Messner K, Gao J
Sports Medicine, Faculty of Health Sciences, Linköping University, Sweden.
J Anat. 1998 Aug;193 ( Pt 2)(Pt 2):161-78. doi: 10.1046/j.1469-7580.1998.19320161.x.
The menisci and their insertions into bone (entheses) represent a functional unit. Thanks to their firm entheses, the menisci are able to distribute loads and therefore reduce the stresses on the tibia, a function which is regarded essential for cartilage protection and prevention of osteoarthrosis. The tissue of the hypocellular meniscal body consists mainly of water and a dense elaborate type I collagen network with a predominantly circumferential alignment. The content of different collagens, proteoglycans and nonproteoglycan proteins shows significant regional variations probably reflecting functional adaptation. The meniscal horns are attached via meniscal insertional ligaments mainly to tibial bone. At the enthesis, the fibres of the insertional ligaments attach to bone via uncalcified and calcified fibrocartilages. This anatomical configuration of gradual transition from soft to hard tissue, which is identical to other ligament entheses, is certainly essential for normal mechanical function and probably protects this vulnerable transition between 2 biomechanically different tissues from failure. Clinical treatment of meniscal tears needs to be based on these special anatomical and functional characteristics. Partial meniscectomy will preserve some of the load distribution function of the meniscus only when the meniscal body enthesis entity is preserved. Repair of peripheral longitudinal tears will heal and probably preserve the load distribution function of the meniscus, whereas radial tears through the whole meniscal periphery or more central and complex tears may be induced to heal, but probably do not preserve the load distribution function. There is no proof that replacement of the meniscus with an allograft can reestablish some of the important meniscal functions, and thereby prevent or reduce the development of osteoarthrosis which is common after meniscectomy. After implantation, major problems are the remodelling of the graft to inferior structural, biochemical and mechanical properties and its insufficient fixation to bone which fails to duplicate a normal anatomical configuration and therefore a functional meniscal enthesis.
半月板及其在骨中的附着处（起止点）构成一个功能单元。由于其牢固的起止点，半月板能够分散负荷，从而减轻胫骨上的应力，这一功能被认为对保护软骨和预防骨关节炎至关重要。细胞成分较少的半月板体组织主要由水和密集精细的I型胶原网络组成，胶原纤维主要呈环向排列。不同胶原蛋白、蛋白聚糖和非蛋白聚糖蛋白的含量存在显著的区域差异，这可能反映了功能适应性。半月板角主要通过半月板插入韧带附着于胫骨。在起止点处，插入韧带的纤维通过未钙化和钙化的纤维软骨附着于骨。这种从软组织到硬组织的逐渐过渡的解剖结构，与其他韧带起止点相同，对于正常的力学功能肯定至关重要，并且可能保护这两种生物力学不同组织之间的脆弱过渡部位不发生破坏。半月板撕裂的临床治疗需要基于这些特殊的解剖和功能特征。仅当半月板体起止点实体得以保留时，部分半月板切除术才会保留半月板的一些负荷分布功能。周边纵向撕裂的修复能够愈合，并且可能保留半月板的负荷分布功能，而贯穿整个半月板周边的放射状撕裂或更靠近中央的复杂撕裂可能会愈合，但可能无法保留负荷分布功能。没有证据表明同种异体移植半月板能够重建半月板的一些重要功能，从而预防或减少半月板切除术后常见的骨关节炎的发生。植入后，主要问题是移植物会重塑为结构、生化和力学性能较差的组织，并且其与骨的固定不足，无法复制正常的解剖结构，因此也无法形成功能性的半月板起止点。
