The effects of single and repetitive electrical stimulation of spinal afferent nerves and central nervous structures on the sympathetic nervous system.
Explore the source record for details and available documents.
Animals↗
SEARCH · PubMed Health
Results for “NERVES, SPINAL”
Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Restoration of shoulder abduction by nerve transfer in avulsed brachial plexus injury: evaluation of 99 patients with various nerve transfers.
During the 5-year period between 1987 and 1991, 99 patients with total root or upper root (C5, C6, or C7) injuries were treated by nerve transfer to obtain shoulder abduction. More than eight different combinations of coaptation between donor nerves (intercostal nerves, phrenic nerve, spinal accessory nerve, ipsilateral C7, or cervical motor nerves) and recipient nerves (suprascapular nerve, axillary nerve, and upper trunk or C5) were applied. All patients had at least 2 years of follow-up. Different results were obtained in each category. Simultaneous neurotization of the suprascapular and axillary nerves with the phrenic and spinal accessory nerves obtained much better and more reliable shoulder abduction. Neurotization of the C5 spinal nerve by multiple nerve transfers was another good option that yielded good shoulder abduction in a single patient. If the phrenic nerve was traumatized, neurotization of the suprascapular nerve solely with the spinal accessory nerve was still capable of achieving an acceptable range of shoulder abduction.
Adolescent↗
Physiology of spinal cord, nerve root and peripheral nerve compression.
Explore the source record for details and available documents.
Disease↗
Pressure increase in the dorsal root ganglion following mechanical compression. Closed compartment syndrome in nerve roots.
Spinal nerve roots including the dorsal root ganglion (DRG) often are mechanically deformed in connection with degenerative and traumatic conditions of the spine. However, the pathophysiology underlying various functional changes, including pain production, in such conditions is incompletely known. In this study, the tissue fluid pressure in the DRG of L5 nerve roots of rats was measured before and after compression. Normal values were found to be 3.7 +/- 0.3 cm H2O (2.7 +/- 0.2 mm Hg). After mechanical compression, the endoneurial fluid pressure in the ganglia rose to 9.6 +/- 1.7 cmk H2O (7.1 +/- 1.2 mm Hg) (P less than 0.001). Histologic examination revealed edema and haemorrhage in the endoneurial space of the DRG. Pressure increase in the DRG as a result of mechanical deformation by, for example, a herniated disc might be expected to reduce blood flow to the sensory nerve cell bodies in the DRG. This may be a mechanism underlying the production of nerve root pain, which previously has not been described.
Animals↗
Surgical anatomy of spinal accessory nerve: is trapezius functional deficit inevitable after division of the nerve?
The course of spinal accessory nerve in the posterior triangle, the innervation of the sternocleidomastoid and trapezius muscles and the contributions from the cervical plexus were studied in 20 cadaveric dissections. The nerve was most vulnerable to iatrogenic injuries after leaving the sternocleidomastoid. Direct innervation of trapezius by cervical plexus branches was noted in five dissections, whereas connections between the cervical plexus and the spinal accessory nerve were observed in 19 dissections. These were usually under the sternocleidomastoid (proximal to the level of division of the nerve in nerve transfer procedures). Although the contribution from the cervical plexus to trapezius innervation is considered minimal, trapezius function can be protected in neurotization procedures by transecting the spinal accessory nerve distal to its branches to the upper position of trapezius.
Accessory Nerve↗
Restoration of elbow flexion in brachial plexus avulsion injury: comparing spinal accessory nerve transfer with intercostal nerve transfer.
This study was performed to compare the clinical outcome of 2 types of commonly used nerve transfers, the spinal accessory nerve transfer and the intercostal nerve transfer. This study was a prospective randomized parallel trial involving 205 patients presenting between 1989 and 1994. All patients were males ranging in age from 16 to 43 years. All patients underwent surgery within 6 months of injury. Spinal accessory nerve transfer was performed in 130 patients; better results were obtained in terms of less operative time, fewer blood transfusions, fewer immediate complications, and better motor function (very good and good power in 83% of patients). Intercostal nerve transfer was performed in 75 patients; better results were observed in terms of earlier electromyographic evidence of motor reinnervation, improvement in protective sensation, and reduction of pain. However, very good and good motor recovery was observed in only 64% of patients. There was no significant difference with regard to tidal volume, vital capacity, and the FEV1 to FEV ratio before and after surgery in either group. Smoking adversely affected the rate of recovery. Spinal accessory nerve transfer should be used when motor function of the elbow flexors is the major concern. Intercostal nerve transfer should be performed in patients who need both motor and sensory reconstruction and in those who have chronic pain syndrome after brachial plexus injury.
Adolescent↗
Assessment of neurolymphomatosis by brachial plexus biopsy and PET/CT. Report of a case.
OBJECTIVE: To report a biopsy-proven neurolymphomatosis in a young woman with previous non-Hodgkin's lymphoma (NHL) of uterine cervix. PATIENT: The patient presented with a painful brachial plexopathy and developed multiple cranial and spinal nerve palsies. METHODS AND RESULTS: The diagnosis was achieved by an open brachial plexus biopsy. A PET/CT study was used to assess the full extent of the disease and showed involvement of additional cranial nerves and spinal nerve roots. A complete although short lasting clinical and radiological response was achieved by means of systemic high dose methotrexate treatment combined with rituximab and intra-CSF injections of cytarabine.
Adult↗
[Nerve root & spinal cord compression caused by cervical disk diseases in aged].
Explore the source record for details and available documents.
Disease↗
Anatomic issues related to cervical and lumbosacral radiculopathy.
The anatomy of cervical and lumbar spinal nerves is well established. Knowledge of the normal and pathoanatomy of impingement of these roots is helpful in the diagnosis of radiculopathy in many cases. Frequently, symptoms and signs do not correlate with expected anatomical patterns. Variations of nerve roots, spinal nerves, and plexuses occur commonly. Neuroanatomical anomalies and musculoskeletal abnormalities account for many of the variations seen with unexpected radicular patterns. Unfortunately, the delineation of segmental innervation has been achieved by several different methods and definitive studies are lacking. Although there is a regular and orderly progression of innervation within each individual, it is likely that innervation patterns differ considerably between individuals.
Animals↗
A- and C-reflexes elicited in cardiac sympathetic nerves by single shock to a somatic afferent nerve include spinal and supraspinal components in anesthetized rats.
The spinal and supraspinal components of both A- and C-reflexes were studied in the somato-cardiac sympathetic reflex discharges elicited by a single electrical shock either to a spinal (T3-4) afferent nerve or to a limb (tibial) afferent nerve in urethane anesthetized rats. In central nervous system (CNS) intact rats, a single shock to a T3-4 spinal afferent nerve produced early and late A-reflex discharges with latencies of 20 +/- 1 ms and 62 +/- 6 ms, respectively, and a C-reflex with a latency of 136 +/- 9 ms in a cardiac sympathetic efferent nerve. After spinalization at the first cervical level, stimulation of the same spinal afferent nerve produced an A-reflex with the same latency as the early A-reflex in CNS-intact rats and a C-reflex with a latency of 86 +/- 3 ms. The amplitude of the early A-reflex became augmented after spinal transection. On the other hand, a single shock to a tibial afferent nerve evoked an A-reflex discharge with a latency of 41 +/- 2 ms and a C-reflex discharge with a latency of 210 +/- 13 ms in CNS-intact rats. These A- and C-reflexes elicited by stimulation of a tibial afferent nerve were not observed after spinalization. It was concluded that cardiac sympathetic A- and C-reflex discharges evoked by stimulation of a segmental spinal afferent nerve in CNS-intact rats are of spinal and supraspinal origin, and those evoked by tibial nerve stimulation are of supraspinal origin. The spinal reflex pathway is segmentally organized, because the spinal reflex is evoked only when stimulation is delivered to afferent nerves close to the cardiac sympathetic outflow segments. With the CNS intact, the spinal reflex component is depressed by descending inhibitory pathways originating in the brain.
Adrenergic Fibers↗
[Management of iatrogenic lesions of the spinal accessory nerve].
Lesions of the spinal accessory nerve are usually iatrogenic, especially after lymph node extirpation on the neck. Between 1994 and 2003, 31 patients were operated on in the Neurosurgical Department of the University of Ulm for iatrogenic lesions of the XIth cranial nerve. Of 31 patients, 22 had undergone a previous lymph node extirpation, 2 had been injured during a selective peripheral denervation for spasmodic torticollis, and the other 7 patients by different causes. The neurosurgical intervention was performed 0-19 months after trauma (mean 7.2 months). All patients showed paresis/atrophy of the trapezius muscle, and the abduction of the shoulder was markedly reduced. Additional neck and/or shoulder pain was present in 29 of 31 cases. In seven cases, the nerve was compressed by scar tissue and subsequently treated by external neurolysis. Ten patients underwent an end-to-end anastomosis; autologous sural nerve grafting was necessary in 13 cases. After a mean follow-up of 12.6 months, 7 of 31 patients completely recovered. Of 31 patients, 19 experienced partial relief of pain and weakness. Only five patients remained unchanged. The clinical findings after autologous nerve grafting, end-to-end reconstruction, or external neurolysis did not show any significant differences. Microsurgical reconstruction of iatrogenic injury of the spinal accessory nerve is very promising if the interval between trauma and surgical revision is less than 6 months. Up to 12 months, partial recovery can be achieved. Outcome after longer delay is unsatisfactory.
Accessory Nerve↗
Spinal and vagal projections to the sympathetic trunk of the wrasse, Halichoeres poecilopterus.
The sympathetic preganglionic neurons of the teleost, Halichoeres poecilopterus, were identified by retrograde axonal tracing. After horseradish peroxidase was applied to the sympathetic trunk, labeled neurons were found at the caudalmost level of the medulla, in the spinal cord near the fourth spinal nerve root (rostral spinal group), and in the spinal cord from rostral to the sixth spinal nerve root to caudal to the tenth spinal nerve root (caudal spinal group). The rostral spinal group has three cell columns segregated mediolaterally from the central gray zone to the lateral funiculus. Labeled neurons were found predominantly on the side ipsilateral to the application. In the caudal spinal group, labeled neurons were found bilaterally in the central gray zone. This condition is different from that previously reported in the puffer fish and filefish. The labeling in the medulla suggests that the preganglionic neurons in the brainstem may send fibers to the sympathetic trunk of this fish, although their peripheral targets are unknown.
Animals↗
The surgical anatomy of the spinal accessory nerve and the internal branch of the superior laryngeal nerve.
Injury to the spinal accessory nerve may occur during conservation neck dissection. In supraglottic laryngectomy preservation of the internal branch of the superior laryngeal nerve has largely been ignored. Cadaver dissection and diagrams are used to review the surgical anatomy of these two structures. Particularly important are the relationship of the spinal accessory nerve to the sternocleidomastoid muscle, its interaction with the cervical plexus, and its superficial path inferiorly. Landmarks for the identification of the internal branch of the superior laryngeal nerve are indicated, and technique for preservation is described. An intact accessory nerve can be efficiently preserved thereby eliminating the shoulder syndrome. Significant sparing of the internal branch of the superior laryngeal nerve can be routinely accomplished as an aid in minimizing postoperative aspiration.
Accessory Nerve↗
CT-assisted chemonucleolysis.
The safety and success rate of chemonucleolysis are largely dependent on correct needle insertion. The neurological complications of chemonucleolysis are related to inadvertent puncture of the dura, nerve root and/or spinal nerve. To avoid this complication, a puncture angle of 50 degrees to 60 degrees above the sagittal plane is widely recommended (1). Our CT study of the location of the spinal nerve L4-L5 and L5-S1 demonstrates a great variability of this location and also explains some of the possible hazards of 50 degrees to 60 degrees puncture (2). The CT-evaluation of the relationship between the nerve root, spinal nerve and apophyseal joint with respect to the puncture angle is suitable. In our experience, this method is helpful for fast, safe and easy insertion of the needle.
Humans↗
NMDA as well as non-NMDA receptors in phrenic nucleus mediate respiratory effects of carotid chemoreflex.
An in vivo model was used to identify the transmitter/receptor mechanisms in the phrenic nucleus that mediate carotid chemoreceptor responses. Adult male Wistar rats, anesthetized with urethan, were fixed in a stereotaxic instrument, and the blood pressure and heart rate were monitored. The rats were immobilized and artificially ventilated to maintain the end-tidal CO2 at 4.5-5%. The vagus nerves were bilaterally sectioned, and a pneumothorax was produced. Activity was recorded from one of the phrenic nerves. The spinal cord was exposed from C1 to T1 vertebral level. The dorsal and ventral rootlets of spinal nerves C3, C5, and C6, ipsilateral to the phrenic nerve from which electrical activity was recorded, were sectioned; the dorsal and ventral roots of spinal nerve C4 were left intact. Thus the phrenic nerve bursts recorded in this preparation represented output from a portion of the phrenic nucleus located in the ipsilateral C4 spinal segment. Carotid chemoreceptor stimulation by N2 inhalation increased the amplitude as well as the frequency of phrenic nerve bursts. Microinjections (50 nl) of a specific N-methyl-d-aspartic acid (NMDA) receptor antagonist (D(-)-2-amino-7-phosphonoheptanoic acid, AP-7, 50-100 mM) into the phrenic nucleus decreased the N2-induced increase in amplitude, but not the frequency, of phrenic nerve bursts. Likewise microinjections of a specific non-NMDA receptor antagonist (1,2,3,4-tetrahydro-6-nitro-2,3-dioxobenzoquinoxaline-7-sulfonamid e, NBQX, 0.5-1 mM) into the phrenic nucleus decreased the N2-induced increase in phrenic nerve burst amplitude. When AP-7 and NBQX were microinjected into the phrenic nucleus sequentially within an interval of 5 min, a drastic reduction in the N2-induced increase in phrenic nerve burst amplitude was observed. These observations suggest that both NMDA and non-NMDA receptors located in the phrenic nucleus are involved in the mediation of phrenic nerve responses to the carotid chemoreceptor stimulation.
2-Amino-5-phosphonovalerate↗
[Spinal accessory nerve neurinoma in the C2 spinal canal. Case report].
Explore the source record for details and available documents.
Accessory Nerve↗
Relationship between the firing frequency of injured peripheral neurons and inhibition of firing by sodium channel blockers.
UNLABELLED: Animal models of neuropathic pain in which a peripheral nerve is damaged result in spontaneous activity in primary afferents that can be inhibited by intravenous administration of sodium channel blockers. Many of these compounds exhibit use-dependent block of sodium current, leading to the prediction that they should more readily inhibit neurons that fire at higher frequencies. This prediction was tested in 2 rat models of nerve injury, L5 spinal nerve section and sciatic nerve section. Sciatic nerve section produced average firing frequencies that were higher than spinal nerve section and often manifested as high-frequency bursting. Inhibition of firing by intravenous sodium channel blockers was longer lasting in this model. Within each model, higher frequency of firing did not translate into more effective block. In the spinal nerve section model, there was a robust inverse correlation between frequency and inhibition. Within the sciatic section model, only neurons that fired in rhythmic bursts were inhibited, and again, those firing at lower mean frequencies were more effectively inhibited. These results indicate that the efficacy of sodium channel blockers depends on the nature of the injury and the pattern of the resulting activity rather than simply the frequency of action potentials generated. PERSPECTIVE: This study examines the ability of frequency-dependent sodium channel blockers to inhibit spontaneous firing of injured peripheral nerves in vivo. It outlines the conditions under which inhibition is more and less effective and will provide insight into conditions under which sodium channel blockers are likely to be therapeutically useful.
Anesthetics, Local↗
VR1 protein expression increases in undamaged DRG neurons after partial nerve injury.
Changes in phenotype or connectivity of primary afferent neurons following peripheral nerve injury may contribute to the hyperalgesia and allodynia associated with neuropathic pain conditions. Although earlier studies using partial nerve injury models have focused on the role of damaged fibres in the generation of ectopic discharges and pain, it is now thought that remaining undamaged fibres may be equally important. We have examined the expression of the sensory neuron-specific cation channel Vanilloid Receptor 1 (VR1), an important transducer of noxious stimuli, in three models of nerve injury in the rat, using anatomical separation or fluorescent retrograde tracers to identify damaged or undamaged sensory neurons. After total or partial sciatic nerve transection, or spinal nerve ligation, VR1-immunoreactivity (IR) was significantly reduced in the somata of all damaged dorsal root ganglion (DRG) neuronal profiles, compared to controls. However, after partial transection or spinal nerve ligation, VR1 expression was greater in the undamaged DRG somata than in controls. Unexpectedly, after L5 spinal nerve ligation, VR1-IR of the A-fibre somata increased approximately 3-fold in the uninjured L4 DRG compared to controls; a much greater increase than seen in the somata with C-fibres. Furthermore, we found that VR1-IR persisted in the transected sciatic nerve proximal to the lesion, despite its down-regulation in the damaged neuronal somata. This persistence in the nerve proximal to the lesion after nerve section, together with increased VR1 in DRG neurons left undamaged after partial nerve injury, may be crucial to the development or maintenance of neuropathic pain.
Animals↗