Benjamin M, Qin S, Ralphs J R
School of Molecular and Medical Biosciences Anatomy Unit, University of Wales College of Cardiff, UK.
J Anat. 1995 Dec;187 ( Pt 3)(Pt 3):625-33.
The presence of fibrocartilage in tendons that wrap around bony or fibrous pulleys is well known. It is an adaptation to resisting compression or shear, but the extent to which the structure of most human tendons is modified where they contact pulleys is less clear, for there has been no single comprehensive survey of a large number of sites. Less is known of the structure of the corresponding pulleys. In the present study, 38 regions of tendons that wrap around bony pulleys or pass beneath fibrous retinacula have been studied in routine histology sections taken from each of 2 or 3 elderly dissecting room cadavers. Most of the corresponding pulleys have also been examined. Fibrocartilage was present in 22 of the 38 tendon sites and it was most conspicuous where the tendons pressed predominantly against bone rather than retinacula and where they showed a large change in direction. Fibrocartilage was more characteristic of tendons at the ankle than the wrist, probably because the long axis of the foot is at right angles to that of the leg. There was considerable variation in the structure of tendon fibrocartilage. The most fibrocartilaginous tendons had oval or round cells embedded in a highly metachromatic matrix with interwoven or spiralling collagen fibres. At other sites, fibrocartilage cells were arranged in rows between parallel collagen fibres. The differences probably relate to differences in development. A single tendon could be modified at successive points along its length and fibrocartilage could be present in the endotenon and epitenon as well as in the tendon itself. Pathological changes seen in 'wrap around' tendons were fragmentation and partial delamination of the compressed surface, chondrocyte clustering, fatty infiltration and bone formation. Three types of pulleys were described for tendons--bony prominences and grooves, fibrous retinacula and synovial joints. The extent of cartilaginous differentiation on the periosteum of bony pulleys frequently mirrored that in the corresponding tendon. The cartilage or fibrocartilage prevents the tendon from 'sawing' through the bone. Some of the best known retinacula were largely fibrous, though the inferior peroneal retinaculum and the trochlea for the superior oblique were cartilaginous. The results underline the considerable regional heterogeneity in different tendons and their pulleys. They show that one tendon is not like another and that tendons may need to be carefully selected for particular surgical transfers or joint reconstructions.
环绕骨或纤维滑车的肌腱中存在纤维软骨，这是众所周知的。这是一种适应抵抗压缩或剪切的结构，但大多数人类肌腱在与滑车接触处的结构改变程度尚不清楚，因为尚未对大量部位进行过全面的单一调查。对于相应滑车的结构了解更少。在本研究中，从2或3具老年解剖室尸体的常规组织学切片中，研究了38个环绕骨滑车或从纤维支持带下方穿过的肌腱区域。大多数相应的滑车也进行了检查。38个肌腱部位中有22个存在纤维软骨，在肌腱主要压在骨而非支持带上且方向变化较大的部位最为明显。与腕部相比，纤维软骨在踝部肌腱中更具特征性，可能是因为足部的长轴与腿部的长轴成直角。肌腱纤维软骨的结构存在相当大的差异。纤维软骨最多的肌腱中，椭圆形或圆形细胞嵌入高度异染的基质中，胶原纤维相互交织或呈螺旋状排列。在其他部位，纤维软骨细胞排列在平行胶原纤维之间。这些差异可能与发育差异有关。一条肌腱在其长度上的连续点可能会发生改变，纤维软骨可能存在于腱内膜、腱外膜以及肌腱本身。在“环绕”肌腱中观察到的病理变化包括压缩表面的碎裂和部分分层、软骨细胞聚集、脂肪浸润和骨形成。描述了三种类型的肌腱滑车——骨隆起和凹槽、纤维支持带和滑膜关节。骨滑车骨膜上软骨分化的程度常常与相应肌腱中的情况相似。软骨或纤维软骨可防止肌腱“锯”穿骨头。一些最知名的支持带主要是纤维性的，不过腓骨下支持带和上斜肌滑车是软骨性的。结果强调了不同肌腱及其滑车中存在相当大的区域异质性。它们表明一条肌腱与另一条不同，在进行特定的手术移位或关节重建时，可能需要仔细选择肌腱。
