Comparison of the clinical outcomes of transtibial pull-out repair for medial meniscus posterior root tear: Two simple stitches versus modified Mason-Allen suture

Background: Transtibial pullout repair of a medial meniscus posterior root tear (MMPRT) is a commonly used procedure, and several techniques have been reported. We hypothesised that pull-out repairs using two simple stitches (TSS) would have similar postoperative outcomes as those using the modified Mason-Allen suture with FasT-Fix (F-MMA). We aimed to investigate the clinical outcomes of these techniques, including the meniscal healing status and osteoarthritic change. Methods: The data of 68 patients who underwent transtibial pull-out repair were retrospectively investigated. The patients were divided into two groups of 41 and 27 patients using F-MMA and TSS, respectively. The clinical outcomes were assessed preoperatively and at second-look arthroscopy (the mean period from surgery was one year) using the Knee injury and Osteoarthritis Outcome Score. The meniscal healing status, evaluated at second-look arthroscopy, was compared between the two groups. The cartilage damage was graded as per the classification of the International Cartilage Repair Society and compared at the primary surgery and second-look arthroscopy. Results: Both groups showed significant improvement in each clinical score. No significant difference was seen in the clinical outcome scores and the meniscal healing status between the two groups at second-look arthroscopy. Moreover, no significant progression of cartilage damage was observed in both groups. Fourteen patients in the F-MMA group developed a complication of suture bar failures postoperatively; however, there were no complications in the TSS group. Conclusions: The TSS and F-MMA techniques showed favourable clinical outcomes and would be established as clinically useful techniques for the MMPRT treatment.