A longitudinal tear in the medial meniscal body decreased the in situ meniscus force under an axial load

Abstract

Purpose To clarify the effect of longitudinal tears of the medial meniscus on the in situ meniscus force and the tibiofemoral relationship under axial load. Methods Twenty-one intact porcine knees were mounted on a 6-degrees of freedom robotic system, and the force and threedimensional path of the knee joints were recorded during three cycles under a 250-N axial load at 30°, 60°, 90° and 120° of knee flexion. They were divided into three groups of seven knees with longitudinal tears in the middle to the posterior segment of the medial meniscus based on the tear site: rim, outer one-third and inner one-third of the meniscal body. After creating tears, the same tests were performed. Finally, all paths were reproduced after total medial meniscectomy, and the in situ force of the medial meniscus was calculated based on the principle of superposition. Results With a longitudinal tear, the in situ force of the medial meniscus was significantly decreased at 60°, 90° and 120° of knee flexion, regardless of the tear site. The decrement was greater with a tear in the meniscal body than a tear in the rim. A longitudinal tear in the meniscal body caused a significantly greater tibial varus rotation than a tear in the rim at all flexion angles. Conclusion Longitudinal tears significantly decreased the in situ force of the medial meniscus. Tears in the meniscal body caused a larger decrease of the in situ meniscus force and greater varus tibial rotation than tears in the rim.

Selective Extracellular Matrix Guided Mesenchymal Stem Cell Self‐Aggregate Engineering for Replication of Meniscal Zonal Tissue Gradient in a Porcine Meniscectomy Model

“…All samples were tested by compressing the joint with a 200 N axial load at two different flexion angles (30° and 60°), similar to the previously published protocol. [ 72,73 ] The peak medial contact pressure, the average medial contact pressure and the medial contact area were tested for each knee.…”

Reduction of in situ force through the meniscus with phased inner resection of medial meniscus: an experimental study in a porcine model

“…2a) [21]. A pilot study using five samples was conducted to evaluate the effect of the osteotomy on the in situ force of the meniscus as well as the tibiofemoral relationship under a 300-N axial load at 60°of knee flexion, and the osteotomy led to no significant change in these parameters like the previous study [15]. The results were shown in Table 1.…”

“…It could quantify/visualize the tibiofemoral contact pressure or contact area [11][12][13], although it cannot evaluate the meniscal functions directly, resulting in underestimation the role of the inner portion of the meniscus [12,13]. In situ force of the meniscus is a novel parameter to represent the resultant force through an injured meniscus [14,15]. In situ force measurement of the meniscus can be used to directly estimate the meniscal function such as a load transmission and to more sensitively assess the influence of inner resections of the medial meniscus on the tibiofemoral joint.…”

Meniscus tears treatment: The good, the bad and the ugly-patterns classification and practical guide

“…However, if the tear is more than 15 mm and involves the posterior horn of the meniscus, a significant change of knee biomechanics has been reported[ 47 ]. Moreover, longitudinal tears were found to decrease the in-situ meniscus force[ 48 ], thus potentially impacting on meniscus function. In addition to this, longitudinal tears of medial meniscus were significantly correlated with meniscus extrusion[ 49 ], especially if the tear size increases.…”