O'Leary S A, White J L, Hu J C, Athanasiou K A
Department of Biomedical Engineering, University of California, Davis, California, USA.
Department of Biomedical Engineering, University of California, Irvine, California, USA.
Equine Vet J. 2018 Nov;50(6):800-808. doi: 10.1111/evj.12845. Epub 2018 May 17.
The equine cervical facet joint is a site of significant pathology. Located bilaterally on the dorsal spine, these diarthrodial joints work in conjunction with the intervertebral disc to facilitate appropriate spinal motion. Despite the high prevalence of pathology in this joint, the facet joint is understudied and thus lacking in viable treatment options.
The goal of this study was to characterise equine facet joint cartilage and provide a comprehensive database describing the morphological, histological, biochemical and biomechanical properties of this tissue.
Descriptive cadaver studies.
A total of 132 facet joint surfaces were harvested from the cervical spines of six skeletally mature horses (11 surfaces per animal) for compiling biomechanical and biochemical properties of hyaline cartilage of the equine cervical facet joints. Gross morphometric measurements and histological staining were performed on facet joint cartilage. Creep indentation and uniaxial strain-to-failure testing were used to determine the biomechanical compressive and tensile properties. Biochemical assays included quantification of total collagen, sulfated glycosaminoglycan and DNA content.
The facet joint surfaces were ovoid in shape with a flat articular surface. Histological analyses highlighted structures akin to articular cartilage of other synovial joints. In general, biomechanical and biochemical properties did not differ significantly between the inferior and superior joint surfaces as well as among spinal levels. Interestingly, compressive and tensile properties of cervical facet articular cartilage were lower than those of articular cartilage from other previously characterised equine joints. Removal of the superficial zone reduced the tissue's tensile strength, suggesting that this zone is important for the tensile integrity of the tissue.
Facet surfaces were sampled at a single, central location and do not capture the potential topographic variation in cartilage properties.
This is the first study to report the properties of equine cervical facet joint cartilage and may serve as the foundation for the development of future tissue-engineered replacements as well as other treatment strategies.
马的颈椎小关节是重要的病变部位。这些双动关节位于脊柱背侧两侧，与椎间盘协同作用以促进适当的脊柱运动。尽管该关节病变的发生率很高，但对小关节的研究较少，因此缺乏可行的治疗选择。
本研究的目的是对马的小关节软骨进行表征，并提供一个全面的数据库，描述该组织的形态学、组织学、生物化学和生物力学特性。
描述性尸体研究。
从六匹骨骼成熟的马的颈椎中采集了总共132个小关节表面（每只动物11个表面），以汇编马颈椎小关节透明软骨的生物力学和生物化学特性。对小关节软骨进行大体形态测量和组织学染色。采用蠕变压痕和单轴拉伸至破坏试验来确定生物力学压缩和拉伸特性。生化分析包括总胶原蛋白、硫酸化糖胺聚糖和DNA含量的定量。
小关节表面呈椭圆形，关节面平坦。组织学分析突出了与其他滑膜关节的关节软骨相似的结构。一般来说，上下关节表面以及不同脊柱节段之间的生物力学和生物化学特性没有显著差异。有趣的是，颈椎小关节软骨的压缩和拉伸特性低于其他先前表征的马关节的关节软骨。去除表层会降低组织的拉伸强度，表明该区域对组织的拉伸完整性很重要。
小关节表面是在单个中心位置取样的，没有捕捉到软骨特性可能存在的地形变化。
这是第一项报告马颈椎小关节软骨特性的研究，可为未来组织工程替代物以及其他治疗策略的开发奠定基础。
