Additional lateral meniscus centralization reduces residual anterolateral rotatory instability after anterior cruciate ligament reconstruction and lateral meniscus repair

Purpose This study aimed to examine the effects of lateral meniscus (LM) centralization on anterolateral rotational stability in patients with anterior cruciate ligament (ACL) and LM injuries. The hypothesis was that performing LM repair and centralization on knees with LM lesions would control anterolateral rotatory instability (ALRI). Methods Twenty patients with ACL and LM injuries were enroled. Tibial acceleration in the pivot shift was quantified using a triaxial accelerometer at each preoperative and intraoperative time point (after ACL reconstruction (ACLR), LM repair and centralization) of double‐bundle ACLR. Pivot shift was assessed with the ACL graft tension provisionally fixed under two conditions that both the anteromedial bundle (AMB) and posterolateral bundle (PLB) grafts were temporarily fixed at 5 N each (A5P5) and at 10 N each (A10P10). The Kruskal–Wallis test was used to compare the tibial accelerations between each time points, and the Steel–Dwass test with Bonferroni correction was used for multiple comparisons. Also, patient factors associated with the results of a higher‐grade pivot shift compared to the healthy side after ACLR and LM repair were determined in a two‐group comparison. Results Pivot shift acceleration was significantly decreased after ACLR (PreOP [8.3 ± 2.1 m/s 2 ] vs. ACLR [5.1 ± 2.1 m/s 2 ] in A5P5, p < 0.01 and [4.6 ± 1.5 m/s 2 ] in A10P10, p < 0.01). However, the subsequent LM repair did not significantly reduce the pivot shift (ACLR [5.1 ± 2.1 m/s 2 ] vs. LM repair [4.0 ± 0.9 m/s 2 ] in A5P5, p = 0.09 and ACLR [4.5 ± 1.5 m/s 2 ] vs. LM repair [3.5 ± 1.0 m/s 2 ] in A10P10, p = 0.10). Additional centralization significantly controlled the residual pivot shift in most cases (ACLR [5.1 ± 2.1 m/s 2 ] vs. Centralization [2.9 ± 1.0 m/s 2 ] in A5P5, p < 0.01 and ACLR [4.5 ± 1.5 m/s 2 ] vs. Centralization [2.8 ± 0.8 m/s 2 ] in A10P10, p < 0.01). Conclusion For patients who did not achieve sufficient rotational control after ACLR and LM repair, adding LM centralization further controlled ALRI in a relatively minimally invasive procedure. Level of Evidence Level III.