Clinical effect of medial meniscus posterior root repair combined with centralization technique in the treatment of medial meniscus posterior root tears

Purpose To investigate the clinical effect of medial meniscus posterior root repair combined with centralization technique in treating medial meniscus posterior root tears (MMPRTs). Methods A retrospective analysis was conducted on 87 patients with MMPRTs treated in the Department of Joint Surgery of Jinhua Central Hospital from January 2020 to May 2022. Thirty-four patients were males and 53 were females, with an overall average age of 56.4 +/- 5.9 years. Patients were divided into two groups based on different surgical methods: the conventional group (those who underwent simple medial meniscus root repair, n = 42) and the modified group (those who underwent medial meniscus root repair combined with centralization technique, n = 45). Clinical effects were evaluated before and after 2 years of surgery using the Lysholm and Knee Injury and Osteoarthritis Outcome Score (KOOS) scores. The inner meniscus displacement distance and the inner meniscus displacement ratio (medial meniscus extrusion (MME)) were compared before and after 2 years of surgery using magnetic resonance imaging. The degree of osteoarthritis (OA) and hip-knee-ankle (HKA) angle were compared before and after 2 years of surgery using X-ray films. OA degree was evaluated using the Kellgren-Lawrence (KL) grading system. Intergroup and intragroup comparisons were conducted. Results Baseline demographic data were comparable between the modified and conventional repair groups, with no statistically significant difference. All patients were followed up for 26.8 +/- 2.4 months postoperatively. After 2 years of follow-up, both groups exhibited significant improvement in Lysholm and KOOS scores compared with preoperative values (P = 0.049, P = 0.003 ), with the modified group showing significantly higher scores than the conventional repair group (P = 0.0001), and differences were statistically significant. In the conventional group, the lateral displacement of the medial meniscus reduced from 4.5 +/- 0.8 mm preoperatively to 4.0 +/- 0.5 mm at 2 years postoperatively (P = 0.528), and the MME ratio improved from 41.2 +/- 4.5% preoperatively to 39.3 +/- 3.9% postoperatively (P = 0.661). In the modified group, the lateral displacement of the medial meniscus reduced from 4.6 +/- 1 mm preoperatively to 2.6 +/- 0.7 mm at 2 years postoperatively (P = 0.0019), and the MME ratio improved from 42.0 +/- 5.2% preoperatively to 23.5 +/- 3.6% postoperatively (P < 0.0001). After 2 years of follow-up, the modified group exhibited a higher proportion of KL grades 0 and I, whereas the conventional group had a higher proportion of KL grades I and II, with statistically significant differences between the two groups (P = 0.019). No significant difference in the change in HKA between the two groups (P = 0.321, P = 0.401). Conclusion Both medial meniscus root repair and its combination with the centralization technique under arthroscopy can significantly enhance knee joint function and alleviate symptoms in patients with MMPRTs. Nevertheless, the combined technique can significantly reduce meniscus protrusion and delay the advancement of OA. Level of evidence Level III, retrospective observational study.