Twenty-nine fragments from hemlated lumbar discs of patients over 60 years of age were studied pathohlstologlcally. For comparison, 109 discs from patients under 59 years of age also were observed. They were classified into seven types according to their composition. In 70percnt; of discs from patients between 60 and 69 and In 80percnt; of discs from patients over 70, the fragments were composed of the anulus fibrosus and the cartilaginous end-plate. The authors concluded that the cartilaginous end-plate had avulsed from the vertebral body and hernlated with the anulus fibrosus in these cases. This type of herniation occurs more often than herniation of the nucleus pulposus over 30, and may be most common in elderly patients because of their advanced disc degeneration.
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