Anatomic double bundle ACL reconstruction outperforms any types of single bundle ACL reconstructions in controlling...

Area of Science:

• Orthopedic Surgery
• Biomechanics
• Sports Medicine

Background:

• Anterior cruciate ligament (ACL) injuries are common, often leading to knee instability.
• Restoring dynamic rotational knee laxity is crucial for optimal functional outcomes after ACL reconstruction.
• Different surgical techniques exist, including single-bundle (SB) and double-bundle (DB) reconstructions, with varying graft placements.

Purpose of the Study:

• To compare the effectiveness of anatomic single-bundle (SB), conventional SB, and anatomic double-bundle (DB) ACL reconstructions in restoring dynamic knee laxity.
• To evaluate rotational laxity using tibial acceleration measurements during a pivot shift test.

Main Methods:

• Sixteen cadaveric knees underwent ACL resection and subsequent reconstruction with three techniques: anatomic SB (n=8), conventional SB (n=8), and anatomic DB (n=8).
• A manually performed pivot shift test was used to assess dynamic rotational laxity.
• Tibial acceleration was measured using a triaxial accelerometer before and after ACL procedures.

Main Results:

• ACL deficiency significantly increased tibial acceleration compared to intact knees (p < 0.0001).
• Anatomic double-bundle (DB) ACL reconstruction successfully reduced acceleration to levels comparable to intact knees (non-significant difference).
• Both anatomic and non-anatomic single-bundle (SB) reconstructions failed to restore dynamic rotational laxity to the level of intact knees (p=0.0002 for non-anatomic SB, p < 0.0001 for anatomic SB).

Conclusions:

• Anatomic double-bundle (DB) ACL reconstruction demonstrates superior restoration of dynamic rotational knee laxity compared to single-bundle (SB) techniques.
• The graft placement (anatomic vs. non-anatomic) did not enable SB reconstructions to match the rotational stability achieved by DB reconstruction.
• Anatomic DB reconstruction is recommended for patients experiencing rotational laxity issues after ACL injury.