A scanning electron microscopic and immunohistochemical study of spinal ligaments innervation

Neural elements in the interspinous and longitudinal ligaments of the human lumbar spine were investigated by means of scanning electron microscopy (SEM) and immunohistochemistry for neurofilament protein (NFP). The SEM results agree with our previous findings of nerve fibers and localized them in the superficial layers of the ligaments as well as in the deeper ligamentous substance. The immunohistochemical staining for NFP has clearly confirmed the presence of sensory nerve endings. Most of the nerve fibers terminated as simple free endings which are thought to be nociceptors.