Langford L A, Schmidt R F
Anat Rec. 1983 May;206(1):71-8. doi: 10.1002/ar.1092060109.
The goal of this study is to determine the average numbers of afferent axons and postganglionic autonomic (sympathetic) efferent axons supplying the cat knee joint through the medial and posterior articular nerves. Interestingly, both nerves are composed primarily of unmyelinated axons. Only 20% of the axons in the medial articular nerve are myelinated, with the overwhelming majority, 80%, being unmyelinated. The posterior articular nerve has 78% unmyelinated and 22% myelinated axons. Neither nerve contains ventral root efferent axons. The sympathetic chain, in both nerves, contributes no myelinated and only 50% of the unmyelinated axons. The medial and posterior articular nerves are therefore predominantly afferent, since all myelinated and the remaining 50% of the unmyelinated axons arise from the dorsal root ganglion cell. The ratio of afferent unmyelinated to myelinated axons is 2:1. The roles of these afferent unmyelinated axons must now be considered in regard to joint kinesthetics and pain.
本研究的目的是确定通过内侧和后关节神经支配猫膝关节的传入轴突和节后自主（交感）传出轴突的平均数量。有趣的是，这两条神经主要由无髓鞘轴突组成。内侧关节神经中只有20%的轴突有髓鞘，绝大多数（80%）是无髓鞘的。后关节神经有78%的无髓鞘轴突和22%的有髓鞘轴突。两条神经均不包含腹根传出轴突。在这两条神经中，交感神经链均未提供有髓鞘轴突，仅提供50%的无髓鞘轴突。因此，内侧和后关节神经主要是传入性的，因为所有有髓鞘轴突和其余50%的无髓鞘轴突均来自背根神经节细胞。传入无髓鞘轴突与有髓鞘轴突的比例为2:1。现在必须从关节动觉和疼痛方面考虑这些传入无髓鞘轴突的作用。
