Favorable outcomes after all-inside repair of complete lateral meniscus oblique radial tears in patients undergoing anterior cruciate ligament reconstruction: A case-series study.

Abstract

To evaluate the outcomes of repairing lateral meniscus oblique radial tears of the posterior horn (LMORT) that are complete and originate >1 ​cm from the posterior root (type 4), during anterior cruciate ligament reconstruction (ACLR) at a minimum of 2 years of follow-up. In this case series (March 2018-March 2023), we included adults undergoing primary ACLR with type 4 LMORT all-inside repair and complete ≥2-year postoperative complication data. We assessed change from baseline and minimal clinically important difference (MCID) rate for the Patient Reported Outcome Measures Information System Pain Interference (PROMIS-PI) and Mobility (PROMIS-MO), International Knee Documentation Committee Subjective Knee Form (IKDC), Activity Rating Scale (ARS) and Single Assessment Numeric Evaluation (SANE). Return-to-sport (RTS), same-level RTS and complication (retear of lateral meniscus, reoperation, ACLR graft failure, infection, contralateral knee surgery) rates were reported. When available, we evaluated second-look arthroscopy and postoperative magnetic resonance imaging (MRI) findings. In 16 cases (median follow-up; 37.3 [29.1-65.3] months), improvement was noted in median PROMIS-PI (60.3 [57.7-65.8] vs 43.0 [39.0-48.9]; p ​< ​0.001), PROMIS-MO (38.5 [33.5-40.8] vs 61.1 [54.0-66.8]; p ​< ​0.001), IKDC (42.0 [23.5-48.0] vs 91.4 [82.8-96.6]; p ​< ​0.001) and SANE (25.0 [10.0-38.3] vs 89.0 [80.0-95.0]; p ​= ​0.002). No statistically significant differences were observed for ARS (16.0 [13.0-16.0] vs 12.0 [8.0-14.5] p ​= ​0.099). MCID rates were 85.7 ​%, 92.9 ​%, 100 ​%, 57.1 ​% and 78.6 ​% for PROMIS-PI, PROMIS-MO, IKDC, ARS and SANE, respectively. RTS and same-level RTS rates were 12/14 (85.7 ​%) and 8/14 (57.1 ​%), respectively. Three (18.8 ​%) patients underwent ipsilateral knee reoperations; none for lateral meniscus retears. There was one (6.3 ​%) contralateral knee operation. Complete LMORT repair healing was observed on available second-look arthroscopies and MRIs. Our study of patients with type 4 LMORT repair during ACLR supports the limited existing evidence by demonstrating statistically significant improvement in patient-reported outcome measures, low complication rates and satisfactory healing patterns. Our findings should further encourage all-inside repair of type 4 LMORTs during ACLR, as it results in high RTS and substantial same-level RTS. IV. Case-series.