[Degenerative changes in intervertebral disks]

A histotopographic study of lumbar spine was made in 27 deceased of the age of 2 to 85 years lacking of any spinal clinical symptomatology. Regressive changes were found in all the intervertebral disks except in infants. A central necrosis was present in 26 cases and pericentral striped necrosis in 19 cases. Other disks showed consequences of necrosis--vascularization, scarring, regenerative proliferation of chondrocytes, ganglion type cavities. A concept of disk lesion as a trigger of further spinal lesions was supported by frequent regressive changes of the disks. Schmorl's (internal) nodes were found in 35 cases, quite often in young persons without clinical symptomatology. The amount of glycosaminoglycans during the disk regression was detected by Safranin O-Fast Green stain with ambiguous results. A hypothetical spontaneous vanishing of the nucleus pulposus in accordance with the age was a topic of discussion. Protrusions of the disks into the spinal canal were not found. Initial osteophytes at ventral margins of vertebral bodies were identified in 49 cases, at dorsal margins in only 3 cases.