In 1927 and 1928 two patients with unusual cases of apparent extradural tumor of the spinal cord were operated on in University Hospital. The nodules which were removed were at first thought to be chondromas arising from intervertebral disks, but because microscopic examination showed no neoplastic tissue their nature and origin were for a time left in doubt. In the light of recent increase in knowledge concerning pathologic processes of the vertebral column, these nodules are now identified as herniations of nucleus pulposus tissue from intervertebral disks. Reports of these cases and a brief description of certain aspects of pathologic conditions of the disks follow.
REPORT OF CASES
—Syndrome of involvement of cauda equina. Complete cerebrospinal fluid block. Localization with iodized oil. Laminectomy. Removal of nodule from intervertebral disk. Recovery.
—F. R. H., salesman, aged 31, was referred by Dr. F. J. Graham in December 1926, complaining