Prospective Consecutive Clinical Outcomes After Transtibial Root Repair for Posterior Meniscal Root Tears: A Multicenter Study

BACKGROUND: Prospective evaluation of clinical outcomes after posterior meniscal root repair utilizing a transtibial pullout technique is limited, and factors that may contribute to outcomes are unclear. HYPOTHESIS: It was hypothesized that there would be an overall significant improvement in outcomes after root repair and that differences in clinical outcomes would correlate with age, body mass index (BMI), sex, and meniscal extrusion. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: Consecutive patients undergoing transtibial medial or lateral meniscal root repair were enrolled prospectively at 2 orthopaedic centers between March 2017 and January 2019. Pre- and postoperative magnetic resonance imaging (MRI) were obtained to assess for meniscal healing, quantification of extrusion, articular cartilage grade, and subchondral bone changes. Patient-reported outcomes including International Knee Documentation Committee (IKDC) scores, Tegner activity scale, and visual analog scale (VAS) for pain were collected preoperatively and 2 years postoperatively. Patients were then subdivided by clinical and demographic characteristics to determine factors associated with clinical outcomes. RESULTS: Included were 45 patients (29 female, 16 male; mean age, 42.3 ± 12.9 years; mean BMI, 31.6 kg/m(2)) who underwent 47 meniscal root repairs (29 medial and 16 lateral; 2 had both). Significant improvements at 2-year follow-up were seen in IKDC score (41.1 vs 78.4; P < .001), Tegner activity level (3 vs 4; P < .001), and VAS pain (2.8 vs 0.7; P < .001). BMI, preoperative malalignment, cartilage status, and progressive meniscus extrusion (Δ = 0.7 mm) did not have a negative impact on IKDC and Tegner scores 2 years postoperatively. Age greater than or equal to 50 years and extrusion pre- and postoperatively were associated with decreased Tegner scores. Progressive meniscal extrusion was associated with a decreased overall improvement in Tegner scores. CONCLUSION: Transtibial root repair for medial and lateral posterior meniscal root tears demonstrated significantly improved clinical outcomes at 2 years postoperatively. Increased age, increased BMI, cartilage status, and meniscal extrusion did not have a negative impact on short-term functional outcomes (IKDC), but age greater than or equal to 50 years and extrusion negatively influenced patient activity level (Tegner). REGISTRATION: NCT03037242 (ClinicalTrials.gov identifier).