Arthroscopic Repair of Meniscal Medial Root Tears: The Necessity of Concomitant Realignment Osteotomy.

INTRODUCTION: Posterior medial meniscal root tears (PMMRTs) are biomechanically similar to meniscectomy and often occur in middle-aged women with low-energy trauma. The literature reports consistently high failure rates, meniscal extrusion, and early progression of osteoarthritis following isolated arthroscopic repair in varus-malaligned knees, while isolated arthroscopic repair is reported to have good outcomes in well-aligned knees. The need for concomitant high tibial osteotomy (HTO) to protect root repair in varus knees is an ongoing controversial topic with emerging high-quality evidence. MATERIALS AND METHODS: The PubMed/MEDLINE, Embase, Cochrane Library, and Scopus databases were searched from January 2019 to June 2026 for articles to be included in the narrative review, with additional landmark pre-2019 articles included. The searched terms used were: Medical Subject Headings: "Meniscal root tear" AND "high tibial osteotomy" AND "meniscal extrusion" AND "varus malalignment" AND "posterior medial meniscus" AND "knee osteoarthritis". Original articles, systematic reviews, meta-analyses, and consensus statements were included, but preprints, opinion pieces, and predatory journal sources were not. RESULTS: PMMRTs accounted for 2.2-9.8% of all knee magnetic resonance imaging (MRI) examinations, and approximately 90% occurred in the posterior horn of the medial meniscus, with a majority of these occurring in overweight women aged 50-60 years. Hoop stress was eliminated with detachment of the roots, and the resulting tibiofemoral contact pressure was comparable to that of total meniscectomy. Isolated repair was associated with an 88.5% rate of MRI failure and a 2.37-fold increased risk of progression of knee osteoarthritis in varus-aligned knees compared to neutral alignment knees. HTO combined with meniscal root repair (HTO-MRR) resulted in significantly improved Hospital for Special Surgery and International Knee Documentation Committee scores compared with HTO alone (n = 725). HTO-MRR has been found to heal between 13% and 93%, whereas isolated repair was 0-50%. A criterion of ≥5° of correctable varus was the most commonly reported one for concomitant realignment. CONCLUSION: Concomitant HTO with arthroscopic root repair in varus (≥5°) patients, especially those <65 years, with Kellgren-Lawrence ≤2, is the most suitable joint preserving option. Long-term randomized controlled trials or registry studies are required to establish the upper limits of benefit and to establish subgroups that might benefit from isolated repair with centralization augmentation.