For many years now percutaneous techniques have proved effective in the curative treatment of lumbar disc herniation, mostly in young subjects. This technique, however, is seldom indicated, let alone performed, in the cervical spine for a variety of reasons: a) the neck contains several closely arranged structures such as the vasculo-nervous bundles, the airway-digestive tract and the cervical spine around the spinal cord; b) the disc is approached by the anterior route, in contrast with the lumbo-sacral spine where the approach is posterolateral; c) the manufacturers insist on restrictions in the use of chymopapain in view of the potential risk of spinal cord damage, either by possible breaks in the meninges of by accidental diffusion of the enzyme into perimedullary epidural structures which support a particularly developed venous plexus; d) legal protection may be denied to operators who perform cervical chemonucleolysis, since the product has not yet been officially authorized, in France and perhaps elsewhere*, for treatment of cervical disc herniation. Several years of experience in the practice of cervical nucleolysis have convinced the authors that this method is remarkably effective and can be used in the treatment of cervicobrachial neuralgia (CBN) occurring in young subjects. Radiculalgia is essentially due to a disc fragment being positioned within the vertebral canal or a foramen, thereby compressing the nerve roots. During several years microsurgery of the disc has been effective in the treatment of refractory radiculalgia, and to compete with this procedure familiar to neurosurgeons cervical nucleolysis must convincingly demonstrate that its therapeutic value is at least as good as that of surgery. Finally, the vast majority of cervical disc herniations is made up of free disc fragments located within the meshes of the posterior longitudinal ligament of the spine (transligamentous fragment). Cervical nucleolysis was introduced in France by Bonafe and Lazorthes made enthusiastic by their first studies, and the idea of this procedure, developed by a radio-neurosurgical team, has gradually been gaining ground. The decision to intervene is made when the radiculalgia is recurrent or resistant to a well-conducted medical treatment of several weeks duration. Therefore all disc herniations that would have been treated surgically can be treated by injection of an enzyme. This point is very important, and in fact the well-codified and effective surgical procedure has progressively been abandoned by the operators, in view of the simplicity of nucleolysis and the rapid pain relief it procures.(ABSTRACT TRUNCATED AT 400 WORDS)