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Query: UMLS:C0030193 (pain)
 261,466 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cebus albifrons monkeys were trained to escape electrical stimulation of either leg at five intensities, spanning a range from mild tingle to intense but tolerable pain, as judged by human observers who experienced the same stimuli. The average duration of stimulation received by the animals at each intensity was plotted for each leg during the period required for recovery of responsiveness to noxious electrical stimulation following ventrolateral spinal cordotomy. Recovery of escape responding was observed similarly following subsequent lesions to the spinal cord, in an attempt to define the pathways that subserve pain conduction after readjustment from cordotomies that produced substantial deficits of escape behaviour. The most enduring elevations of duration of stimulation by lesion I (left cordotomy) were produced by lesions that involved all of the ventrolateral column and most or all of one or both ventral columns. Secondary lesions of the dorsal columns, Lissauer's tract and the dorsolateral columns, in various combinations, did not produce long-term effects on escape responding. In contrast, a complete ventral hemisection produced a pronounced bilateral deficit that did not recover fully over three hundred and five post-operative days. The major conclusions are: (1) that the dorsal pathways do not play a major role in the rostral conduction of information critical for pain perception in monkeys, even though these pathways receive input from high threshold receptors; and (2) in order to produce a lasting decrease of pain sensitivity in primates by spinal surgery, the lesion must be bilateral and must involve both the ventrolateral and ventral columns.
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PMID:Loss and recovery of reactivity to noxious stimuli in monkeys with primary spinothalamic cordotomies, followed by secondary and tertiary lesions of other cord sectors. 11 Mar 88

The tract of Lissauer receives small caliber dorsal root fibers in addition to axons arising from dorsal horn neurons. The termination of Lissauer's tract and dorsal root fibers was examined in the C7 segment of the rhesus monkey spinal cord. The distribution of normal dorsal root afferents was mapped by labelling the C7 dorsal root ganglion with tritiated amino acids, and then compared with the degeneration of C7 dorsal root fibers following an intradural dorsal rhizotomy. To focus on the distribution of the small afferents, the degeneration following a Lissauer tractotomy was compared with the degeneration following dorsal rhizotomy and following selected lesions involving the large afferents. The survival times following the lesions and rhizotomies were varied to facilitate identification of groups of fibers and terminals which might degenerate at different rates. Both large and small diameter dorsal root afferents were found to exhibit the same rostro-caudal topography within the dorsal horn. The C7 root axons and terminals distribute throughout the mid-C7 dorsal horn grey. Proceeding rostrally through C6, the majority of the C7 root fibers ending in laminae I-IV shift to a lateral position. Proceeding caudally through C8, the C7 root fibers shift medially. Few of the small diameter C7 afferents entering via Lissauer's tract extend above C6 or below C8. Large diameter C7 afferents, arising as dorsal column collaterals, can extend several segments above and below C7. Autoradiography revealed label in all dorsal horn laminae, the heaviest always occurring in the substantia gelatinosa. After one day, label was absent over dorsal column and Lissauer's tract axons, suggesting that the label was mainly associated with fine axonal branches or possibly terminals. After six to ten days many axons were labelled and could be traced into the dorsal and ventral horn. Degeneration from the rhizotomies and lesions, as demonstrated with Fink-Heimer and Nauta methods, depended on the survival time. No degeneration products were present before three days. The large afferents begin to degenerate within the dorsal horn after three to four days and mainly terminate in laminae IV-VI; by 12 days they can also be traced into the intermediate and ventral grey. The small afferents, which include those serving pain and temperature sensibility, arise from the tract of Lissauer and distribute to laminae I, II and III. The tract of Lissauer consists of two populations, each containing small afferents. One population degenerates at three to five days and distributes mainly to laminae II and III (substantia gelatinosa); the other degenerates around 12 days and distributes mainly to lamina I and the outer zone of II. It is suggested that the exclusive termination of the small afferents to laminae I, II and III may be correlated with certain unique histochemical properties (e.g., high substance P and high opiate receptor binding levels) of these same dorsal horn areas...
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PMID:Distribution of the tract of Lissauer and the dorsal root fibers in the primate spinal cord. 40 97

Intrauterine development and postnatal maintenance of dorsal root ganglion neurons are abnormal in familial dysautonomia, an autosomal recessive disorder associated with autonomic, motor and sensory deficits. Normally, dorsal root ganglion weight increases with age. This does not occur in the cervical plexus ganglia of dysautonomic patients. Neurons in dorsal root ganglia are found to be markedly diminished in the youngest patients and slow degeneration causes further depletion with age. Quantitative studies on C8 dorsal root ganglia show the normal neuron content to be between 42,500 and 53,600. In 3 patients with familial dysautonomia the range was 4,090-8,590 with the smallest number being in the oldest patient. Lateral root entry zones and Lissauer's tracts are severely depleted of axons. In older patients loss of dorsal column myelinated axons becomes evident and is first seen in lumbar fasciculus gracilis, cervical fasciculus cuneatus and interfascicular fasciculus. Temperature sensation is markedly impaired from infancy in familial dysautonomia. Loss of pain sensation is prominent and worsens with age. Vibration sense diminishes in adolescence and coordination of limb movements becomes poor in older patients. Neuron depletion in dorsal root ganglia and the progressive pattern of cord changes correlate well with these clinical observations.
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PMID:Quantitative studies of dorsal root ganglia and neuropathologic observations on spinal cords in familial dysautonomia. 62 61

Congenital indifference to pain is often mistaken for congenital insensitivity. It is characterized by the occurrence since childhood of lesions, mainly cutaneous and osteoarticular secondary to strictly painless traumas. However, despite the lack of pain, the patient is able to discriminate a painful stimulus. Autopsy shows no abnormality of the nervous system. A dysfunction of the central endomorphinic systems has been suggested. Congenital analgesia is associated with anhidrosis in Swanson's syndrome (in which Lissauer the tractus is absent in the spinal cord) and with dysautonomia in Riley-Days's disease (in which there is a lack of amyelicinic fibres). On account of these data, some authors refuse the autonomy of congenital indifference and classify it in the group of the various autonomic and sensory neuropathies. However it seems justified to acknowledge the congenital analgesia with two varieties: congenital indifference in which there is no sensation of pain but normal sensory pathway and tonic function of endomorphinic system, congenital insensitivity in which the painful stimulus is not transmitted to the central nervous system.
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PMID:[Congenital indifference and congenital insensitivity to pain]. 138 39

The authors report on a series of 53 bedridden patients suffering from harmful spasticity in one (6) or both (47) lower limbs, who were treated with microsurgical DREZ-otomy. Surgery was performed to treat fixed abnormal postures in flexion in 49 patients and hyperextension in 3, and, additionally, to treat pain in 37 patients. Microsurgical DREZ-otomy was introduced in 1972, on the basis of anatomical studies of the human dorsal root entry zone (DREZ) showing a topographical segregation of the afferent fibers according to their size and functional destinations. It consists of a 2 mm deep microsurgical lesion directed at a 45 degrees angle in the posterolateral sulcus and penetrating the dorsal root entry zone in its ventrolateral aspect, at the level of all the rootlets considered involved in spasticity (and pain). It destroys mainly the lateral (nociceptive) and central (myotatic) afferent fibers as well as the facilitatory medial part of the Lissauer tract, while sparing most of the medial (lemniscal) fibers, the suppressor lateral part of the Lissauer tract, and more or less of the dorsal horn (DH). The postoperative results were evaluated after a mean follow-up period of 3 years and 4 months. Both spasticity and spasms were significantly decreased or suppressed in 75% and 88.2% of the patients, respectively. When present, pain was relieved without abolition of sensation in 91.6%. These benefits--combined with complementary orthopedic surgery in 23 patients--resulted in either disappearance or marked reduction of the abnormal postures in 85.3% of the patients and of articular limitations in 96.8%. Mild-to-severe complications occurred in 25 patients and precipitated or were responsible for death in 5. This is explained by the fact that the general and neurological conditions of most of the patients--especially those affected by multiple sclerosis--were precarious. MDT has, however, enabled a majority of these severely disabled patients to sit and lie comfortably, and has allowed them to reach a significantly improved quality of life.
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PMID:Microsurgical DREZ-otomy for the treatment of spasticity and pain in the lower limbs. 271 74

The Authors report 8 cases of Failed Lumbar Disk Syndrome (FLDS), on 210 patients operated for slipped disk. Risk factors and the concept that an abnormality involving either neurons in the substantia gelatinosa or internucial fibers in Lissauer's tract is responsible for pain in patients with FLDS are discussed. Since iatrogenic deafferentation pain response to almost all current forms of therapy is generally poor, the most rational approach remains prevention.
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PMID:Failed lumbar disk syndrome. 296 79

The authors report a series of 53 bedridden patients having harmful spasticity in one (6) or both (47) lower limb(s) and treated with selective posterior rhizotomy (SPR) in the dorsal root entry zone (DREZ). This severe spasticity was associated with irreducible flexion contracture in 49 cases and hyperextension in 3 others. 37 of these patients also had painful manifestations. The method was introduced in 1972 on the basis of anatomical studies of the DREZ in humans which showed a topographical segregation of the afferent roots according to their anatomico-functional destinations. The technique consists of a 2 mm deep DREZ microsurgical cut directed at a 45 degree angle into the posterior lateral sulcus just ventral to DREZ and Lissauer's tract of the spinal cord. The procedure was carried out at each sensory rootlet considered to be responsible for the harmful spasticity and pain. SPR interrupts selectively the lateral nociceptive and central myotactic afferent fibers curving toward Lissauer's tract and the anterior spinal cord, while sparing most of the medial lemniscal fibers curving toward the dorsal columns, as well as the fibers of the inhibitory circuitry of Lissauer's tract and dorsal horn. The results were evaluated after a 1 to 14 year follow-up. Mild to severe complications occurred in 25 patients (47.1%) and were responsible for death in 5 (9.4%). Both spasticity and spasm were significantly decreased or completely eliminated in 75% and 88.2% respectively; when present, pain was relieved without a total suppression of sensation in 91.6%. These benefits-combined with complementary orthopedic surgery in 23 patients--resulted in either a complete resolution or marked reduction of the abnormal postures and articular limitations (85.2% complete and 96.75 marked reduction). Because of the extreme severity of the pre-operative neurological deficits in almost all the patients in this series, surgery improved voluntary movements with a significant functional benefit in only 5 cases and vesico-sphincter function in none. Thanks to its valuable effects on hyperspasticity and pain, SPR in the DREZ made it possible for these very disable patients to be more comfortable in bed and wheel-chair and it allowed effective nursing and kinesitherapy to be resumed.
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PMID:[Selective posterior rhizotomy at the posterior radiculomedullary junction in the treatment of hyperspasticity and pain in the lower limbs]. 332 98

Pain relief was evaluated in 40 patients with various types of deafferentation pain that were treated with dorsal root entry zone (DREZ) lesions produced with microsurgical lasers. Good long-term pain relief was evident in some paraplegics and in all patients with brachial plexus avulsion. Several other small subgroups of patients benefited from laser DREZ lesions as well. Pain associated with arachnoiditis and peripheral nerve injury or neuropathy did not respond to laser DREZ lesioning. Based upon the smaller lesion dimensions produced with the lasers, it is proposed that interruption of impulses in the tract of Lissauer may be a mechanism of pain control in patients that responded to laser DREZ lesions.
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PMID:Pain control with laser-produced dorsal root entry zone lesions. 338 2

The authors report a series of 16 hemiplegic patients suffering from harmful spasticity in the upper limb and treated with selective posterior rhizotomy (SPR) in the dorsal root entry zone (DREZ). This severe spasticity was associated with irreducible abnormal postures in flexion in 11 cases and painful manifestations in 12. The method was introduced in 1972 on the basis of anatomical studies of the DREZ in humans, in which a topographical segregation of the root afferents, according to their anatomicofunctional destinations, has been shown. It consists of a DREZ microsurgical lesion 1 to 2 mm in depth and directed at a 45 degree angle, performed ventrolaterally in the posterolateral sulcus of the spinal cord and into the internal part of the Lissauer's tract. The procedure is carried out in each rootlet of the posterior roots considered to be responsible for the harmful spasticity. SPR interrupts selectively the (lateral) nociceptive and (central) myotactic afferent fibers connecting the motor neurons, while sparing most of the (medial) lemniscal fibers and the inhibitory circuitry of Lissauer's tract and the dorsal horn. The results were evaluated after a 1- to 12-year follow-up. There were no deaths and no general complications; in 1 case a loss of motility in the leg ipsilateral to the procedure occurred. The excess of spasticity was slightly diminished (2 cases), markedly reduced (9 cases), or totally abolished (5 cases), making possible an improvement in voluntary movements in 8 patients and at least a good passive mobilization in 7 further cases. In 1 case only, a marked tendency for spasticity to return was observed. Of the 12 patients with painful manifestations, 9 were completely relieved and 3 improved. These beneficial effects on both spasticity and pain led to a gain in functional status in 93% of cases.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Selective posterior rhizotomy in the dorsal root entry zone for treatment of hyperspasticity and pain in the hemiplegic upper limb. 371 7

We studied the distribution of sugar residues in the oligosaccharide chains of complex carbohydrates in tissue sections of rat spinal cord, brainstem, and sensory ganglia using twelve lectin-horseradish peroxidase conjugates. Glycoconjugates containing terminal galactose residues were localized apparently in the Golgi apparatus in a population of predominantly small B-type neurons in spinal and trigeminal ganglia. Large A-type neurons rarely showed reactivity with galactose-binding lectins. A cells stained for glycoconjugates with N-glycosidically linked oligosaccharides and glycogen. The central and peripheral processes of the small neurons, mostly unmyelinated C fibers in sensory roots and spinal nerves, contained an abundance of glycoconjugates with terminal alpha-galactose residues. The central projections and terminals of small to medium-sized primary sensory neurons in the spinal and trigeminal ganglia were visualized in Lissauer's tract and the substantia gelatinosa in the spinal cord, and in the spinal trigeminal tract and the nucleus trigeminus in the lower medulla with lectins specific for terminal alpha-galactose residues. In addition, fibers of the solitary system and the area postrema were reactive with these lectins. The peripheral and central nervous system elements with affinity for galactopyranosyl-specific lectins correspond in distribution with neuroanatomical regions thought to be involved in the transmission and relay of somatic and visceral afferent inputs such as pain and temperature. Such specific localization of a glycosubstance to a distinct subpopulation of neurons and their peripheral and central processes suggests that the particular glycoconjugate may be of physiological significance.
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PMID:Histochemical localization of galactose-containing glycoconjugates in sensory neurons and their processes in the central and peripheral nervous system of the rat. 404 82


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