Objective
The posterior horn lateral meniscus oblique radial tear (LMORT) was recently identified in 12% of acute anterior cruciate ligament (ACL) injuries. A descriptive classification as well as individual management strategies were suggested. However, patient reported outcomes specifically for LMORTs type 3 (incomplete LMORT that extended >10 mm from root) and type 4 patterns (complete LMORT >10 mm from root) have not been reported. The purpose of this study was to determine the 2 year functional outcomes after meniscal repair of type 3 and 4 LMORTs at the time of ACL reconstruction (ACLR) surgery.
Methods
A retrospective matched cohort study was performed in a single academic institution between January 2010 to December 2018. 35 patients who underwent primary ACL reconstruction (ACLR) with concomitant posterior horn LMORT types 3 and 4 repairs with a 2-year minimum follow-up were included. Functional outcomes, reoperations and ACL failures were compared with a 1:1 matched cohort of 35 patients with isolated ACLR with a 2-year minimum follow-up. Patients were matched by age ±5 years, surgery date ±1 year, and surgeon.
Results
Average age at time of surgery was 22 years. Mean follow-up period was 4.6±2.0 years vs 4.6±2.2 years for the ACLR+LMORT and isolated ACLR groups, respectively. One ACL graft failed in each group. There was a total of 3 reoperations per group, including 1 ACLR revision, 1 lysis of adhesion and 1 meniscus surgery. No posterior horn LMORTs repair failures were reported. Functional outcomes were comparable between the groups at minimum 2 year follow up (IKDC: ACLR+LMORT 93.6 ± 5.3 vs isolated ACLR 91.6±8.2, P = .216; Tegner Activity Score: ACLR+LMORT 6.4±1.3 vs isolated ACLR 6.1±1.5, P = .517).
Conclusion
Repair of type 3 and 4 LMORTs at the time of ACL reconstruction showed encouraging results for optimizing meniscus preservation and knee stability. Functional outcomes and reoperations at 2 years after type 3 and 4 LMORT repairs at the time of ACLR compared favorably to a matched cohort of isolated ACL reconstructions.