Corbo Gillian, Norris Madeleine, Getgood Alan, Burkhart Timothy A
Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada.
Fowler Kennedy Sport Medicine Clinic, 3M Centre, Western University, London, ON, Canada.
Knee Surg Sports Traumatol Arthrosc. 2017 Apr;25(4):1078-1085. doi: 10.1007/s00167-017-4424-y. Epub 2017 Jan 25.
The purpose of the current investigation was to characterize biomechanical differences between the supra- and infra-meniscal sections of the anterolateral ligament (ALL). We hypothesized that the supra-meniscal fibers of the ALL would be stronger and stiffer than the infra-meniscal fiber.
Nine cadaveric knee specimens [mean (SD) age = 79 (14.6) years] were dissected to identify the borders of the ALL while maintaining the anatomy of the lateral meniscus. The specimens were randomly assigned to either a supra-meniscal (the ALL below the meniscus was sectioned leaving only the supra-meniscal ALL intact) or an infra-meniscal (the ALL above the meniscus was sectioned leaving only the infra-meniscal attachment intact) group. The specimens were potted into dental cement such that the ALL was pulling laterally on the meniscus when the specimens were secured within an Instron materials testing machine. The specimens were subjected to a tensile failure test at 1 mm/s. The load at failure and stiffness were calculated from the force-displacement curves, while peak stress was calculated by normalizing the peak force to the cross-sectional area of the ALL. Furthermore, one intact knee specimen was used to perform a histological analysis on the two ALL sections using Masson's Trichome staining.
The infra-meniscal ALL had a significantly (p = 0.03) higher load to failure (195.0 vs. 132.1 N) and was significantly (p = 0.03) stiffer than the supra-meniscal fibers (24.8 vs. 12.3 N/mm). The relatively similar cross-section areas also resulted in the infra-meniscal sections having a greater peak stress (p = 0.04) (11.1 vs. 5.4 MPa). Histological analysis showed relatively consistent fiber orientation with similar organization noted throughout the fibers.
The ALL-meniscal construct that includes the infra-meniscal fibers was significantly stronger and stiffer than the construct that includes the supra-meniscal fibers. The infra-meniscal ALL is another important component of the anterolateral complex of the knee, and should be considered when presented with an ACL and/or meniscal injury.
本研究的目的是描述前外侧韧带（ALL）半月板上部分和半月板下部分之间的生物力学差异。我们假设ALL的半月板上纤维比半月板下纤维更强壮、更硬。
解剖9个尸体膝关节标本[平均（标准差）年龄 = 79（14.6）岁]，以确定ALL的边界，同时保持外侧半月板的解剖结构。将标本随机分为半月板上组（半月板下方的ALL被切断，仅保留半月板上ALL完整）或半月板下组（半月板上方的ALL被切断，仅保留半月板下附着部分完整）。将标本固定在牙科水泥中，以便当标本固定在Instron材料试验机内时，ALL向外侧牵拉半月板。标本以1 mm/s的速度进行拉伸破坏试验。根据力-位移曲线计算破坏载荷和刚度，而峰值应力通过将峰值力归一化到ALL的横截面积来计算。此外，使用一个完整的膝关节标本对ALL的两个部分进行Masson三色染色组织学分析。
半月板下ALL的破坏载荷显著更高（p = 0.03）（195.0对132.1 N），并且比半月板上纤维显著更硬（p = 0.03）（24.8对12.3 N/mm）。相对相似的横截面积也导致半月板下部分具有更大的峰值应力（p = 0.04）（11.1对5.4 MPa）。组织学分析显示纤维取向相对一致，整个纤维的组织结构相似。
包含半月板下纤维的ALL-半月板结构比包含半月板上纤维的结构显著更强壮、更硬。半月板下ALL是膝关节前外侧复合体的另一个重要组成部分，在出现前交叉韧带和/或半月板损伤时应予以考虑。
