Medial meniscus posterior root tears and partial meniscectomy significantly increase stress in the knee joint during dynamic gait

Abstract

Purpose As a simple and invasive treatment, arthroscopic medial meniscal posterior horn resections (MMPHRs) can relieve the obstructive symptoms of medial meniscus posterior root tears (MMPRTs) but with the risk of aggravating biomechanical changes of the joint. The aim of this study was to analyze dynamic simulation of the knee joint after medial meniscus posterior root tear and posterior horn resection. Methods This study established static and dynamic models of MMPRTs and MMPHRs on the basis of the intact medial meniscus model (IMM). In the inite element analysis, the three models were subjected to 1000 N axial static load and the human walking gait load deined by the ISO14243-1 standard to evaluate the inluence of MMPRTs and MMPHRs on knee joint mechanics during static standing and dynamic walking. Results In the static state, the load ratio of the medial and lateral compartments remained nearly constant (2:1), while in the dynamic state, the load ratio varied with the gait cycle. After MMPHRs, at 30% of the gait cycle, compared with the MMPRTs condition, the maximum von Mises stress of the lateral meniscus (LM) and the lateral tibial cartilage (LTC) were increased by 166.0% and 50.0%, respectively, while they changed by less than 5% during static analysis. The maximum von Mises stress of the medial meniscus (MM) decreased by 55.7%, and that of the medial femoral cartilage (MFC) increased by 53.5%. Conclusion After MMPHRs, compared with MMPRTs, there was no signiicant stress increase in articular cartilage in static analysis, but there was a stress increase and concentration in both medial and lateral compartments in dynamic analysis, which may aggravate joint degeneration. Therefore, in clinical treatments, restoring the natural structure of MMPRTs is irst recommended, especially for physically active patients. Keywords Meniscus root tear • Meniscectomy • Finite element analysis • Walking gait • Dynamic mechanical analysisQiang Yang, Xiao-yu Zhu and Jia-yi Bao contributed equally to this study and are co-irst authors.

Medial Meniscus Posterior Root Tear: How Far Have We Come and What Remains?

“…In addition, arthritic changes in the knee after partial meniscectomy for MMRTs have been reported to be more severe than those after non-operative treatment and surgical repair [ 58 , 63 , 64 ]. According to a recent study by Yang et al, meniscectomy for MMRTs results in a more significant stress concentration in the tibial cartilage compared with that in untreated MMRTs under dynamic loading conditions [ 65 ]. Therefore, owing to its limited clinical benefit, meniscectomy should be performed cautiously in selective cases [ 29 ].…”

Correlation between articular cartilage status on outcomes and survivorship following meniscal allograft transplantation: A systematic review

“…While meniscal repair is advocated in young patients and patients with tears in which the potential for meniscal healing is high, certain meniscal tear patterns, namely degenerative tears, are often irreparable and warrant partial, subtotal, or total meniscectomy [4]. In patients undergoing meniscectomy, loss of the meniscus effectively impairs load distribution in the tibiofemoral joint through loss of hoop stresses, altering contact mechanics with increased intracompartmental contact pressures, increasing the risk of early osteoarthritis development and progression [5,21,26,47]. In the setting of functional meniscal deficiency, especially young, active patients experiencing pain and limitations, meniscal allograft transplantation (MAT) has been shown to reduce pain and improve function [24,40,44,48].…”

The Effect of Lower Limb Alignment on Tibiofemoral Joint Contact Biomechanics after Medial Meniscus Posterior Root Repair: A Finite-Element Analysis

“…1 The anterior and posterior roots of the meniscus are firmly attached to the tibial plateau to maintain the position of the meniscus and prevent its displacement. 2 Bony or soft-tissue avulsion injuries, or complete radial tears within 10 mm of these attachments, are known as meniscal root tears. 3 Root tears result in a loss of resistance to hoop stresses in a manner functionally equivalent to total meniscectomy.…”