Fischenich Kristine M, Lewis Jackson, Kindsfater Kirk A, Bailey Travis S, Haut Donahue Tammy L
School of Biomedical Engineering, Colorado State University, Fort Collins, CO, USA.
Orthopedic Center of the Rockies, Fort Collins, CO, USA.
J Biomech. 2015 Jun 1;48(8):1407-11. doi: 10.1016/j.jbiomech.2015.02.042. Epub 2015 Feb 26.
Healthy menisci function within the joint to prevent the underlying articular cartilage from excessive loads. Understanding how mechanical properties of menisci change with degeneration can drive future therapeutic studies to prevent this degeneration. Thus, the goal of this study was to characterize both compressive and tensile moduli of human menisci with varying degrees of gross damage due to osteoarthritis (OA). Twenty four paired menisci were collected from total knee joint replacement patients and the menisci were graded on a scale from 0-4 according to level of gross meniscal degeneration with 0=normal and 4=full tissue maceration. Each meniscus was then sectioned into anterior and posterior regions and subjected to indentation relaxation tests. Samples were sliced into 1mm thick strips, made into dumbbells using a custom punch, and pulled to failure. Significant decreases in instantaneous compressive modulus were seen in the lateral posterior region between grades 0 and 1 (36% decrease) and in the medial anterior regions between grades 1 and 2 (67% decrease) and 1 and 3 (72% decrease). Changes in equilibrium modulus where seen in the lateral anterior region between grades 1 and 2 (35% decrease), lateral posterior region between grades 0-2 (41% decrease), and medial anterior regions between grades 1 and 2 (59% decrease), 1 and 3 (67% decrease), 2 and 4 (54% decrease), and 3 and 4 (42% decrease). No significant changes were observed in tensile modulus across all regions and degenerative grades. The results of this study demonstrate the compressive moduli are affected even in early stages of gross degeneration, and continue to decrease with increased deterioration. However, osteoarthritic menisci retain a tensile modulus similar to that of previously reported healthy menisci. This study highlights progressive changes in meniscal mechanical compressive integrity as level of gross tissue degradation increases, and thus, early interventions should focus on restoring or preserving compressive integrity.
健康的半月板在关节内发挥作用，防止下方的关节软骨承受过大负荷。了解半月板的力学性能如何随退变而变化，可为未来预防这种退变的治疗研究提供指导。因此，本研究的目的是表征因骨关节炎（OA）而具有不同程度大体损伤的人类半月板的压缩模量和拉伸模量。从全膝关节置换患者中收集了24对半月板，并根据半月板大体退变程度在0-4级范围内进行分级，0级为正常，4级为组织完全浸软。然后将每个半月板切成前后区域，并进行压痕松弛试验。将样本切成1毫米厚的条带，使用定制冲头制成哑铃状，然后拉伸至断裂。在0级和1级之间的外侧后区域（降低36%）、1级和2级之间以及1级和3级之间的内侧前区域（分别降低67%和72%）观察到瞬时压缩模量显著降低。在1级和2级之间的外侧前区域（降低35%）、0-2级之间的外侧后区域（降低41%）以及1级和2级之间、1级和3级之间、2级和4级之间以及3级和4级之间的内侧前区域（分别降低59%、67%、54%和42%）观察到平衡模量的变化。在所有区域和退变等级中，拉伸模量均未观察到显著变化。本研究结果表明，即使在大体退变的早期阶段，压缩模量也会受到影响，并随着退变程度的增加而持续降低。然而，骨关节炎半月板的拉伸模量与先前报道的健康半月板相似。本研究强调了随着组织大体降解程度的增加，半月板力学压缩完整性的渐进性变化，因此，早期干预应侧重于恢复或保持压缩完整性。
