Double-bundle ACL surgery demonstrates superior rotational kinematics to single-bundle technique during dynamic task.

Area of Science:

• Orthopedic surgery
• Biomechanics
• Sports medicine

Background:

• Anterior cruciate ligament (ACL) rupture often leads to residual rotational knee instability after traditional single-bundle repair.
• Double-bundle ACL reconstruction shows promise for improved rotational restraint compared to single-bundle techniques.
• Previous comparisons were limited to passive conditions, not dynamic, weight-bearing activities.

Purpose of the Study:

• To compare rotational knee kinematics between single-bundle and double-bundle ACL reconstruction techniques.
• To evaluate these differences under physiological, weight-bearing, dynamic conditions.
• To assess post-operative kinematics against uninjured controls.

Main Methods:

• Twenty-two patients with isolated ACL ruptures were randomized to single- or double-bundle reconstruction.
• Three-dimensional knee kinematics were captured during a dynamic cutting task.
• Pre- and post-operative rotational range of motion was compared between groups and with controls.

Main Results:

• No significant difference in overall rotational range of motion was observed under physiological loading.
• A significant shift towards external rotation occurred in the single-bundle group post-surgery.
• The double-bundle group's rotational kinematics more closely approximated those of uninjured controls.

Conclusions:

• Double-bundle ACL reconstruction provides superior rotational knee kinematics compared to single-bundle reconstruction.
• This improvement is evident under dynamic, weight-bearing conditions.
• Double-bundle technique better restores normal rotational knee function post-operatively.