[Syndrome of redundant nerve roots of the cauda equina. Apropos of 2 cases].

Redundant nerve roots of the cauda equina (RNR) are considered to be extremely rare. This finding was reported for the first time in 1953 by Verbiest and since then several articles have being published on this subject. In an extensive review of the literature we have found 60 cases of RNR, 54 cases of which were operated including two new cases that we report in the present article. The RNR consist of elongated, tortuous and serpiginous nerve roots of the cauda equina. This disorder mainly affects males and the clinical history ranges from few months to three decades. The illness often start by a low back pain or sciatica associated or not with weakness or parasthesia of the lower limbs. There is sometimes a medullar claudication with gait ant sphincters disturbances. The electromyogram shows signs of chronic denervation and there is a high protein level in the CSF exam. X-rays of the lumbosacral spine show spondylarthrosis generally associated with a narrow spinal canal. The diagnosis is made by a lumbar myelogram which shows a partial or complete block of the column contrast. Serpentine defects suggest an arteriovenous medullar malformation, but the aortic angiogram is normal. At the opening of the dura-mater there is a sudden extrusion of the roots which are under pressure. The elongated roots are generally knotten or curled. One or several roots are very long but their diameter and aspect are normal. The treatment includes a decompressive lumbar laminectomy associated with a decompressive duroplasty.(ABSTRACT TRUNCATED AT 250 WORDS)