Central sympathetic mechanisms of blood pressure control in hamsters

The goal of this study was to investigate central vasomotor control of blood pressure in golden hamsters. Electrophysiological experiments demonstrated that tonic and reflex firing of renal nerves was controlled by brainstem and spinal circuits in manner similar to control of these nerves in rats, rabbits and cats. These findings confirmed that autonomic neural circuits for vasomotor control in hamsters are functionally similar to those of other well-studied species.

[Carbon dioxide laser posterior ventriculocordectomy for treatment of bilateral vocal cord abductor paralysis]

Several surgical procedures have been proposed for the treatment of bilateral vocal cord abductor paralysis. All, whether conventional or microsurgical, are designed to achieve a compromise between phonation and respiration that ensures, however, good voice quality. In this study we present and discuss our preliminary results with C02 laser posterior ventriculocordectomy (PVC). This microsurgical procedure stems from the work of Chevalier-Jackson and extends the range of application of modern posterior cordectomy. Chevalier-Jackson's original idea (ventriculocordectomy) has been developed and integrated in the light of the most recent data on C02 laser posterior cordectomy. At our Institute, we have employed this technique in treating 13 patients with bilateral vocal cord abductor paralysis. The age range of these patients, 9 females and 4 males, was 33-80 years. The etiology varied: iatrogenic post-thyroidectomy in 8 cases, post-traumatic in 2, secondary to a central lesion in 3. In 3 patients a tracheostomy tube was in place upon hospitalization. Deglutition, even for fluids, was usually promptly recovered. Resting and external dyspnea improved in all those patients who had not been previously tracheotomized. It was possible to remove the tracheotomy the in two out of three cases. We found no evidence of iatrogenic glottic stenosis among our cases. In our experience, endoscopic laser posterior ventriculo-cordectomy has many advantages: the maneuvers are rapid, simple, straightforward and easy to perform; the operation is reliable and ensures adequate airway patency and freedom from dyspnea during daily activity. The risk of complications, such as granuloma or cicatricial stenosis, is low as as long as appropriate steps are taken before and during the operation.

Intrathecal excitatory amino acid (EAA) agonists increase tail flick latencies (TFLs) of spinal rats

The facilitation of spinal nociceptive reflexes that occurs after spinal transection reveals the existence of descending, supraspinally mediated inhibition. Substantial evidence indicates that the excitatory amino acids (EAAs) are involved in these spinal circuits. Therefore, it was hypothesized that reflex facilitation in the spinal animal might be due to the removal of inhibitory input normally exerted on the spinal action of EAAs. If so, the facilitatory decrease in reflex latency, observed in the spinal preparation, might be potentiated by intrathecal (IT) administration of EAA agonists. This was tested by comparing the effect of IT injections of N-methyl-D-aspartate (NMDA) and alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA) on the thermally elicited tail flick (TF) response of Intact and acute spinal rats. In intact rats, a low (0.25 nM) dose of NMDA produced a hyperalgesic decrease in latency, relative to saline, whereas higher doses produced an overall increase in latency. A large dose (0.5 microM) produced overt signs of toxicity (crippling, self-mutilation, and loss of the reflex). Only the highest (1.0 nM) dose of AMPA affected the response, resulting in a significant increase. After spinal transection, the hyperalgesic reaction to 0.25 nM of NMDA was absent, and latencies were significantly increased by 1.0 nM. The toxic reaction to 0.5 microM appeared to be potentiated. Tail flick responses to AMPA were also significantly increased in spinal rats. Contrary to the prediction, reflex latencies were significantly increased by these drugs after spinal transection. It was suggested that, although the spinal action of EAAs appears to be supraspinally modulated, this influence may be facilitatory rather than inhibitory.

Subcutaneous formalin produces centrifugal hyperalgesia at a non-injected site via the NMDA-nitric oxide cascade

Previous work has demonstrated that pain facilitation can occur following injection of subcutaneous irritants, such as formalin. Such studies have focused on apparent pain facilitation induced at the site of irritant injection. Changes in processing of incoming pain information have typically been assumed to result from activation of neurocircuitry intrinsic to the spinal cord. The present series of studies have examined hyperalgesia exhibited at a site distant from the site of irritant injection and have begun to define the neurocircuitry and neuropharmacology underlying this pain enhancement. This work demonstrates that s.c. formalin injected into the dorsum of one hindpaw in rats produces prolonged hyperalgesia as measured by the tailflick test. Hyperalgesia is not mediated solely by circuitry intrinsic to the spinal cord, but rather involves activation of centrifugal pathways originating within the brain and descending to the spinal cord via pathway(s) outside of the dorsolateral funiculus. At the level of the spinal cord, this hyperalgesic state is mediated by an NMDA-nitric oxide cascade, since hyperalgesia can be abolished by administration of either an NMDA antagonist (APV) or a nitric oxide synthesis inhibitor (L-NAME).

Excitatory amino acid receptors in the rostral ventrolateral medulla mediate hypertension induced by carotid body chemoreceptor stimulation

The rostral ventrolateral medulla (RVLM) is involved in the mediation of cardiovascular responses to peripheral chemoreceptor stimulation. To investigate whether excitatory amino acid inputs in the RVLM are related to the responses to chemoreceptor stimulation, we microinjected kynurenate, an amino acid antagonist, unilaterally into the RVLM and examined its effects on the pressor response to stimulation of carotid body chemoreceptors. Male Wistar rats were anesthetized with urethane, paralyzed and artificially ventilated. The carotid chemoreceptors were stimulated with isotonic solutions of inorganic phosphate solution. Stimulation of carotid body chemoreceptors produced increases in blood pressure. Kynurenate injected ipsilaterally but not contralaterally into the RVLM markedly inhibited the pressor response to chemoreceptor stimulation. In rats with spinal transection, stimulation of carotid body chemoreceptors also produced increases in blood pressure. The pressor response in rats with spinal transection was inhibited by intravenous injection of a vasopressin antagonist or by kynurenate injected ipsilaterally into the RVLM. Kynurenate injected into the RVLM inhibited the pressor response to NMDA, AMPA and kainate but not to acetylcholine in intact rats. These findings indicate that excitatory amino acid receptors are involved in mediating the pressor response to carotid body chemoreceptor stimulation in the rat RVLM. It appears that the chemoreceptor stimulation produces an increase in vasopressin release and the enhancement of vasopressin release is also mediated by an increase in excitatory amino acid inputs in the RVLM.

[Vocal function after cordectomy (traditional surgical treatment vs CO2 laser): a comparative objective-instrumental evaluation]

Concerning the wider use of the CO2 laser in the treatment of laryngeal diseases, the Authors, in a comparative study based on an objective-instrumental evaluation, evaluated residual vocal function after traditional surgical treatment (chordectomy) vs. CO2 laser treatment. Forty-one patients treated for T1a glottic carcinoma (U.I.C.C. 1987) in last 8 years were examined Vocal function following CO2 laser surgery was evaluated in 17 patients (16 males and 1 female, aged between 38 and 78, with an average age of 53) and compared to vocal function of 24 patients treated with traditional chordectomy (23 males and 1 female, aged between 51 and 73, with an average age of 58). All patients showed a minimum follow-up of 30 months and none, at the time of evaluation, had undergone phonatory re-education. Glottic functionality evaluation was performed as follows: Evaluation of anatomical and functional results by means of a rigid fiberoptic laryngoscopy and subsequent photographic documentation for successive comparative evaluation. Evaluation of residual voice quality by phoniatricians otorhinolaryngologists and the patients themselves. Recording and electroacoustic analysis of some vocal samples. Laryngeal objectivity of surgical results were constantly related to subjective and instrumental voice evaluation. Phonatory results in patients treated with CO2 laser were better than those found in patients treated with traditional chordectomy.

Treatment of cancer-related pain: when orally administered medications fail

OBJECTIVE

To summarize the available pain-relieving interventions other than oral medications for cancer-related pain.

DESIGN

The pertinent literature is reviewed, and the various options for treating pain in patients with cancer are discussed.

MATERIAL AND METHODS

The appropriate situations for use of parenteral administration of opioids, spinal analgesia, neural blockade, and neurosurgical treatment are outlined, and the potential problems and complications associated with these techniques are described.

RESULTS

The basic approach to the management of pain in patients with cancer is to begin treatment with less potent analgesic agents early and to progress toward use of more potent pharmaceutical agents, adjuvant drugs, and invasive procedures as needed for alleviation of pain. With parenteral administration of opioids, the dosage can be adjusted rapidly, and therapy can be continued even though a patient may have gastrointestinal dysfunction. A portable ambulatory infusion pump can be used in selected patients. The major advantage of spinal opioid analgesia is the intense analgesia provided with minimal side effects. The potential complications and the availability of treatment alternatives have limited the use of neurolytic blocks, which usually provide only temporary relief of pain. In carefully selected patients with pancreatic or other upper gastrointestinal neoplasms, however, neurolytic celiac plexus and splanchnic nerve blocks are effective. Patients who fail to respond to conservative interventions may be candidates for neurosurgical procedures, such as spinal cord, cortical, or brain-stem stimulation or neuroablative operations (most commonly, cordotomy).

CONCLUSION

Cancer-related pain continues to be a major problem, and clinicians should be aware of the availability of effective treatment strategies and techniques. When orally administered medications fail to control pain or cause excessive side effects, patients should be referred to an appropriate specialist or medical center for consideration of other pain-relieving techniques.

Evidence of a role for N-methyl-D-aspartate (NMDA) receptors in the facilitation of tail withdrawal after spinal transection

Peripheral injury produces a characteristic excitation of spinal cord dorsal horn cells (wind-up) which is associated with a facilitation of spinal nociceptive reflexes (hyperalgesia). These phenomena are believed to be mediated by a trauma-induced increase in the release of excitatory amino acids (EAAs). A similar increase in the activity of dorsal horn neurons and spinal reflexes occurs after spinal transection. Therefore, the present studies examined the possibility that EAAs, acting through the NMDA receptor, might also be involved in behavioral hyperalgesia produced by central injury. The first experiment assessed the effect of pretreatment with the NMDA antagonist, ketamine, on the facilitated tail flick (TF) response of spinally transected rats. Separate groups of animals were spinalized under isoflurane anesthesia alone, intramuscular ketamine anesthesia alone, or a combination of isoflurane and intrathecal ketamine. The TF was examined 24 h later, before and 30 min after an intrathecal injection of morphine. In the second experiment, the effect of intraperitoneal or intrathecal ketamine on the TF was assessed to separate groups of rats that underwent spinal transection or sham surgery under isoflurane anesthesia. Pretreatment with either systemic or intrathecal ketamine did not alter TF facilitation or morphine-induced antinociception in spinal rats. However, both systemic and intrathecal ketamine significantly increased TF latencies in spinal, relative to intact rats. These results indicate that ketamine did not prevent the development of spinal reflex facilitation, but it selectively reduced this reaction once it was established in spinal rats. The data support an involvement of EAAs in reflex facilitation produced by spinal transection.

Persistence of rubrospinal projections following spinal cord injury in the rat

Recent neurophysiological and magnetic resonance imaging studies of clinically "complete" human spinal cord injuries indicate that some patients have considerable subclinical function and substantial morphological integrity of descending spinal tracts. In contrast, extensive histopathological changes, including cell death, have been described in central nervous system nuclei projecting to the cord following experimental transection or hemisection of the spinal cord in animal models. We have used a rodent model of severe compression cord injury that more closely resembles the clinical pathophysiology to investigate the extent of the persistence of the rubrospinal projection. Counts of red nucleus neurons retrogradely labelled with Fluorogold demonstrate that in contrast to the results obtained with transection models, compression injuries of the spinal cord do not result in massive loss of rubrospinal projections, at least up to 8 weeks postinjury. The results also suggest that many of the axons persist distal to the lesion site and that they are functionally intact with respect to retrograde transport capabilities.

Bridging a complete transection lesion of adult rat spinal cord with growth factor-treated nitrocellulose implants

The ability of a substrate bound neurotrophic factor to promote growth of ascending sensory axons across a complete transection lesion of the rat spinal cord was examined in a transplantation model. Aspiration lesions created a 3 mm long cavity in the upper lumbar spinal cord of adult rats. Five weeks after injury two strips of nerve growth factor-treated nitrocellulose were implanted, each in a medio-lateral position, and apposed to the rostral and caudal surfaces of the cavity. Control animals received untreated nitrocellulose implants. Fetal spinal cord tissue was transplanted alongside and between these strips. Six weeks post transplantation, animals were sacrificed and vibratome sections through the grafts were processed for immunocytochemical demonstration of ingrowing axons expressing calcitonin gene-related peptide (CGRP-IR). Immunolabeled axons were abundant at the caudal interface between host tissue and the NGF-treated nitrocellulose implants, with dense fascicles of fibers abutting the grafts. As the distance from the caudal surface increased some CGRP-IR fibers extended into the fetal tissue although most appeared to remain oriented in a longitudinal course adjacent to the nitrocellulose. Labeled axons were evident along the entire length of the nitrocellulose and appeared to aggregate at the rostral tip of the implant, with many fibers extending into the host spinal cord rostral to the lesion/transplant site. When untreated nitrocellulose was implanted, fewer labeled axons appeared to extend beyond the caudal host-graft interface. Most CGRP-IR axons displayed limited association or contact with the untreated nitrocellulose in this condition. Computer-assisted quantitative analysis indicated that NGF-treated nitrocellulose supported regrowing host axons for nearly three times the length exhibited by axons associated with non-treated nitrocellulose implants. These results indicate that substrate bound nerve growth factor has the capacity to enhance the regrowth of ascending sensory axons across a traumatic spinal cord injury site. The potential to reestablish functional contacts across such a lesion may be heightened by the ability of neurotrophic factors to promote more extensive axonal regrowth.

Effects of age at cordotomy and subsequent exercise on contraction times of motor units in the cat

The contraction times (CTs) of functionally isolated motor units (MUs) in the soleus (SOL) and medial gastrocnemius (MG) muscles were determined in cats that had been spinalized at ages 2 (n = 15) or 12 (n = 9) wk and then either subjected to exercise on a treadmill or simply given manipulative care of the hindlimbs. The MUs were tested approximately 12 wk after the low-thoracic cordotomy, and comparisons were made with data from control animals. The CT of 50.9 ms obtained for SOL units (n = 163) in the spinal cats was 22% shorter than the mean of 65.0 ms for MUs (n = 57) from control cats (n = 4). Contrary to expectation, the CT in animals spinalized at 12 wk was significantly shorter than that in the 2-wk group. The CT for MG units (n = 105) in spinal cats was also significantly shorter (11%) than that in controls cats (n = 66, 6 cats), and those units identified by their high fatigue index as being of slow or fatigue-resistant type had a shorter CT than units with a low index. No distinction in CT of exercised and nonexercised groups was detected for either muscle. These findings are discussed in relation to the bearing influences of supraspinal and segmental origin have on CT duration in SOL and MG muscles during growth of the kitten. A slight, significant decrease (6%) in the fatigue index of SOL MUs (n = 144) was detected, but the values remained high (mean 0.87).

Ipsilateral referral of pain following cordotomy

We report a patient who developed ipsilateral referred pain following unilateral percutaneous cervical cordotomy (PCC). A right-sided PCC was performed on a 44-year-old woman who had been suffering from left groin and thigh pain caused by a fibrosarcoma. PCC produced analgesia below T7 on the left side, and the pain disappeared. A novel spontaneous pain with prominent allodynia occurred postoperatively in the right infraclavicular region (C3-C4). Strong pressure on the left groin where severe spontaneous pain and tenderness had been before PCC increased the new pain, and an epidural block which produced analgesia below T10 relieved the new pain. These facts indicate that the new pain was induced by afferent inputs from the originally painful region.

Flexion reflexes following anterolateral cordotomy in man: dissociation between pain sensation and nociceptive reflex RIII

Nociceptive flexion reflexes (RIII response) of the lower limbs were recorded after unilateral cervico-thoracic anterolateral cordotomy (ALC) in 7 patients. Pre-operative recordings were also obtained in 1 patient and follow-up observations in 3 patients. Flexion reflexes ipsilateral to cordotomy remained normal after surgery. Conversely, responses contralateral to the cordotomy exhibited two consistent postoperative changes: first, the RIII reflex was always dissociated from subjective pain, i.e., it appeared in the absence of any pain sensation, and, second, the RIII was depressed in the limb contralateral to ALC in 5 of 7 patients. RIII attenuation ranged from slight reduction to total abolition, and proved to be reversible in 2 of 3 patients tested during the follow-up. The reappearance of withdrawal reflexes was never accompanied by a recovery of pain sensation in the stimulated limb. We conclude that the dissociation between flexion reflexes and pain sensation, which was evidenced even in case of depressed RIII responses, should be attributable to the surgical lesion of spinothalamic fibers. Dissociation between RIII and subjective pain is a landmark indicating a lesion of the spinothalamic fibers, and may be used for the clinical assessment of spinothalamic dysfunction. Conversely, RIII depression after ALC does not depend upon the surgical lesion to the spinothalamic axons, but may be secondary to interruption of ascending spinoreticular fibers in the anterolateral quadrant, and/or of descending excitatory axons in the ventral cord.

[An experimental and clinical study of peripheral nerve potentials evoked by stimulating the spinal cord]

The purpose of this study was to evaluate a possible use of TNP (tibial nerve potentials evoked by stimulating the upper thoracic spinal cord) as waveforms for spinal cord monitoring. The results of an experimental study in cats indicate that TNP mainly conducts antidromically in the dorsal column of the spinal cord with a velocity of approximately 70 m/sec. TNP was not a motor-evoked potential, but it involved some potential conducted from the ventral root, which was very small in amplitude. In men, TNP consisted of several negative deflections of 20 msec in onset latency and 1 microV in amplitude. The peak latency and amplitude of TNP were used as parameters for monitoring. Using this method 40 cases with spinal disorders were monitored. During surgery, the peak amplitude of TNP fluctuated within a range of 20% of the control wave in 24 cases, increased in three cases, and decreased in six cases. There was no false negative monitoring. TNP could not be recorded in four cases, in which SC-DESCP was used for monitoring instead of TNP. TNP disappeared during operation in three cases and in one of the cases, the postoperative neurological status had deteriorated. The disappearance of TNP was considered to be a positive sign of postoperative neurological complications. This study has concluded that TNP can be used for spinal cord monitoring, especially in patients with thoracolumbar disorders.

Dorsal root entry zone lesions in the treatment of pain related to radiation-induced brachial plexopathy

Radiation-induced brachial plexopathy (RBP) is a rare (1-2% of irradiated patients) but serious disorder associated with supramaximal irradiation of the brachial plexus. Nerve compression by radiation-induced fibrosis in the absence of tumor recurrence is the hypothesized mechanism of RBP. It appears as severe pain in up to 20% of cases. Current medical and surgical therapies are ineffective in obtaining long-term pain control. Dorsal root entry zone (DREZ) lesions represent a potential therapy for the pain associated with RBP. The records of two patients with RBP with severe pain successfully treated with DREZ lesions are reviewed. Each received supramaximal radiation to the brachial plexus following resection of the malignancy and had pain within the irradiated area approximately 1 year following radiation without evidence of tumor recurrence by either computed tomography or magnetic resonance imaging. Electromyography patterns consistent with RBP were detected within the irradiated area in both patients. Pain was in the C8-T1 distribution and described as sharp and burning. Both patients failed to obtain pain relief with prior medical and/or surgical procedures. Histologic sections of nerves were taken at surgery and confirmed the diagnosis of radiation-induced injury. Within the immediate postoperative period both patients experienced excellent pain relief and continue to be pain free at 29-48-month follow-up observation. The DREZ lesions provide a safe and effective therapy for the pain associated with RBP.

[Treatment of pain in advanced-stage intra-abdominal neoplasms]

Different types of pain are present in far advanced intra-abdominal cancer, sometimes in the same site too. An accurate semeiological analysis of pain is important because different types of pain often differently respond to the available therapeutical tools. In this paper the results and the complications of the most important methods of pain management in far advanced intra-abdominal cancer are examined. Analysis of the data reveals that the association of more methods, pharmacological and non, should be a rule rather than the exception.

The location and function of respiratory fibres in the second cervical spinal cord segment: respiratory dysfunction syndrome after cervical cordotomy

After high cervical percutaneous cordotomy for pain in malignant disease, 12 patients died during sleep at postoperative intervals between 1 and 8 days. Nine died after a first cordotomy and three after a second (contralateral) procedure. All except one had known pulmonary disease before operation. The operated segment of the spinal cord (C2) was studied histologically after death. Superposition of lesion outlines made it possible to determine those parts of the lesioned areas common to all unilateral and bilateral cases respectively. All cases dying of presumed respiratory dysfunction syndrome had lesions involving the region of the anterolateral funiculus in the C2 segment containing "pain" fibres activated from the second to fifth thoracic dermatomes. The fibres whose destruction appeared to be responsible for respiratory dysfunction syndrome were completely intermingled with ascending "pain" fibres. The possibility of these fibres being afferent in function is discussed.

Chronic benign cervical pain syndromes. Surgical considerations

The results of surgical intervention for chronic benign pain syndromes are generally poor. In this review, pertinent ablative and modulatory techniques are reviewed, with specific reference to their utility for benign pain syndromes. With the possible exception of facet rhizotomy, the ablative modalities have little role in the management of benign pain syndromes. The more extensive techniques of cordotomy, dorsal root entry zone lesioning, ganglionectomy, and rhizotomy, have erratic results and high rates of complication. No long-term studies exist to support the use of facet rhizotomy. It is minimally invasive, however, and has little morbidity. In patients with benign refractory posterior column pain, facet rhizotomy may be worth consideration. Modulatory devices may have a role in benign pain syndromes. While the use of indwelling epidural catheters remains investigational, dorsal column stimulation has been widely studied. In representative reports, significant pain relief has been observed in up to 60% of patients (mean follow-up of two years). In the carefully selected patient, this may represent a valuable therapeutic adjunct.

The use of texture analysis for the discrimination of Nissl substance in neurons

Structural changes induced by cordotomy in the Nissl substance of identifiable spinal motoneurons innervating the white musculature of the European eel were quantified with the use of texture features calculated from digitized images. Data were evaluated and the motoneurons classified by using multivariate analysis. The study shows that there are differences in the structural organization of the Nissl substance of motoneurons taken from control and cordotomized fishes. Distinction could only be made by using texture features, as visual examination of the motoneurons did not reveal any alteration of the studied cellular substance. Reorganization of the Nissl substance might be the result of a changed protein metabolism or a changed neuronal activity pattern consequent upon cordotomy. The method employs quick and simple techniques and could be useful in several other neurobiological studies.

Hypercapnic blood flow reactivity not increased by alpha-blockade or cordotomy in piglets

We tested the hypothesis that differential sympathetic innervation explains the attenuated cerebral blood flow (CBF) response to hypercapnia (hyper) in fore-brain (fb) compared with brain stem in 1- to 2-wk-old piglets. In pentobarbital sodium-anesthetized piglets, CBF (microspheres) was measured during hypocapnia, normocapnia (normo), and hypercapnia [arterial CO2 partial pressure (PaCO2) of 25, 40, and 65 mmHg, respectively] in random sequence. After pretreatment values were obtained, piglets were randomized to undergo sham treatment (n = 5), high cervical spinal cord transection (n = 6), or pharmacological alpha-adrenergic blockade (prazosin 1 mg/kg + yohimbine 1 mg/kg, n = 6). After each experimental treatment, CO2 reactivity was again measured. Before experimental manipulation, hypercapnic reactivity [(CBFhyper - CBFnormo)/(PaCO2hyper - PaCO2normo)] in brain stem was approximately three times greater than in forebrain (e.g., sham; 3.6 +/- 0.8 vs. 1.2 +/- 0.3 ml.min-1.100 g-1.mmHg-1). Hypercapnic reactivity in forebrain was not increased by cord transection (1.4 +/- 0.3 vs. 1.1 +/- 0.2 ml.min-1.100 g-1.mmHg-1) or alpha-blockade (1.6 +/- 0.6 vs. 1.2 +/- 0.4 ml.min-1.100 g-1.mmHg-1). Likewise, hypercapnic cerebral vascular resistance (CVR) was unchanged by experimental treatment (e.g., CVRfb; cord transection 1.1 +/- 0.1 vs. 1.0 +/- 0.1; alpha-blockade 1.1 +/- 0.2 vs. 1.0 +/- 0.1 mmHg.ml-1.min-1.100 g-1). Hypocapnic vasoconstriction, however, was attenuated by both cord transection and alpha-blockade in forebrain and brain stem. We conclude that physiological stimulation of the noradrenergic component of the sympathetic nervous system does not explain regional differences in CBF reactivity during hypercapnia in 1- to 2-wk-old piglets.(ABSTRACT TRUNCATED AT 250 WORDS)

The algesic syndrome in spinal cord trauma

This article represents the author's experience in the diagnosis and management of pain in patients with spinal cord injuries, and describes methods applied to objectively evaluate pain syndromes and different surgical procedures to alleviate such pain. Instrumental methods for pain relief are also briefly discussed.