[Lumbar post-laminectomy syndrome: II. Pain management using neuro-modulation techniques]. / Sindrome postlaminectomía lumbar II. Tratamiento del dolor mediante técnicas deneuromodulación.

The application of neuro-modulation techniques in general is currently gaining acceptance in various aspects of medicine. Neuro-modulation is defined as: "Therapeutical interventions using implantable devices to modify the functioning of central, peripheral and autonomic nervous systems". Following lumbar disc surgery, or lumbar spine surgery in general, several chronic pain syndromes can result, either in the lumbar region and/or in the lower limbs. The current status is for the application of surgery to the degenerative spine (degenerative disc disease and lumbar stenosis) for the relief of chronic pain. A review of the methodology of evidence based medicine, show that the instrumented and fusion techniques are not the answered despite 20 years of the use of these techniques following failure of surgery for the relief of back pain syndrome. Neuro-modulation techniques represent a step in the right direction for the management of these chronic pain syndromes. Frequently they enable the resolution of chronic pain following spine surgery without having to resort to repeat surgery. We describe here the different neuro-modulation techniques (spinal cord stimulation, spinal drug infusions) which can be used in the case of back surgery failure, and we describe technical aspects and "tricks of the trade" for the correct implantation of the devices used in techniques. Neuro-modulation techniques are applied to the management of chronic pain following disc surgery and represent a valid alternative to repeat surgery and/or arthrodesis (instrumented or not). Neurosurgeons are again called to play active roles in the field of neuro-modulation for the treatment.

[Surgical neuromodulation: new frontiers in neurosurgery]. / Neuromodulación quirúrgica. Nuevos horizontes en Neurocirugía.

OBJECTIVES: Surgical neuromodulation refers to all those techniques that use implantable devices that discharge electricity or chemical substances that modify nerve signal transmission in order to achieve inhibition, excitation or modulation of the activity of neuronal groups and networks, and to achieve a therapeutic effect. Neuromodulation encompasses different scientific aspects and technologies which need to be defined. MATERIAL AND METHOD: From the surgical point of view, neuromodulation is defined as: those intervention techniques that alter the transmission of neuronal signals using implantable electrical or chemical devices with the objective of stimulating, inhibiting or modulating the activity of neurones or neuronal networks to achieve therapeutic effects. A clinical definition makes reference to the use of reversible electrical or chemical stimulation of the nervous system to manipulate its activity in order to treat some specific types of chronic pain and conditions such as spasticity, epilepsy, cardiac ischemia, alterations in the motility of the intestine and of the bladder, lesions of the nervous system, and alterations in mobility, visual, auditory or psychiatric status. Neurosurgeons have been well trained to perform a great number of surgical techniques of neuromodulation, even including helping to significantly increase biomedical activities and the application of high technology to the central and peripheral nervous system. CONCLUSIONS: Surgical neuromodulation encourages the neurosurgeon to go also away from the classical techniques of surgical resection and neuroablative procedures, and to enter into the new field of neuroengineering to re-establish lost neurological functions. The inter-relationship between the brain and the computer (brain-machine interface) has already occurred and has been applied in the field of neuroprosthetics and deep brain stimulation. For neurosurgery in general and for Spain in particular, this represents a new opportunity to embark on a high technology path that would involve years of research but, applying these new, non-invasive surgical techniques would help resolve the neurological problems of many of our patients.

[Controversies about instrumented surgery and pain relief in degenerative lumbar spine pain. Results of scientific evidence]. / Controversias de la cirugía instrumentada y el tratamiento del dolor lumbar por enfermedad degenerativa. Resultados de la evidencia científica.

Investigation and development of new techniques for intrumented surgery of the spine is not free of conflicts of interest. The influence of financial forces in the development of new technologies an its immediately application to spine surgery, shows the relationship between the published results and the industry support. Even authors who have defend eagerly fusion techniques, it have been demonstrated that them are very much involved in the revision of new articles to be published and in the approval process of new spinal technologies. When we analyze the published results of spine surgery, we must bear in mind what have been call in the "American Stock and Exchange" as "the bubble of spine surgery". The scientific literature doesn't show clear evidence in the cost-benefit studies of most instrumented surgical interventions of the spine compare with the conservative treatments. It has not been yet demonstrated that fusion surgery and disc replacement are better options than the conservative treatment. It's necessary to point out that at present "there are relationships between the industry and back pain, and there is also an industry of the back pain". Nonetheless, the "market of the spine surgery" is growing up because patients are demanding solutions for their back problems. The tide of scientific evidence seams to go against the spinal fusions in the degenerative disc disease, discogenic pain and inespecific back pain. After decades of advances in this field, the results of spinal fusions are mediocre. New epidemiological studies show that "spinal fusion must be accepted as a non proved or experimental method for the treatment of back pain". The surgical literature on spinal fusion published in the last 20 years following the Cochrane's method establish that: 1- this is at least incomplete, not reliable and careless; 2- the instrumentation seems to slightly increase the fusion rate; 3- the instrumentation doesn't improve the clinical results in general, lacking studies in subgroups of patients. We still are needing randomized studies to compare the surgical results with the natural history of the disease, the placebo effect, or the conservative treatment. The European Guidelines for lumbar chronic pain management show a "strong evidence" indicating that complex and demanding spine surgery where different instrumentation is used, is not more effective than a simple, safer and cheaper posterolateral fusion without instrumentation. Recently, the literature published in this field is sending a message to use "minimally invasive techniques", abandon transpedicular fusions and clearly indicating that we must apply the knowledge accumulated at least along the last 20 years based on the scientific evidence. In conclusion, based in recent information, we must recommend the "abandon of the instrumented pathway" in a great number of present indications for degenerative spine surgery, and look for new strategies in the field of rehabilitation and conservative treatments correctly apply, using before the decompressive and instrumented surgery all the interventional and minimally invasive techniques that are presently offer in the field of modem lumbar chronic pain treatment.

[Lumbar post-laminectomy syndrome I. Pain management using interventionist techniques]. / Síndrome postlaminectomía lumbar I. Tratamiento del dolor mediante técnicas intervencionistas.

Chronic low back pain and ciatica after surgery is one of the main reasons for referring patients to multidisciplinary pain units (MPU). The future expansions of MPU have promted neurosurgeons in Spain to re-enter the field of chronic pain management and to recover their enthusiam, that have been lost severel years ago for various reasons. We do not intend dealing with the new instrumented surgical options for the post-laminectoy pain, but rather into the indications and descriptions of the interventional techniques for lumbar and sciatic pain managemet. Currently there are a great number of percutaneous techniques to achieve pain control in the post-laminectomy syndrome. Traditional neuroablative techniques at the spinal cord or the cerebral levels are not any longer indicated. Nonetheless, lumbar sympathectomy and thermo-neurolisis either with chilling or heating, are back in favour, due to the development of new devices and applications. Neuromodulation techniques which are also applicable to this pathology will be the subjet of another article. Pulsed radio-frecuency apperars to favour the safe application of electricity to the dorsal root ganglion or to the root itself thus avoiding the fear of permanent root and/or ganglion thermal lesions that frecuently occurred with the older techniques. Several strategies for pain relief are described, step by step and real figures are depicted in order to make the procedures more understandable and for the easier transmission of knowledge.