximal ACL tears.
• STA enhances knee laxity and ACL in situ forces, bringing them closer to intact levels.
• Fixation at 20° flexion is superior to fixation at full extension for STA.