PURPOSE: To compare the time-zero stability of an anatomic anteromedial (AM) single-bundle ACL reconstruction to an anatomic central (CTR) single-bundle ACL reconstruction.METHODS: Twelve (6 paired) hip to knee cadaveric specimens were studied. Using custom ACL computer navigation software, a Lachman test and a previously validated, navigated mechanized pivot shift test were performed on 4 separate experimental groups in each specimen: (1) intact ACL, (2) ACL deficient with total medial and lateral meniscectomy, (3) following anatomic AM single-bundle ACL reconstruction, and (4) after anatomic CTR single-bundle ACL reconstruction. Maximum anterior tibial translation in each group was measured.RESULTS: Lachman: No significant difference was observed between the AM and CTR reconstructions (n.s.) or between reconstruction and the intact ACL (3.4 ± 1.7 mm) (n.s.). Pivot Shift: Both the AM and CTR ACL reconstructions significantly reduced anterior translation relative to the ACL/menisci-deficient condition (lateral compartment: 8.9 ± 3.8 mm and 6.75 ± 4.6 mm vs. 17.25 ± 3.5 mm, respectively; P < 0.001 and medial compartment: -3.0 ± 5.3 mm vs. -3.7 ± 5.7 mm vs. 6.2 ± 6.7 mm, P < 0.05). There was also a significant difference between the AM (P < 0.001) and CTR (P < 0.05) ACL reconstructions and the intact ACL (2.8 ± 4.4 mm) for lateral compartment translation. Further, no difference was found between lateral or medial compartment translations in the AM versus CTR reconstructions (n.s.).CONCLUSIONS: It has been shown that there was no difference in the time-zero biomechanical stability between an anatomic anteromedial and anatomic central single-bundle ACL reconstruction. Given the current debate on the best anatomic ACL reconstruction technique, anatomic socket position in either the anteromedial or central locations provides similar time-zero biomechanics.
Anterior Cruciate Ligament Anterior Cruciate Ligament Reconstruction