Biomechanical difference between anatomical single bundle anterior cruciate ligament reconstruction and anatomical single bundle anterior cruciate ligament reconstruction plus anterolateral ligament reconstruction have not been studied.
The purpose of this study was to compare rotational stability between anatomic single bundle ACL reconstruction and anatomic single bundle ACL reconstruction plus anterolateral ligament (ALL) reconstruction.
Study Design: Randomized control trial, cross over design
Materials And Methods
Five cadavers were recruited for the study. Four surgical intervention conditions were sequent performed, which were arthroscopic ACL cut, mini-open ALL cut, arthroscopic ACL reconstruction with ipsilateral quadruple hamstring graft and anatomic ALL reconstruction with contralateral semitendinosus graft. Computer assisted navigation and Telos stress device were measured the rotational and translational difference respectively after every surgical intervention. The knee was bent in 30 and 90 degrees as well as the rotation of the knee was put in neutral and fully internal rotation position. The data was collected and compared with the intact knee by statistical analysis.
There was no significant difference in anterior translation found with Telos stress device between ACL reconstruction and ACL reconstruction with ALL reconstruction in 90° flexion and neutral rotation (6.4 ± 2.6 mm vs 6.2 ± 2.2 mm, p > 0.05) and was not significantly different in 90° flexion and internal rotation (5.0 ± 3.5 mm vs 4.0 ± 2.7 mm, p > 0.05). For knee 30° flexion, anterior translation significantly increased in neutral rotation (5.2 ± 4.8 mm vs 7.0 ± 4.4 mm, p < 0.05) and internal rotation (3.8 ± 4.4 mm vs 6.0 ± 4.6 mm, p < 0.05).
Anatomic anterolateral ligament reconstruction could reduce anterior translation of the tibia at knee 90° flexion but had little effect in 30° flexion. It also showed the improvement of the rotational instability after ALL reconstruction. So, ALL reconstruction is a secondary stabilizer and might be advised to perform in chronic ACL injury with significant rotational instability or athlete who used the knee in extreme motion.