Myelography for clinically atypical prolapsed lumbar intervertebral discs.

IN a significant number of cases of posterior prolapse of a lumbar intervertebral disc there is doubt as to the cause of symptoms and of the level affected. Contrast myelography is frequently used in this type of case in the hope that a more definite answer may be given. Reports on the accuracy of myelography in the diagnosis of prolapsed lumbar intervertebral disc vary between 67 per cent and 95 per cent (Scoville, Moretz and Hankins, 1948; Camp, 1939; Soderberg and Sjoberg, 1961), and as there is a wide variation between these figures it was decided to report the experience with myelography at the Orthopaedic Unit of Musgrave Park Hospital. In this unit myelography is not carried out routinely in all cases of suspected prolapsed lumbar disc. It is reserved for those which are not clinically typical, and in whom operation is contemplated when conservative treatment has failed.