Clinical, Radiographic, and Arthroscopic Outcomes of Surgical Repair for Radial and Avulsed Lesions on the Lateral Meniscus Posterior Root During ACL Reconstruction: A Systematic Review

BACKGROUND: Clinical outcomes of surgical repairs for tears of the lateral meniscus posterior root (LMPR) in patients undergoing anterior cruciate ligament (ACL) reconstruction (ACLR) have not been comprehensively investigated. PURPOSE: To systematically review the clinical, radiographic, and arthroscopic results of surgical repairs for tears of the LMPR in patients undergoing ACLR. STUDY DESIGN: Systematic review; Level of evidence, 4. METHODS: A systematic electronic search of the PubMed and Embase databases was performed to identify studies reporting clinical, radiographic, or arthroscopic results of surgical repairs for tears of the LMPR in patients undergoing ACLR. Each included study was abstracted regarding study characteristics, patient characteristics, surgical technique, and outcome measures. The methodological quality of the included studies was analyzed according to the Methodological Index for Non-Randomized Studies (MINORS) criteria. RESULTS: Nine studies were included in this systematic review, representing a total of 215 knees in 215 patients. Overall, 123 side-to-side repairs and 89 pullout repairs were performed for tears of the LMPR during ACLR. After a mean follow-up of 33.9 months, significant improvements (P < .05) were found in the mean Lysholm score (from 58.3 to 91.4) as well as the mean International Knee Documentation Committee subjective score (from 61.1 to 87.2). Weightbearing anteroposterior radiographs of 41 patients showed no significant narrowing of lateral joint space width. On magnetic resonance imaging scans, 31 patients demonstrated no significant progression of chondral lesions, and no significant decreases in meniscal extrusion on coronal planes were reported in another 76 patients. The complete/partial healing was 93.6% on second-look arthroscopy after side-to-side repairs for radial tears of the LMPR. The MINORS value showed a high risk of bias for all 9 studies. CONCLUSION: Patients with tears of the LMPR associated with ACL injuries achieved favorable functional scores after ACLR and LMPR repairs, and the side-to-side repair for radial tears of the LMPR succeeded in a high meniscal healing rate of >90%. However, the authors of this review were unable to definitively conclude whether LMPR repairs fully restore the hoop stress of the lateral meniscus.