[Chronic sciatalgia caused by sensitive deafferentiation following surgery for lumbar disk hernia: clinical and therapeutic aspects. Apropos of 110 patients].

Sensitive deafferentation is a well recognized entity which has changed the therapeutic approach of some kinds of chronic post operative sciatalgia. It mainly occurs related with a long story of radicular pain and the responsibility of so-called epidural fibrosis has to be discussed. The case records of 110 consecutive patients with deafferentation sciatalgia were reviewed and the clinical data precised: chronic and lasting burning pain with acute nightly paroxysms and sensitive alterations at objective examination. Neuroradiological explorations eliminated the possibility of recurrent disc herniation and neurophysiological tests assessed the chronic radicular suffering and the degree of lemniscal degeneration. After medical treatment (analgesic drugs with central tropism), a strict clinical assessment of pain intensity allowed optimal choice of the technique of neurostimulation: transcutaneous electrical stimulation (51 patients) and/or spinal cord stimulation (59 patients). The efficacy of transcutaneous stimulation (40 excellent and good results) was most often related to its continuous utilisation with a short post-effect. Its side-effects and the frequency of multiradicular involvement lead to spinal cord stimulation. With a mean follow-up period of 37 months, the pain relief was considered as excellent in 51.5%, good in 38% and poor in 8.5% of the patients. One patient had a negative test and was not definitively implanted. Another case failed to respond to stimulation. The clinical and technical complication of the method are reported.