Greater Rotational Knee Laxity Observed at Second-Look Arthroscopy in Patients With Failed Meniscal Repair Performed at the Time of Anterior Cruciate Ligament Reconstruction.

PURPOSE

To evaluate the healing of meniscal repair performed concomitantly with anterior cruciate ligament reconstruction (ACLR) using second-look arthroscopy, as well as the relationship between meniscal healing and knee laxity using quantitative evaluation under anesthesia.

METHODS

This retrospective study included patients who underwent primary double-bundle ACLR with meniscal repair between June 2016 and June 2021, with a 2-year minimum follow-up. Meniscal healing was evaluated by second-look arthroscopy at least 1 year postoperatively, and knee laxity was measured under general anesthesia preoperatively, intraoperatively, and at second-look arthroscopy.

RESULTS

Of 562 knees treated with ACLR, 113 knees, with 137 meniscal repairs, were analyzed. Second-look arthroscopy classified 114 menisci (83.2%) as healed and 23 (16.8%) as failed. The side-to-side difference in anterior tibial translation (ATT) and the side-to-side ratios of tibial acceleration and external rotational angular velocity (ERAV) improved intraoperatively in both groups (ATT, 6.0 to -1.0 mm [P < .001] and 6.0 to -1.0 mm [P < .001]; acceleration, 5.1 to 1.2 and 4.9 to 1.1 [P < .001]; ERAV, 3.6 to 1.3 and 3.6 to 1.6 [P < .001]). There were no significant differences in ATT and patient-reported outcome measures, including the Lysholm score and Knee Injury and Osteoarthritis Outcome Score (KOOS), between the groups. The proportion of patients achieving the minimal clinically important difference for the Lysholm score and KOOS did not differ significantly between the groups. However, at 1 year postoperatively, acceleration and ERAV were higher in the failed group than in the healed group (P < .001).

CONCLUSIONS

Patients with failure of meniscal repair performed concomitantly with ACLR showed significantly greater rotational knee laxity at the time of second-look arthroscopy. These patients exhibited significantly higher preoperative and postoperative pivot-shift grades than those who did not experience failure of meniscal repair. There were no significant differences in ATT and patient-reported outcome measures between the groups.

LEVEL OF EVIDENCE

Level Ⅲ, retrospective comparative study.