Department of Orthopaedic Surgery, Universidade Federal de São Paulo, UNIFESP, São Paulo, Brazil.
Department of Orthopaedic Surgery, Hospital Israelita Albert Einstein, São Paulo, Brazil.
Knee Surg Sports Traumatol Arthrosc. 2021 Sep;29(9):3124-3132. doi: 10.1007/s00167-020-06363-0. Epub 2020 Nov 22.
The primary objective of this study is to evaluate the contact areas, contact pressures, and peak pressures in the medial compartment of the knee in six sequential testing conditions. The secondary objective is to establish how much the medial meniscus is able to extrude, secondary to soft tissue injury while keeping its roots intact.
Ten cadaveric knees were dissected and tested in six conditions: (1) intact meniscus, (2) 2 mm extrusion, (3) 3 mm extrusion, (4) 4 mm extrusion, (5) maximum extrusion, (6) capsular based meniscal repair. Knees were loaded with a 1000-N axial compressive force at 0°, 30°, 60°, and 90° for each condition. Medial compartment contact area, average contact pressure, and peak contact pressure data were recorded.
When compared to the intact state, there was no statistically significant difference in medial compartment contact area at 2 mm of extrusion or 3 mm of extrusion (n.s.). There was a statistically significant decrease in contact area compared to the intact state at 4 mm (p = 0.015) and maximum extrusion (p < 0.001). The repair state was able to improve medial compartment contact area, and there was no statistically significant difference between the repair and the intact states (n.s.). No significant differences were found in the average contact pressure between the repair, intact, or maximum extrusion conditions at any flexion angle (n.s.). No significant differences were found in the peak contact pressure between the repair, intact, or maximum extrusion conditions at any flexion angle (n.s.).
In this in vitro model, medial meniscus extrusion greater than 4 mm reduced medial compartment contact area, but meniscal extrusion did not significantly increase pressure in the medial compartment. Additionally, meniscal centralization was effective in restoring the medial tibiofemoral contact area to intact state when the meniscal extrusion was secondary to meniscotibial ligament injury. The diagnosis of meniscal extrusion may not necessarily involve meniscal root injury. Since it is known that meniscal extrusion greater than 3 or 4 mm has a biomechanical impact on tibiofemoral compartment contact area and pressures, specific treatments can be established. Centralization restored medial compartment contact area to the intact state.
本研究的主要目的是评估内侧间室的接触面积、接触压力和峰值压力在连续 6 种测试条件下的变化。次要目的是确定内侧半月板在保持其根部完整的情况下，因软组织损伤而发生多大幅度的挤出。
10 个尸体膝关节在 6 种条件下进行解剖和测试：（1）完整半月板，（2）挤出 2mm，（3）挤出 3mm，（4）挤出 4mm，（5）最大挤出，（6）基于囊的半月板修复。膝关节在每个条件下以 0°、30°、60°和 90°加载 1000N 的轴向压缩力。记录内侧间室接触面积、平均接触压力和峰值接触压力数据。
与完整状态相比，在挤出 2mm 或 3mm 时，内侧间室接触面积没有统计学差异（无显著性）。与完整状态相比，在挤出 4mm 时（p=0.015）和最大挤出时（p<0.001），接触面积有统计学显著下降。修复状态能够改善内侧间室接触面积，且与完整状态相比无统计学差异（无显著性）。在任何屈曲角度下，修复状态、完整状态或最大挤出状态下的平均接触压力均无统计学差异（无显著性）。在任何屈曲角度下，修复状态、完整状态或最大挤出状态下的峰值接触压力均无统计学差异（无显著性）。
在这个体外模型中，内侧半月板挤出超过 4mm 会减少内侧间室接触面积，但半月板挤出不会显著增加内侧间室的压力。此外，当半月板挤压是由于半月板胫侧韧带损伤引起时，半月板中央化可以有效地将内侧胫骨股骨接触面积恢复到完整状态。半月板挤出的诊断不一定涉及半月板根部损伤。由于已知半月板挤出超过 3 或 4mm 对胫骨股骨间室接触面积和压力有生物力学影响，因此可以确定具体的治疗方法。中央化将内侧间室接触面积恢复到完整状态。
