Prolapsed intervertebral disc at the upper lumbar level. Diagnostic difficulties. A report on 12 cases.

Prolapsed intervertebral disc at the upper lumbar level causes problems in diagnosis. Compressive root syndromes at L1-L2-L3 present clinical features which are not very specific. They are frequently pluriradicular and may be referred to areas of atypical distribution. The anatomical features and the relationship between discs and nerve roots and any variations are illustrated. Based on our personal experience with 12 cases of herniation of the first two lumbar discs, we would emphasize the importance of extending myelography and CT scanning to the high lumbar metameres whenever the symptomatology is equivocal. If such a policy were adopted, the incidence of prolapsed disc at the higher lumbar levels would probably be found to be higher than is at present supposed.