Summary
This randomized controlled trial found that Arthroscopic Matrix-Based Meniscus Repair (AMMR) significantly improves radiological healing rates and may reduce the need for revision surgery compared to classic meniscal sutures (CMS) in treating meniscal tears in the avascular zone, though patient-reported outcomes were similar between the two groups after a minimum of two years of follow-up.
Abstract
Background
Meniscal sutures in the avascular zone are prone to a high failure rate. To enhance healing, augmented repair techniques like Arthroscopic Matrix-Based Meniscus Repair (AMMR) have been developed. This technique involves wrapping the sutured meniscus in a collagen membrane and injecting bone marrow into the lesion area. Although AMMR has shown promise in treating complex tears in the red-red and red-white zones, its effectiveness compared to traditional methods remains unclear due to a lack of comparative studies.
Purpose
This randomized controlled trial aims to compare the radiologic healing, patient-reported outcomes, and revision rates between the AMMR technique and classic meniscal suture (CMS) in treating meniscal tears within the avascular zone.
Methods
Between 2017 and 2022, patients with symptomatic meniscus tears affecting the central two-thirds of the meniscus (avascular zone) and extending over more than 1 cm were eligible. Exclusion criteria included partial meniscal tears, untreated ligament deficiency, cartilage damage > grade 2 (ICRS classification), mechanical axis deviation (varus/valgus) ≥ 2°, BMI ≥ 30, active smoking, and drug use. After diagnostic arthroscopy confirmed the suture feasibility, patients were randomly assigned to either the AMMR or CMS group. In the AMMR group, the suture was wrapped in a collagen membrane stabilized by sutures, followed with the injection under the membrane of 10 ml of bone marrow aspirated from the proximal tibial metaphysis and 2 ml of fibrin glue. Patient-reported outcome measures (PROMs), including KOOS, IKDC, and WOMET scores, were assessed for a minimum of two years postoperatively. A CT arthrogram was performed at two years and interpreted by a blinded radiologist. The incidence of revision surgeries was also recorded.
Results
A total of 96 patients were randomized: AMMR (n=47) and CMS (n=49). The mean age was 28±1.4 years, with a male-to-female ratio of 2.8 and a mean BMI of 24.1±3.7 kg/m². The medial meniscus was involved in 65% of cases. Tear patterns included longitudinal vertical (72%), radial (16%), complex (11%), and horizontal (1%) tears. The mean follow-up duration was 3.5±1.4 years. Ten patients were lost to follow-up at two years, five from each group. At the 2-year postoperative follow-up, CT arthrograms showed a significantly higher rate of complete non-healing in the CMS group (40.4%) compared to the AMMR group (20.4%) based on Henning’s criteria (p=0.03). Although revision surgery for partial meniscectomy was more common in the CMS group (13%) compared to the AMMR group (4%), the difference did not reach statistical significance (p=0.15). No significant differences in PROMs were observed between the groups at the final follow-up.
Conclusions
The AMMR technique demonstrates a higher radiological healing rate compared to conventional suture for meniscal tears in the avascular zone. This improved healing may contribute to a trend towards a reduced need for revision surgery, although further research is needed to confirm these findings.