Salvage of cervical motor radiculopathy using peripheral nerve transfer reconstruction.

PubMed

Afshari, Fardad T; Hossain, Taushaba; Miller, Caroline; Power, Dominic M

2018-05-10

Motor nerve transfer surgery involves re-innervation of important distal muscles using either an expendable motor branch or a fascicle from an adjacent functioning nerve. This technique is established as part of the reconstructive algorithm for traumatic brachial plexus injuries. The reproducible outcomes of motor nerve transfer surgery have resulted in exploration of the application of this technique to other paralysing conditions. The objective of this study is to report feasibility and increase awareness about nerve transfer as a method of improving upper limb function in patients with cervical motor radiculopathy of different aetiology. In this case series we report 3 cases with different modes of injury to the spinal nerve roots with significant and residual motor radiculopathy that have been successfully treated with nerve transfer surgery with good functional outcomes. The cases involved iatrogenic nerve root injury, tumour related root compression and degenerative root compression. Nerve transfer surgery may offer reliable reconstruction for paralysis when there has been no recovery following a period of conservative management. However the optimum timing of nerve transfer intervention is not yet identified for patients with motor radiculopathy.

α-Synuclein pathology in the cranial and spinal nerves in Lewy body disease.

PubMed

Nakamura, Keiko; Mori, Fumiaki; Tanji, Kunikazu; Miki, Yasuo; Toyoshima, Yasuko; Kakita, Akiyoshi; Takahashi, Hitoshi; Yamada, Masahito; Wakabayashi, Koichi

2016-06-01

Accumulation of phosphorylated α-synuclein in neurons and glial cells is a histological hallmark of Lewy body disease (LBD) and multiple system atrophy (MSA). Recently, filamentous aggregations of phosphorylated α-synuclein have been reported in the cytoplasm of Schwann cells, but not in axons, in the peripheral nervous system in MSA, mainly in the cranial and spinal nerve roots. Here we conducted an immunohistochemical investigation of the cranial and spinal nerves and dorsal root ganglia of patients with LBD. Lewy axons were found in the oculomotor, trigeminal and glossopharyngeal-vagus nerves, but not in the hypoglossal nerve. The glossopharyngeal-vagus nerves were most frequently affected, with involvement in all of 20 subjects. In the spinal nerve roots, Lewy axons were found in all of the cases examined. Lewy axons in the anterior nerves were more frequent and numerous in the thoracic and sacral segments than in the cervical and lumbar segments. On the other hand, axonal lesions in the posterior spinal nerve roots appeared to increase along a cervical-to-sacral gradient. Although Schwann cell cytoplasmic inclusions were found in the spinal nerves, they were only minimal. In the dorsal root ganglia, axonal lesions were seldom evident. These findings indicate that α-synuclein pathology in the peripheral nerves is axonal-predominant in LBD, whereas it is restricted to glial cells in MSA. © 2015 Japanese Society of Neuropathology.

[Possibility of cauda equina nerve root damage from lumbar punctures performed with 25-gauge Quincke and Whitacre needles].

PubMed

Reina, M A; López, A; Villanueva, M C; De Andrés, J A; Martín, S

2005-05-01

To assess the possibility of puncturing nerve roots in the cauda equina with spinal needles with different point designs and to quantify the number of axons affected. We performed in vitro punctures of human nerve roots taken from 3 fresh cadavers. Twenty punctures were performed with 25-gauge Whitacre needles and 40 with 25-gauge Quincke needles; half the Quincke needle punctures were carried out with the point perpendicular to the root and the other half with the point parallel to it. The samples were studied by optical and scanning electron microscopy. The possibility of finding the needle orifece inserted inside the nerve was assessed. On a photographic montage, we counted the number of axons during a hypothetical nerve puncture. Nerve roots used in this study were between 1 and 2.3 mm thick, allowing the needle to penetrate the root in the 52 samples studied. The needle orifice was never fully located inside the nerve in any of the samples. The numbers of myelinized axons affected during nerve punctures 0.2 mm deep were 95, 154, and 81 for Whitacre needles, Quincke needles with the point held perpendicular, or the same needle type held parallel, respectively. During punctures 0.5 mm deep, 472, 602, and 279 were affected for each puncture group, respectively. The differences in all cases were statistically significant. It is possible to achieve intraneural puncture with 25-gauge needles. However, full intraneural placement of the orifice of the needle is unlikely. In case of nerve trauma, the damage could be greater if puncture is carried out with a Quincke needle with the point inserted perpendicular to the nerve root.

Finite Element Analysis of the Effect of Epidural Adhesions.

PubMed

Lee, Nam; Ji, Gyu Yeul; Yi, Seong; Yoon, Do Heum; Shin, Dong Ah; Kim, Keung Nyun; Ha, Yoon; Oh, Chang Hyun

2016-07-01

It is well documented that epidural adhesion is associated with spinal pain. However, the underlying mechanism of spinal pain generation by epidural adhesion has not yet been elucidated. To elucidate the underlying mechanism of spinal pain generation by epidural adhesion using a two-dimensional (2D) non-linear finite element (FE) analysis. A finite element analysis. A two-dimensional nonlinear FE model of the herniated lumbar disc on L4/5 with epidural adhesion. A two-dimensional nonlinear FE model of the lumbar spine was developed, consisting of intervertebral discs, dura, spinal nerve, and lamina. The annulus fibrosus and nucleus pulpous were modeled as hyperelastic using the Mooney-Rivlin equation. The FE mesh was generated and analyzed using Abaqus (ABAQUS 6.13.; Hibbitt, Karlsson & Sorenson, Inc., Providence, RI, USA). Epidural adhesion was simulated as rough contact, in which no slip occurred once two surfaces were in contact, between the dura mater and posterior annulus fibrosus. The FE model of adhesion showed significant stress concentration in the spinal nerves, especially on the dorsal root ganglion (DRG). The stress concentration was caused by the lack of adaptive displacement between the dura mater and posterior annulus fibrosus. The peak von Mises stress was higher in the epidural adhesion model (Adhesion, 0.67 vs. Control, 0.46). In the control model, adaptive displacement was observed with decreased stress in the spinal nerve and DRG (with adhesion, 2.59 vs. without adhesion, 3.58, P < 0.00). This study used a 2D non-linear FE model, which simplifies the 3D nature of the human intervertebral disc. In addition, this 2D non-linear FE model has not yet been validated. The current study clearly demonstrated that epidural adhesion causes significantly increased stress in the spinal nerves, especially at the DRG. We believe that the increased stress on the spinal nerve might elicit more pain under similar magnitudes of lumbar disc protrusion.

Multidimensional Ultrasound Imaging of the Wrist: Changes of Shape and Displacement of the Median Nerve and Tendons in Carpal Tunnel Syndrome

PubMed Central

Filius, Anika; Scheltens, Marjan; Bosch, Hans G.; van Doorn, Pieter A.; Stam, Henk J.; Hovius, Steven E.R.; Amadio, Peter C.; Selles, Ruud W.

2015-01-01

Dynamics of structures within the carpal tunnel may alter in carpal tunnel syndrome (CTS) due to fibrotic changes and increased carpal tunnel pressure. Ultrasound can visualize these potential changes, making ultrasound potentially an accurate diagnostic tool. To study this, we imaged the carpal tunnel of 113 patients and 42 controls. CTS severity was classified according to validated clinical and nerve conduction study (NCS) classifications. Transversal and longitudinal displacement and shape (changes) were calculated for the median nerve, tendons and surrounding tissue. To predict diagnostic value binary logistic regression modeling was applied. Reduced longitudinal nerve displacement (p≤0.019), increased nerve cross-sectional area (p≤0.006) and perimeter (p≤0.007), and a trend of relatively changed tendon displacements were seen in patients. Changes were more convincing when CTS was classified as more severe. Binary logistic modeling to diagnose CTS using ultrasound showed a sensitivity of 70-71% and specificity of 80-84%. In conclusion, CTS patients have altered dynamics of structures within the carpal tunnel. PMID:25865180

Microsurgical resection of cauda equina schwannoma with nerve root preservation.

PubMed

McCormick, Paul C

2014-09-01

The occurrence of motor deficit following resection of an intradural spinal schwannoma is an uncommon but potentially serious complication. This video illustrates the technique of microsurgical resection of an L-4 sensory nerve root schwannoma with preservation of the corresponding functional L-4 motor nerve root. The video can be found here: http://youtu.be/HrZkGj1JKd4.

Effect of the gamma knife treatment on the trigeminal nerve root in Chinese patients with primary trigeminal neuralgia.

PubMed

Song, Zhi-Xiu; Qian, Wei; Wu, Yu-Quan; Sun, Fang-Jie; Fei, Jun; Huang, Run-Sheng; Fang, Jing-Yu; Wu, Cai-Zhen; An, You-Ming; Wang, Daxin; Yang, Jun

2014-01-01

To understand the mechanism of the gamma knife treating the trigeminal neuralgia. Using the MASEP-SRRS type gamma knife treatment system, 140 Chinese patients with trigeminal neuralgia (NT) were treated in our hospital from 2002 to 2010, in which the pain relief rate reached 95% and recurrence rate was 3% only. We investigated the effect of the gamma knife treatment on the trigeminal nerve root in 20 Chinese patients with primary trigeminal neuralgia by the magnetic resonance imager (MRI) observation. 1) The cross-sectional area of trigeminal nerve root became smaller and MRI signals were lower in the treatment side than those in the non-treatment side after the gamma knife treatment of primary trigeminal neuralgia; 2) in the treatment side, the cross-sectional area of the trigeminal nerve root decreased significantly after the gamma knife treatment; 3) there was good correlation between the clinical improvement and the MRI findings; and 4) the straight distance between the trigeminal nerve root and the brainstem did not change after the gamma knife treatment. The pain relief induced the gamma knife radiosurgery might be related with the atrophy of the trigeminal nerve root in Chinese patients with primary trigeminal neuralgia.

Massive nerve root enlargement in chronic inflammatory demyelinating polyneuropathy.

PubMed Central

Schady, W; Goulding, P J; Lecky, B R; King, R H; Smith, C M

1996-01-01

OBJECTIVE: To report three patients with chronic inflammatory demyelinating polyneuropathy (CIDP) presenting with symptoms suggestive of cervical (one patient) and lumbar root disease. METHODS: Nerve conduction studies, EMG, and nerve biopsy were carried out, having found the nerve roots to be very enlarged on MRI, CT myelography, and at surgery. RESULTS: Clinically, peripheral nerve thickening was slight or absent. Subsequently one patient developed facial nerve hypertrophy. This was mistaken for an inner ear tumour and biopsied, with consequent facial palsy. Neurophysiological tests suggested a demyelinating polyneuropathy. Sural nerve biopsy showed in all cases some loss of myelinated fibres, inflammatory cell infiltration, and a few onion bulbs. Hypertrophic changes were much more prominent on posterior nerve root biopsy in one patient: many fibres were surrounded by several layers of Schwann cell cytoplasm. There was an excellent response to steroids in two patients but not in the third (most advanced) patient, who has benefited only marginally from intravenous immunoglobulin therapy. CONCLUSIONS: MRI of the cauda equina may be a useful adjunct in the diagnosis of CIDP. Images PMID:8971116

Nerve crush but not displacement-induced stretch of the intra-arachnoidal facial nerve promotes facial palsy after cerebellopontine angle surgery.

PubMed

Bendella, Habib; Brackmann, Derald E; Goldbrunner, Roland; Angelov, Doychin N

2016-10-01

Little is known about the reasons for occurrence of facial nerve palsy after removal of cerebellopontine angle tumors. Since the intra-arachnoidal portion of the facial nerve is considered to be so vulnerable that even the slightest tension or pinch may result in ruptured axons, we tested whether a graded stretch or controlled crush would affect the postoperative motor performance of the facial (vibrissal) muscle in rats. Thirty Wistar rats, divided into five groups (one with intact controls and four with facial nerve lesions), were used. Under inhalation anesthesia, the occipital squama was opened, the cerebellum gently retracted to the left, and the intra-arachnoidal segment of the right facial nerve exposed. A mechanical displacement of the brainstem with 1 or 3 mm toward the midline or an electromagnet-controlled crush of the facial nerve with a tweezers at a closure velocity of 50 and 100 mm/s was applied. On the next day, whisking motor performance was determined by video-based motion analysis. Even the larger (with 3 mm) mechanical displacement of the brainstem had no harmful effect: The amplitude of the vibrissal whisks was in the normal range of 50°-60°. On the other hand, even the light nerve crush (50 mm/s) injured the facial nerve and resulted in paralyzed vibrissal muscles (amplitude of 10°-15°). We conclude that, contrary to the generally acknowledged assumptions, it is the nerve crush but not the displacement-induced stretching of the intra-arachnoidal facial trunk that promotes facial palsy after cerebellopontine angle surgery in rats.

Sciatica: Detection and Confirmation by New Method

PubMed Central

Nadkarni, Sunil

2014-01-01

We need to overcome limitations of present assessment and also integrate newer research in our work about sciatica. Inflammation induces changes in the DRG and nerve root. It sensitizes the axons. Nociceptor is a unique axon. It is pseudo unipolar: both its ends, central and peripheral, behave in similar fashion. The nerve in periphery which carries these axons may selectively become sensitive to mechanical pressure--“mechanosensitized,” as we coin the phrase. Many pain questionnaires are used and are effective in identifying neuropathic pain solely on basis of descriptors but they do not directly physically correlate nerve root and pain. A thorough neurological evaluation is always needed. Physical examination is not direct pain assessment but testing mobility of nerve root and its effect on pain generation. There is a dogmatic dominance of dermatomes in assessment of leg pain. They are unreliable. Images may not correlate with symptoms and pathology in about 28% of cases. Electrophysiology may be normal in purely inflamed nerve root. Palpation may help in such inflammatory setting to refine our assessment further. Confirmation of sciatica is done by selective nerve root block (SNRB) today but it is fraught with several complications and needs elaborate inpatient and operating room set up. We have used the unique property of the pseudo unipolar axon that both its ends have similar functional properties and so inject along its peripheral end sodium channel blockers to block the basic cause of the mechanosensitization namely upregulated sodium channels in the root or DRG. Thus using palpation we may be able to detect symptomatic nerve in stage of inflammation and with distal end injection, along same inflamed nerve we may be able to abolish and so confirm sciatica. Discussions of sciatica pain diagnosis tend to immediately shift and centre on the affected disc rather than the nerve. Theoretically it may be possible to detect the affected nerve by palpating the nerve and relieve pain moment we desensitize the nerve. PMID:25694916

Increased expression of CaV3.2 T-type calcium channels in damaged DRG neurons contributes to neuropathic pain in rats with spared nerve injury.

PubMed

Kang, Xue-Jing; Chi, Ye-Nan; Chen, Wen; Liu, Feng-Yu; Cui, Shuang; Liao, Fei-Fei; Cai, Jie; Wan, You

2018-01-01

Ion channels are very important in the peripheral sensitization in neuropathic pain. Our present study aims to investigate the possible contribution of Ca V 3.2 T-type calcium channels in damaged dorsal root ganglion neurons in neuropathic pain. We established a neuropathic pain model of rats with spared nerve injury. In these model rats, it was easy to distinguish damaged dorsal root ganglion neurons (of tibial nerve and common peroneal nerve) from intact dorsal root ganglion neurons (of sural nerves). Our results showed that Ca V 3.2 protein expression increased in medium-sized neurons from the damaged dorsal root ganglions but not in the intact ones. With whole cell patch clamp recording technique, it was found that after-depolarizing amplitudes of the damaged medium-sized dorsal root ganglion neurons increased significantly at membrane potentials of -85 mV and -95 mV. These results indicate a functional up-regulation of Ca V 3.2 T-type calcium channels in the damaged medium-sized neurons after spared nerve injury. Behaviorally, blockade of Ca V 3.2 with antisense oligodeoxynucleotides could significantly reverse mechanical allodynia. These results suggest that Ca V 3.2 T-type calcium channels in damaged medium-sized dorsal root ganglion neurons might contribute to neuropathic pain after peripheral nerve injury.

Spontaneous cerebrospinal fluid leak from an anomalous thoracic nerve root: case report.

PubMed

Lopez, Alejandro J; Campbell, Robert K; Arnaout, Omar; Curran, Yvonne M; Shaibani, Ali; Dahdaleh, Nader S

2016-12-01

The authors report the case of a 28-year-old woman with a spontaneous cerebrospinal fluid leak from the sleeve of a redundant thoracic nerve root. She presented with postural headaches and orthostatic symptoms indicative of intracranial hypotension. CT myelography revealed that the lesion was located at the T-11 nerve root. After failure of conservative management, including blood patches and thrombin glue injections, the patient was successfully treated with surgical decompression and ligation of the duplicate nerve, resulting in full resolution of her orthostatic symptoms.

T1 Radiculopathy: Electrodiagnostic Evaluation

PubMed Central

Radecki, Jeffrey; Zimmer, Zachary R.

2008-01-01

Electromyography (EMG) studies are useful in the anatomical localization of nerve injuries and, in most cases, isolating lesions to a single nerve root level. Their utility is important in identifying specific nerve-root-level injuries where surgical or interventional procedures may be warranted. In this case report, an individual presented with right upper extremity radicular symptoms consistent with a clinical diagnosis of cervical radiculopathy. EMG studies revealed that the lesion could be more specifically isolated to the T1 nerve root and, furthermore, provided evidence that the abductor pollicis brevis receives predominantly T1 innervation. PMID:19083061

Reinnervation of Urethral and Anal Sphincters With Femoral Motor Nerve to Pudendal Nerve Transfer

PubMed Central

Ruggieri, Michael R.; Braverman, Alan S.; Bernal, Raymond M.; Lamarre, Neil S.; Brown, Justin M.; Barbe, Mary F.

2012-01-01

Aims Lower motor neuron damage to sacral roots or nerves can result in incontinence and a flaccid urinary bladder. We showed bladder reinnervation after transfer of coccygeal to sacral ventral roots, and genitofemoral nerves (L1, 2 origin) to pelvic nerves. This study assesses the feasibility of urethral and anal sphincter reinnervation using transfer of motor branches of the femoral nerve (L2–4 origin) to pudendal nerves (S1, 2 origin) that innervate the urethral and anal sphincters in a canine model. Methods Sacral ventral roots were selected by their ability to stimulate bladder, urethral sphincter, and anal sphincter contraction and transected. Bilaterally, branches of the femoral nerve, specifically, nervus saphenous pars muscularis [Evans HE. Miller’s anatomy of the dog. Philadelphia: W.B. Saunders; 1993], were transferred and end-to-end anastomosed to transected pudendal nerve branches in the perineum, then enclosed in unipolar nerve cuff electrodes with leads to implanted RF micro-stimulators. Results Nerve stimulation induced increased anal and urethral sphincter pressures in five of six transferred nerves. Retrograde neurotracing from the bladder, urethral sphincter, and anal sphincter using fluorogold, fast blue, and fluororuby, demonstrated urethral and anal sphincter labeled neurons in L2–4 cord segments (but not S1–3) in nerve transfer canines, consistent with rein-nervation by the transferred femoral nerve motor branches. Controls had labeled neurons only in S1–3 segments. Postmortem DiI and DiO labeling confirmed axonal regrowth across the nerve repair site. Conclusions These results show spinal cord reinnervation of urethral and anal sphincter targets after sacral ventral root transection and femoral nerve transfer (NT) to the denervated pudendal nerve. These surgical procedures may allow patients to regain continence. PMID:21953679

Reduction in nerve root compression by the nucleus pulposus after Feng's Spinal Manipulation☆

PubMed Central

Feng, Yu; Gao, Yan; Yang, Wendong; Feng, Tianyou

2013-01-01

Ninety-four patients with lumbar intervertebral disc herniation were enrolled in this study. Of these, 48 were treated with Feng's Spinal Manipulation, hot fomentation, and bed rest (treatment group). The remaining 46 patients were treated with hot fomentation and bed rest only (control group). After 3 weeks of treatment, clinical parameters including the angle of straight-leg raising, visual analogue scale pain score, and Japanese Orthopaedic Association score for low back pain were improved. The treatment group had significantly better improvement in scores than the control group. Magnetic resonance myelography three-dimensional reconstruction imaging of the vertebral canal demonstrated that filling of the compressed nerve root sleeve with cerebrospinal fluid increased significantly in the treatment group. The diameter of the nerve root sleeve was significantly larger in the treatment group than in the control group. However, the sagittal diameter index of the herniated nucleus pulposus and the angle between the nerve root sleeve and the thecal sac did not change significantly in either the treatment or control groups. The effectiveness of Feng's Spinal Manipulation for the treatment of symptoms associated with lumbar intervertebral disc herniation may be attributable to the relief of nerve root compression, without affecting the herniated nucleus pulposus or changing the morphology or position of the nerve root. PMID:25206408

Radial nerve palsy in mid/distal humeral fractures: is early exploration effective?

PubMed

Keighley, Geffrey; Hermans, Deborah; Lawton, Vidya; Duckworth, David

2018-03-01

Radial nerve palsies are a common complication with displaced distal humeral fractures. This case series examines the outcomes of early operative exploration and decompression of the nerve with fracture fixation with the view that this provides a solid construct for optimisation of nerve recovery. A total of 10 consecutive patients with a displaced distal humeral fracture and an acute radial nerve palsy were treated by the senior author by open reduction and internal fixation of the distal humerus and exploration and decompression of the radial nerve. Motor function and sensation of the radial nerve was assessed in the post-operative period every 2 months or until full recovery of the radial nerve function had occurred. All patients (100%) had recovery of motor and sensation function of their upper limb in the radial nerve distribution over a 12-month period. Recovery times ranged between 4 and 32 weeks, with the median time to recovery occurring at 26 weeks and the average time to full recovery being 22.9 weeks. Wrist extension recovered by an average of 3 months (range 2-26 weeks) and then finger extension started to recover 2-6 weeks after this. Disability of the arm, shoulder and hand scores ranged from 0 to 11.8 at greater than 1 year post-operatively. Our study demonstrated that early operative exploration of the radial nerve when performing an open stabilization of displaced distal humeral fractures resulted in a 100% recovery of the radial nerve. © 2017 Royal Australasian College of Surgeons.

The Relation Between Rotation Deformity and Nerve Root Stress in Lumbar Scoliosis

NASA Astrophysics Data System (ADS)

Kim, Ho-Joong; Lee, Hwan-Mo; Moon, Seong-Hwan; Chun, Heoung-Jae; Kang, Kyoung-Tak

Even though several finite element models of lumbar spine were introduced, there has been no model including the neural structure. Therefore, the authors made the novel lumbar spine finite element model including neural structure. Using this model, we investigated the relation between the deformity pattern and nerve root stress. Two lumbar models with different types of curve pattern (lateral bending and lateral bending with rotation curve) were made. In the model of lateral bending curves without rotation, the principal compressive nerve root stress on the concave side was greater than the principal tensile stress on the convex side at the apex vertebra. Contrarily, in the lateral bending curve with rotational deformity, the nerve stress on the convex side was higher than that on the concave side. Therefore, this study elicit that deformity pattern could have significantly influence on the nerve root stress in the lumbar spine.

[Long-term effects of pulsed radiofrequency on the dorsal root ganglion and segmental nerve roots for lumbosacral radicular pain: a prospective controlled randomized trial with nerve root block].

PubMed

Fujii, Hiromi; Kosogabe, Yoshinori; Kajiki, Hideki

2012-08-01

Although pulsed radiofrequency (PRF) method for lumbosacral radicular pain (LSRP) is reportedly effective, there are no prospective controlled trials. We assessed the long-term efficacy of PRF of the dorsal root ganglion and nerve roots for LSRP as compared with nerve root block (RB). The study included 27 patients suffering from LSRP. The design of this study was randomized with a RB control. In the PRF group, the PRF current was applied for 120 seconds after RB. In the RB group, the patients received RB only. Visual analogue scale (VAS) was assessed immediately before, and immediately, 2 hours, 1 day, 1 week, 1 month, 3 months, 6 months, and 1 year after the procedure. P<0.05 was regarded as denoting statistical significance. In both groups, the VAS not only of short-term but also of long-term (6 months and 1 year after procedure) significantly decreased as compared with that before treatment (P<0.05). There were no significant differences of VAS between the two groups at the same time points. This study indicates that PRF adjacent to the dorsal root ganglion and nerve roots for LSRP has long-term effects. There were no significant differences of long-term effects between the two groups.

Measuring of the compensation of a nerve root in a cervical schwannoma: a case report.

PubMed

Saiki, Masahiko; Taguchi, Toshihiko; Kaneko, Kazuo; Toyota, Kouichiro; Kato, Yoshihiko; Li, Zhenglin; Kawai, Shinya

2003-01-01

A 64-year-old woman experienced numbness and hypesthesia of the right C6 dermatome a year ago. Enhanced magnetic resonance imaging of the cervical spine revealed an enhanced tumor continuing into the foramen from the spinal cord at the C5/6 intervertebral level. It was thought to be an Eden type 2 schwannoma. Right unilateral laminectomy was performed on C5. The tumor was present in the intradural area and arose from the right C6 anterior root. Compound muscle action potentials (CMAPs) from the deltoid, biceps, and extensor carpi radial (ECR) muscles were recorded following electric cervical nerve root stimulation (0.2 ms duration, and 7 mA intensity). CMAPs of large amplitude were obtained from the deltoid, biceps, and ECR muscles following C5 root stimulation, but those following C6 root stimulation were small. As a result it was determined that the right C6 root was not associated with the nerve distribution for these muscles, so it was resected en bloc with the tumor. No apparent loss of motor function was observed. Standard needle electromyography showed no denervation potentials or decrease in motor unit potentials in either the deltoid or biceps muscles. Intraoperative investigation for compensation of nerve root is clinically useful for determining whether resection of a nerve root results in muscle weakness after surgery for a cervical schwannoma.

New minimally invasive discectomy technique through the interlaminar space using a percutaneous endoscope.

PubMed

Dezawa, A; Sairyo, K

2011-05-01

The serial dilating technique used to access herniated discs at the L5-S1 space using percutaneous endoscopic discectomy (PED) via an 8 mm skin incision can possibly injure the S1 nerve root. In this paper, we describe in detail a new surgical procedure to safely access the disc and to avoid the nerve root damage. This small-incision endoscopic technique, small-incision microendoscopic discectomy (sMED), mimics microendoscopic discectomy and applies PED. The sMED approach is similar to the well-established microendoscopic discectomy technique. To secure the surgical field, a duckbill-type PED cannula is used. Following laminotomy of L5 using a high-speed drill, the ligamentum flavum is partially removed using the Kerrison rongeur. Using the curved nerve root retractor, the S1 nerve root is gradually and gently moved caudally. Following the compete retraction of the S1 nerve root to the caudal side of the herniated nucleus pulposus (HNP), the nerve root is retracted safely medially and caudally using the bill side of the duckbill PED cannula. Next, using the HNP rongeur for PED, the HNP is removed piece by piece until the nerve root is decompressed. A total of 30 patients with HNP at the L5-S1 level underwent sMED. In all cases, HNP was successfully removed and patients showed improvement following surgery. Only one patient complained of moderate radiculopathy at the final visit. No complications were encountered. We introduced a minimally invasive technique to safely remove HNP at the L5-S1 level. sMED is possibly the least invasive technique for HNP removal at the L5-S1 level. © 2011 Japan Society for Endoscopic Surgery, Asia Endosurgery Task Force and Blackwell Publishing Asia Pty Ltd.

Effects of ischemic phrenic nerve root ganglion injury on respiratory disturbances in subarachnoid hemorrhage: an experimental study.

PubMed

Ulvi, Hızır; Demir, Recep; Aygül, Recep; Kotan, Dilcan; Calik, Muhammet; Aydin, Mehmet Dumlu

2013-12-30

Phrenic nerves have important roles on the management of respiration rhythm. Diaphragm paralysis is possible in phrenic nerve roots ischemia in subarachnoid hemorrhage (SAH). We examined whether there is a relationship between phrenic nerve root ischemia and respiratory disturbances in SAH. This study was conducted on 5 healthy control and 14 rabbits with experimentally induced SAH by injecting autologous blood into their cisterna magna. Animals were followed up via monitors for detecting the heart and respiration rhythms for 20 days and then decapitaed by humanely. Normal and degenerated neuron densities of phrenic nerve root at the level of C4 dorsal root ganglia (C4DRG) were estimated by Stereological methods. Between the mean numerical density of degenerated neurons of C4DRG and respiratory rate/minute of groups were compared statistically. Phrenic nerve roots, artery and diaphragm muscles degeneration was detected in respiratory arrest developed animals. The mean neuronal density of C4DRG was 13272 ±1201/mm3 with a mean respiration rate of 23 ±4/min in the control group. The mean degenerated neuron density was 2.240 ±450/mm(3) and respiration rhythm was 31 ±6/min in survivors. But, the mean degenerated neuron density was 5850 ±650/mm(3) and mean respiration rhythm was 34 ±7/min in respiratory arrest developed animals (n = 7). A linear relationship was noticed between the degenerated neuron density of C4DRG and respiraton rate (r = -0.758; p < 0.001). Phrenic nerve root ischemia may be an important factor in respiration rhythms deteriorations in SAH which has not been mentioned in the literature.

Diagnostic value of history and physical examination in patients suspected of lumbosacral nerve root compression

PubMed Central

Vroomen, P; de Krom, M C T F M; Wilmink, J; Kester, A; Knottnerus, J

2002-01-01

Objective: To evaluate patient characteristics, symptoms, and examination findings in the clinical diagnosis of lumbosacral nerve root compression causing sciatica. Methods: The study involved 274 patients with pain radiating into the leg. All had a standardised clinical assessment and magnetic resonance (MR) imaging. The associations between patient characteristics, clinical findings, and lumbosacral nerve root compression on MR imaging were analysed. Results: Nerve root compression was associated with three patient characteristics, three symptoms, and four physical examination findings (paresis, absence of tendon reflexes, a positive straight leg raising test, and increased finger-floor distance). Multivariate analysis, analysing the independent diagnostic value of the tests, showed that nerve root compression was predicted by two patient characteristics, four symptoms, and two signs (increased finger-floor distance and paresis). The straight leg raise test was not predictive. The area under the curve of the receiver-operating characteristic was 0.80 for the history items. It increased to 0.83 when the physical examination items were added. Conclusions: Various clinical findings were found to be associated with nerve root compression on MR imaging. While this set of findings agrees well with those commonly used in daily practice, the tests tended to have lower sensitivity and specificity than previously reported. Stepwise multivariate analysis showed that most of the diagnostic information revealed by physical examination findings had already been revealed by the history items. PMID:11971050

Dual Nerve Transfers for Restoration of Shoulder Function After Brachial Plexus Avulsion Injury.

PubMed

Chu, Bin; Wang, Huan; Chen, Liang; Gu, Yudong; Hu, Shaonan

2016-06-01

The purpose of this study was to investigate the effectiveness of shoulder function restoration by dual nerve transfers, spinal accessory nerve to the suprascapular nerve and 2 intercostal nerves to the anterior branch of the axillary nerve, in patients with shoulder paralysis that resulted from brachial plexus avulsion injury. It was a retrospective analysis to assess the impact of a variety of factors on reanimation of shoulder functions with dual nerve transfers. A total of 19 patients were included in this study. Most of these patients sustained avulsions of C5, C6, and C7 nerve roots (16 patients). Three of them had avulsions of C5 and C6 roots only. Through a posterior approach, direct coaptation of the intercostal nerves and the anterior branch of the axillary nerve was performed, along with accessory nerve transfer to the suprascapular nerve. Satisfactory shoulder function recovery (93.83° of shoulder abduction and 54.00° of external rotation on average) was achieved after a 62-month follow-up. This dual nerve transfer procedure provided us with a reliable and effective method for shoulder function reconstruction after brachial plexus root avulsion, especially C5/C6/C7 avulsion. The level of evidence is therapeutic IV.

Pathophysiology, diagnosis and treatment of intermittent claudication in patients with lumbar canal stenosis.

PubMed

Kobayashi, Shigeru

2014-04-18

Spinal nerve roots have a peculiar structure, different from the arrangements in the peripheral nerve. The nerve roots are devoid of lymphatic vessels but are immersed in the cerebrospinal fluid (CSF) within the subarachnoid space. The blood supply of nerve roots depends on the blood flow from both peripheral direction (ascending) and the spinal cord direction (descending). There is no hypovascular region in the nerve root, although there exists a so-called water-shed of the bloodstream in the radicular artery itself. Increased mechanical compression promotes the disturbance of CSF flow, circulatory disturbance starting from the venous congestion and intraradicular edema formation resulting from the breakdown of the blood-nerve barrier. Although this edema may diffuse into CSF when the subarachnoid space is preserved, the endoneurial fluid pressure may increase when the area is closed by increased compression. On the other hand, the nerve root tissue has already degenerated under the compression and the numerous macrophages releasing various chemical mediators, aggravating radicular symptoms that appear in the area of Wallerian degeneration. Prostaglandin E1 (PGE1) is a potent vasodilator as well as an inhibitor of platelet aggregation and has therefore attracted interest as a therapeutic drug for lumbar canal stenosis. However, investigations in the clinical setting have shown that PGE1 is effective in some patients but not in others, although the reason for this is unclear.

Pathophysiology, diagnosis and treatment of intermittent claudication in patients with lumbar canal stenosis

PubMed Central

Kobayashi, Shigeru

2014-01-01

Spinal nerve roots have a peculiar structure, different from the arrangements in the peripheral nerve. The nerve roots are devoid of lymphatic vessels but are immersed in the cerebrospinal fluid (CSF) within the subarachnoid space. The blood supply of nerve roots depends on the blood flow from both peripheral direction (ascending) and the spinal cord direction (descending). There is no hypovascular region in the nerve root, although there exists a so-called water-shed of the bloodstream in the radicular artery itself. Increased mechanical compression promotes the disturbance of CSF flow, circulatory disturbance starting from the venous congestion and intraradicular edema formation resulting from the breakdown of the blood-nerve barrier. Although this edema may diffuse into CSF when the subarachnoid space is preserved, the endoneurial fluid pressure may increase when the area is closed by increased compression. On the other hand, the nerve root tissue has already degenerated under the compression and the numerous macrophages releasing various chemical mediators, aggravating radicular symptoms that appear in the area of Wallerian degeneration. Prostaglandin E1 (PGE1) is a potent vasodilator as well as an inhibitor of platelet aggregation and has therefore attracted interest as a therapeutic drug for lumbar canal stenosis. However, investigations in the clinical setting have shown that PGE1 is effective in some patients but not in others, although the reason for this is unclear. PMID:24829876

Intraoperative conjoined lumbosacral nerve roots associated with spondylolisthesis.

PubMed

Popa, Iulian; Poenaru, Dan V; Oprea, Manuel D; Andrei, Diana

2013-07-01

Lumbosacral nerve roots anomalies may produce low back pain. These anomalies are reported to be a cause for failed back surgery. They are usually left undiagnosed, especially in endoscopic discectomy techniques. Any surgery for entrapment disorders, performed on a patient with undiagnosed lumbosacral nerve roots anomaly, may lead to serious neural injuries because of an improper surgical technique or decompression. In this report, we describe our experience with a case of L5-S1 spondylolisthesis and associated congenital lumbosacral nerve root anomalies discovered during the surgical intervention, and the difficulties raised by such a discovery. Careful examination of coronal and axial views obtained through high-quality Magnetic Resonance Imaging may lead to a proper diagnosis of this condition leading to an adequate surgical planning, minimizing the intraoperatory complications.

Virtual pathology of cervical radiculopathy based on 3D MR/CT fusion images: impingement, flattening or twisted condition of the compressed nerve root in three cases.

PubMed

Kamogawa, Junji; Kato, Osamu; Morizane, Tatsunori; Hato, Taizo

2015-01-01

There have been several imaging studies of cervical radiculopathy, but no three-dimensional (3D) images have shown the path, position, and pathological changes of the cervical nerve roots and spinal root ganglion relative to the cervical bony structure. The objective of this study was to introduce a technique that enables the virtual pathology of the nerve root to be assessed using 3D magnetic resonance (MR)/computed tomography (CT) fusion images that show the compression of the proximal portion of the cervical nerve root by both the herniated disc and the preforaminal or foraminal bony spur in patients with cervical radiculopathy. MR and CT images were obtained from three patients with cervical radiculopathy. 3D MR images were placed onto 3D CT images using a computer workstation. The entire nerve root could be visualized in 3D with or without the vertebrae. The most important characteristic evident on the images was flattening of the nerve root by a bony spur. The affected root was constricted at a pre-ganglion site. In cases of severe deformity, the flattened portion of the root seemed to change the angle of its path, resulting in twisted condition. The 3D MR/CT fusion imaging technique enhances visualization of pathoanatomy in cervical hidden area that is composed of the root and intervertebral foramen. This technique provides two distinct advantages for diagnosis of cervical radiculopathy. First, the isolation of individual vertebra clarifies the deformities of the whole root groove, including both the uncinate process and superior articular process in the cervical spine. Second, the tortuous or twisted condition of a compressed root can be visualized. The surgeon can identify the narrowest face of the root if they view the MR/CT fusion image from the posterolateral-inferior direction. Surgeons use MR/CT fusion images as a pre-operative map and for intraoperative navigation. The MR/CT fusion images can also be used as educational materials for all hospital staff and for patients and patients' families who provide informed consent for treatments.

Development of Kinematic Graphs of Median Nerve during Active Finger Motion: Implications of Smartphone Use

PubMed Central

2016-01-01

Background Certain hand activities cause deformation and displacement of the median nerve at the carpal tunnel due to the gliding motion of tendons surrounding it. As smartphone usage escalates, this raises the public’s concern whether hand activities while using smartphones can lead to median nerve problems. Objective The aims of this study were to 1) develop kinematic graphs and 2) investigate the associated deformation and rotational information of median nerve in the carpal tunnel during hand activities. Methods Dominant wrists of 30 young adults were examined with ultrasonography by placing a transducer transversely on their wrist crease. Ultrasound video clips were recorded when the subject performing 1) thumb opposition with the wrist in neutral position, 2) thumb opposition with the wrist in ulnar deviation and 3) pinch grip with the wrist in neutral position. Six still images that were separated by 0.2-second intervals were then captured from the ultrasound video for the determination of 1) cross-sectional area (CSA), 2) flattening ratio (FR), 3) rotational displacement (RD) and 4) translational displacement (TD) of median nerve in the carpal tunnel, and these collected information of deformation, rotational and displacement of median nerve were compared between 1) two successive time points during a single hand activity and 2) different hand motions at the same time point. Finally, kinematic graphs were constructed to demonstrate the mobility of median nerve during different hand activities. Results Performing different hand activities during this study led to a gradual reduction in CSA of the median nerve, with thumb opposition together with the wrist in ulnar deviation causing the greatest extent of deformation of the median nerve. Thumb opposition with the wrist in ulnar deviation also led to the largest extent of TD when compared to the other two hand activities of this study. Kinematic graphs showed that the motion pathways of median nerve during different hand activities were complex. Conclusion We observed that the median nerve in the carpal tunnel was rotated, deformed and displaced during the hand activities that people may be performed when using a smartphone, suggesting an increased risk of carpal tunnel syndrome (CTS). In addition, the kinematic graphs of median nerve developed in the present study provide new clues for further studies on the pathophysiology of CTS, and alerting smartphone users to establish proper postural habits when using handheld electronic devices. PMID:27367447

Ligament, nerve, and blood vessel anatomy of the lateral zone of the lumbar intervertebral foramina.

PubMed

Yuan, Shi-Guo; Wen, You-Liang; Zhang, Pei; Li, Yi-Kai

2015-11-01

To provide an anatomical basis for intrusive treatment using an approach through the lateral zones of the lumbar intervertebral foramina (LIF), especially for acupotomology lysis, percutaneous transforaminal endoscopy, and lumbar nerve root block. Blood vessels, ligaments, nerves, and adjacent structures of ten cadavers were exposed through the L1-2 to L5-S1 intervertebral foramina and examined. The lateral zones of the LIF were almost filled by ligaments, nerves, and blood vessels, which were separated into compartments by superior/inferior transforaminal ligaments and corporotransverse superior/inferior ligaments. Two zones relatively lacking in blood vessels and nerves (triangular working zones) were found beside the lamina of the vertebral arch and on the root of the transverse processus. Both the ascending lumbar vein and branches of the intervetebral vein were observed in 12 Kambin's triangles, and in only seven Kambin's triangles were without any veins. Nerves and blood vessels are fixed and protected by transforaminal ligaments and/or corporotransverse ligaments. It is necessary to distinguish the ligaments from nerves using transforaminal endoscopy so that the ligaments can be cut without damaging nerves. Care needs to be taken in intrusive operations because of the veins running through Kambin's triangle. We recommend injecting into the lamina of the vertebral arch and the midpoint between the adjacent roots of the transverse processus when administering nerve root block. Blind percutaneous incision and acupotomology lysis is dangerous in the lateral zones of the LIF, as they are filled with nerves and blood vessels.

Characterization of a chondroitin sulfate hydrogel for nerve root regeneration

NASA Astrophysics Data System (ADS)

Conovaloff, Aaron; Panitch, Alyssa

2011-10-01

Brachial plexus injury is a serious medical problem that affects many patients annually, with most cases involving damage to the nerve roots. Therefore, a chondroitin sulfate hydrogel was designed to both serve as a scaffold for regenerating root neurons and deliver neurotrophic signals. Capillary electrophoresis showed that chondroitin sulfate has a dissociation constant in the micromolar range with several common neurotrophins, and this was determined to be approximately tenfold stronger than with heparin. It was also revealed that nerve growth factor exhibits a slightly stronger affinity for hyaluronic acid than for chondroitin sulfate. However, E8 chick dorsal root ganglia cultured in the presence of nerve growth factor revealed that ganglia cultured in chondroitin sulfate scaffolds showed more robust growth than those cultured in control gels of hyaluronic acid. It is hypothesized that, despite the stronger affinity of nerve growth factor for hyaluronic acid, chondroitin sulfate serves as a better scaffold for neurite outgrowth, possibly due to inhibition of growth by hyaluronic acid chains.

[The phrenic nerve in the guinea pig (Cavia porcellus L. 1756)].

PubMed

Salgado, M C; Orsi, A M; Vicentini, C A; Mello Dias, S

1983-01-01

The aim of the present study was the ascertain in the mode of origin of the phrenic nerve and to provide a morphological basis for experimental studies of this nerve in the guinea pig. In sketches made of the dissections, in 10 male and 10 female guinea pigs adults, the modes of origin of the phrenic roots were demonstrated to arise from the fourth to the seventh cervical nerves. Four types of origin could be distinguished. The phrenic nerve of guinea pig has three or four roots.

The Accuracy of the Physical Examination for the Diagnosis of Midlumbar and Low Lumbar Nerve Root Impingement

PubMed Central

Suri, Pradeep; Rainville, James; Katz, Jeffrey N.; Jouve, Cristin; Hartigan, Carol; Limke, Janet; Pena, Enrique; Li, Ling; Swaim, Bryan; Hunter, David J

2010-01-01

Study Design Cross-sectional study with prospective recruitment. Objective To determine the accuracy of the physical examination for the diagnosis of midlumbar nerve root impingement (L2, L3, or L4), low lumbar nerve root impingement (L5 or S1) and level-specific lumbar nerve root impingement on magnetic resonance imaging (MRI), using individual tests and combinations of tests. Summary of Background Data The sensitivity and specificity of the physical examination for the localization of nerve root impingement has not been previously studied. Methods Sensitivities, specificities and LRs were calculated for the ability of individual tests and test combinations to predict the presence or absence of nerve root impingement at midlumbar, low lumbar, and specific nerve root levels. Results LRs ≥5.0 indicate moderate to large changes from pre-test probability of nerve root impingement to post-test probability. For the diagnosis of midlumbar impingement, the femoral stretch test (FST), crossed femoral stretch test (CFST), medial ankle pinprick sensation, and patellar reflex testing demonstrated LRs ≥5.0 (LR ∞). LRs ≥5.0 were seen with the combinations of FST and either patellar reflex testing (LR 7.0; 95% CI 2.3–21), or the sit-to-stand test (LR ∞). For the diagnosis of low lumbar impingement, the Achilles reflex test demonstrated a LR ≥5.0 (LR 7.1; CI 0.96–53); test combinations did not increase LRs. For the diagnosis of level-specific impingement, LRs ≥5.0 were seen for anterior thigh sensation at L2 (LR 13; 95% CI 1.8–87); FST at L3 (LR 5.7 ; 95% CI 2.3–4.4); patellar reflex testing (LR 7.7; 95% CI 1.7–35), medial ankle sensation (LR ∞), or CFST (LR 13; 95% CI 1.8–87) at L4; and hip abductor strength at L5(LR 11; 95% CI 1.3–84). Test combinations increased LRs for level-specific root impingement at the L4 level only. Conclusions Individual physical examination tests may provide clinical information which substantially alters the likelihood that midlumbar impingement, low lumbar impingement, or level-specific impingement is present. Test combinations improve diagnostic accuracy for midlumbar impingement. PMID:20543768

Evaluation of lumbar transforaminal epidural injections with needle placement and contrast flow patterns: a prospective, descriptive report.

PubMed

Manchikanti, Laxmaiah; Cash, Kim A; Pampati, Vidyasagar; Damron, Kim S; McManus, Carla D

2004-04-01

Transforaminal epidural steroid injection is one of the commonly employed modalities of treatment in managing nerve root pain. However, there have been no controlled prospective evaluations of epidural and nerve root contrast distribution patterns and other aspects of fluoroscopically directed lumbosacral transforaminal epidural steroid injections. To evaluate contrast flow patterns and intravascular needle placement of fluoroscopically guided lumbosacral transforaminal epidural injections. A prospective, observational study. A total of 100 consecutive patients undergoing fluoroscopically guided transforaminal epidural steroid injections were evaluated. The contrast flow patterns, ventral or dorsal epidural filling, nerve root filling, C-arm time, and intravascular needle placement were evaluated. Ventral epidural filling was seen in 88% of the procedures, in contrast to dorsal filling noted in 9% of the procedures. Nerve root filling was seen in 97% of the procedures. Total intravenous placement of the needle was noted in 22% of the procedures, whereas negative flashback and aspiration was noted in 5% of the procedures. Lumbosacral transforaminal epidural injections, performed under fluoroscopic visualization, provide excellent nerve root filling and ventral epidural filling patterns. However, unrecognized intravascular needle placement with negative flashback or aspiration was noted in 5% of the procedures.

The anatomical relationship between the roots of mandibular second molars and the inferior alveolar nerve.

PubMed

Chong, B S; Quinn, A; Pawar, R R; Makdissi, J; Sidhu, S K

2015-06-01

To evaluate the anatomical relationship between the roots of mandibular second molars and the inferior alveolar nerve (IAN) in relation to the risk of potential nerve injury during root canal treatment. Cone-beam computed tomography (CBCT) images from the patient record database at a dental hospital were selected. The anonymized CBCT images were reconstructed and examined in three planes (coronal, axial and sagittal) using 3D viewing software. The relationship between each root apex of mandibular second molars and the IAN was evaluated by measuring the horizontal and vertical distances from coronal CBCT sections, and the actual distance was then calculated mathematically using Pythagoras' theorem. In 55% of the 272 mandibular second molar roots evaluated, from a total of 134 scans, the distance between the anatomical root apex and the IAN was ≤3 mm. In over 50% of the cases evaluated, there was an intimate relationship between the roots of mandibular second molars and the inferior alveolar nerve (IAN). Therefore, root canal treatment of mandibular second molars may pose a more significant potential risk of IAN injury; necessary precautions should be exercised, and the prudent use of CBCT should be considered if an intimate relationship is suspected. © 2014 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Professional driving and prolapsed lumbar intervertebral disc diagnosed by magnetic resonance imaging – a case–control study

PubMed Central

Palmer, Keith T; Griffin, Michael; Ntani, Georgia; Shambrook, James; McNee, Philip; Sampson, Madeleine; Harris, E Clare; Coggon, David

2012-01-01

Objectives The aim of this study was to investigate whether whole-body vibration (WBV) is associated with prolapsed lumbar intervertebral disc (PID) and nerve root entrapment among patients with low-back pain (LBP) undergoing magnetic resonance imaging (MRI). Methods A consecutive series of patients referred for lumbar MRI because of LBP were compared with controls X-rayed for other reasons. Subjects were questioned about occupational activities loading the spine, psychosocial factors, driving, personal characteristics, mental health, and certain beliefs about LBP. Exposure to WBV was assessed by six measures, including weekly duration of professional driving, hours driven at a spell, and current 8-hour daily equivalent root-mean-square acceleration A(8). Cases were sub-classified according to whether or not PID/nerve root entrapment was present. Associations with WBV were examined separately for cases with and without these MRI findings, with adjustment for age, sex, and other potential confounders. Results Altogether, 237 cases and 820 controls were studied, including 183 professional drivers and 176 cases with PID and/or nerve root entrapment. Risks associated with WBV tended to be lower for LBP with PID/nerve root entrapment but somewhat higher for risks of LBP without these abnormalities. However, associations with the six metrics of exposure were all weak and not statistically significant. Neither exposure–response relationships nor increased risk of PID/nerve root entrapment from professional driving or exposure at an A(8) above the European Union daily exposure action level were found. Conclusions WBV may be a cause of LBP but it was not associated with PID or nerve root entrapment in this study. PMID:22249859

Analysis of radiological parameters associated with decreased fractional anisotropy values on diffusion tensor imaging in patients with lumbar spinal stenosis.

PubMed

Wang, Xiandi; Wang, Hongli; Sun, Chi; Zhou, Shuyi; Meng, Tao; Lv, Feizhou; Ma, Xiaosheng; Xia, Xinlei; Jiang, Jianyuan

2018-04-26

Previous studies have indicated that decreased fractional anisotropy (FA) values on diffusion tensor imaging (DTI) are well correlated with the symptoms of nerve root compression. The aim of our study is to determine primary radiological parameters associated with decreased FA values in patients with lumbar spinal stenosis involving single L5 nerve root. Patients confirmed with single L5 nerve root compression by transforaminal nerve root blocks were included in this study. FA values of L5 nerve roots on both symptomatic and asymptomatic side were obtained. Conventional radiological parameters, such as disc height, degenerative scoliosis, dural sac cross-sectional area (DSCSA), foraminal height (FH), hypertrophic facet joint degeneration (HFJD), sagittal rotation (SR), sedimentation sign, sagittal translation and traction spur were measured. Correlation and regression analyses were performed between the radiological parameters and FA values of the symptomatic L5 nerve roots. A predictive regression equation was established. Twenty-one patients were included in this study. FA values were significantly lower at the symptomatic side comparing to the asymptomatic side (0.263 ± 0.069 vs. 0.334 ± 0.080, P = 0.038). DSCSA, FH, HFJD, and SR were significantly correlated with the decreased FA values, with r = 0.518, 0.443, 0.472 and - 0.910, respectively (P < 0.05). DSCSA and SR were found to be the primary radiological parameters related to the decreased FA values, and the regression equation is FA = - 0.012 × SR + 0.002 × DSCSA. DSCSA and SR were primary contributors to decreased FA values in LSS patients involving single L5 nerve root, indicating that central canal decompression and segmental stability should be the first considerations in preoperative planning of these patients. These slides can be retrieved under Electronic Supplementary Material.

A novel chondroitin sulfate hydrogel for nerve repair

NASA Astrophysics Data System (ADS)

Conovaloff, Aaron William

Brachial plexus injuries affect numerous patients every year, with very debilitating results. The majority of these cases are very severe, and involve damage to the nerve roots. To date, repair strategies for these injuries address only gross tissue damage, but do not supply cells with adequate regeneration signals. As a result, functional recovery is often severely lacking. Therefore, a chondroitin sulfate hydrogel that delivers neurotrophic signals to damaged neurons is proposed as a scaffold to support nerve root regeneration. Capillary electrophoresis studies revealed that chondroitin sulfate can physically bind with a variety of neurotrophic factors, and cultures of chick dorsal root ganglia demonstrated robust neurite outgrowth in chondroitin sulfate hydrogels. Outgrowth in chondroitin sulfate gels was greater than that observed in control gels of hyaluronic acid. Furthermore, the chondroitin sulfate hydrogel's binding activity with nerve growth factor could be enhanced by incorporation of a synthetic bioactive peptide, as revealed by fluorescence recovery after photobleaching. This enhanced binding was observed only in chondroitin sulfate gels, and not in hyaluronic acid control gels. This enhanced binding activity resulted in enhanced dorsal root ganglion neurite outgrowth in chondroitin sulfate gels. Finally, the growth of regenerating dorsal root ganglia in these gels was imaged using label-free coherent anti-Stokes scattering microscopy. This technique generated detailed, high-quality images of live dorsal root ganglion neurites, which were comparable to fixed, F-actin-stained samples. Taken together, these results demonstrate the viability of this chondroitin sulfate hydrogel to serve as an effective implantable scaffold to aid in nerve root regeneration.

More nerve root injuries occur with minimally invasive lumbar surgery, especially extreme lateral interbody fusion: A review

PubMed Central

Epstein, Nancy E.

2016-01-01

Background: In the lumbar spine, do more nerve root injuries occur utilizing minimally invasive surgery (MIS) techniques versus open lumbar procedures? To answer this question, we compared the frequency of nerve root injuries for multiple open versus MIS operations including diskectomy, laminectomy with/without fusion addressing degenerative disc disease, stenosis, and/or degenerative spondylolisthesis. Methods: Several of Desai et al. large Spine Patient Outcomes Research Trial studies showed the frequency for nerve root injury following an open diskectomy ranged from 0.13% to 0.25%, for open laminectomy/stenosis with/without fusion it was 0%, and for open laminectomy/stenosis/degenerative spondylolisthesis with/without fusion it was 2%. Results: Alternatively, one study compared the incidence of root injuries utilizing MIS transforaminal lumbar interbody fusion (TLIF) versus posterior lumbar interbody fusion (PLIF) techniques; 7.8% of PLIF versus 2% of TLIF patients sustained root injuries. Furthermore, even higher frequencies of radiculitis and nerve root injuries occurred during anterior lumbar interbody fusions (ALIFs) versus extreme lateral interbody fusions (XLIFs). These high frequencies were far from acceptable; 15.8% following ALIF experienced postoperative radiculitis, while 23.8% undergoing XLIF sustained root/plexus deficits. Conclusions: This review indicates that MIS (TLIF/PLIF/ALIF/XLIF) lumbar surgery resulted in a higher incidence of root injuries, radiculitis, or plexopathy versus open lumbar surgical techniques. Furthermore, even a cursory look at the XLIF data demonstrated the greater danger posed to neural tissue by this newest addition to the MIS lumbar surgical armamentariu. The latter should prompt us as spine surgeons to question why the XLIF procedure is still being offered to our patients? PMID:26904372

Computed tomography of cystic nerve root sleeve dilatation.

PubMed

Neave, V C; Wycoff, R R

1983-10-01

A case of cystic nerve root sleeve dilatation in the lumbar area associated with a chronic back pain syndrome is presented. Prominent computed tomography (CT) findings include: (a) rounded masses in the region of the foramina isodense with cerebrospinal fluid in the subarachnoid space; (b) associated asymmetry of epidural fat distribution; (c) enlargement of the neural foramina in axial sections with scalloped erosion of the adjacent posteriolateral vertebral body, pedicle, and pedicular-laminar junction with preservation of cortex and without bony sclerosis or infiltrative appearance; (d) prominent or ectatic dural sac with lack of usual epidural landmarks between the sac and vertebral body; and (e) multilevel abnormalities throughout the entire lumbar region. Myelographic and CT correlations are demonstrated with a review of the literature. A discussion of the various cystic abnormalities involving nerve root sheaths is undertaken in an attempt to clarify the confusing nomenclature applied to nerve root sleeve pathology.

Coronectomy of third molar: a reduced risk technique for inferior alveolar nerve damage.

PubMed

Ahmed, Chkoura; Wafae, El Wady; Bouchra, Taleb

2011-05-01

Causing damage to the inferior alveolar nerve (IAN) when extracting lower third molars is due to the intimate relationship between the nerve and the roots of the teeth. When the proximity radiologic markers between the IAN and the root of the third molars are present, the technique of coronectomy can be proposed as an alternative to extraction to minimize the risk of nerve injury, with minimal complications. Nerve injury after the extraction of the mandibular third molar is a serious complication. The technique of coronectomy can be proposed to minimize the risk.

New technique targeting the C5 nerve root proximal to the traditional interscalene sonoanatomical approach is analgesic for outpatient arthroscopic shoulder surgery.

PubMed

Dobie, Katherine H; Shi, Yaping; Shotwell, Matthew S; Sandberg, Warren S

2016-11-01

Regional anesthesia and analgesia for shoulder surgery is most commonly performed via interscalene nerve block. We developed an ultrasound-guided technique that specifically targets the C5 nerve root proximal to the traditional interscalene block and assessed its efficacy for shoulder analgesia. Prospective case series. Vanderbilt Bone and Joint Surgery Center. Patients undergoing shoulder arthroscopy at an ambulatory surgery center. Thirty-five outpatient shoulder arthroscopy patients underwent an analgesic nerve block using a new technique where ultrasound visualization of the C5 nerve root served as the primary target at a level proximal to the traditional interscalene approach. The block was performed with 15mL of 0.5% plain ropivicaine. Post anesthesia care unit pain scores, opioid consumption, hand strength, and duration of block were recorded. Cadaver dissection after injection with methylene blue confirmed that the primary target under ultrasound visualization was the C5 nerve root. Pain scores revealed 97% patients had 0/10 pain at arrival to PACU, with 91% having a pain score of 3/10 or less at discharge from PACU. Medical Research Council (MRC) hand strength mean (SD) score was 4.17 (0.92) on a scale of 1-5. The mean (SD) duration of the block was 13.9 (3.5) hours. A new technique for ultrasound-guided blockade at the level of the C5 nerve root proximal to the level of the traditional interscalene block is efficacious for shoulder post-operative pain control. Copyright © 2016 Elsevier Inc. All rights reserved.

Patterns of motor activity in the isolated nerve cord of the octopus arm.

PubMed

Gutfreund, Yoram; Matzner, Henry; Flash, Tamar; Hochner, Binyamin

2006-12-01

The extremely flexible octopus arm provides a unique opportunity for studying movement control in a highly redundant motor system. We describe a novel preparation that allows analysis of the peripheral nervous system of the octopus arm and its interaction with the muscular and mechanosensory elements of the arm's intrinsic muscular system. First we examined the synaptic responses in muscle fibers to identify the motor pathways from the axial nerve cord of the arm to the surrounding musculature. We show that the motor axons project to the muscles via nerve roots originating laterally from the arm nerve cord. The motor field of each nerve is limited to the region where the nerve enters the arm musculature. The same roots also carry afferent mechanosensory information from the intrinsic muscle to the axial nerve cord. Next, we characterized the pattern of activity generated in the dorsal roots by electrically stimulating the axial nerve cord. The evoked activity, although far reaching and long lasting, cannot alone account for the arm extension movements generated by similar electrical stimulation. The mismatch between patterns of activity in the isolated cord and in an intact arm may stem from the involvement of mechanosensory feedback in natural arm extension.

Postoperative occipital neuralgia with and without C2 nerve root transection during atlantoaxial screw fixation: a post-hoc comparative outcome study of prospectively collected data.

PubMed

Yeom, Jin S; Buchowski, Jacob M; Kim, Ho-Joong; Chang, Bong-Soon; Lee, Choon-Ki; Riew, K Daniel

2013-07-01

Although routine transection of the C2 nerve root during atlantoaxial segmental screw fixation has been recommended by some surgeons, it remains controversial and to our knowledge no comparative studies have been performed to determine whether transection or preservation of the C2 nerve root affects patient-derived sensory outcomes. The purpose of this study is to specifically analyze patient-derived sensory outcomes over time in patients with intentional C2 nerve root transection during atlantoaxial segmental screw fixation compared with those without transection. This is a post-hoc comparative analysis of prospectively collected patient-derived outcome data. The sample consists of 24 consecutive patients who underwent intentional bilateral transection of the C2 nerve root during posterior atlantoaxial segmental screw fixation (transection group) and subsequent 41 consecutive patients without transection (preservation group). A visual analog scale (VAS) score was used for occipital neuralgia as the primary outcome measure and VAS score for neck pain, neck disability index score and Japanese Orthopedic Association score for cervical myelopathy and recovery rate, with bone union rate as the secondary outcome measure. Patient-derived outcomes including change in VAS score for occipital neuralgia over time were statistically compared between the two groups. This study was not supported by any financial sources and there is no topic-specific conflict of interest related to the authors of this study. Seven (29%) of the 24 patients in the transection group experienced increased neuralgic pain at 1 month after surgery either because of newly developed occipital neuralgia or aggravation of preexisting occipital neuralgia. Four of the seven patients required almost daily medication even at the final follow-up (44 and 80 months). On the other hand, only four (10%) of 41 patients in the preservation group had increased neuralgic pain at 1 month after surgery, and at ≥ 1 year, no patients had increased neuralgic pain. The difference in the prevalence of increased neuralgic pain between the two groups was statistically significant at all time points (3, 6, 12, and 24 months postoperatively) except at 1 month postoperatively. The intensity of neuralgic pain, which preoperatively had not been significantly different between the two groups, was significantly higher in the transection group at the final follow-up. C2 nerve root transection is not a benign procedure and, in our experience, more than a quarter of the patients experience increased neuralgic pain following C2 nerve root transection. Because the prevalence and intensity of postoperative neuralgia was significantly higher with C2 nerve root transection than with its preservation, we recommend against routine C2 nerve root transection when performing atlantoaxial segmental screw fixation. Copyright © 2013 Elsevier Inc. All rights reserved.

Methodology and preliminary results of evaluating stem displacement and assessing root system architecture of longleaf pine saplings

Treesearch

Shi-Jean S. Sung; Daniel J. Leduc; James D. Haywood; Thomas L. Eberhardt; Mary Anne Sword Sayer; Stanley J. Zarnoch

2012-01-01

A field experiment of the effects of container cavity size and root pruning type on longleaf pine was established in November, 2004, in central Louisiana. Sapling stems were first observed to be leaning after hurricane Gustav (September, 2008) and again in August, 2009. To examine the relationship between stem displacement and root system architecture, a stem-displaced...

[Paresthesia and spinal anesthesia for cesarean section: comparison of patient positioning].

PubMed

Palacio Abizanda, F J; Reina, M A; Fornet, I; López, A; López López, M A; Morillas Sendín, P

2009-01-01

To determine the incidence of paresthesia during lumbar puncture performed with the patient in different positions. A single-blind prospective study of patients scheduled for elective cesarean section, randomized to 3 groups. In group 1 patients were seated in the direction of the long axis of the table, with heels resting on the table. In group 2 they were seated perpendicular to the long axis of the table, with legs hanging from the table. In group 3 they were in left lateral decubitus position. Lumbar punctures were performed with a 27-gauge Whitacre needle. One hundred sixty-eight patients (56 per group) were enrolled. Paresthesia occurred most often in group 3 (P = .009). We observed no differences in blood pressure after patients moved from decubitus position to the assigned position. Nor did we observe between-group differences in blood pressure according to position taken during puncture. Puncture undertaken with the patient seated, heels on the table and knees slightly bent, is associated with a lower incidence of paresthesia than puncture performed with the patient seated, legs hanging from the table. Placing the patient's heels on the table requires hip flexion and leads to anterior displacement of nerve roots in the dural sac. Such displacement would increase the nerve-free zone on the posterior side of the sac, thereby decreasing the likelihood of paresthesia during lumbar puncture. A left lateral decubitus position would increase the likelihood of paresthesia, possibly because the anesthetist may inadvertently not follow the medial line when inserting the needle.

Rectal sphincter pressure monitoring device.

PubMed

Hellbusch, L C; Nihsen, B J

1989-05-01

A silicone, dual cuffed catheter designed for the control of nasal hemorrhage was used for rectal sphincter pressure monitoring. Patients with lipomyelomeningocele and tethered spinal cord were monitored during their operative procedures to aid in distinguishing sacral nerve roots from other tissues. Stimulation of sacral nerve roots was done with a disposable nerve stimulator. The use of a catheter with two balloons helps to keep the outer balloon placed against the rectal sphincter.

Differentiation between Symptomatic and Asymptomatic Extraforaminal Stenosis in Lumbosacral Transitional Vertebra: Role of Three-Dimensional Magnetic Resonance Lumbosacral Radiculography

PubMed Central

Kim, Jae Woon; Lee, Jae Kyo

2012-01-01

Objective To investigate the role of lumbosacral radiculography using 3-dimentional (3D) magnetic resonance (MR) rendering for diagnostic information of symptomatic extraforaminal stenosis in lumbosacral transitional vertebra. Materials and Methods The study population consisted of 18 patients with symptomatic (n = 10) and asymptomatic extraforaminal stenosis (n = 8) in lumbosacral transitional vertebra. Each patient underwent 3D coronal fast-field echo sequences with selective water excitation using the principles of the selective excitation technique (Proset imaging). Morphologic changes of the L5 nerve roots at the symptomatic and asymptomatic extraforaminal stenosis were evaluated on 3D MR rendered images of the lumbosacral spine. Results Ten cases with symptomatic extraforaminal stenosis showed hyperplasia and degenerative osteophytes of the sacral ala and/or osteophytes at the lateral margin of the L5 body. On 3D MR lumbosacral radiculography, indentation of the L5 nerve roots was found in two cases, while swelling of the nerve roots was seen in eight cases at the exiting nerve root. Eight cases with asymptomatic extraforaminal stenosis showed hyperplasia and degenerative osteophytes of the sacral ala and/or osteophytes at the lateral margin of the L5 body. Based on 3D MR lumbosacral radiculography, indentation or swelling of the L5 nerve roots was not found in any cases with asymptomatic extraforaminal stenosis. Conclusion Results from 3D MR lumbosacral radiculography Indicate the indentation or swelling of the L5 nerve root in symptomatic extraforaminal stenosis. Based on these findings, 3D MR radiculography may be helpful in the diagnosis of the symptomatic extraforaminal stenosis with lumbosacral transitional vertebra. PMID:22778561

Ultrasound-guided approach for axillary brachial plexus, femoral nerve, and sciatic nerve blocks in dogs.

PubMed

Campoy, Luis; Bezuidenhout, Abraham J; Gleed, Robin D; Martin-Flores, Manuel; Raw, Robert M; Santare, Carrie L; Jay, Ariane R; Wang, Annie L

2010-03-01

To describe an ultrasound-guided technique and the anatomical basis for three clinically useful nerve blocks in dogs. Prospective experimental trial. Four hound-cross dogs aged 2 +/- 0 years (mean +/- SD) weighing 30 +/- 5 kg and four Beagles aged 2 +/- 0 years and weighing 8.5 +/- 0.5 kg. Axillary brachial plexus, femoral, and sciatic combined ultrasound/electrolocation-guided nerve blocks were performed sequentially and bilaterally using a lidocaine solution mixed with methylene blue. Sciatic nerve blocks were not performed in the hounds. After the blocks, the dogs were euthanatized and each relevant site dissected. Axillary brachial plexus block Landmark blood vessels and the roots of the brachial plexus were identified by ultrasound in all eight dogs. Anatomical examination confirmed the relationship between the four ventral nerve roots (C6, C7, C8, and T1) and the axillary vessels. Three roots (C7, C8, and T1) were adequately stained bilaterally in all dogs. Femoral nerve block Landmark blood vessels (femoral artery and femoral vein), the femoral and saphenous nerves and the medial portion of the rectus femoris muscle were identified by ultrasound in all dogs. Anatomical examination confirmed the relationship between the femoral vessels, femoral nerve, and the rectus femoris muscle. The femoral nerves were adequately stained bilaterally in all dogs. Sciatic nerve block. Ultrasound landmarks (semimembranosus muscle, the fascia of the biceps femoris muscle and the sciatic nerve) could be identified in all of the dogs. In the four Beagles, anatomical examination confirmed the relationship between the biceps femoris muscle, the semimembranosus muscle, and the sciatic nerve. In the Beagles, all but one of the sciatic nerves were stained adequately. Ultrasound-guided needle insertion is an accurate method for depositing local anesthetic for axillary brachial plexus, femoral, and sciatic nerve blocks.

Extradural en-plaque spinal meningioma with intraneural invasion.

PubMed

Tuli, Jayshree; Drzymalski, Dan Michael; Lidov, Hart; Tuli, Sagun

2012-01-01

Extradural spinal meningiomas are rare. Our understanding of purely extradural spinal meningiomas is incomplete because most reports rarely differentiate purely extradural meningiomas from extradural meningiomas with an intradural component. Occasionally, reports have described involvement of the adjacent nerve root, but there has never been a description of an extradural meningioma that actually infiltrates the nerve root. A 42-year-old woman presented with progressive lower extremity weakness and numbness below T3 during the span of 4 months with imaging evidence of an extradural lesion compressing the cord from T4 through T6. Surgical resection revealed an extradural mass extending through the foramen at T5-6 and encompassing the cord and T5 root on the left. Pathologically, the lesion was a World Health Organization grade I meningioma with nerve root invasion and a concerning elevated mindbomb homolog 1 (MIB-1) of 9.4%. Purely extradural meningiomas are rare, and our case is one of the first to describe a patient with an extradural meningioma that actually infiltrates the nerve root. Extradural spinal meningiomas are usually not adherent to the dura, but only appear to be adherent or invade (as in our patient) the adjacent nerve root. They are easily mistaken preoperatively and grossly intraoperatively for malignant metastatic tumors and can change the proposed surgical treatment. The long-term prognosis remains uncertain, but our patient's last follow-up suggests a favorable prognosis. Copyright © 2012 Elsevier Inc. All rights reserved.

Significance of radiological variables studied on orthopantamogram to pridict post-operative inferior alveoler nerve paresthesia after third molar extraction.

PubMed

Pathak, Sachin; Mishra, Nitin; Rastogi, Madhur Kant; Sharma, Shalini

2014-05-01

Removal of impacted third molar is a procedure that is often associated with post-operative complications. The rate of complications is somewhat high because of its proximity to the vital structures. Inferior alveolar nerve paresthesia is one of the common complications of impacted their molar surgery. This is due to intimate relationship between roots of mandibular third molar and inferior alveolar canal. To access the proximity of inferior alveolar canal to third molar many diagnostic methods are suggested but in conventional radiography orthopantamogram is considered as the best. There are many findings onorthopantamogram that are suggestive of close proximity of nerve to the canal. In this study authors reviewed seven radiographic findings related to proximity of roots to the inferior alveolar nerve as seen on orthopantamogram and try to find a relationship between these radiographic variables and presence of post-operative paresthesia. The study containd 100 impacted third molars need to be removed. Presence of radiographic findings on orthopantamogram were noted and analyzed, to find a relationship with occurrence of post-operative inferior alveolar nerve paresthesia. This study comprises of 100 impacted third molar teeth indicated for extraction. Cases were randomly selected from the patients, needs to undergo extraction of impacted mandibular third molar. After extraction cases were evaluated for occurrence of inferior alveolar nerve paresthesia. Stastical Analyisis: Data was transferred to SPss 21 software for frequency calculation, and two tailed p-values were obtained betweens these variables and post-operative paresthesia, by applying Fischer's exact test (GRAPH PAD SOFTWARE). Out of seven, four radiological findings that are grooving of roots, hooked roots, bifid roots and obliteration of white line are significantly related to post-operative paresthesia while bending of canal, narrow canal and darkening of tooth roots over the canal are not significantly associated with post-operative morbidity of facial nerve.

Boosted Regeneration and Reduced Denervated Muscle Atrophy by NeuroHeal in a Pre-clinical Model of Lumbar Root Avulsion with Delayed Reimplantation.

PubMed

Romeo-Guitart, David; Forés, Joaquim; Navarro, Xavier; Casas, Caty

2017-09-20

The "gold standard" treatment of patients with spinal root injuries consists of delayed surgical reconnection of nerves. The sooner, the better, but problems such as injury-induced motor neuronal death and muscle atrophy due to long-term denervation mean that normal movement is not restored. Herein we describe a preclinical model of root avulsion with delayed reimplantation of lumbar roots that was used to establish a new adjuvant pharmacological treatment. Chronic treatment (up to 6 months) with NeuroHeal, a new combination drug therapy identified using a systems biology approach, exerted long-lasting neuroprotection, reduced gliosis and matrix proteoglycan content, accelerated nerve regeneration by activating the AKT pathway, promoted the formation of functional neuromuscular junctions, and reduced denervation-induced muscular atrophy. Thus, NeuroHeal is a promising treatment for spinal nerve root injuries and axonal regeneration after trauma.

Analysis and evaluation of relative positions of mandibular third molar and mandibular canal impacts

PubMed Central

Kim, Hang-Gul

2014-01-01

Objectives This study used cone-beam computed tomography (CBCT) images to categorize the relationships between the mandibular canal and the roots and investigated the prevalence of nerve damage. Materials and Methods Through CBCT images, contact and three-dimensional positional relationships between the roots of the mandibular third molar and the mandibular canal were investigated. With this data, prevalence of nerve damage according to the presence of contact and three-dimensional positional relationships was studied. Other factors that affected the prevalence of nerve damage were also investigated. Results When the mandibular third molar and the mandibular canal were shown to have direct contact in CBCT images, the prevalence of nerve damage was higher than in other cases. Also, in cases where the mandibular canal was horizontally lingual to the mandibular third molar and the mandibular canal was vertically at the cervical level of the mandibular third molar, the prevalence of nerve damage was higher than in opposite cases. The percentage of mandibular canal contact with the roots of the mandibular third molar was higher when the mandibular canal was horizontally lingual to the mandibular third molar. Finally, the prevalence of nerve damage was higher when the diameter of the mandibular canal lumen suddenly decreased at the contact area between the mandibular canal and the roots, as shown in CBCT images. Conclusion The three-dimensional relationship of the mandibular third molar and the mandibular canal can help predict nerve damage and can guide patient expectations of the possibility and extent of nerve damage. PMID:25551092

Nerve transfer to relieve pain in upper brachial plexus injuries: Does it work?

PubMed

Emamhadi, Mohammadreza; Andalib, Sasan

2017-12-01

Patients with C5 and C6 nerve root avulsion may complain from pain. For these patients, end-to-side nerve transfer of the superficial radial nerve into the median nerve is suggested to relieve pain. Eleven patients (with a primary brachial plexus reconstruction) undergoing end-to-side nerve transfer of the superficial radial nerve into the ulnovolar part of the median nerve were assessed. Pain before surgery was compared to that at 6-month follow-up using visual analog scale (VAS) scores. A significant difference was seen between the mean VAS before (8.5) and after surgery (0.7) (P=0.0). After the six-month follow-up, 6 patients felt no pain according to VAS, notwithstanding 5 patients with a mild pain. The evidence from the present study suggests that end-to-side nerve transfer of the superficial radial nerve into the ulnovolar part of the median nerve is an effective technique in reducing pain in patients with C5 and C6 nerve root avulsion. Copyright © 2017 Elsevier B.V. All rights reserved.

Morphological differences in skeletal muscle atrophy of rats with motor nerve and/or sensory nerve injury★

PubMed Central

Zhao, Lei; Lv, Guangming; Jiang, Shengyang; Yan, Zhiqiang; Sun, Junming; Wang, Ling; Jiang, Donglin

2012-01-01

Skeletal muscle atrophy occurs after denervation. The present study dissected the rat left ventral root and dorsal root at L4-6 or the sciatic nerve to establish a model of simple motor nerve injury, sensory nerve injury or mixed nerve injury. Results showed that with prolonged denervation time, rats with simple motor nerve injury, sensory nerve injury or mixed nerve injury exhibited abnormal behavior, reduced wet weight of the left gastrocnemius muscle, decreased diameter and cross-sectional area and altered ultrastructure of muscle cells, as well as decreased cross-sectional area and increased gray scale of the gastrocnemius muscle motor end plate. Moreover, at the same time point, the pathological changes were most severe in mixed nerve injury, followed by simple motor nerve injury, and the changes in simple sensory nerve injury were the mildest. These findings indicate that normal skeletal muscle morphology is maintained by intact innervation. Motor nerve injury resulted in larger damage to skeletal muscle and more severe atrophy than sensory nerve injury. Thus, reconstruction of motor nerves should be considered first in the clinical treatment of skeletal muscle atrophy caused by denervation. PMID:25337102

[Incarcerated epitrochlear fracture with a cubital nerve injury].

PubMed

Moril-Peñalver, L; Pellicer-Garcia, V; Gutierrez-Carbonell, P

2013-01-01

Injuries of the medial epicondyle are relatively common, mostly affecting children between 7 and 15 years. The anatomical characteristics of this apophysis can make diagnosis difficult in minimally displaced fractures. In a small percentage of cases, the fractured fragment may occupy the retroepitrochlear groove. The presence of dysesthesias in the territory of the ulnar nerve requires urgent open reduction of the incarcerated fragment. A case of a seven-year-old male patient is presented, who required surgical revision due to a displaced medial epicondyle fracture associated with ulnar nerve injury. A review of the literature is also made. Copyright © 2013 SECOT. Published by Elsevier Espana. All rights reserved.

Spontaneous Regression of Inflammatory Pseudotumor in the Cauda Equina: A Case Report.

PubMed

Yoshimura, Kazuhiro; Sasaki, Manabu; Kojima, Masaru; Tsuruzono, Kouichirou; Matsumoto, Katsumi; Wakayama, Akatsuki; Yoshimine, Toshiki

2016-10-01

Spinal intradural extramedullary inflammatory pseudotumor (IPT) is an extremely rare entity. Spontaneous shrinking of a spinal IPT has never been reported. A case of an IPT of the cauda equina that regressed spontaneously is presented. A 78-year-old woman presented with hypoesthesia of both lower legs in the L4 nerve root distribution and motor weakness of the right leg. Preoperative CT myelography and MRI showed two tumor-like lesions located at T12-L1 and L2-3. The lesion at the T12-L1 level appeared to encase several nerve roots. The preoperative diagnosis was ependymoma, schwannoma, or malignant lymphoma. The tumors were biopsied. In the operation, the lesion turned out to consist of swollen and adherent nerve roots. On histopathological examination of the biopsied nerve roots, they were diagnosed as IPT. The patient's symptoms improved gradually without any treatment after the operation. The IPTs regressed on the postoperative MR images and disappeared at one year. This is the first report of spontaneous regression of an IPT in the spinal region. IPT should be considered in the differential diagnosis of a tumor that appears to involve several nerve roots on preoperative imaging, but surgery is necessary for diagnosis. Complete resection is not absolutely required if an intraoperative pathological diagnosis of the frozen section reveals IPT.

[Effects of Chinese herbal medicine Yiqi Huayu Recipe on apoptosis of dorsal root ganglion neurons and expression of caspase-3 in rats with lumbar nerve root compression].

PubMed

Xu, Le-qin; Li, Xiao-feng; Zhang, You-wei; Shu, Bing; Shi, Qi; Wang, Yong-jun; Zhou, Chong-jian

2010-12-01

To observe the effects of Yiqi Huayu Recipe, a Chinese compound herbal medicine, on apoptosis of dorsal root ganglion (DRG) neurons and expression of caspase-3 in rats after lumbar nerve root compression injury. A total of 40 male Sprague-Dawley rats were randomly allocated into 4 groups: control group, untreated group, Methylcobal group and Yiqi Huayu Recipe group. Surgery was performed on rats of untreated group, Methylcobal group and Yiqi Huayu Recipe group to place a micro-silica gel on right L₄ DRG, while control group received skin and paravertebral muscle incision only. Rats in Methylcobal group and Yiqi Huayu Recipe group were given Methylcobal by intramuscular injection and Yiqi Huayu Recipe intragastrically respectively. Rats in control group and untreated group received saline intragastrically as equal amount as Yiqi Huayu Recipe group. The compressed nerve roots were harvested at the 10th day after treatment. Apoptosis of DRG neurons was detected by terminal deoxynucleotidyl transferase-mediated nick-end labeling. Caspase-3 activity and mRNA expression in compressed nerve roots were detected with spectrophotography and real-time polymerase chain reaction respectively. Apoptosis of DRG neurons was significantly increased in the rat model. The apoptosis index of untreated group was higher than that of control group (P<0.01). Yiqi Huayu Recipe and Methylcobal could reduce the apoptosis of DRG neurons, and both groups showed a lower apoptosis index than untreated group (P<0.01). Caspase-3 activity and its gene expression were significantly increased in untreated group. The levels of caspase-3 activity and its gene expression in untreated group were higher than those in control group (P<0.05 or P<0.01). Yiqi Huayu Recipe and Methylcobal could reduce the overexpression of caspase-3 mRNA, and statistically significant differences were found between the untreated group and Yiqi Huayu Recipe group or Methylcobal group (P<0.01). Lumbar nerve root compression results in overexpression of caspase-3 in nerve root tissue and increase of DRG neuron apoptosis. Yiqi Huayu Recipe can inhibit the overexpression of caspase-3 and alleviate the apoptosis of DRG neurons after nerve injury.

Accuracy of physical examination for chronic lumbar radiculopathy

PubMed Central

2013-01-01

Background Clinical examination of patients with chronic lumbar radiculopathy aims to clarify whether there is nerve root impingement. The aims of this study were to investigate the association between findings at clinical examination and nerve root impingement, to evaluate the accuracy of clinical index tests in a specialised care setting, and to see whether imaging clarifies the cause of chronic radicular pain. Methods A total of 116 patients referred with symptoms of lumbar radiculopathy lasting more than 12 weeks and at least one positive index test were included. The tests were the straight leg raising test, and tests for motor muscle strength, dermatome sensory loss, and reflex impairment. Magnetic resonance imaging (n = 109) or computer tomography (n = 7) were imaging reference standards. Images were analysed at the level of single nerve root(s), and nerve root impingement was classified as present or absent. Sensitivities, specificities, and positive and negative likelihood ratios (LR) for detection of nerve root impingement were calculated for each individual index test. An overall clinical evaluation, concluding on the level and side of the radiculopathy, was performed. Results The prevalence of disc herniation was 77.8%. The diagnostic accuracy of individual index tests was low with no tests reaching positive LR >4.0 or negative LR <0.4. The overall clinical evaluation was slightly more accurate, with a positive LR of 6.28 (95% CI 1.06–37.21) for L4, 1.74 (95% CI 1.04–2.93) for L5, and 1.29 (95% CI 0.97–1.72) for S1 nerve root impingement. An overall clinical evaluation, concluding on the level and side of the radiculopathy was also performed, and receiver operating characteristic (ROC) analysis with area under the curve (AUC) calculation for diagnostic accuracy of this evaluation was performed. Conclusions The accuracy of individual clinical index tests used to predict imaging findings of nerve root impingement in patients with chronic lumbar radiculopathy is low when applied in specialised care, but clinicians’ overall evaluation improves diagnostic accuracy slightly. The tests are not very helpful in clarifying the cause of radicular pain, and are therefore inaccurate for guidance in the diagnostic workup of the patients. The study population was highly selected and therefore the results from this study should not be generalised to unselected patient populations in primary care nor to even more selected surgical populations. PMID:23837886

Comparison of hemihypoglossal nerve versus masseteric nerve transpositions in the rehabilitation of short-term facial paralysis using the Facial Clima evaluating system.

PubMed

Hontanilla, Bernardo; Marré, Diego

2012-11-01

Masseteric and hypoglossal nerve transfers are reliable alternatives for reanimating short-term facial paralysis. To date, few studies exist in the literature comparing these techniques. This work presents a quantitative comparison of masseter-facial transposition versus hemihypoglossal facial transposition with a nerve graft using the Facial Clima system. Forty-six patients with complete unilateral facial paralysis underwent reanimation with either hemihypoglossal transposition with a nerve graft (group I, n = 25) or direct masseteric-facial coaptation (group II, n = 21). Commissural displacement and commissural contraction velocity were measured using the Facial Clima system. Postoperative intragroup commissural displacement and commissural contraction velocity means of the reanimated versus the normal side were first compared using a paired sample t test. Then, mean percentages of recovery of both parameters were compared between the groups using an independent sample t test. Onset of movement was also compared between the groups. Significant differences of mean commissural displacement and commissural contraction velocity between the reanimated side and the normal side were observed in group I but not in group II. Mean percentage of recovery of both parameters did not differ between the groups. Patients in group II showed a significantly faster onset of movement compared with those in group I (62 ± 4.6 days versus 136 ± 7.4 days, p = 0.013). Reanimation of short-term facial paralysis can be satisfactorily addressed by means of either hemihypoglossal transposition with a nerve graft or direct masseteric-facial coaptation. However, with the latter, better symmetry and a faster onset of movement are observed. In addition, masseteric nerve transfer avoids morbidity from nerve graft harvesting. Therapeutic, III.

Morphometric analysis of the working zone for endoscopic lumbar discectomy.

PubMed

Min, Jun-Hong; Kang, Shin-Hyuk; Lee, Jang-Bo; Cho, Tai-Hyoung; Suh, Jung-Keun; Rhyu, Im-Joo

2005-04-01

Our study's purpose was to analyze the working zone for the current practice of endoscopic discectomy at the lateral exit zone of the intervertebral foramen (IVF) and to define a safe point for clinical practice. One hundred eighty-six nerve roots of the lumbar IVFs of cadaveric spines were studied. Upon lateral inspection, we measured the distance from the nerve root to the most dorsolateral margin of the disc and to the lateral edge of the superior articular process of the vertebra below at the plane of the superior endplate of the vertebra below. The angle between the root and the plane of the disc was also measured. The results showed that the mean distance from the nerve root to the most dorsolateral margin of the disc was 3.4 +/- 2.7 mm (range 0.0-10.8 mm), the mean distance from the nerve root to the lateral edge of the superior articular process of the vertebra below was 11.6 +/- 4.6 mm (range 4.1-24.3 mm), and the mean angle between the nerve root and the plane of the disc was 79.1 degrees +/- 7.6 degrees (range 56.0-90.0 degrees ). The values of the base of the working zone have a wide distribution. Blind puncture of annulus by the working cannula or obturator may be dangerous. The safer procedure would be the direct viewing of the annulus by endoscopy before annulotomy; the working cannula should be inserted into the foramen as close as possible to the facet joint.

Consecutive assessment of FA and ADC values of normal lumbar nerve roots from the junction of the dura mater.

PubMed

Miyagi, Ryo; Sakai, Toshinori; Yamabe, Eiko; Yoshioka, Hiroshi

2015-06-27

Diffusion weighted imaging (DWI) and diffusion tensor imaging (DTI) are widely used in the evaluation of the central nervous system and recently have been reported as a potential tool for diagnosis of the peripheral nerve or the lumbar nerve entrapment. The purpose of this study was to evaluate consecutive changes in apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values of normal lumbar nerve roots from the junction of the dura mater. The lumbar spinal nerves were examined in 6 male healthy volunteers (mean age, 35 years) with no experiences of sciatica, with a 3.0-T MR unit using a five-element phased-array surface coil. DTI was performed with the following imaging parameters: 11084.6/73.7 ms for TR/TE; b-value, 800 s/mm2; MPG, 33 directions; slice thickness, 1.5 mm; and total scan time, 7 min 35 s. ADC and FA values at all consecutive points along the L4, L5 and S1 nerves were quantified on every 1.5 mm slice from the junction of the dura mater using short fiber tracking. ADC values of all L4, 5, and S1 nerve roots decreased linearly up to 15 mm from the dura junction and was constant distally afterward. ADC values in the proximal portion demonstrated S1 > L5 > L4 (p < 0.05). On the other hand, FA values increased linearly up to 15 mm from the dura junction, and was constant distally afterward. FA values in the proximal portion showed L4 > L5 > S1 (p < 0.05). Our study demonstrated that ADC and FA values of each L4, 5, and S1 at the proximal portion from the junction of the dura matter changed linearly. It would be useful to know the normal profile of DTI values by location of each nerve root so that we can detect subtle abnormalities in each nerve root.

Coding of position by simultaneously recorded sensory neurones in the cat dorsal root ganglion

PubMed Central

Stein, R B; Weber, D J; Aoyagi, Y; Prochazka, A; Wagenaar, J B M; Shoham, S; Normann, R A

2004-01-01

Muscle, cutaneous and joint afferents continuously signal information about the position and movement of individual joints. How does the nervous system extract more global information, for example about the position of the foot in space? To study this question we used microelectrode arrays to record impulses simultaneously from up to 100 discriminable nerve cells in the L6 and L7 dorsal root ganglia (DRG) of the anaesthetized cat. When the hindlimb was displaced passively with a random trajectory, the firing rate of the neurones could be predicted from a linear sum of positions and velocities in Cartesian (x, y), polar or joint angular coordinates. The process could also be reversed to predict the kinematics of the limb from the firing rates of the neurones with an accuracy of 1–2 cm. Predictions of position and velocity could be combined to give an improved fit to limb position. Decoders trained using random movements successfully predicted cyclic movements and movements in which the limb was displaced from a central point to various positions in the periphery. A small number of highly informative neurones (6–8) could account for over 80% of the variance in position and a similar result was obtained in a realistic limb model. In conclusion, this work illustrates how populations of sensory receptors may encode a sense of limb position and how the firing of even a small number of neurones can be used to decode the position of the limb in space. PMID:15331686

Effect of improper scan alignment on retinal nerve fiber layer thickness measurements using Stratus optical coherence tomograph.

PubMed

Vizzeri, Gianmarco; Bowd, Christopher; Medeiros, Felipe A; Weinreb, Robert N; Zangwill, Linda M

2008-08-01

Misalignment of the Stratus optical coherence tomograph scan circle placed by the operator around the optic nerve head (ONH) during each retinal nerve fiber layer (RNFL) examination can affect the instrument reproducibility and its theoretical ability to detect true structural changes in the RNFL thickness over time. We evaluated the effect of scan circle placement on RNFL measurements. Observational clinical study. Sixteen eyes of 8 normal participants were examined using the Stratus optical coherence tomograph Fast RNFL thickness acquisition protocol (software version 4.0.7; Carl Zeiss Meditec, Dublin, CA). Four consecutive images were taken by the same operator with the circular scan centered on the optic nerve head. Four images each with the scan displaced superiorly, inferiorly, temporally, and nasally were also acquired. Differences in average and sectoral RNFL thicknesses were determined. For the centered scans, the coefficients of variation (CV) and the intraclass correlation coefficient for the average RNFL thickness measured were calculated. When the average RNFL thickness of the centered scans was compared with the average RNFL thickness of the displaced scans individually using analysis of variance with post-hoc analysis, no difference was found between the average RNFL thickness of the nasally (105.2 microm), superiorly (106.2 microm), or inferiorly (104.1 microm) displaced scans and the centered scans (106.4 microm). However, a significant difference (analysis of variance with Dunnett's test: F=8.82, P<0.0001) was found between temporally displaced scans (115.8 microm) and centered scans. Significant differences in sectoral RNFL thickness measurements were found between centered and each displaced scan. The coefficient of variation for average RNFL thickness was 1.75% and intraclass correlation coefficient was 0.95. In normal eyes, average RNFL thickness measurements are robust and similar with significant superior, inferior, and nasal scan displacement, but average RNFL thickness is greater when scans are displaced temporally. Parapapillary scan misalignment produces significant changes in RNFL assessment characterized by an increase in measured RNFL thickness in the quadrant in which the scan is closer to the disc, and a significant decrease in RNFL thickness in the quadrant in which the scan is displaced further from the optic disc.

Electromechanical Nerve Stimulator

NASA Technical Reports Server (NTRS)

Tcheng, Ping; Supplee, Frank H., Jr.; Prass, Richard L.

1993-01-01

Nerve stimulator applies and/or measures precisely controlled force and/or displacement to nerve so response of nerve measured. Consists of three major components connected in tandem: miniature probe with spherical tip; transducer; and actuator. Probe applies force to nerve, transducer measures force and sends feedback signal to control circuitry, and actuator positions force transducer and probe. Separate box houses control circuits and panel. Operator uses panel to select operating mode and parameters. Stimulator used in research to characterize behavior of nerve under various conditions of temperature, anesthesia, ventilation, and prior damage to nerve. Also used clinically to assess damage to nerve from disease or accident and to monitor response of nerve during surgery.

Lack of effectiveness of laser therapy applied to the nerve course and the correspondent medullary roots

PubMed Central

Sousa, Fausto Fernandes de Almeida; Ribeiro, Thaís Lopes; Fazan, Valéria Paula Sassoli; Barbieri, Claudio Henrique

2013-01-01

OBJECTIVE: To investigate the influence of low intensity laser irradiation on the regeneration of the fibular nerve of rats after crush injury. METHODS: Twenty-five rats were used, divided into three groups: 1) intact nerve, no treatment; 2) crushed nerve, no treatment; 3) crush injury, laser irradiation applied on the medullary region corresponding to the roots of the sciatic nerve and subsequently on the course of the damaged nerve. Laser irradiation was carried out for 14 consecutive days. RESULTS: Animals were evaluated by functional gait analysis with the peroneal functional index and by histomorphometric analysis using the total number of myelinated nerve fibers and their density, total number of Schwann cells, total number of blood vessels and the occupied area, minimum diameter of the fiber diameter and G-quotient. CONCLUSION: According to the statistical analysis there was no significant difference among groups and the authors conclude that low intensity laser irradiation has little or no influence on nerve regeneration and functional recovery. Laboratory investigation. PMID:24453650

Intrathecal Spread of Injectate Following an Ultrasound-Guided Selective C5 Nerve Root Injection in a Human Cadaver Model.

PubMed

Falyar, Christian R; Abercrombie, Caroline; Becker, Robert; Biddle, Chuck

2016-04-01

Ultrasound-guided selective C5 nerve root blocks have been described in several case reports as a safe and effective means to anesthetize the distal clavicle while maintaining innervation of the upper extremity and preserving diaphragmatic function. In this study, cadavers were injected with 5 mL of 0.5% methylene blue dye under ultrasound guidance to investigate possible proximal and distal spread of injectate along the brachial plexus, if any. Following the injections, the specimens were dissected and examined to determine the distribution of dye and the structures affected. One injection revealed dye extended proximally into the epidural space, which penetrated the dura mater and was present on the spinal cord and brainstem. Dye was noted distally to the divisions in 3 injections. The anterior scalene muscle and phrenic nerve were stained in all 4 injections. It appears unlikely that local anesthetic spread is limited to the nerve root following an ultrasound-guided selective C5 nerve root injection. Under certain conditions, intrathecal spread also appears possible, which has major patient safety implications. Additional safety measures, such as injection pressure monitoring, should be incorporated into this block, or approaches that are more distal should be considered for the acute pain management of distal clavicle fractures.

Coronectomy of the mandibular third molar: Respect for the inferior alveolar nerve.

PubMed

Kouwenberg, A J; Stroy, L P P; Rijt, E D Vree-V D; Mensink, G; Gooris, P J J

2016-05-01

The aim of this study was to evaluate the outcomes of coronectomy as an alternative surgical procedure to complete removal of the impacted mandibular third molar in patients with a suspected close relationship between the tooth root(s) and the mandibular canal. A total of 151 patients underwent coronectomy and were followed up with clinical examinations and panoramic radiographs for a minimum of 6 months after surgery. None of the patients exhibited inferior alveolar nerve injury. Eruption of the retained root(s) was more frequent in younger patients (18-35 years). Thirty-six patients (23.8%) exhibited insufficient growth of new bone in the alveolar defect, and 11.3% required a second surgical procedure to remove the root remnant(s). Our results indicate that coronectomy can be a reliable alternative to complete removal of the impacted mandibular third molar in patients exhibiting an increased risk of damage to the inferior alveolar nerve on panoramic radiographs. Copyright © 2016. Published by Elsevier Ltd.

Prevalence of extraforaminal nerve root compression below lumbosacral transitional vertebrae.

PubMed

Porter, Neil A; Lalam, Radhesh K; Tins, Bernhard J; Tyrrell, Prudencia N M; Singh, Jaspreet; Cassar-Pullicino, Victor N

2014-01-01

Although pathology at the first mobile segment above a lumbosacral transitional vertebra (LSTV) is a known source of spinal symptoms, nerve root compression below an LSTV, has only sporadically been reported. Our objective was to assess the prevalence of nerve root entrapment below an LSTV, review the causes of entrapment, and correlate with presenting symptoms. A retrospective review of MR and CT examinations of the lumbar spine was performed over a 5.5-year period in which the words "transitional vertebra" were mentioned in the report. Nerve root compression below an LSTV was assessed as well as the subtype of transitional vertebra. Correlation with clinical symptoms at referral was made. MR and CT examinations were also reviewed to exclude any other cause of symptoms above the LSTV. One hundred seventy-four patients were included in the study. Neural compression by new bone formation below an LSTV was demonstrated in 23 patients (13%). In all of these patients, there was a pseudarthrosis present on the side of compression due to partial sacralization with incomplete fusion. In three of these patients (13%), there was symptomatic correlation with no other cause of radiculopathy demonstrated. A further 13 patients (57%) had correlating symptoms that may in part be attributable to compression below an LSTV. Nerve root compression below an LSTV occurs with a prevalence of 13% and can be symptomatic in up to 70% of these patients. This region should therefore be carefully assessed in all symptomatic patients with an LSTV.

Effects of lower limb neurodynamic mobilization on intraneural fluid dispersion of the fourth lumbar nerve root: an unembalmed cadaveric investigation

PubMed Central

Gilbert, Kerry K.; Smith, Michael P.; Sobczak, Stéphane; James, C. Roger; Sizer, Phillip S.; Brismée, Jean-Michel

2015-01-01

Objectives Manual and physical therapists incorporate neurodynamic mobilisation (NDM) to improve function and decrease pain. Little is known about the mechanisms by which these interventions affect neural tissue. The objective of this research was to assess the effects of repetitive straight leg raise (SLR) NDM on the fluid dynamics within the fourth lumbar nerve root in unembalmed cadavers. Methods A biomimetic solution (Toluidine Blue Stock 1% and Plasma) was injected intraneurally, deep to the epineurium, into the L4 nerve roots of seven unembalmed cadavers. The initial dye spread was allowed to stabilise and measured with a digital calliper. Once the initial longitudinal dye spread stabilised, an intervention strategy (repetitive SLR) was applied incorporating NDMs (stretch/relax cycles) at a rate of 30 repetitions per minute for 5 minutes. Post-intervention calliper measurements of the longitudinal dye spread were measured. Results The mean experimental posttest longitudinal dye spread measurement (1.1 ± 0.9 mm) was significantly greater (P = 0.02) than the initial stabilised pretest longitudinal dye spread measurement. Increases ranged from 0.0 to 2.6 mm and represented an average of 7.9% and up to an 18.1% increase in longitudinal dye spread. Discussion Passive NDM in the form of repetitive SLR induced a significant increase in longitudinal fluid dispersion in the L4 nerve root of human cadaveric specimen. Lower limb NDM may be beneficial in promoting nerve function by limiting or altering intraneural fluid accumulation within the nerve root, thus preventing the adverse effects of intraneural oedema. PMID:26955255

Marked lateral deviation of the phrenic nerve due to variant origin and course of the thyrocervical trunk: a cadaveric study.

PubMed

Ogami, Keiko; Saiki, K; Okamoto, K; Wakebe, T; Manabe, Y; Imamura, T; Tsurumoto, T

2016-05-01

Phrenic nerve impairment can often lead to serious respiratory disorders under various pathological conditions. During routine dissection of an 88-year-old Japanese male cadaver, a victim of heart failure, we recognized an extremely rare variation of the right thyrocervical trunk arising from the subclavian artery laterally to the anterior scalene muscle. In addition to that, the ipsilateral phrenic nerve was drawn and displaced remarkably laterad by this vessel. We examined all of the branches arising from subclavian arteries, phrenic nerves and diaphragm muscles. The embryological background of this arterial variation is considered. The marked displacement with prolonged strain had a potential to cause phrenic nerve impairment with an atrophic change of the diaphragm muscle. Recently many image diagnostic technologies have been developed and are often used. However, it is still possible that rare variations like this case may be overlooked and can only be recognized by intimate regional examination while keeping these rare variations in mind.

MRI-guided and CT-guided cervical nerve root infiltration therapy: a cost comparison.

PubMed

Maurer, M H; Froeling, V; Röttgen, R; Bretschneider, T; Hartwig, T; Disch, A C; de Bucourt, M; Hamm, B; Streitparth, F

2014-06-01

To evaluate and compare the costs of MRI-guided and CT-guided cervical nerve root infiltration for the minimally invasive treatment of radicular neck pain. Between September 2009 and April 2012, 22 patients (9 men, 13 women; mean age: 48.2 years) underwent MRI-guided (1.0 Tesla, Panorama HFO, Philips) single-site periradicular cervical nerve root infiltration with 40 mg triamcinolone acetonide. A further 64 patients (34 men, 30 women; mean age: 50.3 years) were treated under CT fluoroscopic guidance (Somatom Definition 64, Siemens). The mean overall costs were calculated as the sum of the prorated costs of equipment use (purchase, depreciation, maintenance, and energy costs), personnel costs and expenditure for disposables that were identified for MRI- and CT-guided procedures. Additionally, the cost of ultrasound guidance was calculated. The mean intervention time was 24.9 min. (range: 12 - 36 min.) for MRI-guided infiltration and 19.7 min. (range: 5 - 54 min.) for CT-guided infiltration. The average total costs per patient were EUR 240 for MRI-guided interventions and EUR 124 for CT-guided interventions. These were (MRI/CT guidance) EUR 150/60 for equipment use, EUR 46/40 for personnel, and EUR 44/25 for disposables. The mean overall cost of ultrasound guidance was EUR 76. Cervical nerve root infiltration using MRI guidance is still about twice as expensive as infiltration using CT guidance. However, since it does not involve radiation exposure for patients and personnel, MRI-guided nerve root infiltration may become a promising alternative to the CT-guided procedure, especially since a further price decrease is expected for MRI devices and MR-compatible disposables. In contrast, ultrasound remains the less expensive method for nerve root infiltration guidance. © Georg Thieme Verlag KG Stuttgart · New York.

An analytical fiber bundle model for pullout mechanics of root bundles

NASA Astrophysics Data System (ADS)

Cohen, D.; Schwarz, M.; Or, D.

2011-09-01

Roots in soil contribute to the mechanical stability of slopes. Estimation of root reinforcement is challenging because roots form complex biological networks whose geometrical and mechanical characteristics are difficult to characterize. Here we describe an analytical model that builds on simple root descriptors to estimate root reinforcement. Root bundles are modeled as bundles of heterogeneous fibers pulled along their long axes neglecting root-soil friction. Analytical expressions for the pullout force as a function of displacement are derived. The maximum pullout force and corresponding critical displacement are either derived analytically or computed numerically. Key model inputs are a root diameter distribution (uniform, Weibull, or lognormal) and three empirical power law relations describing tensile strength, elastic modulus, and length of roots as functions of root diameter. When a root bundle with root tips anchored in the soil matrix is pulled by a rigid plate, a unique parameter, ?, that depends only on the exponents of the power law relations, dictates the order in which roots of different diameters break. If ? < 1, small roots break first; if ? > 1, large roots break first. When ? = 1, all fibers break simultaneously, and the maximum tensile force is simply the roots' mean force times the number of roots in the bundle. Based on measurements of root geometry and mechanical properties, the value of ? is less than 1, usually ranging between 0 and 0.7. Thus, small roots always fail first. The model shows how geometrical and mechanical characteristics of roots and root diameter distribution affect the pullout force, its maximum and corresponding displacement. Comparing bundles of roots that have similar mean diameters, a bundle with a narrow variance in root diameter will result in a larger maximum force and a smaller displacement at maximum force than a bundle with a wide diameter distribution. Increasing the mean root diameter of a bundle without changing the distribution's shape increases both the maximum force and corresponding displacement. Estimates of the maximum pullout forces for bundles of 100 roots with identical diameter distribution for different species range from less than 1 kN for barley (Hordeum vulgare) to almost 16 kN for pistachio (Pistacia lentiscus). The model explains why a commonly used assumption that all roots break simultaneously overpredicts the maximum pullout force by a factor of about 1.6-2. This ratio may exceed 3 for diameter distributions that have a large number of small roots like the exponential distribution.

C2 root nerve sheath tumors management.

PubMed

El-Sissy, Mohamed H; Mahmoud, Mostafa

2013-05-01

Upper cervical nerve sheath tumors (NST) arising mainly from C2 root and to lesser extent from C1 root are not uncommon, they constitute approximately 5-12% of spinal nerve sheath tumors and 18-30% of all cervical nerve sheath tumors, unique in presentation and their relationship to neighbouring structures owing to the discrete anatomy at the upper cervical-craniovertebral region, and have atendency for growth reaching large-sized tumors before manifesting clinically due to the capacious spinal canal at this region; accordingly the surgical approaches to such tumors are modified. The aim of this paper is to discuss the surgical strategies for upper cervical nerve sheath tumors. Eleven patients (8 male and 3 females), age range 28-63 years, with C2 root nerve sheath tumors were operated upon based on their anatomical relations to the spinal cord. The magnetic resonance imaging findings were utilized to determine the surgical approach. The tumors had extra- and intradural components in 10 patients, while in one the tumor was purely intradural. The operative approaches included varied from extreme lateral transcondylar approach(n = 1) to laminectomy, whether complete(n = 3) a or hemilaminectomy(n = 7), with partial facetectomy(n = 7), and with suboccipital craniectomy(n = 2). The clinical picture ranged from spasticity (n = 8, 72,72 %), tingling and numbness below neck (n = 6, 54,54 %), weakness (n = 6, 54,54 %), posterior column involvement (n = 4, 26,36 %), and neck pain (n = 4, 36,36 %). The duration of symptoms ranged from 1 to 54 months, total excision was performed in 7 patients; while in 3 patients an extraspinal component, and in 1 patient a small intradural component, were left in situ. Eight patients showed improvement of myelopathy; 2 patients maintained their grades. One poor-grade patient was deteriorated. The surgical approaches for the C2 root nerve sheath tumors should be tailored according to the relationship to the spinal cord, determined by magnetic resonance imaging.

Direct Posterior Bipolar Cervical Facet Radiofrequency Rhizotomy: A Simpler and Safer Approach to Denervate the Facet Capsule.

PubMed

Palea, Ovidiu; Andar, Haroon M; Lugo, Ramon; Granville, Michelle; Jacobson, Robert E

2018-03-14

Radiofrequency cervical rhizotomy has been shown to be effective for the relief of chronic neck pain, whether it be due to soft tissue injury, cervical spondylosis, or post-cervical spine surgery. The target and technique have traditionally been taught using an oblique approach to the anterior lateral capsule of the cervical facet joint. The goal is to position the electrode at the proximal location of the recurrent branch after it leaves the exiting nerve root and loops back to the cervical facet joint. The standard oblique approach to the recurrent nerve requires the testing of both motor and sensory components to verify the correct position and ensure safety so as to not damage the slightly more anterior nerve root. Bilateral lesions require the repositioning of the patient's neck. Poorly positioned electrodes can also pass anteriorly and contact the nerve root or vertebral artery. The direct posterior approach presented allows electrode positioning over a broader expanse of the facet joint without risk to the nerve root or vertebral artery. Over a four-year period, direct posterior radiofrequency ablation was performed under fluoroscopic guidance at multiple levels without neuro-stimulation testing with zero procedural neurologic events even as high as the C2 spinal segment. The direct posterior approach allows either unipolar or bipolar lesioning at multiple levels. Making a radiofrequency lesion along the larger posterior area of the facet capsule is as effective as the traditional target point closer to the nerve root but technically easier, allowing bilateral access and safety. The article will review the anatomy and innervation of the cervical facet joint and capsule, showing the diffuse nerve supply extending into the capsule of the facet joint that is more extensive than the recurrent medial sensory branches that have been the focus of radiofrequency lesioning.

Direct Posterior Bipolar Cervical Facet Radiofrequency Rhizotomy: A Simpler and Safer Approach to Denervate the Facet Capsule

PubMed Central

Palea, Ovidiu; Andar, Haroon M; Lugo, Ramon; Jacobson, Robert E

2018-01-01

Radiofrequency cervical rhizotomy has been shown to be effective for the relief of chronic neck pain, whether it be due to soft tissue injury, cervical spondylosis, or post-cervical spine surgery. The target and technique have traditionally been taught using an oblique approach to the anterior lateral capsule of the cervical facet joint. The goal is to position the electrode at the proximal location of the recurrent branch after it leaves the exiting nerve root and loops back to the cervical facet joint. The standard oblique approach to the recurrent nerve requires the testing of both motor and sensory components to verify the correct position and ensure safety so as to not damage the slightly more anterior nerve root. Bilateral lesions require the repositioning of the patient's neck. Poorly positioned electrodes can also pass anteriorly and contact the nerve root or vertebral artery. The direct posterior approach presented allows electrode positioning over a broader expanse of the facet joint without risk to the nerve root or vertebral artery. Over a four-year period, direct posterior radiofrequency ablation was performed under fluoroscopic guidance at multiple levels without neuro-stimulation testing with zero procedural neurologic events even as high as the C2 spinal segment. The direct posterior approach allows either unipolar or bipolar lesioning at multiple levels. Making a radiofrequency lesion along the larger posterior area of the facet capsule is as effective as the traditional target point closer to the nerve root but technically easier, allowing bilateral access and safety. The article will review the anatomy and innervation of the cervical facet joint and capsule, showing the diffuse nerve supply extending into the capsule of the facet joint that is more extensive than the recurrent medial sensory branches that have been the focus of radiofrequency lesioning. PMID:29765790

Infrared neural stimulation of human spinal nerve roots in vivo.

PubMed

Cayce, Jonathan M; Wells, Jonathon D; Malphrus, Jonathan D; Kao, Chris; Thomsen, Sharon; Tulipan, Noel B; Konrad, Peter E; Jansen, E Duco; Mahadevan-Jansen, Anita

2015-01-01

Infrared neural stimulation (INS) is a neurostimulation modality that uses pulsed infrared light to evoke artifact-free, spatially precise neural activity with a noncontact interface; however, the technique has not been demonstrated in humans. The objective of this study is to demonstrate the safety and efficacy of INS in humans in vivo. The feasibility of INS in humans was assessed in patients ([Formula: see text]) undergoing selective dorsal root rhizotomy, where hyperactive dorsal roots, identified for transection, were stimulated in vivo with INS on two to three sites per nerve with electromyogram recordings acquired throughout the stimulation. The stimulated dorsal root was removed and histology was performed to determine thermal damage thresholds of INS. Threshold activation of human dorsal rootlets occurred in 63% of nerves for radiant exposures between 0.53 and [Formula: see text]. In all cases, only one or two monitored muscle groups were activated from INS stimulation of a hyperactive spinal root identified by electrical stimulation. Thermal damage was first noted at [Formula: see text] and a [Formula: see text] safety ratio was identified. These findings demonstrate the success of INS as a fresh approach for activating human nerves in vivo and providing the necessary safety data needed to pursue clinically driven therapeutic and diagnostic applications of INS in humans.

The relationship between apical root resorption and orthodontic tooth movement in growing subjects.

PubMed

Xu, Tianmin; Baumrind, S

2002-07-01

To investigate the relationship between apical root resorption and orthodontic tooth movement in growing subjects. 58 growing subjects were collected randomly into the study sample and another 40 non-treated cases were used as control. The apical resoption of the upper central incisors was measured on periapical film and the incisor displacement was measured on lateral cephalogram. Using multiple linear regression analysis to examine the relationship between root resoption and the displacement of the upper incisor apex in each of four direction (retraction, advancement, intrusion and extrusion). The statistically significant negative association were found between resorption and both intrusion (P < 0.001) and extrusion (P < 0.05), but no significant association was found between resorption and both retraction and advancement. The regression analysis implied an average of 2.29 mm resorption in the absence of apical displacement. The likelihood that the magnitude of displacement of the incisor root is positively associated with root resoption in the population of treated growing subjects is very small.

Biomechanical evaluation of a transtibial pull-out meniscal root repair: challenging the bungee effect.

PubMed

Cerminara, Anthony J; LaPrade, Christopher M; Smith, Sean D; Ellman, Michael B; Wijdicks, Coen A; LaPrade, Robert F

2014-12-01

A common treatment for posterior meniscal root tears is transtibial pull-out repair, which has been biomechanically reported to restore tibiofemoral contact mechanics to those of the intact knee. Biomechanical data suggest that there is significant displacement of the repaired meniscal root with cyclic loading, which may be responsible for the poor healing and meniscal extrusion demonstrated in some clinical studies. The purpose of this study was to quantify the time-zero displacement of the posterior meniscal root in response to cyclic loading after transtibial pull-out repair and to quantify the individual contributions to displacement of the following: (1) suture elongation, (2) button-bone interface, and (3) meniscus-suture interface. The meniscus-suture interface was hypothesized to result in significantly more displacement than the button-bone interface or suture elongation. Descriptive laboratory study. Transtibial pull-out repair of the posterior medial meniscal root was performed in 6 porcine knees, and cyclic displacement was measured using a loading protocol representative of postoperative rehabilitation. Displacement from (1) suture elongation, (2) the button-bone interface, and (3) the meniscus-suture interface was determined by cyclically loading 6 specimens for each construct using the same loading protocol to determine the contribution of each component to the overall displacement of the repair construct. After 1000 cycles, the repair construct displaced by a mean of 3.28 mm (95% CI, 2.07-4.49). The meniscus-suture component (mean, 2.52 mm; 95% CI, 2.21-2.83) displaced significantly more than the button-bone component (mean, 0.90 mm; 95% CI, 0.64-1.15; P = .006) and suture elongation component (mean, 0.71 mm; 95% CI, 0.36-1.06; P = .006) after 1000 cycles. Displacement of the button-bone and suture elongation components was not significantly different after 1000 cycles (P = .720). There was substantial displacement of the posterior medial meniscal root repaired with the transtibial pull-out technique under a cyclic loading protocol simulating postoperative rehabilitation. The meniscus-suture interface contributed to significantly more displacement than the button-bone interface and suture elongation in the transtibial pull-out repair construct. The results provide a framework for optimizing the transtibial pull-out repair technique. Future studies should focus on improving suture fixation strength within the meniscus-suture interface. © 2014 The Author(s).

True navigation in migrating gulls requires intact olfactory nerves

PubMed Central

Wikelski, Martin; Arriero, Elena; Gagliardo, Anna; Holland, Richard A.; Huttunen, Markku J.; Juvaste, Risto; Mueller, Inge; Tertitski, Grigori; Thorup, Kasper; Wild, Martin; Alanko, Markku; Bairlein, Franz; Cherenkov, Alexander; Cameron, Alison; Flatz, Reinhard; Hannila, Juhani; Hüppop, Ommo; Kangasniemi, Markku; Kranstauber, Bart; Penttinen, Maija-Liisa; Safi, Kamran; Semashko, Vladimir; Schmid, Heidi; Wistbacka, Ralf

2015-01-01

During migratory journeys, birds may become displaced from their normal migratory route. Experimental evidence has shown that adult birds can correct for such displacements and return to their goal. However, the nature of the cues used by migratory birds to perform long distance navigation is still debated. In this experiment we subjected adult lesser black-backed gulls migrating from their Finnish/Russian breeding grounds (from >60°N) to Africa (to < 5°N) to sensory manipulation, to determine the sensory systems required for navigation. We translocated birds westward (1080 km) or eastward (885 km) to simulate natural navigational challenges. When translocated westwards and outside their migratory corridor birds with olfactory nerve section kept a clear directional preference (southerly) but were unable to compensate for the displacement, while intact birds and gulls with the ophthalmic branch of the trigeminal nerve sectioned oriented towards their population-specific migratory corridor. Thus, air-borne olfactory information seems to be important for migrating gulls to navigate successfully in some circumstances. PMID:26597351

True navigation in migrating gulls requires intact olfactory nerves.

PubMed

Wikelski, Martin; Arriero, Elena; Gagliardo, Anna; Holland, Richard A; Huttunen, Markku J; Juvaste, Risto; Mueller, Inge; Tertitski, Grigori; Thorup, Kasper; Wild, Martin; Alanko, Markku; Bairlein, Franz; Cherenkov, Alexander; Cameron, Alison; Flatz, Reinhard; Hannila, Juhani; Hüppop, Ommo; Kangasniemi, Markku; Kranstauber, Bart; Penttinen, Maija-Liisa; Safi, Kamran; Semashko, Vladimir; Schmid, Heidi; Wistbacka, Ralf

2015-11-24

During migratory journeys, birds may become displaced from their normal migratory route. Experimental evidence has shown that adult birds can correct for such displacements and return to their goal. However, the nature of the cues used by migratory birds to perform long distance navigation is still debated. In this experiment we subjected adult lesser black-backed gulls migrating from their Finnish/Russian breeding grounds (from >60°N) to Africa (to < 5°N) to sensory manipulation, to determine the sensory systems required for navigation. We translocated birds westward (1080 km) or eastward (885 km) to simulate natural navigational challenges. When translocated westwards and outside their migratory corridor birds with olfactory nerve section kept a clear directional preference (southerly) but were unable to compensate for the displacement, while intact birds and gulls with the ophthalmic branch of the trigeminal nerve sectioned oriented towards their population-specific migratory corridor. Thus, air-borne olfactory information seems to be important for migrating gulls to navigate successfully in some circumstances.

Mechanisms underlying electrical and mechanical responses of the bovine retractor penis to inhibitory nerve stimulation and to an inhibitory extract.

PubMed Central

Byrne, N. G.; Muir, T. C.

1985-01-01

The response of the bovine retractor penis (BRP) to stimulation of non-adrenergic, non-cholinergic (NANC) inhibitory nerves and to an inhibitory extract prepared from this muscle have been studied using intracellular microelectrode, sucrose gap and conventional mechanical recording techniques. Both inhibitory nerve stimulation and inhibitory extract hyperpolarized the membrane potential and relaxed spontaneous or guanethidine (3 X 10(-5) M)-induced tone. These effects were accompanied by an increase in membrane resistance. Following membrane potential displacement from an average value of -53 +/- 7 mV (n = 184; Byrne & Muir, 1984) inhibitory potentials to nerve stimulation were abolished at approximately -30 mV; there was no evidence of reversal. Displacement by inward hyperpolarizing current over the range -45 to -60 mV increased the inhibitory response to nerve stimulation and to inhibitory extract; at more negative potential values (above approximately -60 mV) the inhibitory potential decreased and was abolished (approximately -103 mV). There was no evidence of reversal. Removal of [K+]o reversibly reduced hyperpolarization to nerve stimulation and inhibitory extract. No enhancement was observed. Increasing the [K+]o to 20 mM reduced the inhibitory potential to nerve stimulation but this was restored by passive membrane hyperpolarization. Inhibitory potentials were obtained at membrane potential values exceeding that of the estimated EK (-49 mV). [Cl-]o-free or [Cl-]o-deficient solutions reduced and abolished (after some 20-25 min) the hyperpolarization produced by inhibitory nerve stimulation or inhibitory extract. The inhibitory potential amplitude following nerve stimulation was not restored by passive displacement of the membrane potential from -26 to -104 mV approximately. Ouabain (1-5 X 10(-5) M) reduced then (45-60 min later) abolished the inhibitory potential to nerve stimulation. The effects of this drug on the extract were not investigated. It is concluded that the inhibitory response to nerve stimulation and extract in the BRP may involve several ionic species. However, unlike that in gastrointestinal muscles the NANC response in the BRP is accompanied by an increased membrane resistance and does not primarily involve K+. The underlying mechanisms for the inhibitory response to both NANC nerve stimulation and inhibitory extract appear to be similar, compatible with the view that the latter may contain the inhibitory transmitter released from these nerves in this tissue. PMID:4027462

Distortion-free diffusion tensor imaging for evaluation of lumbar nerve roots: Utility of direct coronal single-shot turbo spin-echo diffusion sequence.

PubMed

Sakai, Takayuki; Doi, Kunio; Yoneyama, Masami; Watanabe, Atsuya; Miyati, Tosiaki; Yanagawa, Noriyuki

2018-06-01

Diffusion tensor imaging (DTI) based on a single-shot echo planer imaging (EPI-DTI) is an established method that has been used for evaluation of lumbar nerve disorders in previous studies, but EPI-DTI has problems such as a long acquisition time, due to a lot of axial slices, and geometric distortion. To solve these problems, we attempted to apply DTI based on a single-shot turbo spin echo (TSE-DTI) with direct coronal acquisition. Our purpose in this study was to investigate whether TSE-DTI may be more useful for evaluation of lumbar nerve disorders than EPI-DTI. First, lumbar nerve roots of five healthy volunteers were evaluated for optimization of imaging parameters with TSE-DTI including b-values and the number of motion proving gradient (MPG) directions. Subsequently, optimized TSE-DTI was quantitatively compared with conventional EPI-DTI by using fractional anisotropy (FA) values and visual scores in subjective visual evaluation of tractography. Lumbar nerve roots of six patients, who had unilateral neurologic symptoms in one leg, were evaluated by the optimized TSE-DTI. TSE-DTI with b-value of 400 s/mm 2 and 32 diffusion-directions could reduce the image distortion compared with EPI-DTI, and showed that the average FA values on the symptomatic side for six patients were significantly lower than those on the non-symptomatic side (P < 0.05). Tractography with TSE-DTI might show damaged areas of lumbar nerve roots without severe image distortion. TSE-DTI might improve the reproducibility in measurements of FA values for quantification of a nerve disorder, and would become a useful tool for diagnosis of low back pain. Copyright © 2018 Elsevier Inc. All rights reserved.

Karolinska institutet 200-year anniversary. Symposium on traumatic injuries in the nervous system: injuries to the spinal cord and peripheral nervous system - injuries and repair, pain problems, lesions to brachial plexus.

PubMed

Sköld, Mattias K; Svensson, Mikael; Tsao, Jack; Hultgren, Thomas; Landegren, Thomas; Carlstedt, Thomas; Cullheim, Staffan

2011-01-01

The Karolinska Institutet 200-year anniversary symposium on injuries to the spinal cord and peripheral nervous system gathered expertise in the spinal cord, spinal nerve, and peripheral nerve injury field spanning from molecular prerequisites for nerve regeneration to clinical methods in nerve repair and rehabilitation. The topics presented at the meeting covered findings on adult neural stem cells that when transplanted to the hypoglossal nucleus in the rat could integrate with its host and promote neuron survival. Studies on vascularization after intraspinal replantation of ventral nerve roots and microarray studies in ventral root replantation as a tool for mapping of biological patterns typical for neuronal regeneration were discussed. Different immune molecules in neurons and glia and their very specific roles in synapse plasticity after injury were presented. Novel strategies in repair of injured peripheral nerves with ethyl-cyanoacrylate adhesive showed functional recovery comparable to that of conventional epineural sutures. Various aspects on surgical techniques which are available to improve function of the limb, once the nerve regeneration after brachial plexus lesions and repair has reached its limit were presented. Moreover, neurogenic pain after amputation and its treatment with mirror therapy were shown to be followed by dramatic decrease in phantom limb pain. Finally clinical experiences on surgical techniques to repair avulsed spinal nerve root and the motoric as well as sensoric regain of function were presented.

Karolinska Institutet 200-Year Anniversary. Symposium on Traumatic Injuries in the Nervous System: Injuries to the Spinal Cord and Peripheral Nervous System – Injuries and Repair, Pain Problems, Lesions to Brachial Plexus

PubMed Central

Sköld, Mattias K.; Svensson, Mikael; Tsao, Jack; Hultgren, Thomas; Landegren, Thomas; Carlstedt, Thomas; Cullheim, Staffan

2011-01-01

The Karolinska Institutet 200-year anniversary symposium on injuries to the spinal cord and peripheral nervous system gathered expertise in the spinal cord, spinal nerve, and peripheral nerve injury field spanning from molecular prerequisites for nerve regeneration to clinical methods in nerve repair and rehabilitation. The topics presented at the meeting covered findings on adult neural stem cells that when transplanted to the hypoglossal nucleus in the rat could integrate with its host and promote neuron survival. Studies on vascularization after intraspinal replantation of ventral nerve roots and microarray studies in ventral root replantation as a tool for mapping of biological patterns typical for neuronal regeneration were discussed. Different immune molecules in neurons and glia and their very specific roles in synapse plasticity after injury were presented. Novel strategies in repair of injured peripheral nerves with ethyl-cyanoacrylate adhesive showed functional recovery comparable to that of conventional epineural sutures. Various aspects on surgical techniques which are available to improve function of the limb, once the nerve regeneration after brachial plexus lesions and repair has reached its limit were presented. Moreover, neurogenic pain after amputation and its treatment with mirror therapy were shown to be followed by dramatic decrease in phantom limb pain. Finally clinical experiences on surgical techniques to repair avulsed spinal nerve root and the motoric as well as sensoric regain of function were presented. PMID:21629875

A diagnostic study in patients with sciatica establishing the importance of localization of worsening of pain during coughing, sneezing and straining to assess nerve root compression on MRI.

PubMed

Verwoerd, Annemieke J H; Mens, Jan; El Barzouhi, Abdelilah; Peul, Wilco C; Koes, Bart W; Verhagen, Arianne P

2016-05-01

To test whether the localization of worsening of pain during coughing, sneezing and straining matters in the assessment of lumbosacral nerve root compression or disc herniation on MRI. Recently the diagnostic accuracy of history items to assess disc herniation or nerve root compression on magnetic resonance imaging (MRI) was investigated. A total of 395 adult patients with severe sciatica of 6-12 weeks duration were included in this study. The question regarding the influence of coughing, sneezing and straining on the intensity of pain could be answered on a 4 point scale: no worsening of pain, worsening of back pain, worsening of leg pain, worsening of back and leg pain. Diagnostic odds ratio's (DORs) were calculated for the various dichotomization options. The DOR changed into significant values when the answer option was more narrowed to worsening of leg pain. The highest DOR was observed for the answer option 'worsening of leg pain' with a DOR of 2.28 (95 % CI 1.28-4.04) for the presence of nerve root compression and a DOR of 2.50 (95 % CI 1.27-4.90) for the presence of a herniated disc on MRI. Worsening of leg pain during coughing, sneezing or straining has a significant diagnostic value for the presence of nerve root compression and disc herniation on MRI in patients with sciatica. This study also highlights the importance of the formulation of answer options in history taking.

Unsuspected reason for sciatica in Bertolotti's syndrome.

PubMed

Shibayama, M; Ito, F; Miura, Y; Nakamura, S; Ikeda, S; Fujiwara, K

2011-05-01

Patients with Bertolotti's syndrome have characteristic lumbosacral anomalies and often have severe sciatica. We describe a patient with this syndrome in whom standard decompression of the affected nerve root failed, but endoscopic lumbosacral extraforaminal decompression relieved the symptoms. We suggest that the intractable sciatica in this syndrome could arise from impingement of the nerve root extraforaminally by compression caused by the enlarged transverse process.

Surface localization of sacral foramina for neuromodulation of bladder function. An anatomical study.

PubMed

Hasan, S T; Shanahan, D A; Pridie, A K; Neal, D E

1996-01-01

A method is described for percutaneous localization of the sacral foramina, for neuromodulation of bladder function. We carried out an anatomical study of 5 male and 5 female human cadaver pelves. Using the described surface markings, needles were placed percutaneously into all sacral foramina from nine different angles. Paths of needle entry were studied by subsequent dissection. We observed that although it was possible to enter any sacral foramen at a wide range of insertion angles, the incidence of nerve root/vascular penetration increased with increasing angle of needle entry. Also, the incidence of nerve root penetration was higher with the medial approach compared with lateral entry. The insertion of a needle into the S1 foramen was associated with a higher incidence of nerve root penetration and presents a potential for arterial haemorrhage. On the other hand the smaller S3 and S4 nerve roots were surrounded by venous plexuses, presenting a potential source of venous haemorrhage during procedures. Our study suggests a new method for identifying the surface markings of sacral foramina and it describes the paths of inserted needles into the respective foramina. In addition, it has highlighted some potential risk factors secondary to needle insertion.

The effect of complete radial lateral meniscus posterior root tear on the knee contact mechanics: a finite element analysis.

PubMed

Bao, H R C; Zhu, D; Gong, H; Gu, G S

2013-03-01

In recent years, with technological advances in arthroscopy and magnetic resonance imaging and improved biomechanical studies of the meniscus, there has been some progress in the diagnosis and treatment of injuries to the roots of the meniscus. However, the biomechanical effect of posterior lateral meniscus root tears on the knee has not yet become clear. The purpose of this study was to determine the effect of a complete radial posterior lateral meniscus root tear on the knee contact mechanics and the function of the posterior meniscofemoral ligament on the knee with tear in the posterior root of lateral meniscus. A finite element model of the knee was developed to simulate different cases for intact knee, a complete radial posterior lateral meniscus root tear, a complete radial posterior lateral meniscus root tear with posterior meniscofemoral ligament deficiency, and total meniscectomy of the lateral meniscus. A compressive load of 1000 N was applied in all cases to calculate contact areas, contact pressure, and meniscal displacements. The complete radial posterior lateral meniscus root tear decreased the contact area and increased the contact pressure on the lateral compartment under compressive load. We also found a decreased contact area and increased contact pressure in the medial compartment, but it was not obvious compared to the lateral compartment. The lateral meniscus was radially displaced by compressive load after a complete radial posterior lateral meniscus root tear, and the displacement took place mainly in the body and posterior horn of lateral meniscus. There were further decrease in contact area and increases in contact pressure and raidial displacement of the lateral meniscus in the case of the complete posterior lateral meniscus root tear in combination with posterior meniscofemoral ligament deficiency. Complete radial posterior lateral meniscus root tear is not functionally equivalent to total meniscectomy. The posterior root torn lateral meniscus continues to provide some load transmission and distribution functions across the joint. The posterior meniscofemoral ligament prevents excessive radial displacement of the posterior root torn lateral meniscus and assists the torn lateral meniscus in transmitting a certain amount of stress in the lateral compartment.

Epicardial phrenic nerve displacement during catheter ablation of atrial and ventricular arrhythmias: procedural experience and outcomes.

PubMed

Kumar, Saurabh; Barbhaiya, Chirag R; Baldinger, Samuel H; Koplan, Bruce A; Maytin, Melanie; Epstein, Laurence M; John, Roy M; Michaud, Gregory F; Tedrow, Usha B; Stevenson, William G

2015-08-01

Arrhythmia origin in close proximity to the phrenic nerve (PN) can hinder successful catheter ablation. We describe our approach with epicardial PN displacement in such instances. PN displacement via percutaneous pericardial access was attempted in 13 patients (age 49±16 years, 9 females) with either atrial tachycardia (6 patients) or atrial fibrillation triggered from a superior vena cava focus (1 patient) adjacent to the right PN or epicardial ventricular tachycardia origin adjacent to the left PN (6 patients). An epicardially placed steerable sheath/4 mm-catheter combination (5 patients) or a vascular or an esophageal balloon (8 patients) was ultimately successful. Balloon placement was often difficult requiring manipulation via a steerable sheath. In 2 ventricular tachycardia cases, absence of PN capture was achieved only once the balloon was directly over the ablation catheter. In 3 atrial tachycardia patients, PN displacement was not possible with a balloon; however, a steerable sheath/catheter combination was ultimately successful. PN displacement allowed acute abolishment of all targeted arrhythmias. No PN injury occurred acutely or in follow up. Two patients developed acute complications (pleuro-pericardial fistula 1 and pericardial bleeding 1). Survival free of target arrhythmia was achieved in all atrial tachycardia patients; however, a nontargeted ventricular tachycardia recurred in 1 patient at a median of 13 months' follow up. Arrhythmias originating in close proximity to the PN can be targeted successfully with PN displacement with an epicardially placed steerable sheath/catheter combination, or balloon, but this strategy can be difficult to implement. Better tools for phrenic nerve protection are desirable. © 2015 American Heart Association, Inc.

Infrared neural stimulation of human spinal nerve roots in vivo

PubMed Central

Cayce, Jonathan M.; Wells, Jonathon D.; Malphrus, Jonathan D.; Kao, Chris; Thomsen, Sharon; Tulipan, Noel B.; Konrad, Peter E.; Jansen, E. Duco; Mahadevan-Jansen, Anita

2015-01-01

Abstract. Infrared neural stimulation (INS) is a neurostimulation modality that uses pulsed infrared light to evoke artifact-free, spatially precise neural activity with a noncontact interface; however, the technique has not been demonstrated in humans. The objective of this study is to demonstrate the safety and efficacy of INS in humans in vivo. The feasibility of INS in humans was assessed in patients (n=7) undergoing selective dorsal root rhizotomy, where hyperactive dorsal roots, identified for transection, were stimulated in vivo with INS on two to three sites per nerve with electromyogram recordings acquired throughout the stimulation. The stimulated dorsal root was removed and histology was performed to determine thermal damage thresholds of INS. Threshold activation of human dorsal rootlets occurred in 63% of nerves for radiant exposures between 0.53 and 1.23  J/cm2. In all cases, only one or two monitored muscle groups were activated from INS stimulation of a hyperactive spinal root identified by electrical stimulation. Thermal damage was first noted at 1.09  J/cm2 and a 2∶1 safety ratio was identified. These findings demonstrate the success of INS as a fresh approach for activating human nerves in vivo and providing the necessary safety data needed to pursue clinically driven therapeutic and diagnostic applications of INS in humans. PMID:26157986

The pain drawing as an instrument for identifying cervical spine nerve involvement in chronic whiplash-associated disorders.

PubMed

Bernhoff, Gabriella; Landén Ludvigsson, Maria; Peterson, Gunnel; Bertilson, Bo Christer; Elf, Madeleine; Peolsson, Anneli

2016-01-01

The aim of the study was to investigate the psychometric properties of a standardized assessment of pain drawing with regard to clinical signs of cervical spine nerve root involvement. This cross-sectional study included data collected in a randomized controlled study. Two hundred and sixteen patients with chronic (≥6 months) whiplash-associated disorders, grade 2 or 3, were included in this study. The validity, sensitivity, and specificity of a standardized pain drawing assessment for determining nerve root involvement were analyzed, compared to the clinical assessment. In addition, we analyzed the interrater reliability with 50 pain drawings. Agreement was poor between the standardized pain drawing assessment and the clinical assessment (kappa =0.11, 95% CI: -0.03 to 0.20). Sensitivity was high (93%), but specificity was low (19%). Interrater reliability was good (kappa =0.64, 95% CI: 0.53 to 0.76). The standardized pain drawing assessment of nerve root involvement in chronic whiplash-associated disorders was not in agreement with the clinical assessment. Further research is warranted to optimize the utilization of a pain/discomfort drawing as a supportive instrument for identifying nerve involvement in cervical spinal injuries.

Neurotization of the biceps muscle by end-to-side neurorraphy between ulnar and musculocutaneous nerves. A series of five cases.

PubMed

Franciosi, L F; Modestti, C; Mueller, S F

1998-01-01

Three patients with avulsed C5, C6, and C7 roots and two patients with avulsed C5 and C6 roots after trauma of the brachial plexus, were treated by neurotization of the biceps using nerve fibers derived from the ulnar nerve and obtained by end-to-side neurorraphy between the ulnar and musculocutaneous nerves. The age of patients ranged from 19 to 45. The interval between the accident and surgery was 2 to 13 months. Return of biceps contraction was observed 4 to 6 months after surgery. Four patients recovered grade 4 elbow flexion. One 45-year-old patient did not obtain any biceps contraction after 9 months.

New Theoretical Model of Nerve Conduction in Unmyelinated Nerves

PubMed Central

Akaishi, Tetsuya

2017-01-01

Nerve conduction in unmyelinated fibers has long been described based on the equivalent circuit model and cable theory. However, without the change in ionic concentration gradient across the membrane, there would be no generation or propagation of the action potential. Based on this concept, we employ a new conductive model focusing on the distribution of voltage-gated sodium ion channels and Coulomb force between electrolytes. Based on this new model, the propagation of the nerve conduction was suggested to take place far before the generation of action potential at each channel. We theoretically showed that propagation of action potential, which is enabled by the increasing Coulomb force produced by inflowing sodium ions, from one sodium ion channel to the next sodium channel would be inversely proportionate to the density of sodium channels on the axon membrane. Because the longitudinal number of sodium ion channel would be proportionate to the square root of channel density, the conduction velocity of unmyelinated nerves is theoretically shown to be proportionate to the square root of channel density. Also, from a viewpoint of equilibrium state of channel importation and degeneration, channel density was suggested to be proportionate to axonal diameter. Based on these simple basis, conduction velocity in unmyelinated nerves was theoretically shown to be proportionate to the square root of axonal diameter. This new model would also enable us to acquire more accurate and understandable vision on the phenomena in unmyelinated nerves in addition to the conventional electric circuit model and cable theory. PMID:29081751

C2 spondylotic radiculopathy: the nerve root impingement mechanism investigated by para-sagittal CT/MRI, dynamic rotational CT, intraoperative microscopic findings, and treated by microscopic posterior foraminotomy.

PubMed

Fujiwara, Yasushi; Izumi, Bunichiro; Fujiwara, Masami; Nakanishi, Kazuyoshi; Tanaka, Nobuhiro; Adachi, Nobuo; Manabe, Hideki

2017-04-01

C2 radiculopathy is known to cause occipito-cervical pain, but their pathology is unclear because of its rarity and unique anatomy. In this paper, we investigated the mechanism of C2 radiculopathy that underwent microscopic cervical foraminotomies (MCF). Three cases with C2 radiculopathy treated by MCF were investigated retrospectively. The mean follow-up period was 24 months. Pre-operative symptoms, imaging studies including para-sagittal CT and MRI, rotational dynamic CT, and intraoperative findings were investigated. There were 1 male and 2 females. The age of patients were ranged from 50 to 79 years. All cases had intractable occipito-cervical pain elicited by the cervical rotation. C2 nerve root block was temporally effective. There was unilateral spondylosis in symptomatic side without obvious atlatoaxial instability. Para-sagittal MRI and CT showed severe foraminal stenosis at C1-C2 due to the bony spur derived from the lateral atlanto-axial joints. In one case, dynamic rotational CT showed that the symptomatic foramen became narrower on rotational position. MCF was performed in all cases, and the C2 nerve root was impinged between the inferior edge of the C1 posterior arch and bony spur from the C1-C2 joint. After surgery, occipito-cervical pain disappeared. This study demonstrated that mechanical impingement of the C2 nerve root is one of the causes of occipito-cervical pain and it was successfully treated by microscopic resection of the inferior edge of the C1 posterior arch. Para-sagittal CT and MRI, rotational dynamic CT, and nerve root block were effective for diagnosis.

Observations on the Use of Seprafilm® on the Brachial Plexus in 249 Operations for Neurogenic Thoracic Outlet Syndrome

PubMed Central

Hammond, Sharon L.; Rao, Neal M.

2007-01-01

Purpose Seprafilm® was initially used successfully as a membrane to reduce abdominal adhesions. Subsequently it was tried in a number of other areas to reduce postoperative scarring. Seprafilm® was employed in this study to see if it would reduce postoperative scarring after supraclavicular thoracic outlet decompression for neurogenic thoracic outlet syndrome (NTOS). Material and methods There were 249 operations for primary NTOS (185) and recurrent NTOS (64). Seprafilm® was applied to the nerve roots at the end of each procedure. Diagnosis was established by careful history and extensive physical exam consisting of several provocative maneuvers. Scalene muscle block confirmed the diagnosis. Results Success rates for primary operations, 1–2 years postoperation were 74% for scalenectomy without first rib resection and 70% for scalenectomy with first rib resection. For reoperations, success rate for scalenectomy and neurolysis after transaxillary rib resection was 78% whereas success rate for neurolysis after supraclavicular scalenectomy was 68%. Seprafilm® did not significantly improve overall results compared to our results 15 years ago, although in reoperations there was a trend toward improvement with Seprafilm®. Observations in 10 reoperations after use of Seprafilm® revealed that there were fewer adhesions between fat pad and nerve roots, making it much easier to find the nerve roots. Recurrence was because of scar formation around individual nerve roots. Conclusion Seprafilm® made reoperations easier by reducing scarring between scalene fat pad and brachial plexus. However, it did not prevent scar tissue forming around the individual nerve roots nor did it significantly lower the failure rate for primary operations. The trend supported the use of Seprafilm® in reoperations. PMID:18780049

The afferent pathways of discogenic low-back pain. Evaluation of L2 spinal nerve infiltration.

PubMed

Nakamura, S I; Takahashi, K; Takahashi, Y; Yamagata, M; Moriya, H

1996-07-01

The afferent pathways of discogenic low-back pain have not been fully investigated. We hypothesised that this pain was transmitted mainly by sympathetic afferent fibres in the L2 nerve root, and in 33 patients we used selective local anaesthesia of this nerve. Low-back pain disappeared or significantly decreased in all patients after the injection. Needle insertion provoked pain which radiated to the low back in 23 patients and the area of skin hypoalgesia produced included the area of pre-existing pain in all but one. None of the nine patients with related sciatica had relief of that component of their symptoms. Our findings show that the main afferent pathways of pain from the lower intervertebral discs are through the L2 spinal nerve root, presumably via sympathetic afferents from the sinuvertebral nerves. Discogenic low-back pain should be regarded as a visceral pain in respect of its neural pathways. Infiltration of the L2 nerve is a useful diagnostic test and also has some therapeutic value.

Brachial Plexus Injury in a 6-Year-Old Boy with 100% Displaced Proximal Humeral Metaphyseal Fracture: A Case Presentation.

PubMed

Jovanovich, Elizabeth Nora; Howard, James F

2017-12-01

Posttraumatic brachial plexopathies can occur following displaced proximal humeral fractures, causing profound functional deficits. Described here is an unusual case of a displaced proximal humeral metaphyseal fracture in a young child. The patient underwent closed reduction and serial casting, but hand weakness and forearm sensory loss persisted. Needle electromyography localized the injury to the mid/proximal arm near the fracture site, resulting in damage to the posterior and medial cords of the brachial plexus with profound involvement of the radial, ulnar, and median nerves and sparing of the axillary nerve. After months of occupational therapy, hand strength improved, with a nearly full return of function. V. Copyright © 2017 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

Comparison of hemihypoglossal-facial nerve transposition with a cross-facial nerve graft and muscle transplant for the rehabilitation of facial paralysis using the facial clima method.

PubMed

Hontanilla, Bernardo; Vila, Antonio

2012-02-01

To compare quantitatively the results obtained after hemihypoglossal nerve transposition and microvascular gracilis transfer associated with a cross facial nerve graft (CFNG) for reanimation of a paralysed face, 66 patients underwent hemihypoglossal transposition (n = 25) or microvascular gracilis transfer and CFNG (n = 41). The commissural displacement (CD) and commissural contraction velocity (CCV) in the two groups were compared using the system known as Facial clima. There was no inter-group variability between the groups (p > 0.10) in either variable. However, intra-group variability was detected between the affected and healthy side in the transposition group (p = 0.036 and p = 0.017, respectively). The transfer group had greater symmetry in displacement of the commissure (CD) and commissural contraction velocity (CCV) than the transposition group and patients were more satisfied. However, the transposition group had correct symmetry at rest but more asymmetry of CCV and CD when smiling.

Extracorporeal Stimulation of Sacral Nerve Roots for Observation of Pelvic Autonomic Nerve Integrity: Description of a Novel Methodological Setup.

PubMed

Moszkowski, Tomasz; Kauff, Daniel W; Wegner, Celine; Ruff, Roman; Somerlik-Fuchs, Karin H; Kruger, Thilo B; Augustyniak, Piotr; Hoffmann, Klaus-Peter; Kneist, Werner

2018-03-01

Neurophysiologic monitoring can improve autonomic nerve sparing during critical phases of rectal cancer surgery. To develop a system for extracorporeal stimulation of sacral nerve roots. Dedicated software controlled a ten-electrode stimulation array by switching between different electrode configurations and current levels. A built-in impedance and current level measurement assessed the effectiveness of current injection. Intra-anal surface electromyography (sEMG) informed on targeting the sacral nerve roots. All tests were performed on five pig specimens. During switching between electrode configurations, the system delivered 100% of the set current (25 mA, 30 Hz, 200 μs cathodic pulses) in 93% of 250 stimulation trains across all specimens. The impedance measured between single stimulation array contacts and corresponding anodes across all electrode configurations and specimens equaled 3.7 ± 2.5 kΩ. The intra-anal sEMG recorded a signal amplitude increase as previously observed in the literature. When the stimulation amplitude was tested in the range from 1 to 21 mA using the interconnected contacts of the stimulation array and the intra-anal anode, the impedance remained below 250 Ω and the system delivered 100% of the set current in all cases. Intra-anal sEMG showed an amplitude increase for current levels exceeding 6 mA. The system delivered stable electric current, which was proved by built-in impedance and current level measurements. Intra-anal sEMG confirmed the ability to target the branches of the autonomous nervous system originating from the sacral nerve roots. Stimulation outside of the operative field during rectal cancer surgery is feasible and may improve the practicality of pelvic intraoperative neuromonitoring.

Military Aircrew Seating: a Human Factors Engineering Approach

DTIC Science & Technology

1989-12-01

deformation of lumbar motion segments can be reduced by using lumbar support to increase lumbar spine lordosis . 3. Disc pressure can be reduced by using...increase in lumbar lordosis (curve of the lumbar spine), which placed them in a position which closer approximated that of balanced muscle relaxation... lordosis and curvature length. This flattening of the lumbar spine tends to stretch the overlying nerve root, and increases nerve root irritation and

Unusual complication after genioplasty.

PubMed

Avelar, Rafael Linard; Sá, Carlos Diego Lopes; Esses, Diego Felipe Silveira; Becker, Otávio Emmel; Soares, Eduardo Costa Studart; de Oliveira, Rogerio Belle

2014-01-01

Facial beauty depends on shape, proportion, and harmony between the facial thirds. The chin is one of the most important components of the inferior third and has an important role on the definition of facial aesthetic and harmony in both frontal and lateral views. There are 2 principal therapeutic approaches that one can choose to treat mental deformities, alloplastic implants, and mental basilar ostectomy, also known as genioplasty. The latest is more commonly used because of great versatility in the correction of three-dimensional deformities of the chin and smaller taxes of postoperative complications. Possible transoperative and postoperative complications of genioplasty include mental nerve lesion, bleeding, damage to tooth roots, bone resorption of the mobilized segment, mandibular fracture, ptosis of the lower lip, and failure to stabilize the ostectomized segment. The study presents 2 cases of displacement of the osteotomized segment after genioplasty associated with facial trauma during postoperative orthognathic surgery followed by rare complications with no reports in the literature.

Occipital neuralgia secondary to unilateral atlantoaxial osteoarthritis: Case report and review of the literature.

PubMed

Guha, Daipayan; Mohanty, Chandan; Tator, Charles H; Shamji, Mohammed F

2015-01-01

Atlantoaxial osteoarthritis (AAOA), either in isolation or in the context of generalized peripheral or spinal arthritis, presents most commonly with neck pain and limitation of cervical rotational range of motion. Occipital neuralgia (ON) is only rarely attributed to AAOA, as fewer than 30 cases are described in the literature. A 64-year-old female presented with progressive incapacitating cervicalgia and occipital headaches, refractory to medications, and local anesthetic blocks. Computed tomography and magnetic resonance imaging studies documented advanced unilateral atlantoaxial arthrosis with osteophytic compression that dorsally displaced the associated C2 nerve root. Surgical decompression and atlantoaxial fusion achieved rapid and complete relief of neuralgia. Ultimately, postoperative spinal imaging revealed osseous union. Atlantoaxial arthrosis must be considered in the differential diagnosis of ON. Surgical treatment is effective for managing refractory cases. Intraoperative neuronavigation is also a useful adjunct to guide instrumentation and the intraoperative extent of bony decompression.

Afferent fibers and sensory ganglion cells within the oculomotor nerve in some mammals and man. II. Electrophysiological investigations.

PubMed

Manni, E; Bortolami, R; Pettorossi, V E; Lucchi, M L; Callegari, E

1978-01-01

The main aim of the present study was to localize with electrophysiological techniques the central projections and terminations of the aberrant trigeminal fibres contained in the oculomotor nerve of the lamb. After severing a trigeminal root, single-shock electrical stimulation of the trigeminal axons present in the central stump of the ipsilateral oculomotor nerve evoked field potentials in the area of, i) the subnucleus gelatinosus of the nucleus caudalis trigemini at the level of C1-C2; ii) the main sensory trigeminal nucleus; iii) the descending trigeminal nucleus and tract; iv) the adjacent reticular formation. Units whose discharge rate was influenced by such a stimulation were also found in the same territories. These regions actually exhibited degenerations after cutting an oculomotor nerve. We conclude, therefore, that the trigeminal fibres which leave the Vth nerve at the level of the cavernous sinus and enter the brain stem through the IIIrd nerve, end in the same structures which receive the terminations of the afferent fibres entering the brain stem through the sensory trigeminal root.

Sonographic evaluation of peripheral nerves in subtypes of Guillain-Barré syndrome.

PubMed

Mori, Atsuko; Nodera, Hiroyuki; Takamatsu, Naoko; Maruyama-Saladini, Keiko; Osaki, Yusuke; Shimatani, Yoshimitsu; Kaji, Ryuji

2016-05-15

Sonography of peripheral nerves can depict alteration of nerve sizes that could reflect inflammation and edema in inflammatory and demyelinating neuropathies. Guillain-Barré syndrome (GBS). Information on sonographic comparison of an axonal subtype (acute motor [and sensory] axonal neuropathy [AMAN and AMSAN]) and a demyelinating subtype (acute inflammatory demyelinating polyneuropathy [AIDP]) has been sparse. Sonography of peripheral nerves and cervical nerve roots were prospectively recorded in patients with GBS who were within three weeks of disease onset. Five patients with AIDP and nine with AMAN (n=6)/AMSAN (n=3) were enrolled. The patients with AIDP showed evidence of greater degrees of demyelination (e.g., slower conduction velocities and increased distal latencies) than those with AMAN/AMSAN. The patients with AIDP tended to show enlarged nerves in the proximal segments and in the cervical roots, whereas the patients with AMAN/AMSAN had greater enlargement in the distal neve segment, especially in the median nerve (P = 0.03; Wrist-axilla cross-sectional ratio). In this small study, two subtypes of GBS showed different patterns of involvement that might reflect different pathomechanisms. Copyright © 2016 Elsevier B.V. All rights reserved.

F-18 FDG PET/CT findings of a case of sacral nerve root neurolymphomatosis that occurred during chemotherapy.

PubMed

Suga, Kazuyoshi; Yasuhiko, Kawakami; Matsunaga, Naofumi; Yujiri, Toshiaki; Nakazora, Tatsuki; Ariyoshi, Kouichi

2011-01-01

Neurolymphomatosis (NL) is a rare, unique subtype of lymphomatous infiltration of peripheral nerves. Clinical/radiologic diagnosis of NL is challenging. We report F-18 FDG PET/CT findings of a case of breast diffuse large B-cell lymphoma, in which NL developed regardless of regression of systemic lesions during induction chemotherapy. FDG PET/CT showed characteristic findings of well-demarcated, linear abnormal FDG uptake along a sacral vertebral foramen, leading to diagnosis of NL, with the finding of thickened nerve roots on magnetic resonance imaging. Altered chemotherapeutic regimen resulted in disappearance of these abnormal FDG uptake, with recovery of neurologic symptoms. Peripheral nerve NL may occur during chemotherapy, and FDG PET/CT can be a useful imaging modality in diagnosis and monitoring of therapeutic response of this disease.

Ultrasonographic nerve enlargement of the median and ulnar nerves and the cervical nerve roots in patients with demyelinating Charcot-Marie-Tooth disease: distinction from patients with chronic inflammatory demyelinating polyneuropathy.

PubMed

Sugimoto, Takamichi; Ochi, Kazuhide; Hosomi, Naohisa; Takahashi, Tetsuya; Ueno, Hiroki; Nakamura, Takeshi; Nagano, Yoshito; Maruyama, Hirofumi; Kohriyama, Tatsuo; Matsumoto, Masayasu

2013-10-01

Demyelinating Charcot-Marie-Tooth disease (CMT) and chronic inflammatory demyelinating polyneuropathy (CIDP) are both demyelinating polyneuropathies. The differences in nerve enlargement degree and pattern at multiple evaluation sites/levels are not well known. We investigated the differences in nerve enlargement degree and the distribution pattern of nerve enlargement in patients with demyelinating CMT and CIDP, and verified the appropriate combination of sites/levels to differentiate between these diseases. Ten patients (aged 23-84 years, three females) with demyelinating CMT and 16 patients (aged 30-85 years, five females) with CIDP were evaluated in this study. The nerve sizes were measured at 24 predetermined sites/levels from the median and ulnar nerves and the cervical nerve roots (CNR) using ultrasonography. The evaluation sites/levels were classified into three regions: distal, intermediate and cervical. The number of sites/levels that exhibited nerve enlargement (enlargement site number, ESN) in each region was determined from the 24 sites/levels and from the selected eight screening sites/levels, respectively. The cross-sectional areas of the peripheral nerves were markedly larger at all evaluation sites in patients with demyelinating CMT than in patients with CIDP (p < 0.01). However, the nerve sizes of CNR were not significantly different between patients with either disease. When we evaluated ESN of four selected sites for screening from the intermediate region, the sensitivity and specificity to distinguish between demyelinating CMT and CIDP were 0.90 and 0.94, respectively, with the cut-off value set at four. Nerve ultrasonography is useful to detect nerve enlargement and can clarify morphological differences in nerves between patients with demyelinating CMT and CIDP.

Structural Variation of Alpha-synuclein with Temperature by a Coarse-grained Approach with Knowledge-based Interactions (Postprint)

DTIC Science & Technology

2015-07-01

the radius of gyration in detail as a function FIG. 5. Variation of the root mean square (RMS) displacement of the center of mass of the protein with...depends on the temperature. The global motion can be examined by analyzing the variation of the root mean square displacement (RMS) of the center of...and global physical quantities during the course of simula- tion, including the energy of each residue, its mobility, mean square displacement of the

Bilateral spinal anterior horn lesions in acute motor axonal neuropathy.

PubMed

Sawada, Daisuke; Fujii, Katsunori; Misawa, Sonoko; Shiohama, Tadashi; Fukuhara, Tomoyuki; Fujita, Mayuko; Kuwabara, Satoshi; Shimojo, Naoki

2018-05-28

Guillain-Barré syndrome is an acute immune-mediated peripheral polyneuropathy. Neuroimaging findings from patients with this syndrome have revealed gadolinium enhancement in the cauda equina and in the anterior and posterior nerve roots, but intra-spinal lesions have never been described. Herein, we report, for the first time, bilateral spinal anterior horn lesions in a patient with an acute motor axonal neuropathy form of Guillain-Barré syndrome. The patient was a previously healthy 13-year-old Japanese girl, who exhibited acute-onset flaccid tetraplegia and loss of tendon reflexes. Nerve conduction studies revealed motor axonal damage, leading to the diagnosis of acute motor axonal neuropathy. Notably, spinal magnetic resonance imaging revealed bilateral anterior horn lesions on T2-weighted imaging at the Th11-12 levels, as well as gadolinium enhancement of the cauda equina and anterior and posterior nerve roots. The anterior horn lesions were most prominent on day 18, and their signal intensity declined thereafter. Although intravenous treatment with immunoglobulins was immediately administered, the motor function was not completely regained. We propose that anterior spinal lesions might be responsible for the prolonged neurological disability of patients with Guillain-Barré syndrome, possibly produced by retrograde progression from the affected anterior nerve roots to the intramedullary roots, and the anterior horn motor neurons. Copyright © 2018 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

Anatomical evidence for the anterior plate fixation of sacroiliac joint.

PubMed

Bai, Zhibiao; Gao, Shichang; Liu, Jia; Liang, Anlin; Yu, Weihua

2018-01-01

The iatrogenic injuries to the lumbar nerves during the fixation the sacroiliac (SI) joint fractures with anterior plates were often reported. No specific method had been reported to avoid it. This study was done to find a safer way of placing the anterior plates and screws for treating the sacroiliac (SI) joint fracture and/or dislocation. The research was performed using 8 male and 7 female normal corpse pelvic specimens preserved by 10% formalin solution. Try by measuring the horizontal distance from L4, L5 nerve roots to the sacroiliac joint and perpendicular distance from L4, L5 nerve roots to the ala sacralis, the length of L4, L5 nerve roots from intervertebral foramen to the edge of true pelvis, the diameter of L4, L5 nerve roots. The angles between the sacroiliac joint and sagittal plane were measured on the CT images. The horizontal distance between the lateral side of the anterior branches of L4, L5 nerve roots and the sacroiliac joint decreased gradually from the top to the bottom. The widest distances for L4,5 were 2.1 cm (range, 1.74-2.40) and 2.7 cm (range, 2.34-3.02 cm), respectively. The smallest distances for L4, 5 were 1.2 cm (range, 0.82-1.48 cm) and 1.5 cm (range, 1.08-1.74 cm), respectively. On CT images, the angle between the sacroiliac joint and sagittal plane was about 30°. If we use two anterior plates to fix the sacroiliac joint, It is recommended to place one plate on the superior one third part of the joint, with exposing medially no more than 2.5 cm and the other in the middle one third part of the joint, with elevating periosteum medially no more than 1.5 cm. The screws in the sacrum are advised to incline medially about 30° directing to the true pelvis. Copyright © 2017. Published by Elsevier B.V.

Sciatica caused by lumbar epidural gas.

PubMed

Belfquih, Hatim; El Mostarchid, Brahim; Akhaddar, Ali; gazzaz, Miloudi; Boucetta, Mohammed

2014-01-01

Gas production as a part of disc degeneration can occur but rarely causes nerve compression syndromes. The clinical features are similar to those of common sciatica. CT is very useful in the detection of epidural gas accumulation and nerve root compression. We report a case of symptomatic epidural gas accumulation originating from vacuum phenomenon in the intervertebral disc, causing lumbo-sacral radiculopathy. A 45-year-old woman suffered from sciatica for 9 months. The condition worsened in recent days. Computed tomography (CT) demonstrated intradiscal vacuum phenomenon, and accumulation of gas in the lumbar epidural space compressing the dural sac and S1 nerve root. After evacuation of the gas, her pain resolved without recurrence.

Blade Displacement Predictions for the Full-Scale UH-60A Airloads Rotor

NASA Technical Reports Server (NTRS)

Bledron, Robert T.; Lee-Rausch, Elizabeth M.

2014-01-01

An unsteady Reynolds-Averaged Navier-Stokes solver for unstructured grids is loosely coupled to a rotorcraft comprehensive code and used to simulate two different test conditions from a wind-tunnel test of a full-scale UH-60A rotor. Performance data and sectional airloads from the simulation are compared with corresponding tunnel data to assess the level of fidelity of the aerodynamic aspects of the simulation. The focus then turns to a comparison of the blade displacements, both rigid (blade root) and elastic. Comparisons of computed root motions are made with data from three independent measurement systems. Finally, comparisons are made between computed elastic bending and elastic twist, and the corresponding measurements obtained from a photogrammetry system. Overall the correlation between computed and measured displacements was good, especially for the root pitch and lag motions and the elastic bending deformation. The correlation of root lead-lag motion and elastic twist deformation was less favorable.

Severity of foraminal lumbar stenosis and the relation to clinical symptoms and response to periradicular infiltration-introduction of the "melting sign".

PubMed

Farshad, Mazda; Sutter, Reto; Hoch, Armando

2018-02-01

Nerve root compression causing symptomatic radiculopathy can occur within the intervertebral foramen. Sagittal magnetic resonance imaging (MRI) sequences are reliable in detection of nerve root contact to intraforaminal disc material, but a clinically relevant classification of degree of contact is lacking. This study aimed to investigate a potential relation of amount of contact between intraforaminal disc material and nerve root to clinical findings and response after periradicular corticosteroid infiltration. A post hoc analysis of a prospective cohort was carried out. Patients who underwent computed tomography (CT)-guided periradicular corticosteroid infiltration (L1-L5) at our institution (January 2014 to May 2016) were included. The medical records and radiographic imaging were reviewed. T2-weighted MRI of the lumbar spine of patients with single-level symptomatic radiculopathy with (responders, n=28) or without (non-responders, n=14) pain relief after periradicular infiltration with corticosteroids were measured and compared by two independent readers to determine the amount of intraforaminal nerve root contact with the intervertebral disc ("melting" of the T2-hypointense signal). Pain relief was defined with a pain level decrease of >50% on a visual analogue scale and lack of pain relief with a pain level decrease of <25%, respectively. The amount of T2-hypointensity melting of disc and nerve root was categorized to 0%, 1%-25%, and over 25%. Reader one identified 0% T2-melting in none of the responders, 1%-25% melting in 13 patients (46.4%), 26%-50% in 15 of the 28 patients (53.6%) with pain relief after periradicular corticosteroid infiltration (responders), with a mean amount of T2-melting of 5.9±2.1 mm, whereas the non-responder group had 0% T2-melting in 2 patients (14.3%), 1%-25% T2-melting in 11 patients (78.6%), and 26%-50% in 1 patient (7.1%), with a mean amount of T2-melting of 2.6±1.9 mm (p<.05). Reader two identified 0% T2-melting in none, 1%-25% T2-melting in 15 (53.6%) patients, and 26%-50% in 13 of the 28 responders (46.4%), with mean amount of 6.3±1.9 mm. In the non-responder group 0% T2-melting was seen in 3 patients (21.4%), 1%-25% T2-melting in 10 patients (71.4%), and 26%-50% in 1 patient (7.1%), with a mean amount of T2-melting of 2.7±1.9 mm (p<.05). None of the MRI showed T2-melting in over 50% of the circumference of the intraforaminal nerve root. A T2-melting of >25% had a high specificity of 93% but a sensitivity of 50%, thus a positive likelihood ratio of 7.5, to identify those with a pain relief of more than 50% after infiltration. The amount of T2-melting of disc material and nerve root on sagittal MRI (>25%) predicts the amount of pain relief by periradicular infiltration in patients with intraforaminal nerve root irritation. Copyright © 2017 Elsevier Inc. All rights reserved.

Reliability and diagnostic validity of the slump knee bend neurodynamic test for upper/mid lumbar nerve root compression: a pilot study.

PubMed

Trainor, Kate; Pinnington, Mark A

2011-03-01

It has been proposed that neurodynamic examination can assist differential diagnosis of upper/mid lumbar nerve root compression; however, the diagnostic validity of many of these tests has yet to be established. This pilot study aimed to establish the diagnostic validity of the slump knee bend neurodynamic test for upper/mid lumbar nerve root compression in subjects with suspected lumbosacral radicular pain. Two independent examiners performed the slump knee bend test on subjects with radicular leg pain. Inter-tester reliability was calculated using the kappa coefficient. Slump knee bend test results were compared with magnetic resonance imaging findings, and diagnostic accuracy measures were calculated including sensitivity, specificity, predictive values and likelihood ratios. Orthopaedic spinal clinic, secondary care. Sixteen patients with radicular leg pain. All four subjects with mid lumbar nerve root compression on magnetic resonance imaging were correctly identified with the slump knee bend test; however, it was falsely positive in two individuals without the condition. Inter-tester reliability for the slump knee bend test using the kappa coefficient was 0.71 (95% confidence interval 0.33 to 1.0). Diagnostic validity calculations for the slump knee bend test (95% confidence intervals) were: sensitivity, 100% (40 to 100%); specificity, 83% (52 to 98%); positive predictive value, 67% (22 to 96%); negative predictive value, 100% (69 to 100%); positive likelihood ratio, 6.0 (1.58 to 19.4); and negative likelihood ratio, 0 (0 to 0.6). Results indicate good inter-tester reliability and suggest that the slump knee bend test has potential to be a useful clinical test for identifying patients with mid lumbar nerve root compression. Further investigation is needed on larger numbers of patients to confirm these findings. Copyright © 2010 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

Recognizing schwannomatosis and distinguishing it from neurofibromatosis type 1 or 2.

PubMed

Westhout, Franklin D; Mathews, Marlon; Paré, Laura S; Armstrong, William B; Tully, Patricia; Linskey, Mark E

2007-06-01

Schwannomatosis has become a newly recognized classification of neurofibromatosis. Although the genetic loci are on chromosome 22, it lacks the classic bilateral vestibular schwannomas as seen in NF-2. We present the surgical treatment of 4 patients with schwannomatosis, including a brother and sister. Case 1 presented with multiple progressively enlarging peripheral nerve sheath tumors. Case 4 presented with a trigeminal schwannoma and a vagal nerve schwannoma. Three of 4 patients had spinal intradural, extramedullary nerve sheath tumors. Surgery in all was multistaged and consisted of spinal laminectomies, site-specific explorations, and microsurgical tumor dissection and resection, with intraoperative neurophysiologic monitoring (including somatosensory-evoked and motor-evoked potentials, upper extremity electromyography and intraoperative nerve action potential monitoring, as appropriate). Intraoperatively the schwannomas had cystic and solid features and in all surgical cases the tumors arose from discrete fascicles of sensory nerve roots or sensory peripheral nerve branches. None of the patients experienced neurologic worsening as a result of their resections. Pathologic analysis of specimens from all cases demonstrated schwannoma. Not all patients with multiple schwannomas of cranial nerve, spinal nerve root, or peripheral nerve origin have NF-1 or NF-2. In schwannomatosis, these lesions are present in the absence of cutaneous stigmata, neurofibromas, vestibular schwannomas, or parenchymal brain tumors. Schwannomas in schwannomatosis can be large, cystic, and multiple. However, the predominant nerve involvement seems to be sensory and discrete fascicular in origin, facilitating microsurgical resection with minimal deficit.

Residual neurological function after sacral root resection during en-bloc sacrectomy: a systematic review.

PubMed

Zoccali, Carmine; Skoch, Jesse; Patel, Apar S; Walter, Christina M; Maykowski, Philip; Baaj, Ali A

2016-12-01

Sacrectomy is a highly demanding surgery representing the main treatment for primary tumors arising in the sacrum and pelvis. Unfortunately, it is correlated with loss of important function depending on the resection level and nerve roots sacrificed. The current literature regarding residual function after sacral resection comes from several small case series. The goal of this review is to appraise residual motor function and gait, sensitivity, bladder, bowel, and sexual function after sacrectomies, with consideration to the specific roots sacrificed. An exhaustive literature search was conducted. All manuscripts published before May 2015 regarding residual function after sacrectomy were considered; if a clear correlation between root level and functioning was not present, the paper was excluded. The review identified 15 retrospective case series, totaling 244 patients; 42 patients underwent sacrectomies sparing L4/L4, L4/L5 and L5/L5; 45 sparing both L5 and one or both S1 roots; 8 sparing both S1 and one S2; 48 sparing both S2; 11 sparing both S2 and one S3, 54 sparing both S3, 9 sparing both S3 and one or both S4, and 27 underwent unilateral variable resection. Patients who underwent a sacrectomy maintained functionally normal ambulation in 56.2 % of cases when both S2 roots were spared, 94.1 % when both S3 were spared, and in 100 % of more distal resections. Normal bladder and bowel function were not present when both S2 were cut. When one S2 root was spared, normal bladder function was present in 25 % of cases; when both S2 were spared, 39.9 %; when one S3 was spared, 72.7 %; and when both S3 were spared, 83.3 %. Abnormal bowel function was present in 12.5 % of cases when both S1 and one S2 were spared; in 50.0 % of cases when both S2 were spared; and in 70 % of cases when one S3 was spared; if both S3 were spared, bowel function was normal in 94 % of cases. When even one S4 root was spared, normal bladder and bowel function were present in 100 % of cases. Unilateral sacral nerve root resection preserved normal bladder function in 75 % of cases and normal bowel function in 82.6 % of cases. Motor function depended on S1 root involvement. Total sacrectomy is associated with compromising important motor, bladder, bowel, sensitivity, and sexual function. Residual motor function is dependent on sparing L5 and S1 nerve roots. Bladder and bowel function is consistently compromised in higher sacrectomies; nevertheless, the probability of maintaining sufficient function increases progressively with the roots spared, especially when S3 nerve roots are spared. Unilateral resection is usually associated with more normal function. To the best of our knowledge, this is the first comprehensive literature review to analyze published reports of residual sacral nerve root function after sacrectomy.

Diffusion-weighted imaging and diffusion tensor imaging of asymptomatic lumbar disc herniation.

PubMed

Sakai, Toshinori; Miyagi, Ryo; Yamabe, Eiko; Fujinaga, Yasunari; N Bhatia, Nitin; Yoshioka, Hiroshi

2014-01-01

Diffusion-weighted imaging (DWI) and diffusion tensor imaging (DTI) were performed on a healthy 31-year-old man with asymptomatic lumbar disc herniation. Although the left S1 nerve root was obviously entrapped by a herniated mass, neither DWI nor DTI showed any significant findings for the nerve root. Decreased apparent diffusion coefficient (ADC) values and increased fractional anisotropy (FA) values were found. These results are contrary to those in previously published studies of symptomatic patients, in which a combination of increased ADC and decreased FA seem to have a relationship with nerve injury and subsequent symptoms, such as leg pain or palsy. Our results seen in an asymptomatic subject suggest that the compressed nerve with no injury, such as edema, demyelination, or persistent axonal injury, may be indicated by a combination of decreased ADC and increased FA. ADC and FA could therefore be potential tools to elucidate the pathomechanism of radiculopathy.

Identifying motor and sensory myelinated axons in rabbit peripheral nerves by histochemical staining for carbonic anhydrase and cholinesterase activities

NASA Technical Reports Server (NTRS)

Riley, Danny A.; Sanger, James R.; Matloub, Hani S.; Yousif, N. John; Bain, James L. W.

1988-01-01

Carbonic anhydrase (CA) and cholinesterase (CE) histochemical staining of rabbit spinal nerve roots and dorsal root ganglia demonstrated that among the reactive myeliated axons, with minor exceptions, sensory axons were CA positive and CE negative whereas motor axons were CA negative and CE positive. The high specificity was achieved by adjusting reaction conditions to stain subpopulations of myelinated axons selectively while leaving 50 percent or so unstained. Fixation with glutaraldehyde appeared necessary for achieving selectivity. Following sciatic nerve transection, the reciprocal staining pattern persisted in damaged axons and their regenerating processes which formed neuromas within the proximal nerve stump. Within the neuromas, CA-stained sensory processes were elaborated earlier and in greater numbers than CE-stained regenerating motor processes. The present results indicate that histochemical axon typing can be exploited to reveal heterogeneous responses of motor and sensory axons to injury.

Preauricular transmasseteric anteroparotid approach for extracorporeal fixation of mandibular condyle fractures.

PubMed

Gali, Rajasekhar; Devireddy, Sathya Kumar; Venkata, Kishore Kumar Rayadurgam; Kanubaddy, Sridhar Reddy; Nemaly, Chaithanyaa; Dasari, Mallikarjuna

2016-01-01

Free grafting or extracorporeal fixation of traumatically displaced mandibular condyles is sometimes required in patients with severe anteromedial displacement of condylar head. Majority of the published studies report the use of a submandibular, retromandibular or preauricular incisions for the access which have demerits of limited visibility, access and potential to cause damage to facial nerve and other parotid gland related complications. This retrospective clinical case record study was done to evaluate the preauricular transmasseteric anteroparotid (P-TMAP) approach for open reduction and extracorporeal fixation of displaced and dislocated high condylar fractures of the mandible. This retrospective study involved search of clinical case records of seven patients with displaced and dislocated high condylar fractures treated by open reduction and extracorporeal fixation over a 3-year period. The parameters assessed were as follows: a) the ease of access for retrieval, reimplantation and fixation of the proximal segment; b) the postoperative approach related complications; c) the adequacy of anatomical reduction and stability of fixation; d) the occlusal changes; and the e) TMJ function and radiological changes. Accessibility and visibility were good. Accurate anatomical reduction and fixation were achieved in all the patients. The recorded complications were minimal and transient. Facial nerve (buccal branch) palsy was noted in one patient with spontaneous resolution within 3 months. No cases of sialocele or Frey's syndrome were seen. The P-TMAP approach provides good access for open reduction and extracorporeal fixation of severely displaced condylar fractures. It facilitates retrieval, transplantation, repositioning, fixing the condyle and also reduces the chances of requirement of a vertical ramus osteotomy. It gives straight-line access to condylar head and ramus thereby permitting perpendicular placement of screws with minimal risk of damage to the facial nerve.

Preauricular transmasseteric anteroparotid approach for extracorporeal fixation of mandibular condyle fractures

PubMed Central

Gali, Rajasekhar; Devireddy, Sathya Kumar; Venkata, Kishore Kumar Rayadurgam; Kanubaddy, Sridhar Reddy; Nemaly, Chaithanyaa; Dasari, Mallikarjuna

2016-01-01

Introduction: Free grafting or extracorporeal fixation of traumatically displaced mandibular condyles is sometimes required in patients with severe anteromedial displacement of condylar head. Majority of the published studies report the use of a submandibular, retromandibular or preauricular incisions for the access which have demerits of limited visibility, access and potential to cause damage to facial nerve and other parotid gland related complications. Purpose: This retrospective clinical case record study was done to evaluate the preauricular transmasseteric anteroparotid (P-TMAP) approach for open reduction and extracorporeal fixation of displaced and dislocated high condylar fractures of the mandible. Patients and Methods: This retrospective study involved search of clinical case records of seven patients with displaced and dislocated high condylar fractures treated by open reduction and extracorporeal fixation over a 3-year period. The parameters assessed were as follows: a) the ease of access for retrieval, reimplantation and fixation of the proximal segment; b) the postoperative approach related complications; c) the adequacy of anatomical reduction and stability of fixation; d) the occlusal changes; and the e) TMJ function and radiological changes. Results: Accessibility and visibility were good. Accurate anatomical reduction and fixation were achieved in all the patients. The recorded complications were minimal and transient. Facial nerve (buccal branch) palsy was noted in one patient with spontaneous resolution within 3 months. No cases of sialocele or Frey's syndrome were seen. Conclusion: The P-TMAP approach provides good access for open reduction and extracorporeal fixation of severely displaced condylar fractures. It facilitates retrieval, transplantation, repositioning, fixing the condyle and also reduces the chances of requirement of a vertical ramus osteotomy. It gives straight-line access to condylar head and ramus thereby permitting perpendicular placement of screws with minimal risk of damage to the facial nerve. PMID:27274123

Blood-nerve barrier: distribution of anionic sites on the endothelial plasma membrane and basal lamina of dorsal root ganglia.

PubMed

Bush, M S; Reid, A R; Allt, G

1991-09-01

Previous investigations of the blood-nerve barrier have correlated the greater permeability of ganglionic endoneurial vessels, compared to those of nerve trunks, with the presence of fenestrations and open intercellular junctions. Recent studies have demonstrated reduced endothelial cell surface charge in blood vessels showing greater permeability. To determine the distribution of anionic sites on the plasma membranes and basal laminae of endothelial cells in dorsal root ganglia, cationic colloidal gold and cationic ferritin were used. Electron microscopy revealed the existence of endothelial microdomains with differing labelling densities. Labelling indicated that caveolar and fenestral diaphragms and basal laminae are highly anionic at physiological pH, luminal plasma membranes and endothelial processes are moderately charged and abluminal plasma membranes are weakly anionic. Tracers did not occur in caveolae or cytoplasmic vesicles. In vitro tracer experiments at pH values of 7.3, 5.0, 3.5 and 2.0 indicated that the anionic charge on the various endothelial domains was contributed by chemical groups with differing pKa values. In summary, the labelling of ganglionic and sciatic nerve vessels was similar except for the heavy labelling of diaphragms in a minority of endoneurial vessels in ganglia. This difference is likely to account in part for the greater permeability of ganglionic endoneurial vessels. The results are discussed with regard to the blood-nerve and -brain barriers and vascular permeability in other tissues and a comparison made between the ultrastructure and anionic microdomains of epi-, peri- and endoneurial vessels of dorsal root ganglia and sciatic nerves.

Coronectomy versus surgical removal of the lower third molars with a high risk of injury to the inferior alveolar nerve. A bibliographical review

PubMed Central

Moreno-Vicente, Javier; Schiavone-Mussano, Rocío; Clemente-Salas, Enrique; Marí-Roig, Antoni; Jané-Salas, Enric

2015-01-01

Background Coronectomy is the surgical removal of the crown of the tooth deliberately leaving part of its roots. This is done with the hope of eliminating the pathology caused, and since the roots are still intact, the integrity of the inferior alveolar nerve is preserved. Objectives The aim is to carry out a systematic review in order to be able to provide results and conclusions with the greatest scientific evidence possible. Material and Methods A literature review is carried out through the following search engines: Pubmed MEDLINE, Scielo, Cochrane library and EMI. The level of evidence criteria from the Agency for Healthcare Research and Quality was applied, and the clinical trials’ level of quality was analyzed by means of the JADAD criteria. Results The following articles were obtained which represents a total of 17: 1 systematic review, 2 randomized clinical trials and 2 non-randomized clinical trials, 3 cohort studies, 2 retrospective studies, 3 case studies and 4 literature reviews. Conclusions Coronectomy is an adequate preventative technique in protecting the inferior alveolar nerve, which is an alternative to the conventional extraction of third molars, which unlike the former technique, presents a high risk of injury to the inferior alveolar nerve. However, there is a need for new clinical studies, with a greater number of samples and with a longer follow-up period in order to detect potential adverse effects of the retained roots. Key words: Coronectomy, inferior alveolar nerve, nerve injury, wisdom tooth removal, paresthesia, and systematic review. PMID:25858081

Preconditioning crush increases the survival rate of motor neurons after spinal root avulsion

PubMed Central

Li, Lin; Zuo, Yizhi; He, Jianwen

2014-01-01

In a previous study, heat shock protein 27 was persistently upregulated in ventral motor neurons following nerve root avulsion or crush. Here, we examined whether the upregulation of heat shock protein 27 would increase the survival rate of motor neurons. Rats were divided into two groups: an avulsion-only group (avulsion of the L4 lumbar nerve root only) and a crush-avulsion group (the L4 lumbar nerve root was crushed 1 week prior to the avulsion). Immunofluorescent staining revealed that the survival rate of motor neurons was significantly greater in the crush-avulsion group than in the avulsion-only group, and this difference remained for at least 5 weeks after avulsion. The higher neuronal survival rate may be explained by the upregulation of heat shock protein 27 expression in motor neurons in the crush-avulsion group. Furthermore, preconditioning crush greatly attenuated the expression of nitric oxide synthase in the motor neurons. Our findings indicate that the neuroprotective action of preconditioning crush is mediated through the upregulation of heat shock protein 27 expression and the attenuation of neuronal nitric oxide synthase upregulation following avulsion. PMID:25206852

Dermatomal somatosensory evoked potential demonstration of nerve root decompression after VAX-D therapy.

PubMed

Naguszewski, W K; Naguszewski, R K; Gose, E E

2001-10-01

Reductions in low back pain and referred leg pain associated with a diagnosis of herniated disc, degenerative disc disease or facet syndrome have previously been reported after treatment with a VAX-D table, which intermittently distracts the spine. The object of this study was to use dermatomal somatosensory evoked potentials (DSSEPs) to demonstrate lumbar root decompression following VAX-D therapy. Seven consecutive patients with a diagnosis of low back pain and unilateral or bilateral L5 or S1 radiculopathy were studied at our center. Disc herniation at the L5-S1 level was documented by MRI or CT in all patients. All patients were studied bilaterally by DSSEPs at L5 and S1 before and after VAX-D therapy. All patients had at least 50% improvement in radicular symptoms and low back pain and three of them experienced complete resolution of all symptoms. The average pain reduction was 77%. The number of treatment sessions varied from 12 to 35. DSSEPs were considered to show improvement if triphasic characteristics returned or a 50% or greater increase in the P1-P2 amplitude was seen. All patients showed improvement in DSSEPs after VAX-D therapy either ipsilateral or contralateral to the symptomatic leg. Two patients showed deterioration in DSSEPs in the symptomatic leg despite clinically significant improvement in pain and radicular symptoms. Overall, 28 nerve roots were studied before and after VAX-D therapy. Seventeen nerve root responses were improved, eight remained unchanged and three deteriorated. The significance of DSSEP improvement contralateral to the symptomatic leg is emphasized. Direct compression of a nerve root by a disc herniation is probably not the sole explanation for referred leg pain.

Coronectomy of Deeply Impacted Lower Third Molar: Incidence of Outcomes and Complications after One Year Follow-Up

PubMed Central

Heijsters, Guido; Salem, Ahmed Sobhy; Van Slycke, Sarah; Schepers, Serge; Politis, Constantinus; Vrielinck, Luc

2015-01-01

ABSTRACT Objectives The purpose of present study was to assess the surgical management of impacted third molar with proximity to the inferior alveolar nerve and complications associated with coronectomy in a series of patients undergoing third molar surgery. Material and Methods The position of the mandibular canal in relation to the mandibular third molar region and mandibular foramen in the front part of the mandible (i.e., third molar in close proximity to the inferior alveolar nerve [IAN] or not) was identified on panoramic radiographs of patients scheduled for third molar extraction. Results Close proximity to the IAN was observed in 64 patients (35 females, 29 males) with an impacted mandibular third molar. Coronectomy was performed in these patients. The most common complication was tooth migration away from the mandibular canal (n = 14), followed by root exposure (n = 5). Re-operation to remove the root was performed in cases with periapical infection and root exposure. Conclusions The results indicate that coronectomy can be considered a reasonable and safe treatment alternative for patients who demonstrate elevated risk for injury to the inferior alveolar nerve with removal of the third molars. Coronectomy did not increase the incidence of damage to the inferior alveolar nerve and would be safer than complete extraction in situations in which the root of the mandibular third molar overlaps or is in close proximity to the mandibular canal. PMID:26229580

Response of cervicogenic headaches and occipital neuralgia to radiofrequency ablation of the C2 dorsal root ganglion and/or third occipital nerve.

PubMed

Hamer, John F; Purath, Traci A

2014-03-01

This article investigates the degree and duration of pain relief from cervicogenic headaches or occipital neuralgia following treatment with radiofrequency ablation of the C2 dorsal root ganglion and/or third occipital nerves. It also addresses the procedure's complication rate and patient's willingness to repeat the procedure if severe symptoms recur. This is a single-center retrospective observational study of 40 patients with refractory cervicogenic headaches and or occipital neuralgia. Patients were all referred by a headache specialty clinic for evaluation for radiofrequency ablation of the C2 dorsal root ganglion and/or third occipital nerves. After treatment, patients were followed for a minimum of 6 months to a year. Patient demographics and the results of radiofrequency ablation were recorded on the same day, after 3-4 days, and at 6 months to 1 year following treatment. Thirty-five percent of patients reported 100% pain relief and 70% reported 80% or greater pain relief. The mean duration of improvement is 22.35 weeks. Complication rate was 12-13%. 92.5% of patients reported they would undergo the procedure again if severe symptoms returned. Radiofrequency ablation of the C2 dorsal root ganglion and/or third occipital nerve can provide many months of greater than 50% pain relief in the vast majority of recipients with an expected length of symptom improvement of 5-6 months. © 2014 American Headache Society.

Trigeminal nerve anatomy in neuropathic and non-neuropathic orofacial pain patients.

PubMed

Wilcox, Sophie L; Gustin, Sylvia M; Eykman, Elizabeth N; Fowler, Gordon; Peck, Christopher C; Murray, Greg M; Henderson, Luke A

2013-08-01

Trigeminal neuralgia, painful trigeminal neuropathy, and painful temporomandibular disorders (TMDs) are chronic orofacial pain conditions that are thought to have fundamentally different etiologies. Trigeminal neuralgia and neuropathy are thought to arise from damage to or pressure on the trigeminal nerve, whereas TMD results primarily from peripheral nociceptor activation. This study sought to assess the volume and microstructure of the trigeminal nerve in these 3 conditions. In 9 neuralgia, 18 neuropathy, 20 TMD, and 26 healthy controls, the trigeminal root entry zone was selected on high-resolution T1-weighted magnetic resonance images and the volume (mm(3)) calculated. Additionally, using diffusion-tensor images (DTIs), the mean diffusivity and fractional anisotropy values of the trigeminal nerve root were calculated. Trigeminal neuralgia patients displayed a significant (47%) decrease in nerve volume but no change in DTI values. Conversely, trigeminal neuropathy subjects displayed a significant (40%) increase in nerve volume but again no change in DTI values. In contrast, TMD subjects displayed no change in volume or DTI values. The data suggest that the changes occurring within the trigeminal nerve are not uniform in all orofacial pain conditions. These structural and volume changes may have implications in diagnosis and management of different forms of chronic orofacial pain. This study reveals that neuropathic orofacial pain conditions are associated with changes in trigeminal nerve volume, whereas non-neuropathic orofacial pain is not associated with any change in nerve volume. Crown Copyright © 2013. Published by Elsevier Inc. All rights reserved.

[Role of short-latency somatosensory evoked potential in the diagnosis of chronic inflammatory demyelinating polyneuropathy].

PubMed

Sun, Rui-Di; Fu, Bing; Jiang, Jun

2017-05-01

To investigate the role of short-latency somatosensory evoked potential (SSEP) in the diagnosis of chronic inflammatory demyelinating polyneuropathy (CIDP). A total of 48 children with a confirmed or suspected CIDP and 40 healthy children were enrolled. Nerve electrophysiological examination and/or SSEP examination was performed (the children in the healthy control group only underwent SSEP examination). Four-lead electromyography was used for nerve electrophysiological examination, including at least 4 motor nerves and 2 sensory nerves. N6 (elbow potential), N13 (cervical cord potential), and N20 (cortex potential) of the median nerve and N8 (popliteal fossa potential), N22 (lumbar cord potential), and P39 (cortex potential) of the tibial nerve were observed by SSEP examination. Among the 48 children with CIDP, 35 had demyelination in both motor and sensory nerves, 8 had demyelination in sensory nerves, and 5 had axonal degeneration. SSEP examination showed that 7 had conduction abnormality in the trunk of the brachial plexus and/or the posterior root and 33 had damage in the lumbosacral plexus and/or the posterior root. The 40 children with abnormal findings of SSEP examination included 8 children with affected sensory nerves and 5 children with secondary axonal degeneration who did not meet the electrophysiological diagnostic criteria for CIDP. Compared with the healthy control group, the CIDP group had significantly prolonged latency periods of N13 and N22 (P<0.05). SSEP can be used for the auxiliary diagnosis of CIDP, especially in CIDP children with affected sensory nerves or secondary axonal degeneration.

Cochlear Implantation in Patients With CHARGE Syndrome.

PubMed

Rah, Yoon Chan; Lee, Ji Young; Suh, Myung-Whan; Park, Moo Kyun; Lee, Jun Ho; Chang, Sun O; Oh, Seung-Ha

2016-11-01

To determine the optimal surgical approach for cochlear implantation (CI) preoperatively based on the spatial relation of a displaced facial nerve (FN) and middle ear structures and to analyze clinical outcomes of CHARGE syndrome. Facial nerve displacement and associated deviation of inner ear structures were analyzed in 13 patients (17 ears) with CHARGE syndrome who underwent CI. Surgical accessibility through the facial recess was assessed based on anatomical landmarks. Postoperative speech performance and associated clinical characteristics were analyzed. The most consistently identified ear anomalies were semicircular canal aplasia (100%), ossicular anomaly (100%), and vestibular hypoplasia (88%). Facial nerve displacement was found in 77% of cases (anteroinferior: 47%, anterior: 24%, inferior: 6%). The width of available surgical space around facial recess was significantly greater in cases of facial recess approach (2.85 ± 0.9 mm) than those of alternative approach (0.12 ± 0.29 mm, P = .02). Postoperatively, 53% achieved better than category 4 on the categories of auditory perception (CAP) scale. The CAP category was significantly correlated with internal auditory canal diameter (P = .025) and did not differ according to the applied surgical approach. Preoperative determination of surgical accessibility through facial recess would be useful for safe surgical approach, and successful hearing rehabilitation was achievable by applying appropriate surgical approaches. © The Author(s) 2016.

Three lateral divergent or parallel pin fixations for the treatment of displaced supracondylar humerus fractures in children.

PubMed

Lee, Young Ho; Lee, Sang Ki; Kim, Byung Sung; Chung, Moon Sang; Baek, Goo Hyun; Gong, Hyun Sik; Lee, Joon Kyu

2008-06-01

To evaluate the efficacy of lateral or parallel pin fixation using 3 smooth Kirschner wires (K-wires) or smooth Steinmann pins for the operative management of displaced supracondylar humeral fracture in a consecutive series of children. Sixty-one consecutive displaced or angled supracondylar humeral fractures (Gartland type II or III) in children (mean age, 5 years 6 months) treated by 2 orthopaedic surgeons between 2001 and 2004 according to the following protocol: close reduction under general anesthesia with fluoroscopic guidance and only lateral percutaneous pinning using 3 divergent or parallel Kirschner wires or Steinmann pins. Minimum 2 years' follow-up was done in all 61 patients (range, 2.0-3.3 years). Clinical assessment was obtained at final follow-up using Flynn criteria, and radiologic assessment was obtained using the Baumann and lateral humerocapitellar angles of both arms. Statistical analysis was performed by means of the Student t test (P < 0.05). The study group consisted of 61 patients, of whom 24 (39%) presented with Gartland type II fractures, and the remaining 37 (61%) presented with a type III fracture. A comparison of perioperative and final radiographs shows no loss of reduction of any fracture. There was also no clinically evident cubitus varus, hyperextension, or loss of motion. Eight patients had preoperative nerve palsy. Five of these nerve injuries resolved immediately after surgery, and the other 3 resolved completely within 12 weeks of surgery. After an average of 28 months postoperation, 56 (91.8%) patients had achieved an excellent clinical result, and 5 (8.2%) achieved a good result. There were no iatrogenic nerve palsies, and no patient required additional surgery. One patient had a minor pin-track infection. Our series demonstrates that only 3 lateral divergent or parallel pin fixations are effective and safe for avoiding iatrogenic ulnar nerve injury and are appropriate treatment options for displaced or angled supracondylar humeral fractures in children. Therapeutic study, level III.

GRAVI-2 space experiment: investigating statoliths displacement and location effects on early stages of gravity perception pathways in lentil roots.

NASA Astrophysics Data System (ADS)

Bizet, François; Eche, Brigitte; Pereda Loth, Veronica; Badel, Eric; Legue, Valerie; Brunel, Nicole; Label, Philippe; Gérard, Joëlle

2016-07-01

The plants ability to orient their growth with respect to external stimuli such as gravity is a key factor for survival and acclimation to their environment. Belowground, plant roots modulate their growth towards gravity, allowing soil exploration and uptake of water and nutrients. In roots, gravity sensing cells called statocytes are located in the center of the root cap. Statocytes contain starch-filled plastids denser than the cytoplasm, which sedimentation along the direction of gravity is widely accepted as being involved into early stages of gravity perception (the starch-statolith hypothesis; Sack, 1991). Root gravitropism following statoliths displacement is based on auxin redistribution in the root apex, inducing differential growth between the root upward and downward sides. However at the cell scale, the chain of transduction starting from statoliths displacement and leading to auxin redistribution remains poorly documented. Signaling molecules such as calcium, reactive oxygen species, nitric oxide and inositol 1,4,5-triphosphate are serious candidates previously shown to be involved within minutes before modification of the expression of auxin-related genes (Morita, 2010; Sato et al., 2015). Here, we observe and quantify statoliths displacements and locations at various levels of gravity to investigate two hypothesis: (i) Are contacts between statoliths and the endoplasmic reticulum necessary to induce gravitropism? (ii) Are very low displacements of statoliths sufficient to initiate transduction pathways such as the calcium's one? These questionings have led to an experiment called GRAVI-2 which took place aboard the ISS in 2014. During the experiment, lentil roots were grown in the European modular cultivation system for several hours in microgravity and were then submitted to short high gravity stimulus (5 and 15 minutes at 2 g) before the return to Earth for analyses. Ongoing cytological measurements will reveal the effects of statoliths displacement and location on intracellular calcium localization. Complementary RNA sequencing was done and current transcriptomic analyses will show the regulation of calcium-downstream gene expression and of auxin dependent pathways at two short time steps following gravistimulus. In addition, some of the lentil roots grown in microgravity aboard the ISS were submitted for several hours to low level of gravity (10-2 g) close to the detection threshold determined on a previous experiment (GRAVI-1; Driss-Ecole et al., 2008). Root gravitropism in response to such a low level of gravity was investigated and compared to the very low statoliths displacement expected. This study give insights about the molecular mechanisms underlying the very high sensitivity of roots to gravity and are among the firsts studies involving global transcriptomic analyses of root material grown in microgravity. Keywords: Calcium; ISS; Microgravity; Root; Statholith; Transcriptomic Acknowledgments: The authors thank G. Perbal, D. Driss-Ecole, the European space agency and the Norwegian user support and operations center team for their considerable help in the preparation and achievement of the GRAVI experiments. This work should not have been possible without the financial supports of the Centre National d'Etudes Spatiales (CNES) through a postdoctoral fellowship. References: Driss-Ecole, D., Legué, V., Carnero-Diaz, E. and Perbal, G. 2008. Gravisensitivity and automorphogenesis of lentil seedling roots grown on board the International Space Station. Physiologia Plantarum. 134, 1 (2008), 191-201. Morita, M. 2010. Directional Gravity Sensing in Gravitropism. Plant Biology. 61, 1 (2010), 705-720. Sack, F.D. 1991. Plant gravity sensing. International review of cytology. 127, (1991), 193-252. Sato, E.M., Hijazi, H., Bennett, M.J., Vissenberg, K. and Swarup, R. 2015. New insights into root gravitropic signalling. Journal of experimental botany. 66, 8 (Apr. 2015), 2155-65.

Facial nerve injuries associated with the retromandibular transparotid approach for reduction and fixation of mandibular condyle fractures.

PubMed

Shi, Dan; Patil, Pavan Manohar; Gupta, Ritika

2015-04-01

To document facial nerve (FN) injuries after surgical treatment of mandibular condylar fractures using the retromandibular transparotid approach and to identify risk factors associated with these injuries. A retrospective study of patients surgically treated for mandibular condylar fractures using the retromandibular transparotid approach over seven years was conducted. The primary study variable was the postoperative change in FN function after fracture fixation. Risk factors were categorized as demographic, anatomic, experience of the operator, fracture displacement/dislocation and number of miniplates placed at the fracture site. Appropriate statistics were computed. Ninety patients with 102 fractures were analysed. Thirty two fractures (31%) were located in the condylar neck and 70 fractures (69%) were subcondylar (located below the sigmoid notch). The condylar segment was undisplaced in twelve cases (12%), displaced medially in thirty five (34%), laterally displaced in thirty (29%) and dislocated in 25 (24.5%). In 18 fractures (18%), postoperative examination revealed various degrees of damage to the FN. All nerve injuries recovered completely in 8-24 weeks. In a multivariate model, condylar neck fractures, fracture dislocation and operator inexperience were associated with a statistically significant risk of postoperative deterioration of FN function (P ≤ 0.05). The majority of facial nerve injuries after surgical treatment of condylar fractures by the retromandibular transparotid approach are transient in nature. Condylar neck fractures, fracture dislocation and operator inexperience were associated with an increased risk for FN injury. Copyright © 2014 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Macrovascular Decompression of the Brainstem and Cranial Nerves: Evolution of an Anteromedial Vertebrobasilar Artery Transposition Technique.

PubMed

Choudhri, Omar; Connolly, Ian D; Lawton, Michael T

2017-08-01

Tortuous and dolichoectatic vertebrobasilar arteries can impinge on the brainstem and cranial nerves to cause compression syndromes. Transposition techniques are often required to decompress the brainstem with dolichoectatic pathology. We describe our evolution of an anteromedial transposition technique and its efficacy in decompressing the brainstem and relieving symptoms. To present the anteromedial vertebrobasilar artery transposition technique for macrovascular decompression of the brainstem and cranial nerves. All patients who underwent vertebrobasilar artery transposition were identified from the prospectively maintained database of the Vascular Neurosurgery service, and their medical records were reviewed retrospectively. The extent of arterial displacement was measured pre- and postoperatively on imaging. Vertebrobasilar arterial transposition and macrovascular decompression was performed in 12 patients. Evolution in technique was characterized by gradual preference for the far-lateral approach, use of a sling technique with muslin wrap, and an anteromedial direction of pull on the vertebrobasilar artery with clip-assisted tethering to the clival dura. With this technique, mean lateral displacement decreased from 6.6 mm in the first half of the series to 3.8 mm in the last half of the series, and mean anterior displacement increased from 0.8 to 2.5 mm, with corresponding increases in satisfaction and relief of symptoms. Compressive dolichoectatic pathology directed laterally into cranial nerves and posteriorly into the brainstem can be corrected with anteromedial transposition towards the clivus. Our technique accomplishes this anteromedial transposition from an inferolateral surgical approach through the vagoaccessory triangle, with sling fixation to clival dura using aneurysm clips. Copyright © 2017 by the Congress of Neurological Surgeons

[Anatomical rationale for lingual nerve injury prevention during mandibular block].

PubMed

Semkin, V A; Dydikin, S S; Kuzin, A V; Sogacheva, V V

2015-01-01

The topographic and anatomical study of lingual nerve structural features was done. It was revealed that during mandibular anesthesia possible lingual nerve injury can occur if puncture needle is lower than 1 cm. of molars occlusal surface level. The position of the lingual nerve varies withmandible movements. At the maximum open mouth lingual nerve is not mobile and is pressed against the inner surface of the mandibular ramus by the medial pterygoid muscle and the temporal muscle tendon. When closing the mouth to 1.25±0.2 cmfrom the physiological maximum, lingual nerve is displaced posteriorly from the internal oblique line of the mandible and gets mobile. On the basis of topographic and anatomic features of the lingual nervestructure the authors recommend the re-do of inferior alveolar nerve block, a semi-closed mouth position or the use the "high block techniques" (Torus anesthesia, Gow-Gates, Vazirani-Akinozi).

Transposition of branches of radial nerve innervating supinator to posterior interosseous nerve for functional reconstruction of finger and thumb extension in 4 patients with middle and lower trunk root avulsion injuries of brachial plexus.

PubMed

Wu, Xia; Cong, Xiao-Bing; Huang, Qi-Shun; Ai, Fang-Xin; Liu, Yu-Tian; Lu, Xiao-Cheng; Li, Jin; Weng, Yu-Xiong; Chen, Zhen-Bing

2017-12-01

This study aimed to investigate the reconstruction of the thumb and finger extension function in patients with middle and lower trunk root avulsion injuries of the brachial plexus. From April 2010 to January 2015, we enrolled in this study 4 patients diagnosed with middle and lower trunk root avulsion injuries of the brachial plexus via imaging tests, electrophysiological examinations, and clinical confirmation. Muscular branches of the radial nerve, which innervate the supinator in the forearm, were transposed to the posterior interosseous nerve to reconstruct the thumb and finger extension function. Electrophysiological findings and muscle strength of the extensor pollicis longus and extensor digitorum communis, as well as the distance between the thumb tip and index finger tip, were monitored. All patients were followed up for 24 to 30 months, with an average of 27.5 months. Motor unit potentials (MUP) of the extensor digitorum communis appeared at an average of 3.8 months, while MUP of the extensor pollicis longus appeared at an average of 7 months. Compound muscle action potential (CMAP) appeared at an average of 9 months in the extensor digitorum communis, and 12 months in the extensor pollicis longus. Furthermore, the muscle strength of the extensor pollicis longus and extensor digitorum communis both reached grade III at 21 months. Lastly, the average distance between the thumb tip and index finger tip was 8.8 cm at 21 months. In conclusion, for patients with middle and lower trunk injuries of the brachial plexus, transposition of the muscular branches of the radial nerve innervating the supinator to the posterior interosseous nerve for the reconstruction of thumb and finger extension function is practicable and feasible.

Efficacy of intraoperative monitoring of transcranial electrical stimulation-induced motor evoked potentials and spontaneous electromyography activity to identify acute-versus delayed-onset C-5 nerve root palsy during cervical spine surgery: clinical article.

PubMed

Bhalodia, Vidya M; Schwartz, Daniel M; Sestokas, Anthony K; Bloomgarden, Gary; Arkins, Thomas; Tomak, Patrick; Gorelick, Judith; Wijesekera, Shirvinda; Beiner, John; Goodrich, Isaac

2013-10-01

Deltoid muscle weakness due to C-5 nerve root injury following cervical spine surgery is an uncommon but potentially debilitating complication. Symptoms can manifest upon emergence from anesthesia or days to weeks following surgery. There is conflicting evidence regarding the efficacy of spontaneous electromyography (spEMG) monitoring in detecting evolving C-5 nerve root compromise. By contrast, transcranial electrical stimulation-induced motor evoked potential (tceMEP) monitoring has been shown to be highly sensitive and specific in identifying impending C-5 injury. In this study the authors sought to 1) determine the frequency of immediate versus delayed-onset C-5 nerve root injury following cervical spine surgery, 2) identify risk factors associated with the development of C-5 palsies, and 3) determine whether tceMEP and spEMG neuromonitoring can help to identify acutely evolving C-5 injury as well as predict delayed-onset deltoid muscle paresis. The authors retrospectively reviewed the neuromonitoring and surgical records of all patients who had undergone cervical spine surgery involving the C-4 and/or C-5 level in the period from 2006 to 2008. Real-time tceMEP and spEMG monitoring from the deltoid muscle was performed as part of a multimodal neuromonitoring protocol during all surgeries. Charts were reviewed to identify patients who had experienced significant changes in tceMEPs and/or episodes of neurotonic spEMG activity during surgery, as well as those who had shown new-onset deltoid weakness either immediately upon emergence from the anesthesia or in a delayed fashion. Two hundred twenty-nine patients undergoing 235 cervical spine surgeries involving the C4-5 level served as the study cohort. The overall incidence of perioperative C-5 nerve root injury was 5.1%. The incidence was greatest (50%) in cases with dual corpectomies at the C-4 and C-5 spinal levels. All patients who emerged from anesthesia with deltoid weakness had significant and unresolved changes in tceMEPs during surgery, whereas only 1 had remarkable spEMG activity. Sensitivity and specificity of tceMEP monitoring for identifying acute-onset deltoid weakness were 100% and 99%, respectively. By contrast, sensitivity and specificity for spEMG were only 20% and 92%, respectively. Neither modality was effective in identifying patients who demonstrated delayed-onset deltoid weakness. The risk of new-onset deltoid muscle weakness following cervical spine surgery is greatest for patients undergoing 2-level corpectomies involving C-4 and C-5. Transcranial electrical stimulation-induced MEP monitoring is a highly sensitive and specific technique for detecting C-5 radiculopathy that manifests immediately upon waking from anesthesia. While the absence of sustained spEMG activity does not rule out nerve root irritation, the presence of excessive neurotonic discharges serves both to alert the surgeon of such potentially injurious events and to prompt neuromonitoring personnel about the need for additional tceMEP testing. Delayed-onset C-5 nerve root injury cannot be predicted by intraoperative neuromonitoring via either modality.

Abnormal flexor carpi radialis H-reflex as a specific indicator of C7 as compared with C6 radiculopathy.

PubMed

Zheng, Chaojun; Zhu, Yu; Lv, Feizhou; Ma, Xiaosheng; Xia, Xinlei; Wang, Lixun; Jin, Xiang; Weber, Robert; Jiang, Jianyuan; Anuvat, Kevin

2014-12-01

The H-reflex of the flexor carpi radialis (FCR H-reflex) has not been commonly used for the diagnosis of cervical radiculopathy when compared with the routinely tested soleus H-reflex. Although both S1 and S2 roots innervate the soleus, the H-reflex is selectively related to S1 nerve root function clinically. Flexor carpi radialis is also innervated by two nerve roots which are C6 and C7. Although they are among the most common roots involved in cervical radiculopathy, few studies reported if the attenuation of the FCR H-reflex is caused by lesions affecting C7 or C6 nerve roots, or both. We aimed to identify whether an abnormal FCR H-reflex was attributed to the C7 or C6 nerve root lesion, or both. The sensitivities of needle electromyography, FCR H-reflex, and provocative tests in unilateral C7 or C6 radiculopathy were also compared in this study. A concentric needle electrode recorded bilateral FCR H-reflexes in 41 normal subjects (control group), 51 patients with C7 radiculopathy, and 54 patients with C6 radiculopathy. Clinical, radiological, and surgical approaches identified the precise single cervical nerve root involved in all patient groups. The H-reflex and M-wave latencies were measured and compared bilaterally. Abnormal FCR H-reflex was defined as the absence of the H-reflex or a side-to-side difference over 1.5 milliseconds which was based on the normal side-to-side difference of the H-reflex latency of 16.9 milliseconds (SD = 1.7 milliseconds) from the control group. We also determined standard median and ulnar conduction and needle electromyography. The provocative tests included bilateral determination of the Shoulder Abduction and Spurling's tests in all radiculopathy group patients. Abnormal FCR H-reflexes were recorded in 45 (88.2%) of C7 radiculopathy group patients, and 2 (3.7%) of C6 radiculopathy group patients (P < 0.05). Needle electromyography was abnormal in 41 (80.4%) of C7 radiculopathy patients and 43 (79.6%) of C6 radiculopathy patients. Provocative tests were positive in 15 (29.4%) of C7 radiculopathy patients and 25 (46.3%) of C6 radiculopathy patients. Flexor carpi radialis H-Reflex provides a sensitive assessment of evaluating the C7 spinal reflex pathway. Clinically, a combination of the FCR H-reflex with needle electromyography may yield the highest level of diagnostic information for evaluating clinical cases of C7 radiculopathy.

Clinical course, characteristics and prognostic indicators in patients presenting with back and leg pain in primary care. The ATLAS study protocol

PubMed Central

2012-01-01

Background Low-back related leg pain with or without nerve root involvement is associated with a poor prognosis compared to low back pain (LBP) alone. Compared to the literature investigating prognostic indicators of outcome for LBP, there is limited evidence on prognostic factors for low back-related leg pain including the group with nerve root pain. This 1 year prospective consultation-based observational cohort study will describe the clinical, imaging, demographic characteristics and health economic outcomes for the whole cohort, will investigate differences and identify prognostic indicators of outcome (i.e. change in disability at 12 months), for the whole cohort and, separately, for those classified with and without nerve root pain. In addition, nested qualitative studies will provide insights on the clinical consultation and the impact of diagnosis and treatment on patients' symptom management and illness trajectory. Methods Adults aged 18 years and over consulting their General Practitioner (GP) with LBP and radiating leg pain of any duration at (n = 500) GP practices in North Staffordshire and Stoke-on-Trent, UK will be invited to participate. All participants will receive a standardised assessment at the clinic by a study physiotherapist and will be classified according to the clinically determined presence or absence of nerve root pain/involvement. All will undergo a lumbar spine MRI scan. All participants will be managed according to their clinical need. The study outcomes will be measured at 4 and 12 months using postal self-complete questionnaires. Data will also be collected each month using brief postal questionnaires to enable detailed description of the course of low back and leg pain over time. Clinical observations and patient interviews will be used for the qualitative aspects of the study. Discussion This prospective clinical observational cohort will combine self-reported data, comprehensive clinical and MRI assessment, together with qualitative enquiries, to describe the course, health care usage, patients' experiences and prognostic indicators in an adult population presenting in primary care with LBP and leg pain with or without nerve root involvement. PMID:22264273

Anatomical relationship between mental foramen, mandibular teeth and risk of nerve injury with endodontic treatment.

PubMed

Chong, Bun San; Gohil, Kajal; Pawar, Ravikiran; Makdissi, Jimmy

2017-01-01

The objective of the present study was to evaluate the anatomical relationship between mental foramen (MF), including the incidence of the anterior loop of the inferior alveolar nerve (AL), and roots of mandibular teeth in relation to risk of nerve injury with endodontic treatment. Cone-beam computed tomography (CBCT) images, which included teeth either side of the MF, were randomly selected. The anonymised CBCT images were reconstructed and examined in coronal, axial and sagittal planes, using three-dimensional viewing software, to determine the relationship and distance between MF and adjacent mandibular teeth. The actual distance between the root apex and MF was calculated mathematically using Pythagoras' theorem. If present, the incidence of an AL in the axial plane was also recorded. The root apex of the mandibular second premolar (70 %), followed by the first premolar (18 %) and then the first molar (12 %), was the closest to the MF. Ninety-six percent of root apices evaluated were >3 mm from the MF. An AL was present in 88 % of the cases. With regards to endodontic treatment, the risk of nerve injury in the vicinity of the MF would appear to be low. However, the high incidence of the AL highlights the need for clinicians to be aware and careful of this important anatomical feature. The risk of injury to the MN with endodontic treatment would appear to be low, but given the high incidence, it is important to be aware and be careful of the AL.

Axon-Sorting Multifunctional Nerve Guides: Accelerating Restoration of Nerve Function

DTIC Science & Technology

2014-10-01

factor (singly & in selected combinations) in the organotypic model system for preferential sensory or motor axon extension. Use confocal microscopy to...track axon extension of labeled sensory or motor neurons from spinal cord slices (motor) or dorsal root ganglia ( DRG ) (sensory). 20 Thy1-YFP mice...RESEARCH ACCOMPLISHMENTS: • Established a system of color-coded mixed nerve tracking using GFP and RFP expressing motor and sensory neurons (Figure 1

Effects of medial meniscal posterior horn avulsion and repair on meniscal displacement.

PubMed

Hein, Christopher N; Deperio, Jennifer Gurske; Ehrensberger, Mark T; Marzo, John M

2011-06-01

Medial meniscal posterior root avulsion (MMRA) leads to deleterious alteration of medial joint compartment loading profiles and increased risk of medial degenerative changes. Surgical repair restores more normal biomechanics to the knee. Our hypothesis is that MMRA will cause medial meniscal (MM) extrusion and gap formation between the root attachment site and MM. Meniscal root repair will restore the ability of the meniscus to resist extrusion, and reduce gap formation at the defect. Seven fresh frozen human cadaveric knees were dissected and mechanically loaded using a servo-hydraulic load frame (MTS ®) with 0 and 1800 N. The knees were tested under three conditions: native, avulsed, and repaired. Four measurements were obtained: meniscal displacement anteriorly, medially, posteriorly, and gap distance between the root attachment site and MM after transection and repair. The medial displacement of the avulsed MM (3.28 mm) was significantly greater (p < 0.001) than the native knee (1.60mm) and repaired knee (1.46 mm). Gap formation is significantly larger in the avulsed compared to repaired state at 0 (p < 0.02) and 1800N (p < 0.02) and also larger with loading in both avulsed (p < 0.05) and repaired (p < 0.02) conditions. Therefore, MMRA results in MM extrusion from the joint and gap formation between the MM root and the MM. Subsequent surgical repair reduces meniscal displacement and gap formation at the defect. Copyright © 2010 Elsevier B.V. All rights reserved.

Primary olfactory projections and the nervus terminalis in the African lungfish: implications for the phylogeny of cranial nerves.

PubMed

von Bartheld, C S; Claas, B; Münz, H; Meyer, D L

1988-08-01

Primary olfactory and central projections of the nervus terminalis were investigated by injections of horseradish peroxidase into the olfactory epithelium in the African lungfish. In addition, gonadotropin-releasing hormone (GnRH) immunoreactivity of the nervus terminalis system was investigated. The primary olfactory projections are restricted to the olfactory bulb located at the rostral pole of the telencephalon; they do not extend into caudal parts of the telencephalon. A vomeronasal nerve and an accessory olfactory bulb could not be identified. The nervus terminalis courses through the dorsomedial telencephalon. Major targets include the nucleus of the anterior commissure and the nucleus praeopticus pars superior. some fibers cross to the contralateral side. A few fibers reach the diencephalon and mesencephalon. No label is present in the "posterior root of the nervus terminalis" (= "Pinkus's nerve" or "nervus praeopticus"). GnRH immunoreactivity is lacking in the "anterior root of the nervus terminalis," whereas it is abundant in nervus praeopticus (Pinkus's nerve). These findings may suggest that the nervus terminalis system originally consisted of two distinct cranial nerves, which have fused-in evolution-in most vertebrates. Theories of cranial nerve phylogeny are discussed in the light of the assumed "binerval origin" of the nervus terminalis system.

Progranulin contributes to endogenous mechanisms of pain defense after nerve injury in mice.

PubMed

Lim, Hee-Young; Albuquerque, Boris; Häussler, Annett; Myrczek, Thekla; Ding, Aihao; Tegeder, Irmgard

2012-04-01

Progranulin haploinsufficiency is associated with frontotemporal dementia in humans. Deficiency of progranulin led to exaggerated inflammation and premature aging in mice. The role of progranulin in adaptations to nerve injury and neuropathic pain are still unknown. Here we found that progranulin is up-regulated after injury of the sciatic nerve in the mouse ipsilateral dorsal root ganglia and spinal cord, most prominently in the microglia surrounding injured motor neurons. Progranulin knockdown by continuous intrathecal spinal delivery of small interfering RNA after sciatic nerve injury intensified neuropathic pain-like behaviour and delayed the recovery of motor functions. Compared to wild-type mice, progranulin-deficient mice developed more intense nociceptive hypersensitivity after nerve injury. The differences escalated with aging. Knockdown of progranulin reduced the survival of dissociated primary neurons and neurite outgrowth, whereas addition of recombinant progranulin rescued primary dorsal root ganglia neurons from cell death induced by nerve growth factor withdrawal. Thus, up-regulation of progranulin after neuronal injury may reduce neuropathic pain and help motor function recovery, at least in part, by promoting survival of injured neurons and supporting regrowth. A deficiency in this mechanism may increase the risk for injury-associated chronic pain. © 2011 The Authors Journal of Cellular and Molecular Medicine © 2011 Foundation for Cellular and Molecular Medicine/Blackwell Publishing Ltd.

Apical root resorption in orthodontically treated adults.

PubMed

Baumrind, S; Korn, E L; Boyd, R L

1996-09-01

This study analyzed the relationship in orthodontically treated adults between upper central incisor displacement measured on lateral cephalograms and apical root resorption measured on anterior periapical x-ray films. A multiple linear regression examined incisor displacements in four directions (retraction, advancement, intrusion, and extrusion) as independent variables, attempting to account for observed differences in the dependent variable, resorption. Mean apical resorption was 1.36 mm (sd +/- 1.46, n = 73). Mean horizontal displacement of the apex was -0.83 mm (sd +/- 1.74, n = 67); mean vertical displacement was 0.19 mm (sd +/- 1.48, n = 67). The regression coefficients for the intercept and for retraction were highly significant; those for extrusion, intrusion, and advancement were not. At the 95% confidence level, an average of 0.99 mm (se = +/- 0.34) of resorption was implied in the absence of root displacement and an average of 0.49 mm (se = +/- 0.14) of resorption was implied per millimeter of retraction. R2 for all four directional displacement variables (DDVs) taken together was only 0.20, which implied that only a relatively small portion of the observed apical resorption could be accounted for by tooth displacement alone. In a secondary set of univariate analyses, the associations between apical resorption and each of 14 additional treatment-related variables were examined. Only Gender, Elapsed Time, and Total Apical Displacement displayed statistically significant associations with apical resorption. Additional multiple regressions were then performed in which the data for each of these three statistically significant variables were considered separately, with the data for the four directional displacement variables. The addition of information on Elapsed Time or Total Apical Displacement did not explain a significant additional portion of the variability in apical resorption. On the other hand, the addition of information on Gender to the information on the four directional displacement variables yielded an R2 value of 0.35, which indicated that these variables taken together could account for approximately a third of the observed variability in apical resorption in this sample.

Transfer of supinator motor branches to the posterior interosseous nerve in C7-T1 brachial plexus palsy.

PubMed

Bertelli, Jayme Augusto; Ghizoni, Marcos Flavio

2010-07-01

In C7-T1 palsies of the brachial plexus, shoulder and elbow function are preserved, but finger motion is absent. Finger flexion has been reconstructed by tendon or nerve transfers. Finger extension has been restored ineffectively by attaching the extensor tendons to the distal aspect of the dorsal radius (termed tenodesis) or by tendon transfers. In these palsies, supinator muscle function is preserved, because innervation stems from the C-6 root. The feasibility of transferring supinator branches to the posterior interosseous nerve has been documented in a previous anatomical study. In this paper, the authors report the clinical results of supinator motor nerve transfer to the posterior interosseous nerve in 4 patients with a C7-T1 root lesion. Four adult patients with C7-T1 root lesions underwent surgery between 5 and 7 months postinjury. The patients had preserved motion of the shoulder, elbow, and wrist, but they had complete palsy of finger motion. They underwent finger flexion reconstruction via transfer of the brachialis muscle, and finger and thumb extension were restored by transferring the supinator motor branches to the posterior interosseous nerve. This nerve transfer was performed through an incision over the proximal third of the radius. Dissection was carried out between the extensor carpi radialis brevis and the extensor digitorum communis. The patients were followed up as per regular protocol and underwent a final evaluation 12 months after surgery. To document the extent of recovery, the authors assessed the degree of active metacarpophalangeal joint extension of the long fingers. The thumb span was evaluated by measuring the distance between the thumb pulp and the lateral aspect of the index finger. Surgery to transfer the supinator motor branches to the posterior interosseous nerve was straightforward. Twelve months after surgery, all patients were capable of opening their hand and could fully extend their metacarpophalangeal joints. The distance of thumb abduction improved from 0 to 5 cm from the lateral aspect of the index finger. Transferring supinator motor nerves directly to the posterior interosseous nerve is effective in at least partially restoring thumb and finger extension in patients with lower-type injuries of the brachial plexus.

Axonal morphological changes following impulse activity in mouse peripheral nerve in vivo: the return pathway for sodium ions

PubMed Central

Trigo, Diogo; Smith, Kenneth J

2015-01-01

Myelinated axons can conduct sustained trains of impulses at high frequency, but this involves substantial ion movements that must be reversed to restore homeostasis. Little attention has been paid to the potential osmotic consequences of the ion movements or to the pathway taken by sodium ions returning to their original endoneurial location, given that the axolemmal Na+–K+-ATPase extrudes these ions into the periaxonal space beneath the myelin rather than into the endoneurium. Serial confocal imaging of fluorescent axons conducting at sustained physiological frequencies in vivo has revealed surprising morphological changes that may illuminate these problems. Saphenous nerves and spinal roots of anaesthetized transgenic mice expressing axoplasmic yellow fluorescent protein were stimulated electrically or pharmacologically (veratridine). Within 2 h, the axon herniated on one or both sides of the nodal membrane, displacing the paranodal myelin and widening the nodal gap. The herniated axoplasm became directed back towards the internode, forming a ‘cap’ up to 30 μm long. Concurrently, the fluid in the expanded periaxonal space accumulated into droplets that appeared to travel to the paranode, where they escaped. No such alterations occurred in axons treated with sodium channel or Na+–K+-ATPase inhibitors. Remarkably, impulse conduction continued throughout, and all these changes reversed spontaneously over hours or days. The morphological changes were verified ultrastructurally, and occurred in virtually all myelinated axons. The findings appear to reveal an overlooked part of the physiological repertoire of nerve fibres, and here they are interpreted in terms of osmotic changes that may illuminate the pathway by which sodium ions return to the endoneurial space after they have entered the axon during impulse conduction. PMID:25524071

Analysis of axonal regeneration in the central and peripheral nervous systems of the NG2-deficient mouse

PubMed Central

Hossain-Ibrahim, Mohammed K; Rezajooi, Kia; Stallcup, William B; Lieberman, Alexander R; Anderson, Patrick N

2007-01-01

Background The chondroitin sulphate proteoglycan NG2 blocks neurite outgrowth in vitro and has been proposed as a major inhibitor of axonal regeneration in the CNS. Although a substantial body of evidence underpins this hypothesis, it is challenged by recent findings including strong expression of NG2 in regenerating peripheral nerve. Results We studied axonal regeneration in the PNS and CNS of genetically engineered mice that do not express NG2, and in sex and age matched wild-type controls. In the CNS, we used anterograde tracing with BDA to study corticospinal tract (CST) axons after spinal cord injury and transganglionic labelling with CT-HRP to trace ascending sensory dorsal column (DC) axons after DC lesions and a conditioning lesion of the sciatic nerve. Injury to these fibre tracts resulted in no difference between knockout and wild-type mice in the ability of CST axons or DC axons to enter or cross the lesion site. Similarly, after dorsal root injury (with conditioning lesion), most regenerating dorsal root axons failed to grow across the dorsal root entry zone in both transgenic and wild-type mice. Following sciatic nerve injuries, functional recovery was assessed by analysis of the toe-spreading reflex and cutaneous sensitivity to Von Frey hairs. Anatomical correlates of regeneration were assessed by: retrograde labelling of regenerating dorsal root ganglion (DRG) cells with DiAsp; immunostaining with PGP 9.5 to visualise sensory reinnervation of plantar hindpaws; electron microscopic analysis of regenerating axons in tibial and digital nerves; and by silver-cholinesterase histochemical study of motor end plate reinnervation. We also examined functional and anatomical correlates of regeneration after injury of the facial nerve by assessing the time taken for whisker movements and corneal reflexes to recover and by retrograde labelling of regenerated axons with Fluorogold and DiAsp. None of the anatomical or functional analyses revealed significant differences between wild-type and knockout mice. Conclusion These findings show that NG2 is unlikely to be a major inhibitor of axonal regeneration after injury to the CNS, and, further, that NG2 is unlikely to be necessary for regeneration or functional recovery following peripheral nerve injury. PMID:17900358

Extradural cold block for selective neurostimulation of the bladder: development of a new technique.

PubMed

Schumacher, S; Bross, S; Scheepe, J R; Seif, C; Jünemann, K P; Alken, P

1999-03-01

Cryotechnique for selective block of the urethral sphincter and simultaneous activation of the bladder was developed to achieve physiological micturition during sacral anterior root stimulation (SARS). In ten foxhounds SARS of S2 was carried out while extradurally both spinal nerves S2 were cooled down from positive 25C in a stepwise fashion until a sphincter block was observed. Subsequently, SARS of S2 was performed while the pudendal nerves were cooled down from + 15C. The effects of spinal and pudendal nerve cold block on the urethral sphincter and bladder during SARS and the recovery time were monitored by urodynamic investigation. A complete cold block of the urethral sphincter during spinal nerve cooling was achieved in all cases. During pudendal nerve cooling, the sphincter was completely blocked in two, and incompletely blocked in four dogs. Cold block temperature of the spinal nerves averaged +11.7C and of the pudendal nerves +6.2C. During SARS and spinal nerve cooling, an increase in intravesical pressure up to 13 cm. water was recognized, and recovery time was on average 6.6 minutes. Intravesical pressure remained unchanged during pudendal nerve cooling, with recovery time being less than 1 minute. The cold block was always reversible. Cryotechnique is an excellent method for selective and reversible block of the urethral sphincter during SARS to avoid detrusor-sphincter-dyssynergia. The application of cryotechnique in functional electrical stimulation leads to an improvement of quality of life in para- or tetraplegic patients because of selective nerve stimulation with optimization of micturition, standing, walking and grasping and does so without the necessity of surgical dorsal root rhizotomy.

Morphological pattern of intrinsic nerve plexus distributed on the rabbit heart and interatrial septum

PubMed Central

Saburkina, Inga; Gukauskiene, Ligita; Rysevaite, Kristina; Brack, Kieran E; Pauza, Audrys G; Pauziene, Neringa; Pauza, Dainius H

2014-01-01

Although the rabbit is routinely used as the animal model of choice to investigate cardiac electrophysiology, the neuroanatomy of the rabbit heart is not well documented. The aim of this study was to examine the topography of the intrinsic nerve plexus located on the rabbit heart surface and interatrial septum stained histochemically for acetylcholinesterase using pressure-distended whole hearts and whole-mount preparations from 33 Californian rabbits. Mediastinal cardiac nerves entered the venous part of the heart along the root of the right cranial vein (superior caval vein) and at the bifurcation of the pulmonary trunk. The accessing nerves of the venous part of the heart passed into the nerve plexus of heart hilum at the heart base. Nerves approaching the heart extended epicardially and innervated the atria, interatrial septum and ventricles by five nerve subplexuses, i.e. left and middle dorsal, dorsal right atrial, ventral right and left atrial subplexuses. Numerous nerves accessed the arterial part of the arterial part of the heart hilum between the aorta and pulmonary trunk, and distributed onto ventricles by the left and right coronary subplexuses. Clusters of intrinsic cardiac neurons were concentrated at the heart base at the roots of pulmonary veins with some positioned on the infundibulum. The mean number of intrinsic neurons in the rabbit heart is not significantly affected by aging: 2200 ± 262 (range 1517–2788; aged) vs. 2118 ± 108 (range 1513–2822; juvenile). In conclusion, despite anatomic differences in the distribution of intrinsic cardiac neurons and the presence of well-developed nerve plexus within the heart hilum, the topography of all seven subplexuses of the intrinsic nerve plexus in rabbit heart corresponds rather well to other mammalian species, including humans. PMID:24527844

Reflex regulation of airway sympathetic nerves in guinea-pigs

PubMed Central

Oh, Eun Joo; Mazzone, Stuart B; Canning, Brendan J; Weinreich, Daniel

2006-01-01

Sympathetic nerves innervate the airways of most species but their reflex regulation has been essentially unstudied. Here we demonstrate sympathetic nerve-mediated reflex relaxation of airway smooth muscle measured in situ in the guinea-pig trachea. Retrograde tracing, immunohistochemistry and electrophysiological analysis identified a population of substance P-containing capsaicin-sensitive spinal afferent neurones in the upper thoracic (T1–T4) dorsal root ganglia (DRG) that innervate the airways and lung. After bilateral vagotomy, atropine pretreatment and precontraction of the trachealis with histamine, nebulized capsaicin (10–60 μm) evoked a 63 ± 7% reversal of the histamine-induced contraction of the trachealis. Either the β-adrenoceptor antagonist propranolol (2 μm, administered directly to the trachea) or bilateral sympathetic nerve denervation of the trachea essentially abolished these reflexes (10 ± 9% and 6 ± 4% relaxations, respectively), suggesting that they were mediated primarily, if not exclusively, by sympathetic adrenergic nerve activation. Cutting the upper thoracic dorsal roots carrying the central processes of airway spinal afferents also markedly blocked the relaxations (9 ± 5% relaxation). Comparable inhibitory effects were observed following intravenous pretreatment with neurokinin receptor antagonists (3 ± 7% relaxations). These reflexes were not accompanied by consistent changes in heart rate or blood pressure. By contrast, stimulating the rostral cut ends of the cervical vagus nerves also evoked a sympathetic adrenergic nerve-mediated relaxation that were accompanied by marked alterations in blood pressure. The results indicate that the capsaicin-induced reflex-mediated relaxation of airway smooth muscle following vagotomy is mediated by sequential activation of tachykinin-containing spinal afferent and sympathetic efferent nerves innervating airways. This sympathetic nerve-mediated response may serve to oppose airway contraction induced by parasympathetic nerve activation in the airways. PMID:16581869

Minimally Invasive Treatment for a Sacral Tarlov Cyst Through Tubular Retractors.

PubMed

Del Castillo-Calcáneo, Juan D; Navarro-Ramírez, Rodrigo; Nakhla, Jonathan; Kim, Eliana; Härtl, Roger

2017-12-01

Tarlov cysts (TC) are focal dilations of arachnoid and dura mater of the spinal posterior nerve root sheath that appear as cystic lesions of the nerve roots typically in the lower spine, especially in the sacrum, which can cause radicular symptoms when they increase in size and compress the nerve roots. Different open procedures have been described to treat TCs, but no minimally invasive procedures have been described to effectively address this pathology. A 29-year-old woman presented with right lower extremity pain and weakness. A magnetic resonance imaging scan demonstrated a lumbosacral TC that protruded through the right L5-S1 foramina. Through a small laminotomy, cyst drainage followed by neck ligation using a Scanlan modified technique through tubular retractors was performed. The patient recovered full motor function within the first days postoperatively and showed no signs of relapse at 6-month follow-up. Minimally invasive spine surgery through tubular retractors can be safely performed for successful excision and ligation of TC using a Scanlan modified technique. Copyright © 2017 Elsevier Inc. All rights reserved.

Occipital neuralgia secondary to unilateral atlantoaxial osteoarthritis: Case report and review of the literature

PubMed Central

Guha, Daipayan; Mohanty, Chandan; Tator, Charles H.; Shamji, Mohammed F.

2015-01-01

Background: Atlantoaxial osteoarthritis (AAOA), either in isolation or in the context of generalized peripheral or spinal arthritis, presents most commonly with neck pain and limitation of cervical rotational range of motion. Occipital neuralgia (ON) is only rarely attributed to AAOA, as fewer than 30 cases are described in the literature. Case Description: A 64-year-old female presented with progressive incapacitating cervicalgia and occipital headaches, refractory to medications, and local anesthetic blocks. Computed tomography and magnetic resonance imaging studies documented advanced unilateral atlantoaxial arthrosis with osteophytic compression that dorsally displaced the associated C2 nerve root. Surgical decompression and atlantoaxial fusion achieved rapid and complete relief of neuralgia. Ultimately, postoperative spinal imaging revealed osseous union. Conclusions: Atlantoaxial arthrosis must be considered in the differential diagnosis of ON. Surgical treatment is effective for managing refractory cases. Intraoperative neuronavigation is also a useful adjunct to guide instrumentation and the intraoperative extent of bony decompression. PMID:26759731

Innervation of the rabbit cardiac ventricles.

PubMed

Pauziene, Neringa; Alaburda, Paulius; Rysevaite-Kyguoliene, Kristina; Pauza, Audrys G; Inokaitis, Hermanas; Masaityte, Aiste; Rudokaite, Gabriele; Saburkina, Inga; Plisiene, Jurgita; Pauza, Dainius H

2016-01-01

The rabbit is widely used in experimental cardiac physiology, but the neuroanatomy of the rabbit heart remains insufficiently examined. This study aimed to ascertain the architecture of the intrinsic nerve plexus in the walls and septum of rabbit cardiac ventricles. In 51 rabbit hearts, a combined approach involving: (i) histochemical acetylcholinesterase staining of intrinsic neural structures in total cardiac ventricles; (ii) immunofluorescent labelling of intrinsic nerves, nerve fibres (NFs) and neuronal somata (NS); and (iii) transmission electron microscopy of intrinsic ventricular nerves and NFs was used. Mediastinal nerves access the ventral and lateral surfaces of both ventricles at a restricted site between the root of the ascending aorta and the pulmonary trunk. The dorsal surface of both ventricles is supplied by several epicardial nerves extending from the left dorsal ganglionated nerve subplexus on the dorsal left atrium. Ventral accessing nerves are thicker and more numerous than dorsal nerves. Intrinsic ventricular NS are rare on the conus arteriosus and the root of the pulmonary trunk. The number of ventricular NS ranged from 11 to 220 per heart. Four chemical phenotypes of NS within ventricular ganglia were identified, i.e. ganglionic cells positive for choline acetyltransferase (ChAT), neuronal nitric oxide synthase (nNOS), and biphenotypic, i.e. positive for both ChAT/nNOS and for ChAT/tyrosine hydroxylase. Clusters of small intensely fluorescent cells are distributed within or close to ganglia on the root of the pulmonary trunk, but not on the conus arteriosus. The largest and most numerous intrinsic nerves proceed within the epicardium. Scarce nerves were found near myocardial blood vessels, but the myocardium contained only a scarce meshwork of NFs. In the endocardium, large numbers of thin nerves and NFs proceed along the bundle of His and both its branches up to the apex of the ventricles. The endocardial meshwork of fine NFs was approximately eight times denser than the myocardial meshwork. Adrenergic NFs predominate considerably in all layers of the ventricular walls and septum, whereas NFs of other neurochemical phenotypes were in the minority and their amount differed between the epicardium, myocardium and endocardium. The densities of NFs positive for nNOS and ChAT were similar in the epicardium and endocardium, but NFs positive for nNOS in the myocardium were eight times more abundant than NFs positive for ChAT. Potentially sensory NFs positive for both calcitonin gene-related peptide and substance P were sparse in the myocardial layer, but numerous in epicardial nerves and particularly abundant within the endocardium. Electron microscopic observations demonstrate that intrinsic ventricular nerves have a distinctive morphology, which may be attributed to remodelling of the peripheral nerves after their access into the ventricular wall. In conclusion, the rabbit ventricles display complex structural organization of intrinsic ventricular nerves, NFs and ganglionic cells. The results provide a basic anatomical background for further functional analysis of the intrinsic nervous system in the cardiac ventricles. © 2015 Anatomical Society.

High-Resolution Isotropic Three-Dimensional MR Imaging of the Extraforaminal Segments of the Cranial Nerves.

PubMed

Wen, Jessica; Desai, Naman S; Jeffery, Dean; Aygun, Nafi; Blitz, Ari

2018-02-01

High-resolution isotropic 3-dimensional (D) MR imaging with and without contrast is now routinely used for imaging evaluation of cranial nerve anatomy and pathologic conditions. The anatomic details of the extraforaminal segments are well-visualized on these techniques. A wide range of pathologic entities may cause enhancement or displacement of the nerve, which is now visible to an extent not available on standard 2D imaging. This article highlights the anatomy of extraforaminal segments of the cranial nerves and uses select cases to illustrate the utility and power of these sequences, with a focus on constructive interference in steady-state. Copyright © 2017 Elsevier Inc. All rights reserved.

Influence of myelinated retinal nerve fibers on retinal vessel density measurement with AngioVue OCT angiography.

PubMed

Holló, Gábor

2016-12-01

Myelinated retinal nerve fibers (MRNF) represent an asymptomatic developmental anomaly in which myelin sheaths extend to a group of retinal nerve fibers along their intraocular portion. The additional volume of the myelin sheaths causes displacement of the axons toward the vitreous body. We investigated the effect of localized MRNF on peripapillary vessel density measurement results using optical coherence tomography (OCT) angiography. Peripapillary angioflow density measurements (PAFD, % of the analyzed retinal area) were made with the AngioVue OCT (Optovue Inc., Fremont, USA). In both cases, the predominant position of MRNF was inferonasal to the disk. Vessel density was clearly greater in the area of the MRNF than in the surrounding retina in the optic nerve head (ONH) level, but it was lower than in the surrounding retina in the retinal nerve fiber layer (RNFL) level. In the ONH level, PAFD was higher in the MRNF area than in the spatially corresponding superonasal area (Case 1: 64.6 vs. 57.6 %; Case 2: 65.8 vs. 56.3 %). In contrast, in the RNFL level, PAFD was lower in the MRNF area than in the corresponding superonasal area (Case 1: 60.1 vs. 65.4 %; Case 2: 46.5 vs. 58.5 %). Our cases show that the effect of MRNF on OCT angiography vessel density is different in the different measurement layers. Clinicians may separate decreased vessel density caused by anterior RNFL displacement in MRNF areas from that caused by nerve fiber damage in optic neuropathies by evaluating PAFD in both the ONH and RNFL levels.

Hemifacial Spasm and Neurovascular Compression

PubMed Central

Lu, Alex Y.; Yeung, Jacky T.; Gerrard, Jason L.; Michaelides, Elias M.; Sekula, Raymond F.; Bulsara, Ketan R.

2014-01-01

Hemifacial spasm (HFS) is characterized by involuntary unilateral contractions of the muscles innervated by the ipsilateral facial nerve, usually starting around the eyes before progressing inferiorly to the cheek, mouth, and neck. Its prevalence is 9.8 per 100,000 persons with an average age of onset of 44 years. The accepted pathophysiology of HFS suggests that it is a disease process of the nerve root entry zone of the facial nerve. HFS can be divided into two types: primary and secondary. Primary HFS is triggered by vascular compression whereas secondary HFS comprises all other causes of facial nerve damage. Clinical examination and imaging modalities such as electromyography (EMG) and magnetic resonance imaging (MRI) are useful to differentiate HFS from other facial movement disorders and for intraoperative planning. The standard medical management for HFS is botulinum neurotoxin (BoNT) injections, which provides low-risk but limited symptomatic relief. The only curative treatment for HFS is microvascular decompression (MVD), a surgical intervention that provides lasting symptomatic relief by reducing compression of the facial nerve root. With a low rate of complications such as hearing loss, MVD remains the treatment of choice for HFS patients as intraoperative technique and monitoring continue to improve. PMID:25405219

Clinical Evaluation of Targeting Accuracy of Gamma Knife Radiosurgery in Trigeminal Neuralgia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Massager, Nicolas; Abeloos, Laurence; Devriendt, Daniel

2007-12-01

Purpose: The efficiency of radiosurgery is related to its highly precise targeting. We assessed clinically the targeting accuracy of radiosurgical treatment with the Leksell Gamma Knife for trigeminal neuralgia. We also studied the applied radiation dose within the area of focal contrast enhancement on the trigeminal nerve root following radiosurgery. Methods and Materials: From an initial group of 78 patients with trigeminal neuralgia treated with gamma knife radiosurgery using a 90-Gy dose, we analyzed a subgroup of 65 patients for whom 6-month follow-up MRI showed focal contrast enhancement of the trigeminal nerve. Follow-up MRI was spatially coregistered to the radiosurgicalmore » planning MRI. Target accuracy was assessed from deviation of the coordinates of the intended target compared with the center of enhancement on postoperative MRI. Radiation dose delivered at the borders of contrast enhancement was evaluated. Results: The median deviation of the coordinates between the intended target and the center of contrast enhancement was 0.91 mm in Euclidean space. The radiation doses fitting within the borders of the contrast enhancement of the trigeminal nerve root ranged from 49 to 85 Gy (median value, 77 {+-} 8.7 Gy). Conclusions: The median deviation found in clinical assessment of gamma knife treatment for trigeminal neuralgia is low and compatible with its high rate of efficiency. Focal enhancement of the trigeminal nerve after radiosurgery occurred in 83% of our patients and was not associated with clinical outcome. Focal enhancement borders along the nerve root fit with a median dose of 77 {+-} 8.7 Gy.« less

Acute myelopathy selectively involving lumbar anterior horns following intranasal insufflation of ecstasy and heroin

PubMed Central

Riva, Nilo; Riva, Nilo; Morana, Paolo; Cerri, Federica; Gerevini, Simonetta; Amadio, Stefano; Formaglio, Fabio; Comi, Giancarlo; Comola, Mauro; Del Carro, Ubaldo

2009-01-01

We report a patient who developed acute myelopathy after intranasal insufflation of amphetamines and heroin. The functional prognosis was very poor; after 4 months, she remained paraplegic. MRI imaging showed selective T2 hyperintensity and intense enhancement confined to the spinal anterior horns and lumbar nerve roots and plexus. This unique MRI pattern, together with neurophysiological data, suggests that the pathological process at the first primary affected spinal anterior horns (SAH), conditioning motoneuron cell death, and then nerve roots and lumbar plexus as a consequence of wallerian degeneration PMID:21686691

The initiation of lateral roots in the primary roots of maize (Zea mays L.) implies a reactivation of cell proliferation in a group of founder pericycle cells.

PubMed

Alarcón, M Victoria; Lloret, Pedro G; Martín-Partido, Gervasio; Salguero, Julio

2016-03-15

The initiation of lateral roots (LRs) has generally been viewed as a reactivation of proliferative activity in pericycle cells that are committed to initiate primordia. However, it is also possible that pericycle founder cells that initiate LRs never cease proliferative activity but rather are displaced to the most distal root zones while undertaking successive stages of LR initiation. In this study, we tested these two alternative hypotheses by examining the incorporation of 5-bromo-2'-deoxyuridine (BrdU) into the DNA of meristematic root cells of Zea mays. According to the values for the length of the cell cycle and values for cell displacement along the maize root, our results strongly suggest that pericycle cells that initiate LR primordia ceased proliferative activity upon exiting the meristematic zone. This finding is supported by the existence of a root zone between 4 and 20mm from the root cap junction, in which neither mitotic cells nor labelled nuclei were observed in phloem pericycle cells. Copyright © 2016 Elsevier GmbH. All rights reserved.

Aberrant gastrocnemius muscle innervation by tibial nerve afferents after implantation of chitosan tubes impregnated with progesterone favored locomotion recovery in rats with transected sciatic nerve.

PubMed

Sarabia-Estrada, Rachel; Bañuelos-Pineda, Jacinto; Osuna Carrasco, Laura P; Jiménez-Vallejo, Salvador; Jiménez-Estrada, Ismael; Rivas-Celis, Efrain; Dueñas-Jiménez, Judith M; Dueñas-Jiménez, Sergio H

2015-07-01

Transection of peripheral nerves produces loss of sensory and/or motor function. After complete nerve cutting, the distal and proximal segment ends retract, but if both ends are bridged with unaltered chitosan, progesterone-impregnated chitosan, or silicone tubes, an axonal repair process begins. Progesterone promotes nerve repair and has neuroprotective effects thwarting regulation of neuron survival, inflammation, and edema. It also modulates aberrant axonal sprouting and demyelination. The authors compared the efficacy of nerve recovery after implantation of progesterone-loaded chitosan, unaltered chitosan, or silicone tubes after sciatic nerve transection in rats. After surgical removal of a 5-mm segment of the proximal sciatic nerve, rats were implanted with progesterone-loaded chitosan, unaltered chitosan, or silicone tubes in the transected nerve for evaluating progesterone and chitosan effects on sciatic nerve repair and ipsilateral hindlimb kinematic function, as well as on gastrocnemius electro-myographic responses. In some experiments, tube implantation was performed 90 minutes after nerve transection. At 90 days after sciatic nerve transection and tube implantation, rats with progesterone-loaded chitosan tubes showed knee angular displacement recovery and better outcomes for step length, velocity of locomotion, and normal hindlimb raising above the ground. In contrast, rats with chitosan-only tubes showed reduced normal raising and pendulum-like hindlimb movements. Aberrant fibers coming from the tibial nerve innervated the gastrocnemius muscle, producing electromyographic responses. Electrical responses in the gastrocnemius muscle produced by sciatic nerve stimulation occurred only when the distal nerve segment was stimulated; they were absent when the proximal or intratubular segment was stimulated. A clear sciatic nerve morphology with some myelinated fiber fascicles appeared in the tube section in rats with progesterone-impregnated chitosan tubes. Some gastrocnemius efferent fibers were partially repaired 90 days after nerve resection. The better outcome in knee angle displacement may be partially attributable to the aberrant neuromuscular synaptic effects, since nerve conduction in the gastrocnemius muscle could be blocked in the progesterone-impregnated chitosan tubes. In addition, in the region of the gap produced by the nerve resection, the number of axons and amount of myelination were reduced in the sciatic nerve implanted with chitosan, progesterone-loaded chitosan, and silicone tubes. At 180 days after sciatic nerve sectioning, the knee kinematic function recovered to a level observed in control rats of a similar age. In rats with progesterone-loaded chitosan tubes, stimulation of the proximal and intratubular sciatic nerve segments produced an electromyographic response. The axon morphology of the proximal and intratubular segments of the sciatic nerve resembled that of the contralateral nontransected nerve. Progesterone-impregnated chitosan tubes produced aberrant innervation of the gastrocnemius muscle, which allowed partial recovery of gait locomotion and could be adequate for reinnervating synergistic denervated muscles while a parent innervation is reestablished. Hindlimb kinematic parameters differed between younger (those at 90 days) and older (those at 180 days) rats.

Cupula displacement, hair bundle deflection, and physiological responses in the transparent semicircular canal of young eel.

PubMed

Rüsch, A; Thurm, U

1989-03-01

The transparent labyrinth of young eels (Anguilla anguilla L.) was used in toto for studying the configuration of cupula displacement, deflection of the hair bundle, and correlated changes in transepithelial voltage (delta TEV) and nerve activity (delta NA) in the semicircular canal. Microcapillaries were introduced into the canal through holes produced by a microthermocauter. Mechanical stimulation was applied either by injection of fluid into the ampulla or by electromagnetically displacing ferrofluid as a piston within the canal. Motion of individual kinocilia, stained cupulae or the ferrofluid piston was analysed by double-exposed microphotographs, photodiodes, or a video-system. The three-dimensional cupula displacement configuration was found to be piston- to diaphragm-like. Hair bundles at different sites on the crista exhibit differences in amplitude and time course of deflection. The transfer factor between shifts of the canal fluid and the tips of the kinocilia is 0.4-0.6. Displacements in opposite directions induce delta TEV and delta NA of opposite sign. Various tests confirmed delta TEV to reflect receptor potential responses. Nerve activity adapts to a tonic response with a time constant of 6.4 s. No similar adaptation occurred in delta TEV. Stimulus-response curves of TEV- and NA-responses are similar and sigmoid in shape with saturation at ciliary deflections of roughly +6 degrees and -3 degrees.

Use of NK1 receptor antagonists in the exploration of physiological functions of substance P and neurokinin A.

PubMed

Otsuka, M; Yoshioka, K; Yanagisawa, M; Suzuki, H; Zhao, F Y; Guo, J Z; Hosoki, R; Kurihara, T

1995-07-01

Tachykinin NK1 receptor antagonists were used to explore the physiological functions of substance P (SP) and neurokinin A (NKA). Pharmacological profiles of three NK1 receptor antagonists, GR71251, GR82334, and RP 67580, were examined in the isolated spinal cord preparation of the neonatal rat. These tachykinin receptor antagonists exhibited considerable specificities and antagonized the actions of both SP and NKA to induce the depolarization of ventral roots. Electrical stimulation of the saphenous nerve with C-fiber strength evoked a depolarization lasting about 30 s of the ipsilateral L3 ventral root. This response, which is referred to as saphenous-nerve-evoked slow ventral root potential (VRP), was depressed by these NK1 receptor antagonists. In contrast, the saphenous-nerve-evoked slow VRP was potentiated by application of a mixture of peptidase inhibitors, including thiorphan, actinonin, and captopril in the presence of naloxone, but not after further addition of GR71251. Likewise, in the isolated coeliac ganglion of the guinea pig, electrical stimulation of the mesenteric nerves evoked in some ganglionic cells slow excitatory postsynaptic potentials (EPSPs), which were depressed by GR71251 and potentiated by peptidase inhibitors. These results further support the notion that SP and NKA serve as neurotransmitters producing slow EPSPs in the neonatal rat spinal cord and guinea pig prevertebral ganglia.

Comparative study of phrenic nerve transfers with and without nerve graft for elbow flexion after global brachial plexus injury.

PubMed

Liu, Yuzhou; Lao, Jie; Gao, Kaiming; Gu, Yudong; Zhao, Xin

2014-01-01

Nerve transfer is a valuable surgical technique in peripheral nerve reconstruction, especially in brachial plexus injuries. Phrenic nerve transfer for elbow flexion was proved to be one of the optimal procedures in the treatment of brachial plexus injuries in the study of Gu et al. The aim of this study was to compare phrenic nerve transfers with and without nerve graft for elbow flexion after brachial plexus injury. A retrospective review of 33 patients treated with phrenic nerve transfer for elbow flexion in posttraumatic global root avulsion brachial plexus injury was carried out. All the 33 patients were confirmed to have global root avulsion brachial plexus injury by preoperative and intraoperative electromyography (EMG), physical examination and especially by intraoperative exploration. There were two types of phrenic nerve transfers: type1 - the phrenic nerve to anterolateral bundle of anterior division of upper trunk (14 patients); type 2 - the phrenic nerve via nerve graft to anterolateral bundle of musculocutaneous nerve (19 patients). Motor function and EMG evaluation were performed at least 3 years after surgery. The efficiency of motor function in type 1 was 86%, while it was 84% in type 2. The two groups were not statistically different in terms of Medical Research Council (MRC) grade (p=1.000) and EMG results (p=1.000). There were seven patients with more than 4 month's delay of surgery, among whom only three patients regained biceps power to M3 strength or above (43%). A total of 26 patients had reconstruction done within 4 months, among whom 25 patients recovered to M3 strength or above (96%). There was a statistically significant difference of motor function between the delay of surgery within 4 months and more than 4 months (p=0.008). Phrenic nerve transfers with and without nerve graft for elbow flexion after brachial plexus injury had no significant difference for biceps reinnervation according to MRC grading and EMG. A delay of the surgery after the 4 months might imply a bad prognosis for the recovery of the function. Copyright © 2012 Elsevier Ltd. All rights reserved.

Use of piezosurgery device in management of oral surgery complications: clincal case and clinical experience report.

PubMed

Sammartino, G; Riccitiello, F; Trosino, O; Marenzi, G; Cioffi, A; Mortellaro, C

2012-05-01

The root displacement into the maxillary sinus could be a complication of oral surgery in the upper jaw. In these cases, the root removal is needed in order to avoid the occurrence of sinus pathologies. Piezosurgery techniques could assure a safer management of such complications, because of the clear surgical visibility and the selective ability of cut. The aim of this article is to present a case of oral surgery complication (root displacement in the right maxillary sinus), in which piezosurgery technique helped for a correct and safe clinical management, allowing to reduce the soft tissue damage.

Upregulation of Ryk expression in rat dorsal root ganglia after peripheral nerve injury.

PubMed

Li, Xin; Li, Yao-hua; Yu, Shun; Liu, Yaobo

2008-10-22

To study changes of Ryk expression in dorsal root ganglia (DRG) after peripheral nerve injury, we set up an animal model of unilateral sciatic nerve lesioned rats. Changes of Ryk protein expression in DRG neurons after unilateral sciatic nerve injury were investigated by immunostaining. Changes of Ryk mRNA were also tested by semi-quantitative PCR concurrently. We found, both at the level of protein and mRNA, that Ryk could be induced in cells of ipsilateral DRG after unilateral sciatic nerve lesion. Further investigation by co-immunostaining confirmed that the Ryk-immunoreactive (Ryk-IR) cells were NeuN-immunoreactive (NeuN-IR) neurons of DRG. We also showed the pattern of Ryk induction in DRG neurons after sciatic nerve injury: the number of Ryk IR neurons peaked at 2 weeks post-lesion and decreased gradually by 3 weeks post-lesion. The proportions of different sized Ryk IR neurons were also observed and counted at various stages after nerve lesion. Analysis of Ryk mRNA by RT-PCR showed the same induction pattern as by immunostaining. Ryk mRNA was not expressed in normal or contralateral DRG, but was expressed 1, 2 and 3 weeks post-lesion in the ipsilateral DRG. Ryk mRNA levels increased slightly from 1 to 2 weeks, decreased then by 3 weeks post-lesion. These results indicate that Ryk might be involved in peripheral nerve plasticity after injury. This is a novel function apart from its well-known fundamental activity as a receptor mediating axon guidance and outgrowth.

Identification and Characterization of Novel Catalytic Bioscavengers of Organophosphorus Nerve Agents

DTIC Science & Technology

2013-01-01

hydrolase activity . These strains are Ammoniphilus oxalaticus, Haloarcula sp., and Micromonospora aurantiaca. Lysates from A. oxalaticus had...warfare agents [1–3]. OP nerve agents readily bind covalently to the active site serine in acetylcho- linesterase (AChE), thereby inhibiting the ability...muscarinic receptors, whereas 2-pralidoxime chloride, an oxime nucleophile, reactivates AChE by displacing the phospho- nyl group left on the active site

Influence of low back pain and prognostic value of MRI in sciatica patients in relation to back pain.

PubMed

el Barzouhi, Abdelilah; Vleggeert-Lankamp, Carmen L A M; Lycklama à Nijeholt, Geert J; Van der Kallen, Bas F; van den Hout, Wilbert B; Koes, Bart W; Peul, Wilco C

2014-01-01

Patients with sciatica frequently complain about associated back pain. It is not known whether there are prognostic relevant differences in Magnetic Resonance Imaging (MRI) findings between sciatica patients with and without disabling back pain. The study population contained patients with sciatica who underwent a baseline MRI to assess eligibility for a randomized trial designed to compare the efficacy of early surgery with prolonged conservative care for sciatica. Two neuroradiologists and one neurosurgeon independently evaluated all MR images. The MRI readers were blinded to symptom status. The MRI findings were compared between sciatica patients with and without disabling back pain. The presence of disabling back pain at baseline was correlated with perceived recovery at one year. Of 379 included sciatica patients, 158 (42%) had disabling back pain. Of the patients with both sciatica and disabling back pain 68% did reveal a herniated disc with nerve root compression on MRI, compared to 88% of patients with predominantly sciatica (P<0.001). The existence of disabling back pain in sciatica at baseline was negatively associated with perceived recovery at one year (Odds ratio [OR] 0.32, 95% Confidence Interval 0.18-0.56, P<0.001). Sciatica patients with disabling back pain in absence of nerve root compression on MRI at baseline reported less perceived recovery at one year compared to those with predominantly sciatica and nerve root compression on MRI (50% vs 91%, P<0.001). Sciatica patients with disabling low back pain reported an unfavorable outcome at one-year follow-up compared to those with predominantly sciatica. If additionally a clear herniated disc with nerve root compression on MRI was absent, the results were even worse.

Influence of Low Back Pain and Prognostic Value of MRI in Sciatica Patients in Relation to Back Pain

PubMed Central

el Barzouhi, Abdelilah; Vleggeert-Lankamp, Carmen L. A. M.; Lycklama à Nijeholt, Geert J.; Van der Kallen, Bas F.; van den Hout, Wilbert B.; Koes, Bart W.; Peul, Wilco C.

2014-01-01

Background Patients with sciatica frequently complain about associated back pain. It is not known whether there are prognostic relevant differences in Magnetic Resonance Imaging (MRI) findings between sciatica patients with and without disabling back pain. Methods The study population contained patients with sciatica who underwent a baseline MRI to assess eligibility for a randomized trial designed to compare the efficacy of early surgery with prolonged conservative care for sciatica. Two neuroradiologists and one neurosurgeon independently evaluated all MR images. The MRI readers were blinded to symptom status. The MRI findings were compared between sciatica patients with and without disabling back pain. The presence of disabling back pain at baseline was correlated with perceived recovery at one year. Results Of 379 included sciatica patients, 158 (42%) had disabling back pain. Of the patients with both sciatica and disabling back pain 68% did reveal a herniated disc with nerve root compression on MRI, compared to 88% of patients with predominantly sciatica (P<0.001). The existence of disabling back pain in sciatica at baseline was negatively associated with perceived recovery at one year (Odds ratio [OR] 0.32, 95% Confidence Interval 0.18–0.56, P<0.001). Sciatica patients with disabling back pain in absence of nerve root compression on MRI at baseline reported less perceived recovery at one year compared to those with predominantly sciatica and nerve root compression on MRI (50% vs 91%, P<0.001). Conclusion Sciatica patients with disabling low back pain reported an unfavorable outcome at one-year follow-up compared to those with predominantly sciatica. If additionally a clear herniated disc with nerve root compression on MRI was absent, the results were even worse. PMID:24637890

Atlantoaxial Fusion Using C1 Sublaminar Cables and C2 Translaminar Screws.

PubMed

Larsen, Alexandra M Giantini; Grannan, Benjamin L; Koffie, Robert M; Coumans, Jean-Valéry

2018-06-01

Atlantoaxial instability, which can arise in the setting of trauma, degenerative diseases, and neoplasm, is often managed surgically with C1-C2 arthrodesis. Classical C1-C2 fusion techniques require placement of instrumentation in close proximity to the vertebral artery and C2 nerve root. To report a novel C1-C2 fusion technique that utilizes C2 translaminar screws and C1 sublaminar cables to decrease the risk of injury to the vertebral artery and C2 nerve root. To facilitate fixation to the atlas, while minimizing the risk of injury to the vertebral artery and to the C2 nerve root, we sought to determine the feasibility of using a soft cable around the C1 arch and affixing it to a rod connected to C2 laminar screws. We reviewed our experience in 3 patients. We used this technique in patients in whom we anticipated difficult C1 screw placement. Three patients were identified through a review of the senior author's cases. Atlantoaxial instability was associated with trauma in 2 patients and chronic degenerative changes in 1 patient. Common symptoms on presentation included pain and limited range of motion. All patients underwent C1-C2 fusion with C2 translaminar screws with sublaminar cable harnessing of the posterior arch of C1. There were no reports of postoperative complications or hardware failure. We demonstrate a novel, technically straightforward approach for C1-C2 fusion that minimizes risk to the vertebral artery and to the C2 nerve root, while still allowing for semirigid fixation in instances of both traumatic and chronic degenerative atlantoaxial instability.

[Usefulness of curved coronal MPR imaging for the diagnosis of cervical radiculopathy].

PubMed

Inukai, Chikage; Inukai, Takashi; Matsuo, Naoki; Shimizu, Ikuo; Goto, Hisaharu; Takagi, Teruhide; Takayasu, Masakazu

2010-03-01

In surgical treatment of cervical radiculopathy, localization of the responsible lesions by various imaging modalities is essential. Among them, MRI is non-invasive and plays a primary role in the assessment of spinal radicular symptoms. However, demonstration of nerve root compression is sometimes difficult by the conventional methods of MRI, such as T1 weighted (T1W) and T2 weighted (T2W) sagittal or axial images. We have applied a new technique of curved coronal multiplanar reconstruction (MPR) imaging for the diagnosis of cervical radiculopathy. Ten patients (4 male, 6 female) with ages between 31 and 79 year-old, who had clinical diagnosis of cervical radiculopathy, were included in this study. Seven patients underwent anterior key-hole foraminotomy to decompress the nerve root with successful results. All the patients had 3D MRI studies, such as true fast imaging with steady-state precession (FISP), 3DT2W sampling perfection with application optimized contrasts using different fillip angle evolution (SPACE), and 3D multi-echo data image combination (MEDIC) imagings in addition to the routine MRI (1.5 T Avanto, Siemens, Germany) with a phased array coil. The curved coronal MPR images were produced from these MRI data using a workstation. The nerve root compression was diagnosed by curved coronal MPR images in all the patients. The compression sites were compatible with those of the operative findings in 7 patients, who underwent surgical treatment. The MEDIC imagings were the most demonstrable to visualize the nerve root, while the 3D-space imagings were the next. The curved coronal MPR imaging is useful for the diagnosis of accurate localization of the compressing lesions in patients with cervical radiculopathy.

A posterior approach to cervical nerve root block and pulsed radiofrequency treatment for cervical radicular pain: a retrospective study.

PubMed

Xiao, Lizu; Li, Jie; Li, Disen; Yan, Dong; Yang, Jun; Wang, Daniel; Cheng, Jianguo

2015-09-01

Catastrophic complications have been reported for selective cervical nerve root block (SCNRB) or pulsed radiofrequency (PRF) via an anterolateral transforaminal approach. A posterior approach to these procedures under computed tomography guidance has been reported. Here, we report the clinical outcomes of 42 patients with chronic cervical radicular pain (CCRP) treated with a combination of SCNRB and PRF through a posterior approach under fluoroscopy guidance. We retrospectively reviewed the clinical outcomes of 42 consecutive patients with CCRP who received a combination of SCNRB and PRF through a posterior approach under fluoroscopy guidance. The thresholds of electrical stimulation and imaging of the nerve roots after contrast injection were used to evaluate the accuracy of needle placement. The numeric rating scale was used to measure the pain and numbness levels as primary clinical outcomes, which were evaluate in scheduled follow-up visits of up to 3 months. A total of 53 procedures were performed on 42 patients at the levels of C5-C8. All patients reported concordant paresthesia in response to electrical stimulation. The average sensory and motor thresholds of stimulation were 0.28 ± 0.14 and 0.36 ± 0.14 V, respectively. Injection of nonionic contrast resulted in excellent spread along the target nerve root in large majority of the procedures. The numeric rating scale scores for both pain and numbness improved significantly at 1 day, 1 week, and 1 and 3 months after the treatment. No serious adverse effects were observed in any of the patients. The posterior approach to combined SCNRB and PRF under fluoroscopy guidance appears to be safe and efficacious in the management of CCRP. Copyright © 2015 Elsevier Inc. All rights reserved.

Influence of needle position on lumbar segmental nerve root block selectivity.

PubMed

Wolff, André P; Groen, Gerbrand J; Wilder-Smith, Oliver H

2006-01-01

In patients with chronic low back pain radiating to the leg, segmental nerve root blocks (SNRBs) are performed to predict surgical outcome and identify the putative symptomatic spinal nerve. Epidural spread may lead to false interpretation, affecting clinical decision making. Systematic fluoroscopic analysis of epidural local anesthetic spread and its relationship to needle tip location has not been published to date. Study aims include assessment of epidural local anesthetic spread and its relationship to needle position during fluoroscopy-assisted blocks. Patients scheduled for L4, L5, and S1 blocks were included in this prospective observational study. Under fluoroscopy and electrostimulation, they received 0.5 mL of a mixture containing lidocaine 5 mg and iohexol 75 mg. X-rays with needle tip and contrast were scored for no epidural spread (grade 0), local spread epidurally (grade 1), or to adjacent nerve roots (grade 2). Sixty-five patients were analyzed for epidural spread, 62 for needle position. Grade 1 epidural spread occurred in 47% of L4 and 28% of L5 blocks and grade 2 spread in 3 blocks (5%; L5 n = 1, S1 n = 2). For lumbar blocks, the needle was most frequently found in the lateral upper half of the intervertebral foramen. Epidural spread occurred more frequently with medial needle positions (P = .06). The findings suggest (P = .06) that the risk of grade 1 and 2 lumbar epidural spread, which results in decreased SNRB selectivity, is greater with medial needle positions in the intervertebral foramen. The variability in anatomic position of the dorsal root ganglion necessitates electrostimulation to guide SNRB in addition to fluoroscopy.

Root negative gravitropism is accompanied with displacing of columella amyloplasts to the statocyte upper longitudinal cell wall

NASA Astrophysics Data System (ADS)

Kordyum, Elizabeth; Sobol, Margaryta; Kalinina, Yana; Bogatina, Nina; Kondrachuk, Alexander

Recently it was shown that roots reveal negative gravitropism in the weak combined magnetic field (CMF) with the frequency resonance to the cyclotron frequency of Ca2+ ions. A negative gravitropic reaction in the CMF occurs by a usual physiological process. Experiments in the CMF confirmed that gravitropism is plastid-based and Ca2+ ions participate in this process. Unlike control, amyloplasts-statoliths are not displacing on the lower side of a gravistimulated root but tend to group in the center of a statocyte during 30 min under gravistimulation in the CMF. In an hour of gravistimulation, they are localized near one of the statocyte longitudinal wall. Now we determined that amyloplasts are localized along the statocyte upper longitudinal side. It is of a special interest that a root is bending to the same direction with displacing of amyloplasts: in positive gravitropism - downwards, in negative gravitropism - upwards. On the basis of the obtained data there is a question, what forces promote displacing of amyloplasts against a gravitational vector? In the paper, three possible explanations are discussed: 1) CMF + Ca2+ action on the distribution of elastic forces in cytoskeleton, 2) CMF + Ca2+ action on the distribution of electric field in statocytes, and 3) CMF action on energy and direction of Ca2+ ion rotation according to the ion cyclotron resonance model that can lead to paradoxical Ca2+ redistribution.

Assessing the changes in the spatial stiffness of the posterior sclera as a function of IOP with air-pulse OCE

NASA Astrophysics Data System (ADS)

Singh, Manmohan; Nair, Achuth; Aglyamov, Salavat R.; Wu, Chen; Han, Zhaolong; Lafon, Ericka; Larin, Kirill V.

2017-02-01

The mechanophysiology of tissues in the posterior eye have been implicated for diseases such as myopia and glaucoma. For example, the eye-globe shape, and consequently optical axial length, can be affected by scleral stiffness. In glaucoma, an elevated intraocular pressure is the primary risk factor for glaucoma, which is the 2nd most prevalent known cause of blindness. Recent work has shown that biomechanical properties of the optic nerve are critical for the onset and progression of glaucoma because weak tissues cause large displacements in the optic nerve, causing tissue damage. In this work, we utilize air-pulse optical coherence elastography (OCE) to quantify the spatial distribution of biomechanical properties of the optic nerve, its surrounding tissues, and the posterior sclera. Air-pulse measurements were made in a grid on in situ porcine eyes in the whole eye-globe configuration as various IOPs. The OCE-measured displacement process was linked to tissue stiffness by a simple kinematic equation. The results show that the optic nerve and peripapillary sclera are much stiffer than the surrounding sclera, and the stiffness of the optic nerve and peripapillary sclera increased as a function of IOP. However, the stiffness of the surrounding sclera did not dramatically increase. Our results show that understanding the dynamics of the biomechanical properties of the eye are critical to understand the aforementioned diseases and may provide additional information for assessing visual health and integrity.

Derivation of formulas for root-mean-square errors in location, orientation, and shape in triangulation solution of an elongated object in space

NASA Technical Reports Server (NTRS)

Long, S. A. T.

1974-01-01

Formulas are derived for the root-mean-square (rms) displacement, slope, and curvature errors in an azimuth-elevation image trace of an elongated object in space, as functions of the number and spacing of the input data points and the rms elevation error in the individual input data points from a single observation station. Also, formulas are derived for the total rms displacement, slope, and curvature error vectors in the triangulation solution of an elongated object in space due to the rms displacement, slope, and curvature errors, respectively, in the azimuth-elevation image traces from different observation stations. The total rms displacement, slope, and curvature error vectors provide useful measure numbers for determining the relative merits of two or more different triangulation procedures applicable to elongated objects in space.

Three-dimensional kinematic stress magnetic resonance image analysis shows promise for detecting altered anatomical relationships of tissues in the cervical spine associated with painful radiculopathy.

PubMed

Jaumard, N V; Udupa, J K; Siegler, S; Schuster, J M; Hilibrand, A S; Hirsch, B E; Borthakur, A; Winkelstein, B A

2013-10-01

For some patients with radiculopathy a source of nerve root compression cannot be identified despite positive electromyography (EMG) evidence. This discrepancy hampers the effective clinical management for these individuals. Although it has been well-established that tissues in the cervical spine move in a three-dimensional (3D) manner, the 3D motions of the neural elements and their relationship to the bones surrounding them are largely unknown even for asymptomatic normal subjects. We hypothesize that abnormal mechanical loading of cervical nerve roots during pain-provoking head positioning may be responsible for radicular pain in those cases in which there is no evidence of nerve root compression on conventional cervical magnetic resonance imaging (MRI) with the neck in the neutral position. This biomechanical imaging proof-of-concept study focused on quantitatively defining the architectural relationships between the neural and bony structures in the cervical spine using measurements derived from 3D MR images acquired in neutral and pain-provoking neck positions for subjects: (1) with radicular symptoms and evidence of root compression by conventional MRI and positive EMG, (2) with radicular symptoms and no evidence of root compression by MRI but positive EMG, and (3) asymptomatic age-matched controls. Function and pain scores were measured, along with neck range of motion, for all subjects. MR imaging was performed in both a neutral position and a pain-provoking position. Anatomical architectural data derived from analysis of the 3D MR images were compared between symptomatic and asymptomatic groups, and the symptomatic groups with and without imaging evidence of root compression. Several differences in the architectural relationships between the bone and neural tissues were identified between the asymptomatic and symptomatic groups. In addition, changes in architectural relationships were also detected between the symptomatic groups with and without imaging evidence of nerve root compression. As demonstrated in the data and a case study the 3D stress MR imaging approach provides utility to identify biomechanical relationships between hard and soft tissues that are otherwise undetected by standard clinical imaging methods. This technique offers a promising approach to detect the source of radiculopathy to inform clinical management for this pathology. Copyright © 2013 Elsevier Ltd. All rights reserved.

Influence of oculomotor nerve afferents on central endings of primary trigeminal fibers.

PubMed

Manni, E; Bortolami, R; Pettorossi, V E; Lucchi, M L; Callegari, E; Draicchio, F

1987-12-01

Painful fibers running in the third nerve and originating from the ophthalmic trigeminal area send their central projections at level of substantia gelatinosa of nucleus caudalis trigemini. The central endings of these fibers form axoaxonic synapses with trigeminal fibers entering the brain stem through the trigeminal root. The effect of electrical stimulation of the third nerve central stump on the central endings of trigeminal afferent fibers consists in an increased excitability, possibly resulting in a presynaptic inhibition. This inhibitory influence is due to both direct and indirect connections of the third nerve afferent fibers with the trigeminal ones.

A precision mechanical nerve stimulator

NASA Technical Reports Server (NTRS)

Tcheng, Ping; Supplee, Frank H., Jr.; Prass, Richard L.

1988-01-01

An electromechanical device, used to apply and monitor stimulating pulses to a mammalian motor nerve, has been successfully developed at NASA Langley Research Center. Two existing force transducers, a flight skin friction balance and a miniature skin friction balance which were designed for making aerodynamic drag measurements, were modified and incorporated to form this precision instrument. The nerve stimulator is a type one servomechanism capable of applying and monitoring stimulating pulses of 0 to 10 grams with a precision of better than +/- 0.05 grams. Additionally, the device can be independently used to apply stimulating pulses by displacing the nerve from 0 to 0.25 mm with a precision of better than +/- 0.001 mm while measuring the level of the load applied.

Inferior alveolar nerve paresthesia after overfilling of endodontic sealer into the mandibular canal.

PubMed

González-Martín, Maribel; Torres-Lagares, Daniel; Gutiérrez-Pérez, José Luis; Segura-Egea, Juan José

2010-08-01

The present study describes a case of endodontic sealer (AH Plus) penetration within and along the mandibular canal from the periapical zone of a lower second molar after endodontic treatment. The clinical manifestations comprised anesthesia of the left side of the lower lip, paresthesia and anesthesia of the gums in the third quadrant, and paresthesia and anesthesia of the left mental nerve, appearing immediately after endodontic treatment. The paresthesia and anesthesia of the lip and gums were seen to decrease, but the mental nerve paresthesia and anesthesia persisted after 3.5 years. This case illustrates the need to expend great care with all endodontic techniques when performing nonsurgical root canal therapy, especially when the root apices are in close proximity to vital anatomic structures such as the inferior alveolar canal. Copyright 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

A randomized clinical trial of the effectiveness of mechanical traction for sub-groups of patients with low back pain: study methods and rationale

PubMed Central

2010-01-01

Background Patients with signs of nerve root irritation represent a sub-group of those with low back pain who are at increased risk of persistent symptoms and progression to costly and invasive management strategies including surgery. A period of non-surgical management is recommended for most patients, but there is little evidence to guide non-surgical decision-making. We conducted a preliminary study examining the effectiveness of a treatment protocol of mechanical traction with extension-oriented activities for patients with low back pain and signs of nerve root irritation. The results suggested this approach may be effective, particularly in a more specific sub-group of patients. The aim of this study will be to examine the effectiveness of treatment that includes traction for patients with low back pain and signs of nerve root irritation, and within the pre-defined sub-group. Methods/Design The study will recruit 120 patients with low back pain and signs of nerve root irritation. Patients will be randomized to receive an extension-oriented treatment approach, with or without the addition of mechanical traction. Randomization will be stratified based on the presence of the pre-defined sub-grouping criteria. All patients will receive 12 physical therapy treatment sessions over 6 weeks. Follow-up assessments will occur after 6 weeks, 6 months, and 1 year. The primary outcome will be disability measured with a modified Oswestry questionnaire. Secondary outcomes will include self-reports of low back and leg pain intensity, quality of life, global rating of improvement, additional healthcare utilization, and work absence. Statistical analysis will be based on intention to treat principles and will use linear mixed model analysis to compare treatment groups, and examine the interaction between treatment and sub-grouping status. Discussion This trial will provide a methodologically rigorous evaluation of the effectiveness of using traction for patients with low back pain and signs of nerve root irritation, and will examine the validity of a pre-defined sub-grouping hypothesis. The results will provide evidence to inform non-surgical decision-making for these patients. Trial Registration This trial has been registered with http://ClinicalTrials.gov: NCT00942227 PMID:20433733

Does pain relief by CT-guided indirect cervical nerve root injection with local anesthetics and steroids predict pain relief after decompression surgery for cervical nerve root compression?

PubMed

Antoniadis, Alexander; Dietrich, Tobias J; Farshad, Mazda

2016-10-01

The relationship of pain relief from a recently presented CT-guided indirect cervical nerve root injection with local anesthetics and steroids to surgical decompression as a treatment for single-level cervical radiculopathy is not clear. This retrospective study aimed to compare the immediate and 6-week post-injection effects to the short- and long-term outcomes after surgical decompression, specifically in regard to pain relief. Patients (n = 39, age 47 ± 10 years) who had undergone CT-guided indirect injection with local anesthetics and steroids as an initial treatment for single cervical nerve root radiculopathy and who subsequently needed surgical decompression were included retrospectively. Pain levels (VAS scores) were monitored before, immediately after, and 6 weeks after injection (n = 34), as well as 6 weeks (n = 38) and a mean of 25 months (SD ± 12) after surgical decompression (n = 36). Correlation analysis was performed to find potential associations of pain relief after injection and after surgery to investigate the predictive value of post-injection pain relief. There was no correlation between immediate pain relief after injection (-32 ± 27 %) and 6 weeks later (-7 ± 19 %), (r = -0.023, p = 0.900). There was an association by tendency between immediate pain relief after injection and post-surgical pain relief at 6 weeks (-82 ± 27 %), (r = 0.28, p = 0.08). Pain relief at follow-up remained high at -70 ± 21 % and was correlated with the immediate pain amelioration effect of the injection (r = 0.37, p = 0.032). Five out of seven patients who reported no pain relief from injection had a pain relief from surgery in excess of 50 %. The amount of immediate radiculopathic pain relief after indirect cervical nerve root injection is associated with the amount of pain relief achieved at long-term follow-up after surgical decompression of single-level cervical radiculopathy. Patients can still expect sufficient pain relief from surgery even if they did not respond to the cervical infiltration.

Effects of corticopuncture (CP) and low-level laser therapy (LLLT) on the rate of tooth movement and root resorption in rats using micro-CT evaluation.

PubMed

Suzuki, Selly Sayuri; Garcez, Aguinaldo Silva; Reese, Patricia Oblitas; Suzuki, Hideo; Ribeiro, Martha Simões; Moon, Won

2018-05-01

The aim of this study was to compare the rate of tooth displacement, quantity of root resorption, and alveolar bone changes in five groups: corticopuncture (CP), low-level laser therapy (LLLT), CP combined with LLLT (CP + LLLT), control (C), and negative control (NC). A total of 60 half-maxilla from 30 male Wistar rats (10 weeks old) were divided randomly into five groups: three (CP, LLLT, and CP + LLLT) test groups with different stimulation for accelerated-tooth-movement (ATM), one control (C) group, and one negative control (NC) group with no tooth movement. Nickel-titanium coil springs with 50 g of force were tied from the upper left and right first molars to micro-implants placed behind the maxillary incisors. For the CP and CP + LLLT groups, two perforations in the palate and one mesially to the molars were performed. For the LLLT and CP + LLLT groups, GaAlAs diode laser was applied every other day for 14 days (810 nm, 100 mW, 15 s). The tooth displacements were measured directly from the rat's mouth and indirectly from microcomputer (micro-CT) tomographic images. Bone responses at the tension and compression sites and root resorption were analyzed from micro-CT images. The resulting alveolar bone responses were evaluated by measuring bone mineral density (BMD), bone volume fraction (BV/TV), and trabecular thickness (TbTh). Root resorption crater volumes were measured on both compression and tension sides of mesial and distal buccal roots. The tooth displacement in the CP + LLLT group was the greatest when measured clinically, followed by the CP, LLLT, and control groups (C and NC), respectively (p <0.05). The tooth movements measured from micro-CT images showed statistically higher displacement in the CP and CP + LLLT groups compared to the LLLT and control groups. The BMD, BV/TV, and TbTh values were lower at the compression side and higher at the tension side for all three test groups compared to the control group. The root resorption crater volume of the distal buccal root was higher in the control group, followed by CP, LLLT, and CP + LLLT, mostly at the compression site. Combining corticopuncture and low-level laser therapy (CP + LLLT) produced more tooth displacement and less root resorption at the compression side. The combined technique also promoted higher alveolar bone formation at the tension side.

A Novel Collaborative Protocol for Successful Management of Penile Pain Mediated by Radiculitis of Sacral Spinal Nerve Roots From Tarlov Cysts.

PubMed

Goldstein, Irwin; Komisaruk, Barry R; Rubin, Rachel S; Goldstein, Sue W; Elliott, Stacy; Kissee, Jennifer; Kim, Choll W

2017-09-01

Since 14 years of age, the patient had experienced extreme penile pain within seconds of initial sexual arousal through masturbation. Penile pain was so severe that he rarely proceeded to orgasm or ejaculation. After 7 years of undergoing multiple unsuccessful treatments, he was concerned for his long-term mental health and for his future ability to have relationships. To describe a novel collaboration among specialists in sexual medicine, neurophysiology, and spine surgery that led to successful management. Collaborating health care providers conferred with the referring physician, patient, and parents and included a review of all medical records. Elimination of postpubertal intense penile pain during sexual arousal. The patient presented to our sexual medicine facility at 21 years of age. The sexual medicine physician identifying the sexual health complaint noted a pelvic magnetic resonance imaging report of an incidental sacral Tarlov cyst. A subsequent sacral magnetic resonance image showed four sacral Tarlov cysts, with the largest measuring 18 mm. Neuro-genital testing result were abnormal. The neurophysiologist hypothesized the patient's pain at erection was produced by Tarlov cyst-induced neuropathic irritation of sensory fibers that course within the pelvic nerve. The spine surgeon directed a diagnostic injection of bupivacaine to the sacral nerve roots and subsequently morphine to the conus medullaris of the spinal cord. The bupivacaine produced general penile numbness; the morphine selectively decreased penile pain symptoms during sexual arousal without blocking penile skin sensation. The collaboration among specialties led to the conclusion that the Tarlov cysts were pathophysiologically mediating the penile pain symptoms during arousal. Long-term follow-up after surgical repair showed complete symptom elimination at 18 months after treatment. This case provides evidence that (i) Tarlov cysts can cause sacral spinal nerve root radiculitis through sensory pelvic nerve and (ii) there are management benefits from collaboration among sexual medicine, neurophysiology, and spine surgery subspecialties. Goldstein I, Komisaruk BR, Rubin RS, et al. A Novel Collaborative Protocol for Successful Management of Penile Pain Mediated by Radiculitis of Sacral Spinal Nerve Roots From Tarlov Cysts. Sex Med 2017;5:e203-e211. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Different functional reorganization of motor cortex after transfer of the contralateral C7 to different recipient nerves in young rats with total brachial plexus root avulsion.

PubMed

Pan, Feng; Wei, Hai-feng; Chen, Liang; Gu, Yu-dong

2012-12-07

Clinically, contralateral C7 transfer is used for nerve reconstruction in brachial plexus injuries. Postoperatively, synchronous motions at the donor limb are noteworthy. This study studied if different recipient nerves influenced transhemispheric functional reorganization of motor cortex after this procedure. 90 young rats with total root avulsion of the brachial plexus were divided into groups 1-3 of contralateral C7 transfer to anterior division of the upper trunk, to both the musculocutaneous and median nerves, and to the median nerve, respectively. After reinnervation of target muscles, number of sites for forelimb representations in bilateral motor cortices was determined by intracortical microstimulation at 1.5, 3, 6, 9, and 12 months postoperatively. At nine months, transhemispheric reorganization of nerves neurotized by contralateral C7 was fulfilled in four of six rats in group 1, one of six in group 2 and none in group 3, respectively; at 12 months, that was fulfilled in five of six in group 1, four of six in groups 2 and 3, respectively. Logistic regression analysis showed that rate of fulfilled transhemispheric reorganization in group 1 was 12.19 times that in group 3 (95% CI 0.006-0.651, p=0.032). At 12 months, number of sites for hindlimb representations which had encroached upon original forelimb representations on the uninjured side was statistically more in group 3 than in group 2 (t=9.5, p<0.0001). It is concluded that contralateral C7 transfer to upper trunk or to both the musculocutaneous and median nerves induces faster transhemispheric functional reorganization of motor cortex than that to median nerve alone in rats. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Intradural extramedullary hemangiopericytoma of the thoracic spine infiltrating a nerve root: a case report and literature review.

PubMed

Moscovici, Samuel; Ramirez-DeNoriega, Fernando; Fellig, Yakov; Rosenthal, Guy; Cohen, José E; Itshayek, Eyal

2011-11-01

Review the presentation and diagnosis of an intradural extramedullary hemangiopericytoma of the thoracic spine. To present a rare case of intradural, subpial hemangiopericytoma in the thoracic spine, with a brief overview of the literature. Spinal intradural extramedullary hemangiopericytoma is rare entity that radiographically mimics nerve-sheath tumors. These lesions are typically diagnosed at surgery performed due to suspicion of tumor. A 20-year-old man who presented with back pain, leg weakness, and sphincter incontinence. MR imaging demonstrated an intradural extramedullary lesion at the T9-T10 level that was isointense on T1- and T2-weighted images and homogeneously enhancing after administration of gadolinium, with cystic components seen on T2-weighted images. The preoperative diagnosis was meningioma or schwannoma. At surgery, the lesion was bluish and completely subpial, with apparent nerve root invasion. Pathological examination revealed a neoplasm adjacent to a nerve root with possible focal infiltration. Abundant reticulin fibers and widened, branching vascular channels imparting a staghorn appearance were seen. Up to five mitotic figures were counted in one high-power field. On immunostaining, the neoplastic cells were diffusely immunoreactive for CD99 and immunonegative for EMA, CD34, and S-100 protein. The pathological diagnosis was consistent with anaplastic hemangiopericytoma, WHO grade III. This is the ninth report of spinal intradural hemangiopericytoma. The location of the neoplasm supports the hypothesis that hemangiopericytoma may arise from the spinal pial capillaries.

Ventilator waveforms on anesthesia machine: a simple tool for intraoperative mapping of phrenic nerve and mid-cervical roots.

PubMed

Georgoulis, George; Papagrigoriou, Eirini; Sindou, Marc

2015-12-01

A crucial aspect of surgery on the supraclavicular region, lateral neck, and mid-cervical vertebral region is the identification and sparing of the phrenic nerve and cervical (C4) root that are responsible for diaphragmatic innervation. Therefore intraoperative mapping of these nerve structures can be useful for difficult cases. Electrical stimulation with simultaneous observation of the ventilator waveforms of the anesthesia machine provides an effective method for the precise intraoperative mapping of these structures. In the literature, there is only one publication reporting the use of one of the waveforms (capnography) for this purpose. Capnography and pressure-time waveforms, two mandatory curves in anesthesiological monitoring, were studied under electrical stimulation of the phrenic nerve (one patient) and the C4 root (eight patients). The aim was to detect changes that would verify diaphragmatic contraction. No modifications in anesthesia or surgery and no additional maneuvers were required. In all patients, stimulation was followed by identifiable changes in the two waveforms, compatible with diaphragmatic contraction: acute reduction in amplitude on capnography and repetitive saw-like elevations on pressure-time curve. Frequency of patterns on pressure-time curve coincided with the frequency of stimulation; therefore the two recordings were complementary. This simple method proved effective in identifying the neural structures responsible for diaphragmatic function. We therefore suggest that it should be employed in the various types of surgery where these structures are at risk.

Vascular entrapment of the sciatic plexus causing catamenial sciatica and urinary symptoms.

PubMed

Lemos, Nucelio; Marques, Renato Moretti; Kamergorodsky, Gil; Ploger, Christine; Schor, Eduardo; Girão, Manoel J B C

2016-02-01

Pelvic congestion syndrome is a well-known cause of cyclic pelvic pain (Ganeshan et al., Cardiovasc Intervent Radiol 30(6):1105-11, 2007). What is much less well known is that dilated or malformed branches of the internal or external iliac vessels can entrap the nerves of the sacral plexus against the pelvic sidewalls, producing symptoms that are not commonly seen in gynecological practice, such as sciatica, or refractory urinary and anorectal dysfunction (Possover et al., Fertil Steril 95(2):756-8. 2011). The objective of this video is to explain and describe the symptoms suggestive of vascular entrapment of the sacral plexus, as well as the technique for the laparoscopic decompression of these nerves. Two anecdotal cases of intrapelvic vascular entrapment are used to review the anatomy of the lumbosacral plexus and demonstrate the laparoscopic surgical technique for decompression at two different sites, one on the sciatic nerve and one on the sacral nerve roots. After surgery, the patient with the sciatic entrapment showed full recovery of the sciatica and partial recovery of the myofascial pain. The patient with sacral nerve root entrapment showed full recovery with resolution of symptoms. The symptoms suggestive of intrapelvic nerve entrapment are: perineal pain or pain irradiating to the lower limbs in the absence of a spinal disorder, and lower urinary tract symptoms in the absence of prolapse of a bladder lesion. In the presence of such symptoms, the radiologist should provide specific MRI sequences of the intrapelvic portion of the sacral plexus and a team and equipment to expose and decompress the sacral nerves should be prepared.

Novel Model of Somatosensory Nerve Transfer in the Rat.

PubMed

Paskal, Adriana M; Paskal, Wiktor; Pelka, Kacper; Podobinska, Martyna; Andrychowski, Jaroslaw; Wlodarski, Pawel K

2018-05-09

Nerve transfer (neurotization) is a reconstructive procedure in which the distal denervated nerve is joined with a proximal healthy nerve of a less significant function. Neurotization models described to date are limited to avulsed roots or pure motor nerve transfers, neglecting the clinically significant mixed nerve transfer. Our aim was to determine whether femoral-to-sciatic nerve transfer could be a feasible model of mixed nerve transfer. Three Sprague Dawley rats were subjected to unilateral femoral-to-sciatic nerve transfer. After 50 days, functional recovery was evaluated with a prick test. At the same time, axonal tracers were injected into each sciatic nerve distally to the lesion site, to determine nerve fibers' regeneration. In the prick test, the rats retracted their hind limbs after stimulation, although the reaction was moderately weaker on the operated side. Seven days after injection of axonal tracers, dyes were visualized by confocal microscopy in the spinal cord. Innervation of the recipient nerve originated from higher segments of the spinal cord than that on the untreated side. The results imply that the femoral nerve axons, ingrown into the damaged sciatic nerve, reinnervate distal targets with a functional outcome.

The Effect of Weak Combined Magnetic Field on Root Gravitropism and a Role of Ca2+ Ions Therein

NASA Astrophysics Data System (ADS)

Kordyum, Elizabeth; Bogatina, Nina; Kondrachuk, A.

At present, magnetic fields of different types are widely used to study gravity sensing in plants. For instance, magnetic levitation of amyloplasts caused by high gradient magnetic field enables us to alter the effective gravity sensed by plant cells. For the first time we showed that a weak combined magnetic field (CMF), that is the sum of collinear permanent and alternating magnetic fields ( 0.5 gauss, 0-100 Hz), changes a cress and pea root positive gravitropic reaction on a negative one. This effect has the form of resonance and occurs at the frequency of cyclotron resonance of calcium ions. What is especially interesting is that under gravistimulation in the CMF, the displacement of amylopasts in the root cap statocytes is directed to the upper wall of a cell, i.e. in the direction opposite to the gravitational vector. The displacement of amyloplasts, which contain the abundance of free Ca2+ ions in the stroma, is accompanied by Ca2+ redistribution in the same direction, and increasing in the cytosol around amyloplasts near ten times in the CMF in comparison with the state magnetic field. Earlier, we also observed the Ca2+ accumulation in the upper site of a root curvature in the elongation zone in the CMF unlike a positive gravitropic reaction. Thus, it should be stressed that a root is bending in the same direction in which amyloplasts are displacing: downwards when gravitropism is positive and upwards when gravitropism is negative. The obtained data confirm the amyloplast statolithic function and give another striking demonstration of a leading role of Ca2+ ions in root gravitropism. But these data bring the question: what forces can promote amyloplast displacement against gravity? The possible explanation of the effect found is discussed. It is based on the ion cyclotron resonance in biosystems proposed by Liboff.. The original approach based on the use of a weak CMF may be helpful for understanding the mechanisms of plant gravisensing

Sacral nerve root neuromodulation: an effective treatment for refractory urge incontinence.

PubMed

Shaker, H S; Hassouna, M

1998-05-01

Sacral foramina implants have been recognized recently as a method for treatment of refractory urinary urge incontinence. We study the outcome of the procedure with in-depth analysis of the results of 18 implanted cases. Patients with urinary urge incontinence were subjected to percutaneous nerve evaluation of the S3 roots as a temporary screening test to determine response to neuromodulation. Satisfactory responders were implanted with permanent sacral root neuroprosthesis. The study design included comprehensive voiding diaries for 4 consecutive days twice as a baseline, 1 with percutaneous nerve evaluation screening, 1 after the percutaneous nerve evaluation, 1 at the 1, 3 and 6 post-implantation visits, and every 6 months thereafter. Uroflowmetry and quality of life questionnaires were performed at the same intervals. Urodynamic study was done as a baseline and 6 months after implantation of the neuroprosthesis. All 18 patients (16 women and 2 men) with refractory urge incontinence received a sacral foramina neuroprosthesis after demonstrating a good response to the percutaneous nerve evaluation. Average patient age at presentation was 42.3+/-3.3 years (range 22 to 67) and duration of urinary symptoms was 6.6+/-1.3 years (range 1.2 to 18.8). Average followup was 18.8 months (range 3 to 83). Neuromodulation in these patients showed a marked reduction in leakage episodes from 6.49 to 1.98 times per 24 hours and in the leakage severity score. Eight patients became completely dry and 4 had average leakage episodes of 1 or less daily. Patients showed as well a decrease in urinary frequency with an increase in functional bladder capacity. Associated pelvic pain improved substantially. Cystometrograms demonstrated increased volume at first sensation by 50% and increased cystometric capacity by 15% with the disappearance of uninhibited contractions in 1 of the 4 patients who presented with it preoperatively. There was also noticeable improvement in the quality of life. Complication rate was low and none was life threatening. Sacral root neuromodulation is an appealing modality for treatment of urge incontinence refractory to conventional pharmacotherapy. The relative simplicity of the technique, promising results and low complication rate make this therapy a likely alternative.

Spontaneous displacement of olecranon fracture through geode salvaged by elbow replacement.

PubMed

Jaiswal, Anuj; Thakur, Raman; Relwani, Jaikumar; Ogufere, Wallace

2010-04-01

We present a case of pathological fracture of olecranon through a giant geode. Fracture was initially undisplaced and was treated conservatively. It later progressed to a transolecranon dislocation as a result of a pseudarthrosis at the fracture site. The patient presented 4 years later when she developed symptoms of ulnar nerve palsy. She was treated by a total elbow arthroplasty with ulnar nerve transposition. The current report highlights this unusual case and reviews the relevant literature.

Differences in individual susceptibility affect the development of trigeminal neuralgia☆

PubMed Central

Duransoy, Yusuf Kurtuluş; Mete, Mesut; Akçay, Emrah; Selçuki, Mehmet

2013-01-01

Trigeminal neuralgia is a syndrome due to dysfunctional hyperactivity of the trigeminal nerve, and is characterized by a sudden, usually unilateral, recurrent lancinating pain arising from one or more divisions of the nerve. The most accepted pathogenetic mechanism for trigeminal neuralgia is compression of the nerve at its dorsal root entry zone or in its distal course. In this paper, we report four cases with trigeminal neuralgia due to an unknown mechanism after an intracranial intervention. The onset of trigeminal neuralgia after surgical interventions that are unrelated to the trigeminal nerve suggests that in patients with greater individual susceptibility, nerve contact with the vascular structure due to postoperative pressure and changes in cerebrospinal fluid flow may cause the onset of pain. PMID:25206428

Identification of Key Pathways and Genes in L4 Dorsal Root Ganglion (DRG) After Sciatic Nerve Injury via Microarray Analysis.

PubMed

Zhao, He; Duan, Li-Jun; Sun, Qing-Ling; Gao, Yu-Shan; Yang, Yong-Dong; Tang, Xiang-Sheng; Zhao, Ding-Yan; Xiong, Yang; Hu, Zhen-Guo; Li, Chuan-Hong; Chen, Si-Xue; Liu, Tao; Yu, Xing

2018-04-19

Peripheral nerve injury (PNI) has devastating consequences. Dorsal root ganglion as a pivotal locus participates in the process of neuropathic pain and nerve regeneration. In recent years, gene sequencing technology has seen rapid rise in the biomedicine field. So, we attempt to gain insight into in the mechanism of neuropathic pain and nerve regeneration in the transcriptional level and to explore novel genes through bioinformatics analysis. The gene expression profiles of GSE96051 were downloaded from GEO database. The gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes pathway (KEGG) enrichment analyses were performed, and protein-protein interaction (PPI) network of the differentially expressed genes (DEGs) was constructed by Cytoscape software. Our results showed that both IL-6 and Jun genes and the signaling pathway of MAPK, apoptosis, P53 present their vital modulatory role in nerve regeneration and neuropathic pain. Noteworthy, 13 hub genes associated with neuropathic pain and nerve regeneration, including Ccl12, Ppp1r15a, Cdkn1a, Atf3, Nts, Dusp1, Ccl7, Csf, Gadd45a, Serpine1, Timp1 were rarely reported in PubMed database, these genes may provide us the new orientation in experimental research and clinical study. Our results may provide more deep insight into the mechanism and a promising therapeutic target. The next step is to put our emphasis on an experiment level and to verify the novel genes from 13 hub genes.

The Macroanatomy of the Sacral Plexus and Its Nerves in Eurasian Eagle Owls (Bubo bubo).

PubMed

Akbulut, Y; Demiraslan, Y; Aslan, K; Coban, A

2016-10-01

This study was carried out to reveal the formation of the sacral plexus in the Eurasian Eagle Owls (Bubo bubo) and the nerves originating from this plexus. Five EEOs, three of them were male and two were female, were provided from Wildlife Rescue and Rehabilitation Center of Kafkas University and used as materials. Following the euthanizing of the animals, abdominal cavity was opened. The nerves of plexus sacrales were dissected and photographed. It was detected that the sacral plexus was formed by the ventral ramus of five synsacral nerves. Moreover, it was determined that the roots of the sacral plexus formed three trunks: the truncus cranialis, the truncus medius and the truncus caudalis in fossa renalis. The availability of the n. ischiofemoralis and the availability of n. parafibularis were detected in the EEOs. Five branches were specified as having segregated from the sacral plexus: the n. cutaneus femoralis caudalis, the mutual root of n. fibularis with n. tibialis (n. ischiadicus), the rami musculares, the n. coxalis caudalis and the ramus muscularis. It was observed that the sacral plexus was linked to the lumbar plexus by the n. furcalis, to the pudendus plexus via the n. bigeminus. Consequently, the anatomic structure of the EEO's sacral plexus, the participating synsacral nerves to plexus and the innervation areas of these nerves were revealed. © 2015 Blackwell Verlag GmbH.

Patterns of anomalies of structures of the middle ear and the facial nerve as revealed in newborn temporal bones.

PubMed

Tóth, Miklós; Sirirattanapan, Jarinratn; Mann, Wolf

2013-08-01

The purpose of this study is to offer new data about facial nerve malformations in the tympanic cavity. Prospective anatomic study of newborns to demonstrate the submacroscopic anatomy of the intratympanic facial nerve and its surrounding structures by malformations. Step-by-step microdissection of 12 newborn temporal bones and histologic evaluation of 4 middle ears showing multiple malformations. Four of 12 temporal bones presented malformation in the middle ear. All 4 temporal bones showed developmental failures of the stapes, and 3 of them had malposition of the tympanic portion of the facial nerve. In 3 cases, there was an oval window atresia, and in 1 case, the rim of the oval window was not ossified and was positioned medial to the stapes. Malformation or displacement of the stapes can be an indirect sign for facial nerve malformation. The most common site for facial nerve malformation is the tympanic portion. The tympanic segment of the nerve is devoid of bony covering in association with these anomalies of the stapes.

Haemangioblastoma of a cervical sensory nerve root in Von Hippel-Lindau syndrome.

PubMed

McEvoy, A W; Benjamin, E; Powell, M P

2000-10-01

Spinal haemangioblastomas are rare, accounting for only about 7% of all central nervous system cases. The case of a 40-year-old woman with a haemangioblastoma arising solely from a cervical sensory nerve root is presented. At operation via a cervical laminectomy, it was possible to resect the tumour en masse with the sensory ramus, by extending the laminectomy through the exit foramen for C6. Haemangioblastomas are commonly intramedullary, and have only been reported in this location on one previous occasion. The patient has Von Hippel-Lindau syndrome and a history of multiple solid tumours. The possible role of the Von Hippel-Lindau tumour suppressor gene in the pathogenesis of these neoplasms is discussed.

Double Crush of L5 Spinal Nerve Root due to L4/5 Lateral Recess Stenosis and Bony Spur Formation of Lumbosacral Transitional Vertebra Pseudoarticulation: A Case Report and Review

PubMed Central

Iwasaki, Motoyuki; Akiyama, Masahiko; Koyanagi, Izumi; Niiya, Yoshimasa; Ihara, Tatsuo; Houkin, Kiyohiro

2017-01-01

We present a case of double-crushed L5 nerve root symptoms caused by inside and outside of the spinal canal with spur formation of the lumbosacral transitional vertebra (LSTV). A 78-year-old man presented with 7-year history of moderate paresis of his toe and left leg pain when walking. Magnetic resonance imaging (MRI) revealed spinal stenosis at the L3/4 and 4/5 spinal levels and he underwent wide fenestration of both levels. Leg pain disappeared and 6-min walk distance (6MWD) improved after surgery, however, the numbness in his toes increased and 6MWD decreased 9 months after surgery. Repeated MR and 3D multiplanar reconstructed computed tomography (CT) images showed extraforaminal impingement of the L5 root by bony spur of the left LSTV. He underwent second decompression surgery of the L5/S via the left sided Wiltse approach, resulting in the improvement of his symptoms. The impingement of L5 spinal nerve root between the transverse process of the fifth lumbar vertebra and the sacral ala is a rare entity of the pathology called “far-out syndrome (FOS)”. Especially, the bony spur formation secondary to the anomalous articulation of the LSTV (LSPA) has not been reported. These articulations could be due to severe disc degeneration, following closer distance and contact between the transverse process and the sacral ala. To our knowledge, this is the first report describing a case with this pathology and may be considered in cases of failed back surgery syndromes (FBSS) of the L5 root symptoms. PMID:29018654

Salvage C2 ganglionectomy after C2 nerve root decompression provides similar pain relief as a single surgical procedure for intractable occipital neuralgia.

PubMed

Pisapia, Jared M; Bhowmick, Deb A; Farber, Roger E; Zager, Eric L

2012-02-01

To determine the effectiveness of C2 nerve root decompression and C2 dorsal root ganglionectomy for intractable occipital neuralgia (ON) and C2 ganglionectomy after pain recurrence following initial decompression. A retrospective review was performed of the medical records of patients undergoing surgery for ON. Pain relief at the time of the most recent follow-up was rated as excellent (headache relieved), good (headache improved), or poor (headache unchanged or worse). Telephone contact supplemented chart review, and patients rated their preoperative and postoperative pain on a 10-point numeric scale. Patient satisfaction and disability were also examined. Of 43 patients, 29 were available for follow-up after C2 nerve root decompression (n = 11), C2 dorsal root ganglionectomy (n = 10), or decompression followed by ganglionectomy (n = 8). Overall, 19 of 29 patients (66%) experienced a good or excellent outcome at most recent follow-up. Among the 19 patients who completed the telephone questionnaire (mean follow-up 5.6 years), patients undergoing decompression, ganglionectomy, or decompression followed by ganglionectomy experienced similar outcomes, with mean pain reduction ratings of 5 ± 4.0, 4.5 ± 4.1, and 5.7 ± 3.5. Of 19 telephone responders, 13 (68%) rated overall operative results as very good or satisfactory. In the third largest series of surgical intervention for ON, most patients experienced favorable postoperative pain relief. For patients with pain recurrence after C2 decompression, salvage C2 ganglionectomy is a viable surgical option and should be offered with the potential for complete pain relief and improved quality of life (QOL). Copyright © 2012. Published by Elsevier Inc.

The spinal cord and its roots according to Galen.

PubMed

Viale, Giuseppe L

2004-06-01

Galen's methodological approach to medicine anticipated modern rules. His experiments on the spinal cord contributed greatly to our knowledge of this structure by reporting the variegated pattern of neurological impairment after sectioning at different levels. His approach to injuries of the spinal roots and peripheral nerves documents both diagnostic skill and intellectual honesty.

The anterolateral acromial approach for fractures of the proximal humerus.

PubMed

Gardner, Michael J; Boraiah, Sreevathsa; Helfet, David L; Lorich, Dean G

2008-02-01

Displaced and unstable fractures of the proximal humerus are notoriously difficult to manage. Successful surgical treatment requires finding the appropriate balance between adequate exposure for reduction and rigid fixation and minimizing soft tissue dissection. The anterolateral acromial approach was developed to allow less invasive treatment of proximal humerus fractures. The plane of the avascular anterior deltoid raphe is utilized, and the axillary nerve is identified and protected. Anterior dissection near the critical blood supply is avoided, substantial muscle retraction is minimized, and the lateral plating zone is directly accessed. Over a 4-year period, 52 patients with acute displaced fractures of the proximal humerus were treated with the anterolateral acromial approach and either a locking plate or an intramedullary nail. Twenty-three patients were evaluated clinically at a minimum follow-up of 1 year (average, 28 months) by clinical examination for range of motion and nerve function and a QuickDASH score. There were no axillary nerve deficits postoperatively related to the approach, and the average QuickDASH score was 25.2 (0, best; 100, worst). This approach allowed direct access to the lateral fracture planes for fracture reduction and plate placement or safe nail and interlocking screw placement.

Effective gene expression in the rat dorsal root ganglia with a non-viral vector delivered via spinal nerve injection

PubMed Central

Chang, Ming-Fong; Hsieh, Jung-Hsien; Chiang, Hao; Kan, Hung-Wei; Huang, Cho-Min; Chellis, Luke; Lin, Bo-Shiou; Miaw, Shi-Chuen; Pan, Chun-Liang; Chao, Chi-Chao; Hsieh, Sung-Tsang

2016-01-01

Delivering gene constructs into the dorsal root ganglia (DRG) is a powerful but challenging therapeutic strategy for sensory disorders affecting the DRG and their peripheral processes. The current delivery methods of direct intra-DRG injection and intrathecal injection have several disadvantages, including potential injury to DRG neurons and low transfection efficiency, respectively. This study aimed to develop a spinal nerve injection strategy to deliver polyethylenimine mixed with plasmid (PEI/DNA polyplexes) containing green fluorescent protein (GFP). Using this spinal nerve injection approach, PEI/DNA polyplexes were delivered to DRG neurons without nerve injury. Within one week of the delivery, GFP expression was detected in 82.8% ± 1.70% of DRG neurons, comparable to the levels obtained by intra-DRG injection (81.3% ± 5.1%, p = 0.82) but much higher than those obtained by intrathecal injection. The degree of GFP expression by neurofilament(+) and peripherin(+) DRG neurons was similar. The safety of this approach was documented by the absence of injury marker expression, including activation transcription factor 3 and ionized calcium binding adaptor molecule 1 for neurons and glia, respectively, as well as the absence of behavioral changes. These results demonstrated the efficacy and safety of delivering PEI/DNA polyplexes to DRG neurons via spinal nerve injection. PMID:27748450

Upregulation of EMMPRIN (OX47) in Rat Dorsal Root Ganglion Contributes to the Development of Mechanical Allodynia after Nerve Injury.

PubMed

Wang, Qun; Sun, Yanyuan; Ren, Yingna; Gao, Yandong; Tian, Li; Liu, Yang; Pu, Yanan; Gou, Xingchun; Chen, Yanke; Lu, Yan

2015-01-01

Matrix metalloproteinases (MMPs) are widely implicated in inflammation and tissue remodeling associated with various neurodegenerative diseases and play an important role in nociception and allodynia. Extracellular Matrix Metalloproteinase Inducer (EMMPRIN) plays a key regulatory role for MMP activities. However, the role of EMMPRIN in the development of neuropathic pain is not clear. Western blotting, real-time quantitative RT-PCR (qRT-PCR), and immunofluorescence were performed to determine the changes of messenger RNA and protein of EMMPRIN/OX47 and their cellular localization in the rat dorsal root ganglion (DRG) after nerve injury. Paw withdrawal threshold test was examined to evaluate the pain behavior in spinal nerve ligation (SNL) model. The lentivirus containing OX47 shRNA was injected into the DRG one day before SNL. The expression level of both mRNA and protein of OX47 was markedly upregulated in ipsilateral DRG after SNL. OX47 was mainly expressed in the extracellular matrix of DRG. Administration of shRNA targeted against OX47 in vivo remarkably attenuated mechanical allodynia induced by SNL. In conclusion, peripheral nerve injury induced upregulation of OX47 in the extracellular matrix of DRG. RNA interference against OX47 significantly suppressed the expression of OX47 mRNA and the development of mechanical allodynia. The altered expression of OX47 may contribute to the development of neuropathic pain after nerve injury.

HSV-mediated gene transfer of vascular endothelial growth factor to dorsal root ganglia prevents diabetic neuropathy

PubMed Central

Chattopadhyay, M; Krisky, D; Wolfe, D; Glorioso, JC; Mata, M; Fink, DJ

2005-01-01

We examined the utility of herpes simplex virus (HSV) vector-mediated gene transfer of vascular endothelial growth factor (VEGF) in a mouse model of diabetic neuropathy. A replication-incompetent HSV vector with VEGF under the control of the HSV ICP0 promoter (vector T0VEGF) was constructed. T0VEGF expressed and released VEGF from primary dorsal root ganglion (DRG) neurons in vitro, and following subcutaneous inoculation in the foot, expressed VEGF in DRG and nerve in vivo. At 2 weeks after induction of diabetes, subcutaneous inoculation of T0VEGF prevented the reduction in sensory nerve amplitude characteristic of diabetic neuropathy measured 4 weeks later, preserved autonomic function measured by pilocarpine-induced sweating, and prevented the loss of nerve fibers in the skin and reduction of neuropeptide calcitonin gene-related peptide and substance P in DRG neurons of the diabetic mice. HSV-mediated transfer of VEGF to DRG may prove useful in treatment of diabetic neuropathy. PMID:15843809

Intercellular junctions between palisade nerve endings and outer root sheath cells of rat vellus hairs.

PubMed

Kaidoh, T; Inoué, T

2000-05-15

Hair follicles have a longitudinal set of sensory nerve endings called palisade nerve endings (PN). We examined the junctional structures between the PN and outer root sheath (ORS) cells of hair follicles in the rat external ear. Transmission electron microscopy of serial thin sections showed that the processes of the ORS cells penetrated the basal lamina of the hair follicle, forming intercellular junctions with the PN (PN-ORS junctions). Two types of junctions were found: junctions between nerve endings and ORS cells (N-ORS junctions) and those between Schwann cell processes and ORS cells (S-ORS junctions). The N-ORS junctions had two subtypes: 1) a short process or small eminence of the ORS cell was attached to the nerve ending (type I); or 2) a process of the ORS cell was invaginated into the nerve ending (type II). The S-ORS junctions also had two subtypes: 1) a short process or small eminence of the ORS cell was abutted on the Schwann cell process (type I); or 2) a process of the ORS cell was invaginated into the Schwann cell process (type II). Vesicles, coated pits, coated vesicles, and endosomes were sometimes seen in nerve endings, Schwann cells, and ORS cells near the junctions. Computer-aided reconstruction of the serial thin sections displayed the three-dimensional structure of these junctions. These results suggested that the PN-ORS junctions provided direct relationships between the PN and ORS in at least four different patterns. The discovery of these junctions shows the PN-ORS relationship to be closer than previously realized. We speculate that these junctions may have roles in attachment of the PN to the ORS, contributing to increases in the sensitivity of the PN, and in chemical signaling between the PN and ORS.

Cell- and stage-specific localization of galectin-3, a β-galactoside-binding lectin, in a mouse model of experimental autoimmune encephalomyelitis.

PubMed

Itabashi, Tetsuya; Arima, Yasunobu; Kamimura, Daisuke; Higuchi, Kotaro; Bando, Yoshio; Takahashi-Iwanaga, Hiromi; Murakami, Masaaki; Watanabe, Masahiko; Iwanaga, Toshihiko; Nio-Kobayashi, Junko

2018-06-16

Multiple sclerosis (MS) is an autoimmune disease in which pathogenic T cells play an important role, and an experimental autoimmune encephalomyelitis (EAE) is used as an animal model of MS. Galectins are β-galactoside-binding lectins and involved in various physiological and pathological events. Among fifteen members of galectins, galectin-1, -8, and -9 play immunosuppressive roles in MS and EAE; however, the role of galectin-3 (gal-3) is complex and controversial. We examined expression of gal-3 in the spinal cord and nerve roots of EAE mice. No immunohistochemical signals were detected in naïve mice, whereas gal-3 appeared at lower lumbar levels of the spinal cord and nerve roots in EAE mice. In the spinal cord, gal-3-positive cells were activated microglia and/or infiltrating macrophages, which were round in shape and intensified for the lysosomal enzyme, cathepsin D, indicating elevated phagocytic activity. Gal-3-positive cells in the spinal cord were most abundant during the peak symptomatic period. In the recovery period, they disappeared from the spinal parenchyma but remained at moderate levels in the pia mater. Interestingly, gal-3-positive cells selectively appeared in ventral, but not dorsal, nerve roots running through the spinal canal, with expression peaking during the recovery period. In ventral nerve roots, the major cell type expressing gal-3 was a specific population of Schwann cells that surround unmyelinated axons and express the biosynthetic enzyme for l-serine, a potent neurotrophic amino acid. Gal-3 was also induced in Iba1/F4/80-positive macrophages, which engulf damaged myelin and axon debris. Thus, gal-3 is induced in distinct cell types that are engaged in removal of damaged axons and cell debris and axon regeneration and remyelination, suggesting a potential neuroprotective role of gal-3 in EAE mice. Copyright © 2018. Published by Elsevier Ltd.

Diffusion Tensor Imaging of Lumbar Nerve Roots: Comparison Between Fast Readout-Segmented and Selective-Excitation Acquisitions.

PubMed

Manoliu, Andrei; Ho, Michael; Nanz, Daniel; Piccirelli, Marco; Dappa, Evelyn; Klarhöfer, Markus; Del Grande, Filippo; Kuhn, Felix Pierre

2016-08-01

The aim of this study was to compare the quality of recently emerged advanced diffusion tensor imaging (DTI) techniques with conventional single-shot echo-planar imaging (EPI) in a functional assessment of lumbar nerve roots. The institutional review board approved the study including 12 healthy volunteers. Diffusion tensor imaging was performed at 3 T (MAGNETOM Skyra; Siemens Healthcare) with b-values of 0 and 700 s/mm and an isotropic spatial resolution for subsequent multiplanar reformatting. The nerve roots L2 to S1 were imaged in coronal orientation with readout-segmented EPI (rs-DTI) and selective-excitation EPI (sTX-DTI) with an acquisition time of 5 minutes each, and in axial orientation with single-shot EPI (ss-DTI) with an acquisition time of 12 minutes (scan parameters as in recent literature). Two independent readers qualitatively and quantitatively assessed image quality. The interobserver reliability ranged from "substantial" to "almost perfect" for all examined parameter and all 3 sequences (κ = 0.70-0.94). Overall image quality was rated higher, and artifact levels were scored lower for rs-DTI and sTX-DTI than for ss-DTI (P = 0.007-0.027), while fractional anisotropy and signal-to-noise ratio values were similar for all sequences (P ≥ 0.306 and P ≥ 0.100, respectively). Contrast-to-noise ratios were significantly higher for rs-DTI and ss-DTI than for sTX-DTI (P = 0.004-0.013). Despite shorter acquisition times, rs-DTI and sTX-DTI produced images of higher quality with smaller geometrical distortions than the current standard of reference, ss-DTI. Thus, DTI acquisitions in the coronal plane, requiring fewer slices for full coverage of exiting nerve roots, may allow for functional neurography in scan times suitable for routine clinical practice.

miRNA Expression Change in Dorsal Root Ganglia After Peripheral Nerve Injury.

PubMed

Chang, Hsueh-Ling; Wang, Hung-Chen; Chunag, Yi-Ta; Chou, Chao-Wen; Lin, I-Ling; Lai, Chung-Sheng; Chang, Lin-Li; Cheng, Kuang-I

2017-02-01

The role of microRNAs (miRNAs) in the regulation of nerve injury-induced neuropathic pain is unclear. The aims of this study were to assess and compare miRNA expression profiles in dorsal root ganglia (DRG) following three different kinds of peripheral nerve injury, including spinal nerve ligation (SNL), dorsal root transection (DRT), and ventral root transection (VRT), in Sprague-Dawley rats. Responses to thermal and mechanical stimuli were measured preoperatively and on postoperative days (PODs) 1, 4, and 7. A miRNA microarray analysis was used to detect the miRNA expression profiles in injured L5 DRG from SNL, DRT, and VRT on POD 7. Validation of miRNA expression was performed by qPCR and in situ hybridization. Rats receiving SNL displayed significantly higher mechanical hypersensitivity, but those receiving DRT developed higher thermal hypersensitivity. The number of miRNAs that were significantly upregulated in L5 DRG was 49 (7.2%), 25 (3.7%), and 146 (21.5%) following SNL, DRT, and VRT, respectively. On the other hand, 35 (5.1%) miRNAs were significantly downregulated in the SNL group, 21 (3.1%) miRNAs in the DRT group, and 41 (6.0%) miRNAs in the VRT group. Of the four miRNAs that were mutually aberrant in all three models, two were significantly upregulated (twofold), miR-21 and miR-31, and two were significantly downregulated, miR-668 and miR-672. Using in situ hybridization, miRNA-21, miRNA-31, miRNA-668, and miRNA-672 were found to localize to neurons in the DRG. Collectively, the mutual abnormal miRNA expression of miR-21, miR-31, miR-668, and miR-677 implied that these miRNAs may be therapeutic targets for alleviating multiple forms of neuropathic pain.

Phrenic nerve transfer to the musculocutaneous nerve for the repair of brachial plexus injury: electrophysiological characteristics

PubMed Central

Liu, Ying; Xu, Xun-cheng; Zou, Yi; Li, Su-rong; Zhang, Bin; Wang, Yue

2015-01-01

Phrenic nerve transfer is a major dynamic treatment used to repair brachial plexus root avulsion. We analyzed 72 relevant articles on phrenic nerve transfer to repair injured brachial plexus that were indexed by Science Citation Index. The keywords searched were brachial plexus injury, phrenic nerve, repair, surgery, protection, nerve transfer, and nerve graft. In addition, we performed neurophysiological analysis of the preoperative condition and prognosis of 10 patients undergoing ipsilateral phrenic nerve transfer to the musculocutaneous nerve in our hospital from 2008 to 201 3 and observed the electromyograms of the biceps brachii and motor conduction function of the musculocutaneous nerve. Clinically, approximately 28% of patients had brachial plexus injury combined with phrenic nerve injury, and injured phrenic nerve cannot be used as a nerve graft. After phrenic nerve transfer to the musculocutaneous nerve, the regenerated potentials first appeared at 3 months. Recovery of motor unit action potential occurred 6 months later and became more apparent at 12 months. The percent of patients recovering ‘excellent’ and ‘good’ muscle strength in the biceps brachii was 80% after 18 months. At 12 months after surgery, motor nerve conduction potential appeared in the musculocutaneous nerve in seven cases. These data suggest that preoperative evaluation of phrenic nerve function may help identify the most appropriate nerve graft in patients with an injured brachial plexus. The functional recovery of a transplanted nerve can be dynamically observed after the surgery. PMID:25883637

Phrenic nerve transfer to the musculocutaneous nerve for the repair of brachial plexus injury: electrophysiological characteristics.

PubMed

Liu, Ying; Xu, Xun-Cheng; Zou, Yi; Li, Su-Rong; Zhang, Bin; Wang, Yue

2015-02-01

Phrenic nerve transfer is a major dynamic treatment used to repair brachial plexus root avulsion. We analyzed 72 relevant articles on phrenic nerve transfer to repair injured brachial plexus that were indexed by Science Citation Index. The keywords searched were brachial plexus injury, phrenic nerve, repair, surgery, protection, nerve transfer, and nerve graft. In addition, we performed neurophysiological analysis of the preoperative condition and prognosis of 10 patients undergoing ipsilateral phrenic nerve transfer to the musculocutaneous nerve in our hospital from 2008 to 201 3 and observed the electromyograms of the biceps brachii and motor conduction function of the musculocutaneous nerve. Clinically, approximately 28% of patients had brachial plexus injury combined with phrenic nerve injury, and injured phrenic nerve cannot be used as a nerve graft. After phrenic nerve transfer to the musculocutaneous nerve, the regenerated potentials first appeared at 3 months. Recovery of motor unit action potential occurred 6 months later and became more apparent at 12 months. The percent of patients recovering 'excellent' and 'good' muscle strength in the biceps brachii was 80% after 18 months. At 12 months after surgery, motor nerve conduction potential appeared in the musculocutaneous nerve in seven cases. These data suggest that preoperative evaluation of phrenic nerve function may help identify the most appropriate nerve graft in patients with an injured brachial plexus. The functional recovery of a transplanted nerve can be dynamically observed after the surgery.

Thermally Drawn Fibers as Nerve Guidance Scaffolds

PubMed Central

Koppes, Ryan A.; Park, Seongjun; Hood, Tiffany; Jia, Xiaoting; Poorheravi, Negin Abdolrahim; Achyuta, Anilkumar Harapanahalli; Fink, Yoel; Anikeeva, Polina

2016-01-01

Synthetic neural scaffolds hold promise to eventually replace nerve autografts for tissue repair following peripheral nerve injury. Despite substantial evidence for the influence of scaffold geometry and dimensions on the rate of axonal growth, systematic evaluation of these parameters remains a challenge due to limitations in materials processing. We have employed fiber drawing to engineer a wide spectrum of polymer-based neural scaffolds with varied geometries and core sizes. Using isolated whole dorsal root ganglia as an in vitro model system we have identified key features enhancing nerve growth within these fiber scaffolds. Our approach enabled straightforward integration of microscopic topography at the scale of nerve fascicles within the scaffold cores, which led to accelerated Schwann cell migration, as well as neurite growth and alignment. Our findings indicate that fiber drawing provides a scalable and versatile strategy for producing nerve guidance channels capable of controlling direction and accelerating the rate of axonal growth. PMID:26717246

Multiple locations of nerve compression: an unusual cause of persistent lower limb paresthesia.

PubMed

Ang, Chia-Liang; Foo, Leon Siang Shen

2014-01-01

A paucity of appreciation exists that the "double crush" phenomenon can account for persistent leg symptoms even after spinal neural decompression surgery. We present an unusual case of multiple locations of nerve compression causing persistent lower limb paresthesia in a 40-year old male patient. The patient's lower limb paresthesia was persistent after an initial spinal surgery to treat spinal lateral recess stenosis thought to be responsible for the symptoms. It was later discovered that he had peroneal muscle herniations that had caused superficial peroneal nerve entrapments at 2 separate locations. The patient obtained much symptomatic relief after decompression of the peripheral nerve. The "double crush" phenomenon and multiple levels of nerve compression should be considered when evaluating lower limb neurogenic symptoms, especially after spinal nerve root surgery. Copyright © 2014 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

Computational comparison of aortic root stresses in presence of stentless and stented aortic valve bio-prostheses.

PubMed

Nestola, M G C; Faggiano, E; Vergara, C; Lancellotti, R M; Ippolito, S; Antona, C; Filippi, S; Quarteroni, A; Scrofani, R

2017-02-01

We provide a computational comparison of the performance of stentless and stented aortic prostheses, in terms of aortic root displacements and internal stresses. To this aim, we consider three real patients; for each of them, we draw the two prostheses configurations, which are characterized by different mechanical properties and we also consider the native configuration. For each of these scenarios, we solve the fluid-structure interaction problem arising between blood and aortic root, through Finite Elements. In particular, the Arbitrary Lagrangian-Eulerian formulation is used for the numerical solution of the fluid-dynamic equations and a hyperelastic material model is adopted to predict the mechanical response of the aortic wall and the two prostheses. The computational results are analyzed in terms of aortic flow, internal wall stresses and aortic wall/prosthesis displacements; a quantitative comparison of the mechanical behavior of the three scenarios is reported. The numerical results highlight a good agreement between stentless and native displacements and internal wall stresses, whereas higher/non-physiological stresses are found for the stented case.

Preparation of the apical part of the root canal by the Lightspeed and step-back techniques.

PubMed

Portenier, I; Lutz, F; Barbakow, F

1998-03-01

This study measured in vitro the displacement of natural canal centres in 18 human teeth before and after shaping by the step-back or Lightspeed techniques. Experimental roots (n = 9 per group), embedded in clear plastic, were cross-sectioned using a 0.1-mm-thick band saw at distances 1.25 mm, 3.25 mm and 5.25 mm from the apices. A stereo microscope was used to take 35 mm slides of the cut surfaces of the sectioned roots and canals. The slides of the uninstrumented canals were scanned into a computer and saved. Each sectioned root was then reassembled and the canals shaped by the step-back or Lightspeed technique. File size 40 and instrument size 50 were selected as the master apical file and master apical rotary for the step-back and Lightspeed groups, respectively. The 18 prepared canals were photographed, and the 35 mm slides scanned and computer stored as previously. This allowed the positions of the pre- and postinstrumented roots to be electronically superimposed for subsequent analyses. Displacements of the root canal centres before and after preparation were assessed in relation to the cross-sectional diameter of the files or instruments used. In addition, increases in cross-sectional area of the root canals after preparation were evaluated in relation to the cross-sectional area of the files or instruments used. Engine-driven nickel-titanium Lightspeed instruments caused significantly less (P < 0.001) displacement of the canal centres, so roots in the Lightspeed group remained better centred than those in the step-back group. The mean cross-sectional area after preparation in the Lightspeed group was significantly less (P < 0.001) than that recorded in the step-back group. Clinically, this implies less apical transportation and less dentine destruction with the Lightspeed technique than with the step-back technique.

Effect of nerve injury on the number of dorsal root ganglion neurons and autotomy behavior in adult Bax-deficient mice.

PubMed

Lyu, Chuang; Lyu, Gong-Wei; Martinez, Aurora; Shi, Tie-Jun Sten

2017-01-01

The proapoptotic molecule BAX, plays an important role in mitochondrial apoptotic pathway. Dorsal root ganglion (DRG) neurons depend on neurotrophic factors for survival at early developmental stages. Withdrawal of neurotrophic factors will induce apoptosis in DRG neurons, but this type of cell death can be delayed or prevented in neonatal Bax knockout (KO) mice. In adult animals, evidence also shows that DRG neurons are less dependent upon neurotrophic factors for survival. However, little is known about the effect of Bax deletion on the survival of normal and denervated DRG neurons in adult mice. A unilateral sciatic nerve transection was performed in adult Bax KO mice and wild-type (WT) littermates. Stereological method was employed to quantify the number of lumbar-5 DRG neurons 1 month post-surgery. Nerve injury-induced autotomy behavior was also examined on days 1, 3, and 7 post-surgery. There were significantly more neurons in contralateral DRGs of KO mice as compared with WT mice. The number of neurons was reduced in ipsilateral DRGs in both KO and WT mice. No changes in size distributions of DRG neuron profiles were detected before or after nerve injury. Injury-induced autotomy behavior developed much earlier and was more serious in KO mice. Although postnatal death or loss of DRG neurons is partially prevented by Bax deletion, this effect cannot interfere with long-term nerve injury-induced neuronal loss. The exaggerated self-amputation behavior observed in the mutant mice indicates that Bax deficiency may enhance the development of spontaneous pain following nerve injury.

Computed Tomography Cisternography for Evaluation of Trigeminal Neuralgia When Magnetic Resonance Imaging Is Contraindicated: Case Report and Review of the Literature.

PubMed

Gospodarev, Vadim; Chakravarthy, Vikram; Harms, Casey; Myers, Hannah; Kaplan, Brett; Kim, Esther; Pond, Matthew; De Los Reyes, Kenneth

2018-05-01

Trigeminal neuralgia (TGN) causes severe unilateral facial pain. The etiology is hypothesized to be segmental demyelination of the trigeminal nerve root via compression by the superior cerebellar artery (SCA). Microvascular decompression (MVD) allows immediate and long-term pain relief. Preoperative evaluation includes magnetic resonance imaging (MRI) and/or magnetic resonance angiography of the brain. Having a pacemaker is a contraindication for MRI. There have been isolated reports of using computed tomography (CT) cisternography scans for radiation planning for TGN. A 75-year-old male with a permanent pacemaker who had refractory TGN in the V2 (maxillary) distribution of the trigeminal nerve underwent CT cisternography to prepare for MVD. CT angiography with Isovue 370 intravenous contrast injection and 0.625-mm axial images were obtained from the skull base across the posterior fossa. An intrathecal injection of Isovue 180 was performed at the L2/3 level. Imaging revealed the right SCA abutting the medial margin of the proximal right trigeminal nerve. In surgery (K.D.), a standard retrosigmoid suboccipital craniotomy was performed to access the cerebellopontine angle and separate the abutting SCA and trigeminal nerve. The patient had immediate pain relief. MRI is the preferred method of evaluating for TGN because it offers excellent visualization of vasculature in relation to the trigeminal nerve without accompanying radiation exposure. However, for patients who have contraindications to MRI, CT cisternography is shown to also be an effective method for visualizing the trigeminal root entry zone and nearby vasculature in preparation for MVD of the trigeminal nerve. Published by Elsevier Inc.

Cupping in the Monkey Optic Nerve Transection Model Consists of Prelaminar Tissue Thinning in the Absence of Posterior Laminar Deformation

PubMed Central

Ing, Eliesa; Ivers, Kevin M.; Yang, Hongli; Gardiner, Stuart K.; Reynaud, Juan; Cull, Grant; Wang, Lin; Burgoyne, Claude F.

2016-01-01

Purpose To use optical coherence tomography (OCT) to test the hypothesis that optic nerve head (ONH) “cupping” in the monkey optic nerve transection (ONT) model does not include posterior laminar deformation. Methods Five monkeys (aged 5.5–7.8 years) underwent ONH and retinal nerve fiber layer (RNFL) OCT imaging five times at baseline and biweekly following unilateral ONT until euthanization at ∼40% RNFL loss. Retinal nerve fiber layer thickness (RNFLT) and minimum rim width (MRW) were calculated from each pre- and post-ONT imaging session. The anterior lamina cribrosa surface (ALCS) was delineated within baseline and pre-euthanasia data sets. Significant ONT versus control eye pre-euthanasia change in prelaminar tissue thickness (PLTT), MRW, RNFLT, and ALCS depth (ALCSD) was determined using a linear mixed-effects model. Eye-specific change in each parameter exceeded the 95% confidence interval constructed from baseline measurements. Results Animals were euthanized 49 to 51 days post ONT. Overall ONT eye change from baseline was significant for MRW (−26.2%, P = 0.0011), RNFLT (−43.8%, P < 0.0001), PLTT (−23.8%, P = 0.0013), and ALCSD (−20.8%, P = 0.033). All five ONT eyes demonstrated significant eye-specific decreases in MRW (−23.7% to −31.8%) and RNFLT (−39.6% to −49.7%). Four ONT eyes showed significant PLTT thinning (−23.0% to −28.2%). The ALCS was anteriorly displaced in three of the ONT eyes (−25.7% to −39.2%). No ONT eye demonstrated posterior laminar displacement. Conclusions Seven weeks following surgical ONT in the monkey eye, ONH cupping involves prelaminar and rim tissue thinning without posterior deformation of the lamina cribrosa. PMID:27168368

Rehabilitation, Using Guided Cerebral Plasticity, of a Brachial Plexus Injury Treated with Intercostal and Phrenic Nerve Transfers.

PubMed

Dahlin, Lars B; Andersson, Gert; Backman, Clas; Svensson, Hampus; Björkman, Anders

2017-01-01

Recovery after surgical reconstruction of a brachial plexus injury using nerve grafting and nerve transfer procedures is a function of peripheral nerve regeneration and cerebral reorganization. A 15-year-old boy, with traumatic avulsion of nerve roots C5-C7 and a non-rupture of C8-T1, was operated 3 weeks after the injury with nerve transfers: (a) terminal part of the accessory nerve to the suprascapular nerve, (b) the second and third intercostal nerves to the axillary nerve, and (c) the fourth to sixth intercostal nerves to the musculocutaneous nerve. A second operation-free contralateral gracilis muscle transfer directly innervated by the phrenic nerve-was done after 2 years due to insufficient recovery of the biceps muscle function. One year later, electromyography showed activation of the biceps muscle essentially with coughing through the intercostal nerves, and of the transferred gracilis muscle by deep breathing through the phrenic nerve. Voluntary flexion of the elbow elicited clear activity in the biceps/gracilis muscles with decreasing activity in intercostal muscles distal to the transferred intercostal nerves (i.e., corresponding to eighth intercostal), indicating cerebral plasticity, where neural control of elbow flexion is gradually separated from control of breathing. To restore voluntary elbow function after nerve transfers, the rehabilitation of patients operated with intercostal nerve transfers should concentrate on transferring coughing function, while patients with phrenic nerve transfers should focus on transferring deep breathing function.

End-to-side neurorrhaphy repairs peripheral nerve injury: sensory nerve induces motor nerve regeneration.

PubMed

Yu, Qing; Zhang, She-Hong; Wang, Tao; Peng, Feng; Han, Dong; Gu, Yu-Dong

2017-10-01

End-to-side neurorrhaphy is an option in the treatment of the long segment defects of a nerve. It involves suturing the distal stump of the disconnected nerve (recipient nerve) to the side of the intimate adjacent nerve (donor nerve). However, the motor-sensory specificity after end-to-side neurorrhaphy remains unclear. This study sought to evaluate whether cutaneous sensory nerve regeneration induces motor nerves after end-to-side neurorrhaphy. Thirty rats were randomized into three groups: (1) end-to-side neurorrhaphy using the ulnar nerve (mixed sensory and motor) as the donor nerve and the cutaneous antebrachii medialis nerve as the recipient nerve; (2) the sham group: ulnar nerve and cutaneous antebrachii medialis nerve were just exposed; and (3) the transected nerve group: cutaneous antebrachii medialis nerve was transected and the stumps were turned over and tied. At 5 months, acetylcholinesterase staining results showed that 34% ± 16% of the myelinated axons were stained in the end-to-side group, and none of the myelinated axons were stained in either the sham or transected nerve groups. Retrograde fluorescent tracing of spinal motor neurons and dorsal root ganglion showed the proportion of motor neurons from the cutaneous antebrachii medialis nerve of the end-to-side group was 21% ± 5%. In contrast, no motor neurons from the cutaneous antebrachii medialis nerve of the sham group and transected nerve group were found in the spinal cord segment. These results confirmed that motor neuron regeneration occurred after cutaneous nerve end-to-side neurorrhaphy.

End-to-side neurorrhaphy repairs peripheral nerve injury: sensory nerve induces motor nerve regeneration

PubMed Central

Yu, Qing; Zhang, She-hong; Wang, Tao; Peng, Feng; Han, Dong; Gu, Yu-dong

2017-01-01

End-to-side neurorrhaphy is an option in the treatment of the long segment defects of a nerve. It involves suturing the distal stump of the disconnected nerve (recipient nerve) to the side of the intimate adjacent nerve (donor nerve). However, the motor-sensory specificity after end-to-side neurorrhaphy remains unclear. This study sought to evaluate whether cutaneous sensory nerve regeneration induces motor nerves after end-to-side neurorrhaphy. Thirty rats were randomized into three groups: (1) end-to-side neurorrhaphy using the ulnar nerve (mixed sensory and motor) as the donor nerve and the cutaneous antebrachii medialis nerve as the recipient nerve; (2) the sham group: ulnar nerve and cutaneous antebrachii medialis nerve were just exposed; and (3) the transected nerve group: cutaneous antebrachii medialis nerve was transected and the stumps were turned over and tied. At 5 months, acetylcholinesterase staining results showed that 34% ± 16% of the myelinated axons were stained in the end-to-side group, and none of the myelinated axons were stained in either the sham or transected nerve groups. Retrograde fluorescent tracing of spinal motor neurons and dorsal root ganglion showed the proportion of motor neurons from the cutaneous antebrachii medialis nerve of the end-to-side group was 21% ± 5%. In contrast, no motor neurons from the cutaneous antebrachii medialis nerve of the sham group and transected nerve group were found in the spinal cord segment. These results confirmed that motor neuron regeneration occurred after cutaneous nerve end-to-side neurorrhaphy. PMID:29171436

An Unusual Case Report of Bertolotti's Syndrome: Extraforaminal Stenosis and L5 Unilateral Root Compression (Castellvi Type III an LSTV).

PubMed

Kapetanakis, Stylianos; Chaniotakis, Constantinos; Paraskevopoulos, Constantinos; Pavlidis, Pavlos

2017-01-01

Castellvi Type III lumbosacral transitional vertebrae (LSTV) is an unusual case of Bertolotti's syndrome (BS) due to extraforaminal stenosis, especially manifesting in elderly patients. We report a case of BS in a 62 years old Greek female. The signs of the clinical examination are low back pain, sciatica, hypoesthesia, and pain to the contribution of L5 nerve. Imaging techniques revealed an LSTV Type III a (complete sacralization between LSTV and sacrum). Despite the fact that LSTV is a congenital lesion, the clinical manifestation of BS may present in the elderly population. The accumulative effect of the gradual degeneration of intervertebral foramen (stenosis) may lead to the compression of extraforaminal portion of the nerve root.

Differential diagnosis of endodontic-related inferior alveolar nerve paraesthesia with cone beam computed tomography: a case report.

PubMed

Gambarini, G; Plotino, G; Grande, N M; Testarelli, L; Prencipe, M; Messineo, D; Fratini, L; D'Ambrosio, F

2011-02-01

To discuss the use of cone-beam computed tomography (CBCT) in the differential diagnosis of a case of labiomandibular paraesthesia caused by extrusion of endodontic sealer into the mandibular canal. A 59-year-old woman suffering from a paraesthesia on the left posterior mandible and numbness on the left side of the lower lip was referred to an endodontic specialist 1 month after multiple root canal treatments. A panoramic radiograph revealed the presence of extruded root filling material beyond the apex of the mesial root of the mandibular left second molar and also beyond the apex of the first premolar. A cone beam computed tomography examination was undertaken, which confirmed the presence of radiopaque root canal filling material in the periapical area of the second molar, and revealed that the material was inside the mandibular canal. No extruded filling material was found inside the mental foramen beyond the apex of the first premolar tooth. Small field of view CBCT (where possible) can be considered an effective radiographic diagnostic device when endodontic-related inferior alveolar nerve or mental foramen paraesthesia are suspected. CBCT is able to provide detailed three-dimensional images of the tooth, the root canal system and the surrounding tissue. © 2010 International Endodontic Journal.

Changing central nervous system control following intercostal nerve transfer.

PubMed

Malessy, M J; Thomeer, R T; van Dijk, J G

1998-10-01

The goal of this study was to find which central nervous system (CNS) pathways are involved in volitional control over reinnervated biceps or pectoral muscles. Intercostal nerves (ICNs) were coapted to the musculocutaneous nerve (MCN) or the medial pectoral nerve (MPN) in 23 patients with root avulsions of the brachial plexus to restore biceps or pectoral muscle function. The facilitatory effects of respiration and voluntary contraction on cortical motor-evoked potentials of biceps or pectoral muscles were used to study CNS control over the reinnervated muscles. The time course of the facilitatory effect of respiration and voluntary contraction differed significantly. In the end stage of nerve regeneration, the facilitatory effect of voluntary contraction was significantly larger than that of respiration, indicating that the CNS control network over the muscle comes to resemble that of the recipient nerve (MCN or MPN) rather than that of the donor nerve (ICN). The strengthening of previously subthreshold synaptic connections in a CNS network connecting ICN to MCN or MPN neurons may underlie changing excitability.

Phrenic Nerve Palsy and Regional Anesthesia for Shoulder Surgery: Anatomical, Physiologic, and Clinical Considerations.

PubMed

El-Boghdadly, Kariem; Chin, Ki Jinn; Chan, Vincent W S

2017-07-01

Regional anesthesia has an established role in providing perioperative analgesia for shoulder surgery. However, phrenic nerve palsy is a significant complication that potentially limits the use of regional anesthesia, particularly in high-risk patients. The authors describe the anatomical, physiologic, and clinical principles relevant to phrenic nerve palsy in this context. They also present a comprehensive review of the strategies for reducing phrenic nerve palsy and its clinical impact while ensuring adequate analgesia for shoulder surgery. The most important of these include limiting local anesthetic dose and injection volume and performing the injection further away from the C5-C6 nerve roots. Targeting peripheral nerves supplying the shoulder, such as the suprascapular and axillary nerves, may be an effective alternative to brachial plexus blockade in selected patients. The optimal regional anesthetic approach in shoulder surgery should be tailored to individual patients based on comorbidities, type of surgery, and the principles described in this article.

Effect of magnetic attachment with stress breaker on lateral stress to abutment tooth under overdenture.

PubMed

Gonda, T; Ikebe, K; Ono, T; Nokubi, T

2004-10-01

Recently, a newly developed magnetic attachment with stress breaker was used in retentive components in overdentures. Excessive lateral stress has a more harmful effect on natural teeth than axial stress, and the magnetic attachment with stress breaker is expected to reduce lateral forces on abutment teeth and protect it teeth from excessive stress. However, the properties of this retainer have not yet been determined experimentally. This study compares the lateral forces on abutment teeth for three retainers under loading on the denture base in a model study. A mandibular simulation model is constructed to measure lateral stress. Three types of retentive devices are attached to the canine root. These devices include the conventional root coping, the conventional magnetic attachment and the new magnetic attachment with stress breaker. For each retentive device, load is generated on the occlusal table of the model overdenture, and the lateral stress on the canine root and the displacement of the overdenture measured. The magnetic attachment with stress breaker does not displace the denture and exhibits lower lateral stress in the canine root than conventional root coping and magnetic attachments.

End-to-side neurorraphy: a long-term study of neural regeneration in a rat model.

PubMed

Tarasidis, G; Watanabe, O; Mackinnon, S E; Strasberg, S R; Haughey, B H; Hunter, D A

1998-10-01

This study evaluated long-term reinnervation of an end-to-side neurorraphy and the resultant functional recovery in a rat model. The divided distal posterior tibial nerve was repaired to the side of an intact peroneal nerve. Control groups included a cut-and-repair of the posterior tibial nerve and an end-to-end repair of the peroneal nerve to the posterior tibial nerve. Evaluations included walking-track analysis, nerve conduction studies, muscle mass measurements, retrograde nerve tracing, and histologic evaluation. Walking tracks indicated poor recovery of posterior tibial nerve function in the experimental group. No significant difference in nerve conduction velocities was seen between the experimental and control groups. Gastrocnemius muscle mass measurements revealed no functional recovery in the experimental group. Similarly, retrograde nerve tracing revealed minimal motor neuron staining in the experimental group. However, some sensory staining was seen within the dorsal root ganglia of the end-to-side group. Histologic study revealed minimal myelinated axonal regeneration in the experimental group as compared with findings in the other groups. These results suggest that predominantly sensory regeneration occurs in an end-to-side neurorraphy at an end point of 6 months.

Motor root conduction block in the Lewis-Sumner syndrome.

PubMed

Lo, Yew Long; Dan, Yang-Fang; Tan, Yam-Eng; Leoh, Teng-Hee

2011-03-01

The Lewis-Sumner syndrome (LSS) is a rare immune-mediated peripheral nerve disorder presenting with asymmetric upper limb sensory complaints and motor weakness. Asian patients with LSS have not been reported in the English literature. Three Asian patients with features of LSS were prospectively studied. Our patients tended to older, female, and have involvement of the upper limbs exclusively than those in the West. They have a markedly longer disease duration before a diagnosis was made, which could also be the result of difficulty in eliciting motor root conduction block as a sign of proximal demyelination as observed in every patient. Pain is a universal feature as is sensory nerve conduction abnormality. None responded to immunotherapy, but disease stabilization was observed over the chronic course. Although rare, these unique observations in Asian patients with LSS differ from those reported in Western literature. The presence of motor root conduction block demonstrated for the first time is instrumental in establishing a diagnosis.

Soil Penetration by Earthworms and Plant Roots—Mechanical Energetics of Bioturbation of Compacted Soils

PubMed Central

2015-01-01

We quantify mechanical processes common to soil penetration by earthworms and growing plant roots, including the energetic requirements for soil plastic displacement. The basic mechanical model considers cavity expansion into a plastic wet soil involving wedging by root tips or earthworms via cone-like penetration followed by cavity expansion due to pressurized earthworm hydroskeleton or root radial growth. The mechanical stresses and resulting soil strains determine the mechanical energy required for bioturbation under different soil hydro-mechanical conditions for a realistic range of root/earthworm geometries. Modeling results suggest that higher soil water content and reduced clay content reduce the strain energy required for soil penetration. The critical earthworm or root pressure increases with increased diameter of root or earthworm, however, results are insensitive to the cone apex (shape of the tip). The invested mechanical energy per unit length increase with increasing earthworm and plant root diameters, whereas mechanical energy per unit of displaced soil volume decreases with larger diameters. The study provides a quantitative framework for estimating energy requirements for soil penetration work done by earthworms and plant roots, and delineates intrinsic and external mechanical limits for bioturbation processes. Estimated energy requirements for earthworm biopore networks are linked to consumption of soil organic matter and suggest that earthworm populations are likely to consume a significant fraction of ecosystem net primary production to sustain their subterranean activities. PMID:26087130

Summary of Full-Scale Blade Displacement Measurements of the UH- 60A Airloads Rotor

NASA Technical Reports Server (NTRS)

Abrego, Anita I.; Meyn, Larry; Burner, Alpheus W.; Barrows, Danny A.

2016-01-01

Blade displacement measurements using multi-camera photogrammetry techniques were acquired for a full-scale UH-60A rotor, tested in the National Full-Scale Aerodynamic Complex 40-Foot by 80-Foot Wind Tunnel. The measurements, acquired over the full rotor azimuth, encompass a range of test conditions that include advance ratios from 0.15 to 1.0, thrust coefficient to rotor solidity ratios from 0.01 to 0.13, and rotor shaft angles from -10.0 to 8.0 degrees. The objective was to measure the blade displacements and deformations of the four rotor blades and provide a benchmark blade displacement database to be utilized in the development and validation of rotorcraft prediction techniques. An overview of the blade displacement measurement methodology, system development, and data analysis techniques are presented. Sample results based on the final set of camera calibrations, data reduction procedures and estimated corrections that account for registration errors due to blade elasticity are shown. Differences in blade root pitch, flap and lag between the previously reported results and the current results are small. However, even small changes in estimated root flap and pitch can lead to significant differences in the blade elasticity values.

Persistent L5 lumbosacral radiculopathy caused by lumbosacral trunk schwannoma

PubMed Central

Sharifi, Guive; Jahanbakhshi, Amin

2017-01-01

Schwannomais, usually, benign tumor of nerve sheath that occurs evenly along the spinal cord. Intra-pelvic schwannoma is very rare entity that may arise from lumbosacral nerve roots or from sciatic nerve. Radicular pain of the lower limb as a presenting symptom of pelvic schwannoma is extremely rare. In the current report, the patient is presented with a right sided L5 radicular pain typical of lumbar discopathy. Interestingly, a herniated lumbar disc was noted on lumbosacral magnetic resonance imaging (MRI). In pre-operative studies a large pelvic mass was detected in the right pre-sacral area with solid and cystic components consistent with schwannoma. The patient underwent a low midline laparotomy to evacuate the retroperitoneal mass. Uniquely, we found the tumor to be arisen from lumbosacral trunk not from a root or peripheral nerve. Most cases with intra-pelvic schwannoma present so late with vague abdominal and pelvic discomfort or pain, low back pain, urinary and bowel symptoms because of compressive effect of the tumor, or incidentally following gynecologic work-ups; So, these patients are mostly referred to gynecologists and urologists. A neurosurgeon should have a high degree of suspicion to diagnose such an entity among his or her patients presented with pains typical for discopathy. PMID:28413533

Calpain-2 Regulates TNF-α Expression Associated with Neuropathic Pain Following Motor Nerve Injury.

PubMed

Chen, Shao-Xia; Liao, Guang-Jie; Yao, Pei-Wen; Wang, Shao-Kun; Li, Yong-Yong; Zeng, Wei-An; Liu, Xian-Guo; Zang, Ying

2018-04-15

Both calpain-2 (CALP2) and tumor necrosis factor-α (TNF-α) contribute to persistent bilateral hypersensitivity in animals subjected to L5 ventral root transection (L5-VRT), a model of selective motor fiber injury without sensory nerve damage. However, specific upstream mechanisms regulating TNF-α overexpression and possible relationships linking CALP2 and TNF-α have not yet been investigated in this model. We examined changes in CALP2 and TNF-α protein levels and alterations in bilateral mechanical threshold within 24 h following L5-VRT model injury. We observed robust elevation of CALP2 and TNF-α in bilateral dorsal root ganglias (DRGs) and bilateral spinal cord neurons. CALP2 and TNF-α protein induction by L5-VRT were significantly inhibited by pretreatment using the calpain inhibitor MDL28170. Administration of CALP2 to rats without nerve injury further supported a role of CALP2 in the regulation of TNF-α expression. Although clinical trials of calpain inhibition therapy for alleviation of neuropathic pain induced by motor nerve injury have not yet shown success, our observations linking CALP2 and TNF-α provide a framework of a systems' approach based perspective for treating neuropathic pain. Copyright © 2018 IBRO. Published by Elsevier Ltd. All rights reserved.

Does a paresthesia during spinal needle insertion indicate intrathecal needle placement?

PubMed

Pong, Ryan P; Gmelch, Benjamin S; Bernards, Christopher M

2009-01-01

Paresthesias are relatively common during spinal needle insertion, however, the clinical significance of the paresthesia is unknown. A paresthesia may result from needle-to-nerve contact with a spinal nerve in the epidural space, or, with far lateral needle placement, may result from contact with a spinal nerve within the intervertebral foramen. However, it is also possible and perhaps more likely, that paresthesias occur when the spinal needle contacts a spinal nerve root within the subarachnoid space. This study was designed to test this latter hypothesis. Patients (n = 104) scheduled for surgery under spinal anesthesia were observed during spinal needle insertion. If a paresthesia occurred, the needle was fixed in place and the stylet removed to observe whether cerebrospinal fluid (CSF) flowed from the hub. The presence of CSF was considered proof that the needle had entered the subarachnoid space. Paresthesias occurred in 14/103 (13.6%) of patients; 1 patient experienced a paresthesia twice. All paresthesias were transient. Following a paresthesia, CSF was observed in the needle hub 86.7% (13/15) of the time. Our data suggest that the majority of transient paresthesias occur when the spinal needle enters the subarachnoid space and contacts a spinal nerve root. Therefore, when transient paresthesias occur during spinal needle placement it is appropriate to stop and assess for the presence of CSF in the needle hub, rather than withdraw and redirect the spinal needle away from the side of the paresthesia as some authors have suggested.

ATG5 overexpression is neuroprotective and attenuates cytoskeletal and vesicle-trafficking alterations in axotomized motoneurons.

PubMed

Leiva-Rodríguez, Tatiana; Romeo-Guitart, David; Marmolejo-Martínez-Artesero, Sara; Herrando-Grabulosa, Mireia; Bosch, Assumpció; Forés, Joaquim; Casas, Caty

2018-05-24

Injured neurons should engage endogenous mechanisms of self-protection to limit neurodegeneration. Enhancing efficacy of these mechanisms or correcting dysfunctional pathways may be a successful strategy for inducing neuroprotection. Spinal motoneurons retrogradely degenerate after proximal axotomy due to mechanical detachment (avulsion) of the nerve roots, and this limits recovery of nervous system function in patients after this type of trauma. In a previously reported proteomic analysis, we demonstrated that autophagy is a key endogenous mechanism that may allow motoneuron survival and regeneration after distal axotomy and suture of the nerve. Herein, we show that autophagy flux is dysfunctional or blocked in degenerated motoneurons after root avulsion. We also found that there were abnormalities in anterograde/retrograde motor proteins, key secretory pathway factors, and lysosome function. Further, LAMP1 protein was missorted and underglycosylated as well as the proton pump v-ATPase. In vitro modeling revealed how sequential disruptions in these systems likely lead to neurodegeneration. In vivo, we observed that cytoskeletal alterations, induced by a single injection of nocodazole, were sufficient to promote neurodegeneration of avulsed motoneurons. Besides, only pre-treatment with rapamycin, but not post-treatment, neuroprotected after nerve root avulsion. In agreement, overexpressing ATG5 in injured motoneurons led to neuroprotection and attenuation of cytoskeletal and trafficking-related abnormalities. These discoveries serve as proof of concept for autophagy-target therapy to halting the progression of neurodegenerative processes.

Is endodontic treatment necessary during coronectomy procedure?

PubMed

Sencimen, Metin; Ortakoglu, Kerim; Aydin, Cumhur; Aydintug, Yavuz S; Ozyigit, Aykut; Ozen, Tuncer; Gunaydin, Yilmaz

2010-10-01

Close proximity of the inferior alveolar nerve (IAN) to the third molar roots can result in nerve injuries during extraction of third molars. Consequently, it is necessary to determine the relationship of the nerve and roots to avoid damage to the IAN. Computed tomography scans are widely used to determine the correct relationship between the IAN and lower third molars. The study consisted of 10 patients with 16 lower third molars in close relationship with the IAN who were divided into a study group and a control group. The patients in the study group were treated via coronectomies performed with endodontic treatments. The patients in the control group underwent coronectomies without endodontic treatment. The patients were followed up for at least 1 year. We had to extract 7 of the roots because of the infection in 8 patients belonging to the study group, which were treated endodontically. Moreover, there were 3 cases of IAN damage because of the extraction in the study group. However, in the control group, no infection was determined and IAN damage was absent. Coronectomy appears to be a reliable technique to protect the IAN from damage. This procedure has a low incidence of complications. Endodontic treatment does not affect the success of this method according to our results. Copyright © 2010 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Displacement of a Broken Dental Injection Needle Into the Perivertebral Space.

PubMed

Sahin, Bayram; Yildirimturk, Senem; Sirin, Yigit; Basaran, Bora

2017-07-01

Dental injection needle breakage is an uncommon problem in dental practice. Displacement of the broken fragment into anatomical spaces is, on the other hand, a serious complication that occurs most commonly during inferior alveolar nerve blocks as a result of material wear, incorrect application of the anesthesia technique, or sudden movement of the patient during injection. Further complications such as infection, trismus, and nerve paralysis may exacerbate the condition and, if not treated adequately, life-threatening conditions may develop over time as the fragment dislodges deeper in soft tissues. Clinical symptoms of the patient, as well as the findings gathered from detailed physical examination and radiographic evaluation, are important factors to consider before performing an exploratory surgery. Removal of a broken needle may be troublesome due to its proximity to vital anatomic structures. Multislice computed tomography is a reliable imaging modality that provides accurate information to pinpoint the exact location of the needle fragment.This report describes a case of needle breakage occurred during inferior alveolar nerve block which was performed to extract a third molar tooth and the migration of the broken fragment from the right mandibular ramus area into the perivertebral space, with special emphasis on the surgical retrieval technique with multiplanar computed tomography imaging guidance.

Phrenic and intercostal nerves with rhythmic discharge can promote early nerve regeneration after brachial plexus repair in rats.

PubMed

Rui, Jing; Xu, Ya-Li; Zhao, Xin; Li, Ji-Feng; Gu, Yu-Dong; Lao, Jie

2018-05-01

Exogenous discharge can positively promote nerve repair. We, therefore, hypothesized that endogenous discharges may have similar effects. The phrenic nerve and intercostal nerve, controlled by the respiratory center, can emit regular nerve impulses; therefore these endogenous automatically discharging nerves might promote nerve regeneration. Action potential discharge patterns were examined in the diaphragm, external intercostal and latissimus dorsi muscles of rats. The phrenic and intercostal nerves showed rhythmic clusters of discharge, which were consistent with breathing frequency. From the first to the third intercostal nerves, spontaneous discharge amplitude was gradually increased. There was no obvious rhythmic discharge in the thoracodorsal nerve. Four animal groups were performed in rats as the musculocutaneous nerve cut and repaired was bland control. The other three groups were followed by a side-to-side anastomosis with the phrenic nerve, intercostal nerve and thoracodorsal nerve. Compound muscle action potentials in the biceps muscle innervated by the musculocutaneous nerve were recorded with electrodes. The tetanic forces of ipsilateral and contralateral biceps muscles were detected by a force displacement transducer. Wet muscle weight recovery rate was measured and pathological changes were observed using hematoxylin-eosin staining. The number of nerve fibers was observed using toluidine blue staining and changes in nerve ultrastructure were observed using transmission electron microscopy. The compound muscle action potential amplitude was significantly higher at 1 month after surgery in phrenic and intercostal nerve groups compared with the thoracodorsal nerve and blank control groups. The recovery rate of tetanic tension and wet weight of the right biceps were significantly lower at 2 months after surgery in the phrenic nerve, intercostal nerve, and thoracodorsal nerve groups compared with the negative control group. The number of myelinated axons distal to the coaptation site of the musculocutaneous nerve at 1 month after surgery was significantly higher in phrenic and intercostal nerve groups than in thoracodorsal nerve and negative control groups. These results indicate that endogenous autonomic discharge from phrenic and intercostal nerves can promote nerve regeneration in early stages after brachial plexus injury.

Allotransplanted DRG neurons or Schwann cells affect functional recovery in a rodent model of sciatic nerve injury.

PubMed

Dayawansa, Samantha; Wang, Ernest W; Liu, Weimin; Markman, John D; Gelbard, Harris A; Huang, Jason H

2014-11-01

In this study, the functional recoveries of Sprague-Dawley rats following repair of a complete sciatic nerve transection using allotransplanted dorsal root ganglion (DRG) neurons or Schwann cells were examined using a number of outcome measures. Four groups were compared: (1) repair with a nerve guide conduit seeded with allotransplanted Schwann cells harvested from Wistar rats, (2) repair with a nerve guide conduit seeded with DRG neurons, (3) repair with solely a nerve guide conduit, and (4) sham-surgery animals where the sciatic nerve was left intact. The results corroborated our previous reported histology findings and measures of immunogenicity. The Wistar-DRG-treated group achieved the best recovery, significantly outperforming both the Wistar-Schwann group and the nerve guide conduit group in the Von Frey assay of touch response (P < 0.05). Additionally, Wistar-DRG and Wistar-Schwann seeded repairs showed lower frequency and severity in an autotomy measure of the self-mutilation of the injured leg because of neuralgia. These results suggest that in complete peripheral nerve transections, surgical repair using nerve guide conduits with allotransplanted DRG and Schwann cells may improve recovery, especially DRG neurons, which elicit less of an immune response.

The role of suture cutout in the failure of meniscal root repair during the early post-operative period: a biomechanical study.

PubMed

Perez-Blanca, Ana; Prado Nóvoa, María; Lombardo Torre, Maximiano; Espejo-Reina, Alejandro; Ezquerro Juanco, Francisco; Espejo-Baena, Alejandro

2018-04-01

To assess the role of suture cutout in the mechanics of failure of the repaired posterior meniscal root during the early post-operative period when using sutures of different shape. Twenty medial porcine menisci were randomized in two groups depending on the suture shape used to repair the posterior root: thread or tape. The sutured menisci were subjected to cyclic loading (1000 cycles, (10, 30) N) followed by load-to-failure testing. Residual displacements, stiffness, and ultimate failure load were determined. During tests, the tissue-suture interface was recorded using a high-resolution camera. In cyclic tests, cutout progression at the suture insertion points was not observed for any specimen of either group and no differences in residual displacements were found between use of thread or tape. In load-to-failure tests, suture cutout started in all menisci at a load close to the ultimate failure and all specimens failed by suture pullout. Suture tape had a greater ultimate load with no other differences. In a porcine model of a repaired posterior meniscal root subjected to cyclic loads representative of current rehabilitation protocols in the early post-operative period under restricted loading conditions, suture cutout was not found as a main source of permanent root displacement when using suture thread or tape. Suture cutout progression started at high loading levels close to the ultimate load of the construct. Tape, with a meniscus-suture contact area larger than thread, produced higher ultimate load.

F wave index: A diagnostic tool for peripheral neuropathy.

PubMed

Sathya, G R; Krishnamurthy, N; Veliath, Susheela; Arulneyam, Jayanthi; Venkatachalam, J

2017-03-01

Each skeletal muscle is usually supplied by two or more nerve roots and if one nerve root is affected and the other is spared, the clinically used F wave minimum latency can still be normal. An F wave index was constructed taking into consideration the other parameters of the F wave such as persistence, chronodispersion, latency, arm-length to determine its usefulness in the diagnosis of peripheral neuropathy. This study was undertaken to construct the F wave index in the upper limb for the median nerve in normal healthy adult males and in patients with peripheral neuropathy and to compare the values obtained in both groups. This hospital-based study was carried out on 40 males who were diagnosed to have peripheral neuropathy and on 40 age matched healthy males who served as the control group. The F wave recording was done using a digitalized nerve conduction/electromyography/EP machine in a quiet and dimly lit room. All recordings were done between 0900 and 1100 h at an ambient temperature of 22°C. The F wave recording was obtained from a fully relaxed muscle by stimulating the median nerve. The median value for F wave index obtained from median nerve (abductor pollicis brevis) in patients with peripheral neuropathy [right arm - 35.85, interquartile range (IQR) - 35.26; left arm - 39.49, IQR - 39.49] was significantly lower (P=0.001) as compared to the control group (right arm - 102.62, IQR - 83.76; left arm - 77.43, IQR - 58.02). Our results showed that F wave index in upper limb was significantly lower in patients with peripheral neuropathy than the healthy controls, and could be used for early detection of peripheral neuropathy.

Cervical Spondylosis

MedlinePlus

... not. Smoking. Smoking has been linked to increased neck pain. Complications If your spinal cord or nerve roots become severely compressed as a result of cervical spondylosis, the damage can be permanent. By Mayo ...

An Unusual Case Report of Bertolotti’s Syndrome: Extraforaminal Stenosis and L5 Unilateral Root Compression (Castellvi Type III an LSTV)

PubMed Central

Kapetanakis, Stylianos; Chaniotakis, Constantinos; Paraskevopoulos, Constantinos; Pavlidis, Pavlos

2017-01-01

Introduction: Castellvi Type III lumbosacral transitional vertebrae (LSTV) is an unusual case of Bertolotti’s syndrome (BS) due to extraforaminal stenosis, especially manifesting in elderly patients. Case Report: We report a case of BS in a 62 years old Greek female. The signs of the clinical examination are low back pain, sciatica, hypoesthesia, and pain to the contribution of L5 nerve. Imaging techniques revealed an LSTV Type III a (complete sacralization between LSTV and sacrum). Conclusion: Despite the fact that LSTV is a congenital lesion, the clinical manifestation of BS may present in the elderly population. The accumulative effect of the gradual degeneration of intervertebral foramen (stenosis) may lead to the compression of extraforaminal portion of the nerve root. PMID:29051870

Reappraising entrapment neuropathies--mechanisms, diagnosis and management.

PubMed

Schmid, Annina B; Nee, Robert J; Coppieters, Michel W

2013-12-01

The diagnosis of entrapment neuropathies can be difficult because symptoms and signs often do not follow textbook descriptions and vary significantly between patients with the same diagnosis. Signs and symptoms which spread outside of the innervation territory of the affected nerve or nerve root are common. This Masterclass provides insight into relevant mechanisms that may account for this extraterritorial spread in patients with entrapment neuropathies, with an emphasis on neuroinflammation at the level of the dorsal root ganglia and spinal cord, as well as changes in subcortical and cortical regions. Furthermore, we describe how clinical tests and technical investigations may identify these mechanisms if interpreted in the context of gain or loss of function. The management of neuropathies also remains challenging. Common treatment strategies such as joint mobilisation, neurodynamic exercises, education, and medications are discussed in terms of their potential to influence certain mechanisms at the site of nerve injury or in the central nervous system. The mechanism-oriented approach for this Masterclass seems warranted given the limitations in the current evidence for the diagnosis and management of entrapment neuropathies. Copyright © 2013 Elsevier Ltd. All rights reserved.

The comparative performance of Roots type aircraft engine superchargers as affected by change in impeller speed and displacement

NASA Technical Reports Server (NTRS)

Ware, Marsden; Wilson, Ernest E

1929-01-01

This report presents the results of tests made on three sizes of roots type aircraft engine superchargers. The impeller contours and diameters of these machines were the same, but the length were 11, 8 1/4, and 4 inches, giving displacements of 0.509, 0.382, and 0.185 cubic foot per impeller revolution. The information obtained serves as a basis for the examination of the individual effects of impeller speed and displacement on performance and of the comparative performance when speed and displacement are altered simultaneously to meet definite service requirements. According to simple theory, when assuming no losses, the air weight handled and the power required for a given pressure difference are directly proportional to the speed and the displacement. These simple relations are altered considerably by the losses. When comparing the performance of different sizes of machines whose impeller speeds are so related that the same service requirements are met, it is found that the individual effects of speed and displacement are canceled to a large extent, and the only considerable difference is the difference in the power losses which decrease with increase in the displacement and the accompanying decrease in speed. This difference is small in relation to the net power of the engine supercharger unit, so that a supercharger with short impellers may be used in those applications where the space available is very limited with any considerable sacrifice in performance.

Concepts of nerve regeneration and repair applied to brachial plexus reconstruction.

PubMed

Bertelli, Jayme Augusto; Ghizoni, Marcos Flávio

2006-01-01

Brachial plexus injury is a serious condition that usually affects young adults. Progress in brachial plexus repair is intimately related to peripheral nerve surgery, and depends on clinical and experimental studies. We review the rat brachial plexus as an experimental model, together with its behavioral evaluation. Techniques to repair nerves, such as neurolysis, nerve coaptation, nerve grafting, nerve transfer, fascicular transfer, direct muscle neurotization, and end-to-side neurorraphy, are discussed in light of the authors' experimental studies. Intradural repair of the brachial plexus by graft implants into the spinal cord and motor rootlet transfer offer new possibilities in brachial plexus reconstruction. The clinical experience of intradural repair is presented. Surgical planning in root rupture or avulsion is proposed. In total avulsion, the authors are in favor of the reconstruction of thoraco-brachial and abdomino-antebrachial grasping, and on the transfer of the brachialis muscle to the wrist extensors if it is reinnervated. Surgical treatment of painful conditions and new drugs are also discussed.

Use of GDNF-Releasing Nanofiber Nerve Guide Conduits for the Repair of Conus medullaris/Cauda Equina Injury in the Non-Human Primate

DTIC Science & Technology

2011-10-01

Cauda equina, non-human primate, ventral root. neural repair, electromyography , magnetic resonance imaging 16. SECURITY CLASSIFICATION OF: 17...of a guidance channel without GDNF release and a peripheral nerve graft to bridge the tissue gap. A comprehensive set of electrodiagnostic, imaging ... Electromyography (EMG) recordings of the external anal sphincter are obtained pre-operatively as baseline records. The external anal sphincter muscle

Dose postural control improve following application of transcutaneous electrical nerve stimulation in diabetic peripheral neuropathic patients? A randomized placebo control trial.

PubMed

Saadat, Z; Rojhani-Shirazi, Z; Abbasi, L

2017-12-01

peripheral neuropathy is the most common problem of diabetes. Neuropathy leads to lower extremity somatosensory deficits and postural instability in these patients. However, there are not sufficient evidences for improving postural control in these patients. To investigate the effects of transcutaneous electrical nerve stimulation (TENS) on postural control in patients with diabetic neuropathy. Twenty eighth patients with diabetic neuropathy (40-55 Y/O) participated in this RCT study. Fourteen patients in case group received TENS and sham TENS was used for control group. Force plate platform was used to extract sway velocity and COP displacement parameters for postural control evaluation. The mean sway velocity and center of pressure displacement along the mediolateral and anteroposterior axes were not significantly different between two groups after TENS application (p>0.05). Application of 5min high frequency TENS on the knee joint could not improve postural control in patients with diabetic neuropathy. Copyright © 2017. Published by Elsevier Ltd.

Optic nerve compression as a late complication of a hydrogel explant with silicone encircling band.

PubMed

Crama, Niels; Kluijtmans, Leo; Klevering, B Jeroen

2018-06-01

To present a complication of compressive optic neuropathy caused by a swollen hydrogel explant and posteriorly displaced silicone encircling band. A 72-year-old female patient presented with progressive visual loss and a tilted optic disc. Her medical history included a retinal detachment in 1993 that was treated with a hydrogel explant under a solid silicone encircling band. Visual acuity had decreased from 6/10 to 6/20 and perimetry showed a scotoma in the temporal superior quadrant. On Magnetic Resonance Imaging (MRI), compression of the optic nerve by a displaced silicone encircling band inferior nasally in combination with a swollen episcleral hydrogel explant was observed. Surgical removal of the hydrogel explant and silicone encircling band was uneventful and resulted in improvement of visual acuity and visual field loss. This is the first report on compressive optic neuropathy caused by swelling of a hydrogel explant resulting in a dislocated silicone encircling band. The loss of visual function resolved upon removal of the explant and encircling band.

A novel platform for in vitro analysis of torque, forces, and three-dimensional file displacements during root canal preparations: application to ProTaper rotary files.

PubMed

Diop, Amadou; Maurel, Nathalie; Oiknine, Michel; Patoor, Etienne; Machtou, Pierre

2009-04-01

We proposed a new testing setup and in vitro experimental procedure allowing the analysis of the forces, torque, and file displacements during the preparation of root canals using nickel-titanium rotary endodontic files. We applied it to the preparation of 20 fresh frozen cadaveric teeth using ProTaper files (Dentsply Maillefer, Ballaigues, Switzerland), according to a clinically used sequence. During the preparations, a clinical hand motion was performed by an endodontist, and we measured the applied torque around the file axis and also the involved three-dimensional forces and 3-dimensional file displacements. Such a biomechanical procedure is useful to better understand the working conditions of the files in terms of loads and displacements. It could be used to analyze the effects of various mechanical and geometric parameters on the files' behavior and to get data for modelling purposes. Finally, it could contribute to studies aiming to improve files design in order to reduce the risks of file fractures.

Opening and closing characteristics of the aortic valve after valve-sparing procedures using a new aortic root conduit.

PubMed

De Paulis, R; De Matteis, G M; Nardi, P; Scaffa, R; Buratta, M M; Chiariello, L

2001-08-01

The durability of aortic valve-sparing procedures is negatively affected by increased leaflet stress in the absence of normally shaped sinuses of Valsalva. We compared valve motion after remodeling procedures using a standard conduit and a specifically designed aortic root conduit. Echocardiographic studies of the aortic valve dynamics were performed in 14 patients after remodeling of the aortic root (7 standard conduits, group A; 7 new conduits, group B) and in 7 controls (group C). Opening and closing leaflet velocities and percent of slow closing leaflet displacement were measured. Root distensibility and the pressure strain of the elastic modulus were measured at all root levels. Root distensibility and the pressure strain of the elastic modulus were different in group A and B only at the sinuses (p < 0.001). Opening and closing leaflet velocities were not different among groups. Slow closing leaflet displacement was markedly more evident in group B patients (24.2%+/-1.9% versus 2.5%+/-1.9% in group A, p < 0.001) and similar to controls (22.1%+/-7.9%). The new conduit guarantees dynamic features of the aortic valve leaflets superior to those obtained with standard conduits and more similar to normal subjects.

The Reliability of Panoramic Radiography Versus Cone Beam Computed Tomography when Evaluating the Distance to the Alveolar Nerve in the Site of Lateral Teeth.

PubMed

Česaitienė, Gabrielė; Česaitis, Kęstutis; Junevičius, Jonas; Venskutonis, Tadas

2017-07-04

BACKGROUND The aim of this study was to compare the reliability of panoramic radiography (PR) and cone beam computed tomography (CBCT) in the evaluation of the distance of the roots of lateral teeth to the inferior alveolar nerve canal (IANC). MATERIAL AND METHODS 100 PR and 100 CBCT images that met the selection criteria were selected from the database. In PR images, the distances were measured using an electronic caliper with 0.01 mm accuracy and white light x-ray film reviewer. Actual values of the measurements were calculated taking into consideration the magnification used in PR images (130%). Measurements on CBCT images were performed using i-CAT Vision software. Statistical data analysis was performed using R software and applying Welch's t-test and the Wilcoxon test. RESULTS There was no statistically significant difference in the mean distance from the root of the second premolar and the mesial and distal roots of the first molar to the IANC between PR and CBCT images. The difference in the mean distance from the mesial and distal roots of the second and the third molars to the IANC measured in PR and CBCT images was statistically significant. CONCLUSIONS PR may be uninformative or misleading when measuring the distance from the mesial and distal roots of the second and the third molars to the IANC.

The Reliability of Panoramic Radiography Versus Cone Beam Computed Tomography when Evaluating the Distance to the Alveolar Nerve in the Site of Lateral Teeth

PubMed Central

Česaitienė, Gabrielė; Česaitis, Kęstutis; Junevičius, Jonas; Venskutonis, Tadas

2017-01-01

Background The aim of this study was to compare the reliability of panoramic radiography (PR) and cone beam computed tomography (CBCT) in the evaluation of the distance of the roots of lateral teeth to the inferior alveolar nerve canal (IANC). Material/Methods 100 PR and 100 CBCT images that met the selection criteria were selected from the database. In PR images, the distances were measured using an electronic caliper with 0.01 mm accuracy and white light x-ray film reviewer. Actual values of the measurements were calculated taking into consideration the magnification used in PR images (130%). Measurements on CBCT images were performed using i-CAT Vision software. Statistical data analysis was performed using R software and applying Welch’s t-test and the Wilcoxon test. Results There was no statistically significant difference in the mean distance from the root of the second premolar and the mesial and distal roots of the first molar to the IANC between PR and CBCT images. The difference in the mean distance from the mesial and distal roots of the second and the third molars to the IANC measured in PR and CBCT images was statistically significant. Conclusions PR may be uninformative or misleading when measuring the distance from the mesial and distal roots of the second and the third molars to the IANC. PMID:28674379

Reliability of gadolinium-enhanced magnetic resonance imaging findings and their correlation with clinical outcome in patients with sciatica.

PubMed

el Barzouhi, Abdelilah; Vleggeert-Lankamp, Carmen L A M; Lycklama à Nijeholt, Geert J; Van der Kallen, Bas F; van den Hout, Wilbert B; Koes, Bart W; Peul, Wilco C

2014-11-01

Gadolinium-enhanced magnetic resonance imaging (Gd-MRI) is often performed in the evaluation of patients with persistent sciatica after lumbar disc surgery. However, correlation between enhancement and clinical findings is debated, and limited data are available regarding the reliability of enhancement findings. To evaluate the reliability of Gd-MRI findings and their correlation with clinical findings in patients with sciatica. Prospective observational evaluation of patients who were enrolled in a randomized trial with 1-year follow-up. Patients with 6- to 12-week sciatica, who participated in a multicentre randomized clinical trial comparing an early surgery strategy with prolonged conservative care with surgery if needed. In total 204 patients underwent Gd-MRI at baseline and after 1 year. Patients were assessed by means of the Roland Disability Questionnaire (RDQ) for sciatica, visual analog scale (VAS) for leg pain, and patient-reported perceived recovery at 1 year. Kappa coefficients were used to assess interobserver reliability. In total, 204 patients underwent Gd-MRI at baseline and after 1 year. Magnetic resonance imaging findings were correlated to the outcome measures using the Mann-Whitney U test for continuous data and Fisher exact tests for categorical data. Poor-to-moderate agreement was observed regarding Gd enhancement of the herniated disc and compressed nerve root (kappa<0.41), which was in contrast with excellent interobserver agreement of the disc level of the herniated disc and compressed nerve root (kappa>0.95). Of the 59 patients with an enhancing herniated disc at 1 year, 86% reported recovery compared with 100% of the 12 patients with nonenhancing herniated discs (p=.34). Of the 12 patients with enhancement of the most affected nerve root at 1 year, 83% reported recovery compared with 85% of the 192 patients with no enhancement (p=.69). Patients with and without enhancing herniated discs or nerve roots at 1 year reported comparable outcomes on RDQ and VAS-leg pain. Reliability of Gd-MRI findings was poor-to-moderate and no correlation was observed between enhancement and clinical findings at 1-year follow-up. Copyright © 2014 Elsevier Inc. All rights reserved.

The sensory-motor bridge neurorraphy: an anatomic study of feasibility between sensory branch of the musculocutaneous nerve and deep branch of the radial nerve.

PubMed

Goubier, Jean-Noel; Teboul, Frédéric

2011-05-01

Restoring elbow flexion remains the first step in the management of total palsy of the brachial plexus. Non avulsed upper roots may be grafted on the musculocutaneous nerve. When this nerve is entirely grafted, some motor fibres regenerate within the sensory fibres quota. Aiming potential utilization of these lost motor fibres, we attempted suturing the sensory branch of the musculocutaneous nerve onto the deep branch of the radial nerve. The objective of our study was to assess the anatomic feasibility of such direct suturing of the terminal sensory branch of the musculocutaneous nerve onto the deep branch of the radial nerve. The study was carried out with 10 upper limbs from fresh cadavers. The sensory branch of the musculocutaneous muscle was dissected right to its division. The motor branch of the radial nerve was identified and dissected as proximally as possible into the radial nerve. Then, the distance separating the two nerves was measured so as to assess whether direct neurorraphy of the two branches was feasible. The excessive distance between the two branches averaged 6 mm (1-13 mm). Thus, direct neurorraphy of the sensory branch of the musculocutaneous nerve and the deep branch of the radial nerve was possible. When the whole musculocutaneous nerve is grafted, some of its motor fibres are lost amongst the sensory fibres (cutaneous lateral antebrachial nerve). By suturing this sensory branch onto the deep branch of the radial nerve, "lost" fibres may be retrieved, resulting in restoration of digital extension. Copyright © 2011 Wiley-Liss, Inc.

Neurotization of elements of the brachial plexus.

PubMed

Friedman, A H

1991-01-01

Satisfactory therapy for an avulsion injury of the brachial plexus has yet to be described. Dorsal root entry zone lesions will usually mitigate the searing pain which is so disabling in some of these patients. Neurotization procedures are effective in restoring limited function to these patients. The most useful isolated movement of the upper extremity is elbow flexion, which is thus the primary target of neurotization procedures. Intercostal nerves and elements of the cervical plexus are the most commonly used donor nerves for neurotization procedures. From our experience and from a review of the literature, it appears that these procedures will be successful in approximately 50% of cases. It must be stressed that before performing a nerve transfer, the surgeon must be certain that the patient is not a candidate for a simple nerve graft.

Cellular and molecular mechanisms of tooth root development

PubMed Central

Li, Jingyuan; Parada, Carolina

2017-01-01

ABSTRACT The tooth root is an integral, functionally important part of our dentition. The formation of a functional root depends on epithelial-mesenchymal interactions and integration of the root with the jaw bone, blood supply and nerve innervations. The root development process therefore offers an attractive model for investigating organogenesis. Understanding how roots develop and how they can be bioengineered is also of great interest in the field of regenerative medicine. Here, we discuss recent advances in understanding the cellular and molecular mechanisms underlying tooth root formation. We review the function of cellular structure and components such as Hertwig's epithelial root sheath, cranial neural crest cells and stem cells residing in developing and adult teeth. We also highlight how complex signaling networks together with multiple transcription factors mediate tissue-tissue interactions that guide root development. Finally, we discuss the possible role of stem cells in establishing the crown-to-root transition, and provide an overview of root malformations and diseases in humans. PMID:28143844

Endogenous neurotrophin-3 promotes neuronal sprouting from dorsal root ganglia.

PubMed

Wang, Xu-Yang; Gu, Pei-Yuan; Chen, Shi-Wen; Gao, Wen-Wei; Tian, Heng-Li; Lu, Xiang-He; Zheng, Wei-Ming; Zhuge, Qi-Chuan; Hu, Wei-Xing

2015-11-01

In the present study, we investigated the role of endogenous neurotrophin-3 in nerve terminal sprouting 2 months after spinal cord dorsal root rhizotomy. The left L1-5 and L7-S2 dorsal root ganglia in adult cats were exposed and removed, preserving the L6 dorsal root ganglia. Neurotrophin-3 was mainly expressed in large neurons in the dorsal root ganglia and in some neurons in spinal lamina II. Two months after rhizotomy, the number of neurotrophin-3-positive neurons in the spared dorsal root ganglia and the density of neurite sprouts emerging from these ganglia were increased. Intraperitoneal injection of an antibody against neurotrophin-3 decreased the density of neurite sprouts. These findings suggest that endogenous neurotrophin-3 is involved in spinal cord plasticity and regeneration, and that it promotes axonal sprouting from the dorsal root ganglia after spinal cord dorsal root rhizotomy.

Expression patterns and role of PTEN in rat peripheral nerve development and injury.

PubMed

Chen, Hui; Xiang, Jianping; Wu, Junxia; He, Bo; Lin, Tao; Zhu, Qingtang; Liu, Xiaolin; Zheng, Canbin

2018-05-29

Studies have suggested that phosphatase and tensin homolog (PTEN) plays an important role in neuroprotection and neuronal regeneration. To better understand the potential role of PTEN with respect to peripheral nerve development and injury, we investigated the expression pattern of PTEN at different stages of rat peripheral nerve development and injury and subsequently assessed the effect of pharmacological inhibition of PTEN using bpV(pic) on axonal regeneration in a rat sciatic nerve crush injury model. During the early stages of development, PTEN exhibits low expression in neuronal cell bodies and axons. From embryonic day (E) 18.5 and postnatal day (P)5 to adult, PTEN protein becomes more detectable, with high expression in the dorsal root ganglia (DRG) and axons. PTEN expression is inhibited in peripheral nerves, preceding myelination during neuronal development and remyelination after acute nerve injury. Low PTEN expression after nerve injury promotes Akt/mammalian target of rapamycin (mTOR) signaling pathway activity. In vivo pharmacological inhibition of PTEN using bpV(pic) promoted axonal regrowth, increased the number of myelinated nerve fibers, improved locomotive recovery and enhanced the amplitude response and nerve conduction velocity following stimulation in a rat sciatic nerve crush injury model. Thus, we suggest that PTEN may play potential roles in peripheral nerve development and regeneration and that inhibition of PTEN expression is beneficial for nerve regeneration and functional recovery after peripheral nerve injury. Copyright © 2018 Elsevier B.V. All rights reserved.

[Synthesis and evaluation of a novel injectable and water-swelling gingival displacement materials].

PubMed

Xu, Xiaohua; Zhu, Xiaopeng; Ning, Tianyun; Liu, Wei; Li, Quanli

2012-04-01

To synthesize and evaluate a novel injectable and water-swelling gingival displacement materials. A kind of water-swelling polymer, kaolin and aluminum chloride were mechanically mixed at certain ratio in water solution, resulting to a novel paste materials for gingival displacement. Then, its stability in aqueous solution and water swelling properties were evaluated in vitro. The effect on gingival displacement was evaluated by animal experiments in dogs. A commercial gingival displacement materials paste of Expasyl was used as control. While contacting with water, the novel gingival displacement paste did not collapse, maintained its integrity structure, and could expand for adsorbing water. Animal experiments in dogs showed that the materials could lead to displace the gingival margins from the dental root surfaces. The novel injectable and expanded gingival displacement material is efficient to retract free gingival margin with potential clinical application.

Swimming Training Reduces Neuroma Pain by Regulating Neurotrophins

PubMed Central

TIAN, JINGE; YU, TINGTING; XU, YONGMING; PU, SHAOFENG; LV, YINGYING; ZHANG, XIN; DU, DONGPING

2018-01-01

ABSTRACT Introduction Neuroma formation after peripheral nerve transection leads to severe neuropathic pain in amputees. Previous studies suggested that physical exercise could bring beneficial effect on alleviating neuropathic pain. However, the effect of exercise on neuroma pain still remained unclear. In addition, long-term exercise can affect the expression of neurotrophins (NT), such as nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF), which play key roles in nociceptor sensitization and nerve sprouting after nerve injury. Here, we investigated whether long-term swimming exercise could relieve neuroma pain by modulating NT expression. Methods We used a tibial neuroma transposition (TNT) rat model to mimic neuroma pain. After TNT surgery, rats performed swimming exercise for 5 wk. Neuroma pain and tactile sensitivities were detected using von Frey filaments. Immunofluorescence was applied to analyze neuroma formation. NGF and BDNF expressions in peripheral neuroma, dorsal root ganglion, and the spinal cord were measured using enzyme-linked immunosorbent assay and Western blotting. Results TNT led to neuroma formation, induced neuroma pain, and mechanical allodynia in hind paw. Five-week swimming exercise inhibited neuroma formation and relieved mechanical allodynia in the hind paw and neuroma pain in the lateral ankle. The analgesic effect lasted for at least 1 wk, even when the exercise ceased. TNT elevated the expressions of BDNF and NGF in peripheral neuroma, dorsal root ganglion, and the spinal cord to different extents. Swimming also decreased the elevation of NT expression. Conclusions Swimming exercise not only inhibits neuroma formation induced by nerve transection but also relieves pain behavior. These effects might be associated with the modulation of NT. PMID:28846565

Swimming Training Reduces Neuroma Pain by Regulating Neurotrophins.

PubMed

Tian, Jinge; Yu, Tingting; Xu, Yongming; Pu, Shaofeng; Lv, Yingying; Zhang, Xin; DU, Dongping

2018-01-01

Neuroma formation after peripheral nerve transection leads to severe neuropathic pain in amputees. Previous studies suggested that physical exercise could bring beneficial effect on alleviating neuropathic pain. However, the effect of exercise on neuroma pain still remained unclear. In addition, long-term exercise can affect the expression of neurotrophins (NT), such as nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF), which play key roles in nociceptor sensitization and nerve sprouting after nerve injury. Here, we investigated whether long-term swimming exercise could relieve neuroma pain by modulating NT expression. We used a tibial neuroma transposition (TNT) rat model to mimic neuroma pain. After TNT surgery, rats performed swimming exercise for 5 wk. Neuroma pain and tactile sensitivities were detected using von Frey filaments. Immunofluorescence was applied to analyze neuroma formation. NGF and BDNF expressions in peripheral neuroma, dorsal root ganglion, and the spinal cord were measured using enzyme-linked immunosorbent assay and Western blotting. TNT led to neuroma formation, induced neuroma pain, and mechanical allodynia in hind paw. Five-week swimming exercise inhibited neuroma formation and relieved mechanical allodynia in the hind paw and neuroma pain in the lateral ankle. The analgesic effect lasted for at least 1 wk, even when the exercise ceased. TNT elevated the expressions of BDNF and NGF in peripheral neuroma, dorsal root ganglion, and the spinal cord to different extents. Swimming also decreased the elevation of NT expression. Swimming exercise not only inhibits neuroma formation induced by nerve transection but also relieves pain behavior. These effects might be associated with the modulation of NT.

TRANSRECTAL ULTRASONOGRAPHY OF EQUINE LUMBOSACRAL NERVES: PILOT STUDY IN 28 HEALTHY WARMBLOOD HORSES.

PubMed

Espinosa, Pablo; Benoit, Philippe; Salazar, Isabel; de la Fuente, Jesús; Heiles, Philippe

2017-03-01

A noninvasive method for visualizing lumbosacral nerves would be helpful for horses with suspected lumbosacral plexopathy or injury. The aim of this prospective descriptive pilot study was to characterize the ultrasonographic appearance of the lumbosacral nerves in a sample of healthy horses, and expand on the technique for image acquisition. Horses were recruited for inclusion if they were determined to be healthy and sound based on clinical and lameness evaluation. Transrectal ultrasound images of the lumbosacral nerves (L6, S1, and S2) were obtained for both sides. Landmarks for localization, and techniques for nerve identification and measurement were described. Effects of sex, age, side, and nerve on measured thickness were statistically tested. Twenty-eight warmblood horses were sampled (15 males and 13 females). Ages ranged from 5 to 15 years. Ventral nerve roots from L6 to S2 appeared as tubular structures with a characteristic hyperechoic linear echo pattern. There was no significant difference in nerve vertical diameter between left and right sides. A three-way interaction was found among sex, age and lumbosacral nerve. The L6 nerve in males was significantly larger than S1 only in the youngest group. The S2 nerve was significantly smaller than L6 or S1 regardless of age group or sex. In conclusion, transrectal ultrasound was a feasible method for visualizing and measuring equine lumbosacral nerves. Wide ranges of sizes for each nerve were found between horses, however nerves were bilaterally symmetrical within horses. Side comparison is therefore recommended when nerve pathology is suspected. © 2016 American College of Veterinary Radiology.

[Accidental injection of sodium hypochlorite in inferior alveolar nerve block anesthesia].

PubMed

Hongyan, Li; Jian, Xu; Baorong, Zhang; Yue, Jia; Minhua, Liu; Yilang, Luo; Jing, Zhao

2016-12-01

Sodium hypochlorite (NaClO) has been widely used in clinical practice as one of the most efficient root canal irrigants. Its properties include broad-spectrum antimicrobial activity and ability to dissolve necrotic tissues. However, when used improperly, NaClO can cause a series of adverse reactions, such as mucosal inflammation, irritation, or injury. This paper presents a case of accidental injection of NaClO in inferior alveolar nerve block anesthesia.

Use of GDNF-Releasing Nanofiber Nerve Guide Conduits for the Repair of Conus Medullaris/Cauda Equina Injury in the Non-Human Primate

DTIC Science & Technology

2012-10-01

peripheral nerve graft to bridge the tissue gap. A comprehensive set of electrodiagnostic, imaging , behavioral and anatomical studies will provide...spinal cord and avulsed ventral roots. All 20 surgeries have been completed and collections of comprehensive functional and imaging data are in...gap. A comprehensive set of electrodiagnostic, imaging , behavioral and anatomical studies will provide detailed information about the outcome of the

Use of GDNF Releasing Nanofiber Nerve Guide Conduits for the Repair of Conus Medullaris/Cauda Equina Injury in the Nonhuman Primate

DTIC Science & Technology

2015-02-01

repair of conus medullaris/cauda equina injury in rhesus macaques using a biodegradable bridging graft that releasing the trophic factor, GDNF. All...and biodegradable nerve guidance channels as bridging grafts. The follow section describes the methods and protocols for laminectomy, ventral root...in saline until being grafted, 8. For use of a bridging biodegradable NGC segment, the NGCs were fabricated and comprised of electrospun

Nerve damage in dentistry.

PubMed

Pogrel, M Anthony

2017-01-01

Many forms of dental treatment have the potential to cause injury to the oral branches of the trigeminal nerve, including local anesthetic injections, root canal therapy, implant insertion, bone grafting, and dentoalveolar surgery. Based on the records of a referral center with more than 30 years' experience in managing 3200 of these injuries, this article reviews etiology and prevention; suggests criteria for referral of patients; and discusses treatment for the various types of injury and the results of such treatment.

Downregulation of ClC-3 in dorsal root ganglia neurons contributes to mechanical hypersensitivity following peripheral nerve injury.

PubMed

Pang, Rui-Ping; Xie, Man-Xiu; Yang, Jie; Shen, Kai-Feng; Chen, Xi; Su, Ying-Xue; Yang, Chao; Tao, Jing; Liang, Si-Jia; Zhou, Jia-Guo; Zhu, He-Quan; Wei, Xu-Hong; Li, Yong-Yong; Qin, Zhi-Hai; Liu, Xian-Guo

2016-11-01

ClC-3 chloride channel/antiporter has been demonstrated to play an important role in synaptic transmission in central nervous system. However, its expression and function in sensory neurons is poorly understood. In present work, we found that ClC-3 is expressed at high levels in dorsal root ganglia (DRG). Co-immunofluorescent data showed that ClC-3 is mainly distributed in A- and C-type nociceptive neurons. ClC-3 expression in DRG is decreased in the spared nerve injury (SNI) model of neuropathic pain. Knockdown of local ClC-3 in DRG neurons with siRNA increased mechanical sensitivity in naïve rats, while overexpression of ClC-3 reversed the hypersensitivity to mechanical stimuli after peripheral nerve injury. In addition, genetic deletion of ClC-3 enhances mouse mechanical sensitivity but did not affect thermal and cold threshold. Restoration of ClC-3 expression in ClC-3 deficient mice reversed the mechanical sensitivity. Mechanistically, loss of ClC-3 enhanced mechanical sensitivity through increasing the excitability of DRG neurons. These data indicate that ClC-3 is an endogenous inhibitor of neuropathic pain development. Downregulation of ClC-3 by peripheral nerve injury is critical for mechanical hypersensitivity. Our findings suggest that ClC-3 is a novel therapeutic target for treating neuropathic pain. Copyright © 2016 Elsevier Ltd. All rights reserved.

Role of dorsal root ganglion K2P1.1 in peripheral nerve injury-induced neuropathic pain

PubMed Central

Mao, Qingxiang; Yuan, Jingjing; Xiong, Ming; Wu, Shaogen; Chen, Liyong; Bekker, Alex; Yang, Tiande

2017-01-01

Peripheral nerve injury-caused hyperexcitability and abnormal ectopic discharges in the primary sensory neurons of dorsal root ganglion (DRG) play a key role in neuropathic pain development and maintenance. The two-pore domain background potassium (K2P) channels have been identified as key determinants of the resting membrane potential and neuronal excitability. However, whether K2P channels contribute to neuropathic pain is still elusive. We reported here that K2P1.1, the first identified mammalian K2P channel, was highly expressed in mouse DRG and distributed in small-, medium-, and large-sized DRG neurons. Unilateral lumbar (L) 4 spinal nerve ligation led to a significant and time-dependent reduction of K2P1.1 mRNA and protein in the ipsilateral L4 DRG, but not in the contralateral L4 or ipsilateral L3 DRG. Rescuing this reduction through microinjection of adeno-associated virus-DJ expressing full-length K2P1.1 mRNA into the ipsilateral L4 DRG blocked spinal nerve ligation-induced mechanical, thermal, and cold pain hypersensitivities during the development and maintenance periods. This DRG viral microinjection did not affect acute pain and locomotor function. Our findings suggest that K2P1.1 participates in neuropathic pain development and maintenance and may be a potential target in the management of this disorder. PMID:28326939

Peptidomics and Secretomics of the Mammalian Peripheral Sensory-Motor System

NASA Astrophysics Data System (ADS)

Tillmaand, Emily G.; Yang, Ning; Kindt, Callie A. C.; Romanova, Elena V.; Rubakhin, Stanislav S.; Sweedler, Jonathan V.

2015-12-01

The dorsal root ganglion (DRG) and its anatomically and functionally associated spinal nerve and ventral and dorsal roots are important components of the peripheral sensory-motor system in mammals. The cells within these structures use a number of peptides as intercellular signaling molecules. We performed a variety of mass spectrometry (MS)-based characterizations of peptides contained within and secreted from these structures, and from isolated and cultured DRG cells. Liquid chromatography-Fourier transform MS was utilized in DRG and nerve peptidome analysis. In total, 2724 peptides from 296 proteins were identified in tissue extracts. Neuropeptides are among those detected, including calcitonin gene-related peptide I, little SAAS, and known hemoglobin-derived peptides. Solid phase extraction combined with direct matrix-assisted laser desorption/ionization time-of-flight MS was employed to investigate the secretome of these structures. A number of peptides were detected in the releasate from semi-intact preparations of DRGs and associated nerves, including neurofilament- and myelin basic protein-related peptides. A smaller set of analytes was observed in releasates from cultured DRG neurons. The peptide signals observed in the releasates have been mass-matched to those characterized and identified in homogenates of entire DRGs and associated nerves. This data aids our understanding of the chemical composition of the mammalian peripheral sensory-motor system, which is involved in key physiological functions such as nociception, thermoreception, itch sensation, and proprioception.

Peptidomics and Secretomics of the Mammalian Peripheral Sensory-Motor System.

PubMed

Tillmaand, Emily G; Yang, Ning; Kindt, Callie A C; Romanova, Elena V; Rubakhin, Stanislav S; Sweedler, Jonathan V

2015-12-01

The dorsal root ganglion (DRG) and its anatomically and functionally associated spinal nerve and ventral and dorsal roots are important components of the peripheral sensory-motor system in mammals. The cells within these structures use a number of peptides as intercellular signaling molecules. We performed a variety of mass spectrometry (MS)-based characterizations of peptides contained within and secreted from these structures, and from isolated and cultured DRG cells. Liquid chromatography-Fourier transform MS was utilized in DRG and nerve peptidome analysis. In total, 2724 peptides from 296 proteins were identified in tissue extracts. Neuropeptides are among those detected, including calcitonin gene-related peptide I, little SAAS, and known hemoglobin-derived peptides. Solid phase extraction combined with direct matrix-assisted laser desorption/ionization time-of-flight MS was employed to investigate the secretome of these structures. A number of peptides were detected in the releasate from semi-intact preparations of DRGs and associated nerves, including neurofilament- and myelin basic protein-related peptides. A smaller set of analytes was observed in releasates from cultured DRG neurons. The peptide signals observed in the releasates have been mass-matched to those characterized and identified in homogenates of entire DRGs and associated nerves. This data aids our understanding of the chemical composition of the mammalian peripheral sensory-motor system, which is involved in key physiological functions such as nociception, thermoreception, itch sensation, and proprioception.

Spatial patterns of Armillaria populations in the walker branch watershed throughfall displacement experiment, Tennessee,USA.

Treesearch

Johann N. Bruhn; James A. Brenneman; James J., Jr. Wetteroff; Jeanne D. Mihail; Theodor D. Leininger

1997-01-01

Species in the white-rot fungal genus Armillaria vary in parasitic aggressiveness as root and butt rot pathogens of trees. Armillaria genets (individuals) were mapped in the Throughfall Displacement Experiment (TDE) using mushrooms and rhizomorphs collected in 1994 and 1995. Initiated in July 1993, the TDE consists of three 80 x 80...

Management of an unusual sciatica.

PubMed

Bourghli, Anouar; Chaballout, Ahmed; Obeid, Ibrahim; Boissiere, Louis; Vital, Jean-Marc; Khoury, Ghassan

2016-11-01

Extraforaminal entrapment of the L5 nerve root is uncommon, and its management can sometimes be very challenging. We present the case of a 57-year-old female, complaining of a sciatica in her left leg, for 3 years, with no response to any kind of conservative treatment. MRI and CT scan revealed the presence of a large L5S1 strictly lateral osteophyte compressing the left L5 root in its extraforaminal path. The patient underwent a left anterior retroperitoneal approach with assistance from a vascular surgeon given the very close relation between the osteophyte and the left common iliac vein, lying just on top of it, osteophyte was removed in one piece with the use of an osteotome after retraction of the vessels. The patient progressively recovered from her left sciatic pain with a satisfactory clinical result at 1 year. Literature is sparse on the treatment of extraforaminal entrapment of the L5 nerve root; the current case shows a successful treatment strategy with the use of an anterior approach for direct vision of the lesion and good control of the vessels.

Intractable Pruritus After Traumatic Spinal Cord Injury

PubMed Central

Crane, Deborah A; Jaffee, Kenneth M; Kundu, Anjana

2009-01-01

Background: This report describes a young woman with incomplete traumatic cervical spinal cord injury and intractable pruritus involving her dorsal forearm. Method: Case report. Findings: Anatomic distribution of the pruritus corresponded to the dermatomal distribution of her level of spinal cord injury and vertebral fusion. Symptoms were attributed to the spinal cord injury and possible cervical root injury. Pruritus was refractory to all treatments, including topical lidocaine, gabapentin, transcutaneous electrical nerve stimulation, intravenous Bier block, stellate ganglion block, and acupuncture. Conclusions: Further understanding of neuropathic pruritus is needed. Diagnostic workup of intractable pruritus should include advanced imaging to detect ongoing nerve root compression. If diagnostic studies suggest radiculopathy, epidural steroid injection should be considered. Because the autonomic nervous system may be involved in complex chronic pain or pruritic syndromes, sympatholysis via such techniques as stellate ganglion block might be effective. PMID:19777867

Cells of origin in the embryonic nerve roots for NF1-associated plexiform neurofibroma

PubMed Central

Chen, Zhiguo; Liu, Chiachi; Patel, Amish J.; Liao, Chung-Ping; Wang, Yong; Le, Lu Q.

2014-01-01

Summary Neurofibromatosis type 1 is a tumor-predisposing genetic disorder. Plexiform neurofibromas are common NF1 tumors carrying a risk of malignant transformation, which is typically fatal. Little is known about mechanisms mediating initiation and identity of specific cell-type that gives rise to neurofibromas. Using cell-lineage tracing, we identify a population of GAP43+ PLP+ precursors in embryonic nerve roots as the cells of origin for these tumors and report a non-germline model of neurofibroma for preclinical drug screening to identify effective therapies. The identity of tumor cell-of-origin and facility for isolation and expansion provides fertile ground for continued analysis to define intrinsic and extrinsic factors critical for neurofibromagenesis. It also provides unique approaches to develop therapies to prevent neurofibroma formation in NF1 patients. PMID:25446898

Agreement between computed tomography, magnetic resonance imaging, and surgical findings in dogs with degenerative lumbosacral stenosis.

PubMed

Suwankong, Niyada; Voorhout, George; Hazewinkel, Herman A W; Meij, Björn P

2006-12-15

To assess the extent of agreement between computed tomography (CT), magnetic resonance imaging (MRI), and surgical findings in dogs with degenerative lumbosacral stenosis. Observational study. 35 dogs with degenerative lumbosacral stenosis. Results of preoperative CT and MRI were compared with surgical findings with respect to degree and location of disk protrusion, position of the dural sac, amount of epidural fat, and swelling of spinal nerve roots. A lumbosacral step was seen on radiographic images from 22 of 32 (69%) dogs, on CT images from 23 of 35 (66%) dogs, and on MR images from 21 of 35 (60%) dogs. Most dogs had slight or moderate disk protrusion that was centrally located. There was substantial or near perfect agreement between CT and MRI findings in regard to degree of disk protrusion (kappa, 0.88), location of disk protrusion (0.63), position of the dural sac (0.89), amount of epidural fat (0.72), and swelling of spinal nerve roots (0.60). The degree of agreement between CT and surgical findings and between MRI and surgical findings was moderate in regard to degree and location of disk protrusion (kappa, 0.44 to 0.56) and swelling of spinal nerve roots (0.40 and 0.50). Results indicate that there is a high degree of agreement between CT and MRI findings in dogs with degenerative lumbosacral stenosis but that the degree of agreement between diagnostic imaging findings and surgical findings is lower.

Non-invasive electrical and magnetic stimulation of the brain, spinal cord, roots and peripheral nerves: Basic principles and procedures for routine clinical and research application. An updated report from an I.F.C.N. Committee.

PubMed

Rossini, P M; Burke, D; Chen, R; Cohen, L G; Daskalakis, Z; Di Iorio, R; Di Lazzaro, V; Ferreri, F; Fitzgerald, P B; George, M S; Hallett, M; Lefaucheur, J P; Langguth, B; Matsumoto, H; Miniussi, C; Nitsche, M A; Pascual-Leone, A; Paulus, W; Rossi, S; Rothwell, J C; Siebner, H R; Ugawa, Y; Walsh, V; Ziemann, U

2015-06-01

These guidelines provide an up-date of previous IFCN report on "Non-invasive electrical and magnetic stimulation of the brain, spinal cord and roots: basic principles and procedures for routine clinical application" (Rossini et al., 1994). A new Committee, composed of international experts, some of whom were in the panel of the 1994 "Report", was selected to produce a current state-of-the-art review of non-invasive stimulation both for clinical application and research in neuroscience. Since 1994, the international scientific community has seen a rapid increase in non-invasive brain stimulation in studying cognition, brain-behavior relationship and pathophysiology of various neurologic and psychiatric disorders. New paradigms of stimulation and new techniques have been developed. Furthermore, a large number of studies and clinical trials have demonstrated potential therapeutic applications of non-invasive brain stimulation, especially for TMS. Recent guidelines can be found in the literature covering specific aspects of non-invasive brain stimulation, such as safety (Rossi et al., 2009), methodology (Groppa et al., 2012) and therapeutic applications (Lefaucheur et al., 2014). This up-dated review covers theoretical, physiological and practical aspects of non-invasive stimulation of brain, spinal cord, nerve roots and peripheral nerves in the light of more updated knowledge, and include some recent extensions and developments. Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Peripheral Nerve Repair in Rats Using Composite Hydrogel-Filled Aligned Nanofiber Conduits with Incorporated Nerve Growth Factor

PubMed Central

Jin, Jenny; Limburg, Sonja; Joshi, Sunil K.; Landman, Rebeccah; Park, Michelle; Zhang, Qia; Kim, Hubert T.

2013-01-01

Repair of peripheral nerve defects with current synthetic, tubular nerve conduits generally shows inferior recovery when compared with using nerve autografts, the current gold standard. We tested the ability of composite collagen and hyaluronan hydrogels, with and without the nerve growth factor (NGF), to stimulate neurite extension on a promising aligned, nanofiber poly-L-lactide-co-caprolactone (PLCL) scaffold. In vitro, the hydrogels significantly increased neurite extension from dorsal root ganglia explants. Consistent with these results, the addition of hydrogels as luminal fillers within aligned, nanofiber tubular PLCL conduits led to improved sensory function compared to autograft repair in a critical-size defect in the sciatic nerve in a rat model. Sensory recovery was assessed 3 and 12 weeks after repair using a withdrawal assay from thermal stimulation. The addition of hydrogel did not enhance recovery of motor function in the rat model. The NGF led to dose-dependent improvements in neurite out-growth in vitro, but did not have a significant effect in vivo. In summary, composite collagen/hyaluronan hydrogels enhanced sensory neurite outgrowth in vitro and sensory recovery in vivo. The use of such hydrogels as luminal fillers for tubular nerve conduits may therefore be useful in assisting restoration of protective sensation following peripheral nerve injury. PMID:23659607

Characterization of Cadmium Uptake by Plant Tissue 12

PubMed Central

Cutler, Jay M.; Rains, Donald W.

1974-01-01

The uptake of cadmium by excised root tissue of barley (Hordeum vulgare L. cv. Arivat) was investigated with respect to kinetics, concentration, and interactions with various cations. The role of metabolism in Cd absorption was examined using a range of temperatures, anaerobic treatments, and chemical inhibitors. The uptake and distribution of Cd in intact barley plants was also determined. A large fraction of the Cd taken up by excised barley roots was apparently the result of exchange adsorption and was displaced by subsequent desorption with unlabeled Cd, Zn, Cu, or Hg. Another fraction of Cd which could not be displaced by desorption in unlabeled Cd was thought to result from strong irreversible binding of Cd, perhaps on sites of the cell wall. The fraction of the Cd taken up beyond that by exchange adsorption by fresh roots was a linear function of temperature, and inhibited by conditions of low oxygen and by the presence of 2,4-dinitrophenol. It was concluded that this fraction of Cd entered excised barley roots by diffusion. Diffusion, when followed by sequestering, probably accounts for the accumulation of Cd observed in intact barley plants. PMID:16658840

Topographical and functional anatomy of trapezius muscle innervation by spinal accessory nerve and C2 to C4 nerves of cervical plexus.

PubMed

Gavid, M; Mayaud, A; Timochenko, A; Asanau, A; Prades, J M

2016-10-01

The aim of this study was to determine the existence and the frequency of communicating branches between the spinal accessory nerve (SAN) and the C2, C3 and C4 roots of the cervical plexus. The present study also aimed to elucidate whether these branches contain motor fibers or not. Dissection of the cervical region was performed on twelve adult cadavers. A powered operating microscope was necessary to dissect the SAN and its branches and also to dissect C2, C3 and C4 nerve branches. In a second step, data from 13 patients who underwent 25 modified neck dissections under trapezius muscle's monitoring were collected. At the end of surgery, intraoperative stimulation on the SAN, C2, C3 and C4 nerve branches was performed. Registered potentials in the three parts of the trapezius muscle, using the NIM Medtronic system, were analyzed. During cadaver dissection, 18 (78 %) communicating branches were identified between the SAN and C2, 11 (48 %) between the SAN and C3, 12 (52 %) between the SAN and C4. Intraoperative stimulation of the SAN and its branch for the trapezius muscle provided a significant electroneurographic response in the three parts of the trapezius muscle in all subjects. Intraoperative stimulation of C3 led to recordable contractions of the trapezius muscle in 5 (20 %) modified neck surgeries, stimulation of C4 led to recordable contractions during 5 (20 %) modified neck dissections. One case of contraction was recorded after intraoperative stimulation of C2 (7 %). Although we were able to identify at least one communicating branch between the SAN and the roots of the cervical plexus in each cadaver dissection, the cervical plexus is not always involved in trapezius motor innervation. Intraoperative electroneurography demonstrated that a motor input from the cervical plexus to the trapezius muscle was provided in only 32 % of cases. Therefore, SAN trunk and C3-C4 roots should be carefully preserved during modified neck dissection to protect trapezius and shoulder functions.

Flare-up with associated paresthesia of a mandibular second premolar with three root canals.

PubMed

Glassman, G D

1987-07-01

A case report is presented that deals with mental nerve paresthesia resulting from the "flare-up" of a mandibular second premolar with three root canals. A review of the literature and discussion follow, which suggest possible mechanisms that may be responsible for paresthesia as well as treatment regimens that may be used to minimize the incidence of this unexpected but occasional post-treatment endodontic sequela.

[A rare cause of optic neuropathy: Cassava].

PubMed

Zeboulon, P; Vignal-Clermont, C; Baudouin, C; Labbé, A

2016-06-01

Cassava root is a staple food for almost 500 million people worldwide. Excessive consumption of it is a rare cause of optic neuropathy. Ten patients diagnosed with cassava root related optic neuropathy were included in this retrospective study. Diagnostic criteria were a bilateral optic neuropathy preceded by significant cassava root consumption. Differential diagnoses were excluded through a neuro-ophthalmic examination, blood tests and a brain MRI. All patients had visual field examination and OCT retinal nerve fiber layer (RNFL) analysis as well as an evaluation of their cassava consumption. All patients had a bilateral optic nerve head atrophy or pallor predominantly located into the temporal sector. Visual field defects consisted of a central or cecocentral scotoma for all patients. RNFL showed lower values only in the temporal sector. Mean duration of cassava consumption prior to the appearance of visual symptoms was 22.7±11.2 years with a mean of 2.57±0.53 cassava-based meals per week. Cassava related optic neuropathy is possibly due to its high cyanide content and enabled by a specific amino-acid deficiency. Cassava root chronic consumption is a rare, underappreciated cause of optic neuropathy and its exact mechanism is still uncertain. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

The prognostic value of panoramic radiography of inferior alveolar nerve damage after mandibular third molar removal: retrospective study of 400 cases.

PubMed

Szalma, József; Lempel, Edina; Jeges, Sára; Szabó, Gyula; Olasz, Lajos

2010-02-01

The aim of the study was to estimate the accuracy of panoramic radiographic signs predicting inferior alveolar nerve (IAN) paresthesia after lower third molar removal. In a case-control study the sample was composed of 41 cases with postoperative IAN paresthesia and 359 control cases without it. The collected data included "classic" specific signs indicating a close spatial relationship between third molar root and inferior alveolar canal (IAC), root curvatures, and the extent of IAC-root tip overlap. Bivariate and multivariate logistic regression analyses were completed to estimate the association between radiographic findings and IAN paresthesia. The multivariate logistic analysis identified 3 signs significantly associated with IAN paresthesia (P < .001): interruption of the superior cortex of the canal wall, diversion of the canal, and darkening of the root. The sensitivities and specificities ranged from 14.6% to 68.3% and from 85.5% to 96.9%, respectively. The positive predictive values, calculated to factor a 1.1% prevalence of paresthesia, ranged from 3.6% to 10.9%, whereas the negative predictive values >99%. Panoramic radiography is an inadequate screening method for predicting IAN paresthesia after mandibular third molar removal. Copyright (c) 2010 Mosby, Inc. All rights reserved.

The interaction between intracranial pressure, intraocular pressure and lamina cribrosal compression in glaucoma.

PubMed

McMonnies, Charles W

2016-05-01

This review examines some of the biomechanical consequences associated with the opposing intraocular and intracranial forces. These forces compress the lamina cribrosa and are a potential source of glaucomatous pathology. A difference between them creates a displacement force on the lamina cribrosa. Increasing intraocular pressure and/or decreasing intracranial pressure will increase the trans-lamina cribrosa pressure difference and the risk of its posterior displacement, canal expansion and the formation of pathological cupping. Both intraocular pressure and intracranial pressure can be elevated during a Valsalva manoeuvre with associated increases in both anterior and posterior lamina cribrosa loading as well as its compression. Any resulting thinning of or damage to the lamina cribrosa and/or retinal ganglion cell axons and/or astrocyte and glial cells attached to the matrix of the lamina cribrosa and/or reduction in blood flow to the lamina cribrosa may contribute to glaucomatous neuropathy. Thinning of the lamina cribrosa reduces its stiffness and increases the risk of its posterior displacement. Optic nerve head posterior displacement warrants medical or surgical lowering of intraocular pressure; however, compared to intraocular pressure, the trans-lamina cribrosa pressure difference may be more important in pressure-related pathology of the optic nerve head region. Similarly important could be increased compression loading of the lamina cribrosa. Reducing participation in activities which elevate intraocular and intracranial pressure will decrease lamina cribrosa compression exposure and may contribute to glaucoma management and may have prognostic significance for glaucoma suspects. © 2016 The Authors. Clinical and Experimental Optometry © 2016 Optometry Australia.

Effects of aortic root motion on wall stress in the Marfan aorta before and after personalised aortic root support (PEARS) surgery.

PubMed

Singh, S D; Xu, X Y; Pepper, J R; Izgi, C; Treasure, T; Mohiaddin, R H

2016-07-05

Aortic root motion was previously identified as a risk factor for aortic dissection due to increased longitudinal stresses in the ascending aorta. The aim of this study was to investigate the effects of aortic root motion on wall stress and strain in the ascending aorta and evaluate changes before and after implantation of personalised external aortic root support (PEARS). Finite element (FE) models of the aortic root and thoracic aorta were developed using patient-specific geometries reconstructed from pre- and post-PEARS cardiovascular magnetic resonance (CMR) images in three Marfan patients. The wall and PEARS materials were assumed to be isotropic, incompressible and linearly elastic. A static load on the inner wall corresponding to the patients' pulse pressure was applied. Cardiovascular MR cine images were used to quantify aortic root motion, which was imposed at the aortic root boundary of the FE model, with zero-displacement constraints at the distal ends of the aortic branches and descending aorta. Measurements of the systolic downward motion of the aortic root revealed a significant reduction in the axial displacement in all three patients post-PEARS compared with its pre-PEARS counterparts. Higher longitudinal stresses were observed in the ascending aorta when compared with models without the root motion. Implantation of PEARS reduced the longitudinal stresses in the ascending aorta by up to 52%. In contrast, the circumferential stresses at the interface between the supported and unsupported aorta were increase by up to 82%. However, all peak stresses were less than half the known yield stress for the dilated thoracic aorta. Copyright © 2016 Elsevier Ltd. All rights reserved.

Axonal degeneration and regeneration in sensory roots in a genital herpes model.

PubMed

Soffer, D; Martin, J R

1989-01-01

In a mouse model of genital herpes simplex virus type 2 (HSV-2) infection, roots of the lower spinal cord were examined 5 days to 6 months after inoculation. Using immunoperoxidase methods on paraffin sections, viral antigen was found in sensory ganglia, their proximal roots and distal nerves on days 5 and 6 after infection. In Epon sections, most mice had focal sensory root abnormalities in lower thoracic, lumbar or sacral levels. At days 7 and 10, lesions showed chiefly nerve fiber degeneration, particularly of large myelinated fibers. At 2 weeks, lesions contained relatively large bundles of small unmyelinated fibers with immature axon-Schwann cell relationships. From 3 to 6 weeks, lesions again contained many more small unmyelinated fibers than normal but, in increasing proportions, axons in bundles were isolated from their neighbors by Schwann cell cytoplasm, and Schwann cells having 1:1 relationships with axons showed mesaxon or thin myelin sheath formation. At later times, the proportion of small unmyelinated axons decreased in parallel with increased numbers of small myelinated axons. By 6 months, affected roots showed a relative reduction in large myelinated fibers, increased proportions of small myelinated fibers and Schwann cell nuclei. Numbers of unmyelinated fibers were reduced relative to 3- to 6-week lesions. Axonal degeneration and regeneration appears to be the chief pathological change in sensory roots in this model. If regenerated fibers arise from latently infected neurons, then establishment of latency is not a relatively silent event, but is associated with major long-lasting, morphologically detectable effects.

High-resolution nerve ultrasound and magnetic resonance neurography as complementary neuroimaging tools for chronic inflammatory demyelinating polyneuropathy

PubMed Central

Pitarokoili, Kalliopi; Kronlage, Moritz; Bäumer, Philip; Schwarz, Daniel; Gold, Ralf; Bendszus, Martin; Yoon, Min-Suk

2018-01-01

Background: We present a clinical, electrophysiological, sonographical and magnetic resonance neurography (MRN) study examining the complementary role of two neuroimaging methods of the peripheral nervous system for patients with chronic inflammatory demyelinating polyneuropathy (CIDP). Furthermore, we explore the significance of cross-sectional area (CSA) increase through correlations with MRN markers of nerve integrity. Methods: A total of 108 nerve segments on the median, ulnar, radial, tibial and fibular nerve, as well as the lumbar and cervical plexus of 18 CIDP patients were examined with high-resonance nerve ultrasound (HRUS) and MRN additionally to the nerve conduction studies. Results: We observed a fair degree of correlation of the CSA values for all nerves/nerve segments between the two methods, with a low random error in Bland–Altman analysis (bias = HRUS-CSA − MRN-CSA, −0.61 to −3.26 mm). CSA in HRUS correlated with the nerve T2-weighted (nT2) signal increase as well as with diffusion tensor imaging parameters such as fractional anisotropy, a marker of microstructural integrity. HRUS-CSA of the interscalene brachial plexus correlated significantly with the MRN-CSA and nT2 signal of the L5 and S1 roots of the lumbar plexus. Conclusions: HRUS allows for reliable CSA imaging of all peripheral nerves and the cervical plexus, and CSA correlates with markers of nerve integrity. Imaging of proximal segments as well as the estimation of nerve integrity require MRN as a complementary method. PMID:29552093

In vivo anatomical analysis of arterial contact with trigeminal nerve: detection with three-dimensional spoiled grass imaging.

PubMed

Ueda, F; Suzuki, M; Fujinaga, Y; Kadoya, M; Takashima, T

1999-09-01

The purpose of this study was to review the normal in vivo neurovascular relationship between the trigeminal nerve and surrounding arteries without the use of volunteers. 290 nerves in 145 cases were reviewed during a 1-year period. Axial source images and multiplanar reconstructed (MPR) images were used to determine the neurovascular contact and direction of contact. Multiplanar volume reformation (MPVR) was used to identify the contact vessels and to demonstrate the relationship between the nerve and arteries. Vascular contact was found in 29% of the 290 nerves (83 nerves). The arteries involved were the superior cerebellar artery (SCA) or the anterior inferior cerebellar artery (AICA). Vascular contact with two arteries was found in 3%. Of the 286 asymptomatic nerves, the nerve was located between the two vessels in 3% and compression was seen in 1%. Three points of vascular contact by the two arteries were identified in one asymptomatic nerve. The direction of contact between the SCA and the nerve was superior (38%), superomedial (32%) or medial (15%) in most cases. The direction of contact between the AICA and the nerve was inferior, inferolateral or lateral in all cases. Vascular contact at the root entry zone (REZ) was noted in 90%. Four nerves were affected by trigeminal neuralgia, one of which touched an artery and two were compressed. It was concluded that arterial contact can be assessed without difficulty but evaluation of vascular compression is not easy.

Can proximity of the occipital artery to the greater occipital nerve act as a cause of idiopathic greater occipital neuralgia? An anatomical and histological evaluation of the artery-nerve relationship.

PubMed

Shimizu, Satoru; Oka, Hidehiro; Osawa, Shigeyuki; Fukushima, Yutaka; Utsuki, Satoshi; Tanaka, Ryusui; Fujii, Kiyotaka

2007-06-01

The purpose of this study was to clarify whether proximity of the occipital artery to the greater occipital nerve can act as a cause of occipital neuralgia, analogous to the contribution of intracranial vessels due to compression in cranial nerve neuralgias, represented by trigeminal neuralgias due to compression of the trigeminal nerve root by adjacent arterial loops. Twenty-four suboccipital areas in cadaver heads were studied for anatomical relationships between the occipital artery and the greater occipital nerve, with histopathological assessment of the greater occipital nerve for signs of mechanical damage. The occipital artery and greater occipital nerve were found to cross each other in the nuchal subcutaneous layer, and the latter was constantly situated superficial to the former at the cross point. An indentation of the greater occipital nerve due to the occipital artery was observed at the cross point in all specimens. However, histopathological examination did not reveal any findings of damage to nerves, even in specimens with atherosclerosis of the occipital artery. Although the present study did not provide direct evidence that the occipital artery contributes to occipital neuralgia at the point of contact with the greater occipital nerve, the possibility still cannot be precluded, because the occipital artery may be palpable in areas corresponding to tenderness of the greater occipital nerve. Further studies, including clinical cases, are needed to clarify this issue.

Technical refinement and learning curve for attenuating neurapraxia during robotic-assisted radical prostatectomy to improve sexual function.

PubMed

Alemozaffar, Mehrdad; Duclos, Antoine; Hevelone, Nathanael D; Lipsitz, Stuart R; Borza, Tudor; Yu, Hua-Yin; Kowalczyk, Keith J; Hu, Jim C

2012-06-01

While radical prostatectomy surgeon learning curves have characterized less blood loss, shorter operative times, and fewer positive margins, there is a dearth of studies characterizing learning curves for improving sexual function. Additionally, while learning curve studies often define volume thresholds for improvement, few of these studies demonstrate specific technical modifications that allow reproducibility of improved outcomes. Demonstrate and quantify the learning curve for improving sexual function outcomes based on technical refinements that reduce neurovascular bundle displacement during nerve-sparing robot-assisted radical prostatectomy (RARP). We performed a retrospective study of 400 consecutive RARPs, categorized into groups of 50, performed after elimination of continuous surgeon/assistant neurovascular bundle countertraction. Our approach to RARP has been described previously. A single-console robotic system was used for all cases. Expanded Prostate Cancer Index Composite sexual function was measured within 1 yr of RARP. Linear regression was performed to determine factors influencing the recovery of sexual function. Greater surgeon experience was associated with better 5-mo sexual function (p = 0.007) and a trend for better 12-mo sexual function (p = 0.061), with improvement plateauing after 250-300 cases. Additionally, younger patient age (both p<0.02) and better preoperative sexual function (<0.001) were associated with better 5- and 12-mo sexual function. Moreover, trainee robotic console time during nerve sparing was associated with worse 12-mo sexual function (p=0.021), while unilateral nerve sparing/non-nerve sparing was associated with worse 5-mo sexual function (p = 0.009). Limitations include the retrospective single-surgeon design. With greater surgeon experience, attenuating lateral displacement of the neurovascular bundle and resultant neurapraxia improve postoperative sexual function. However, to maximize outcomes, appropriate patient selection must be exercised when allowing trainee nerve-sparing involvement. Copyright © 2012 European Association of Urology. Published by Elsevier B.V. All rights reserved.

Imaging of radicals following injury or acute stress in peripheral nerves with activatable fluorescent probes.

PubMed

Zhou, Haiying; Yan, Ying; Ee, Xueping; Hunter, Daniel A; Akers, Walter J; Wood, Matthew D; Berezin, Mikhail Y

2016-12-01

Peripheral nerve injury evokes a complex cascade of chemical reactions including generation of molecular radicals. Conversely, the reactions within nerve induced by stress are difficult to directly detect or measure to establish causality. Monitoring these reactions in vivo would enable deeper understanding of the nature of the injury and healing processes. Here, we utilized near-infrared fluorescence molecular probes delivered via intra-neural injection technique to enable live, in vivo imaging of tissue response associated with nerve injury and stress. These initially quenched fluorescent probes featured specific sensitivity to hydroxyl radicals and become fluorescent upon encountering reactive oxygen species (ROS). Intraneurally delivered probes demonstrated rapid activation in injured rat sciatic nerve but minimal activation in normal, uninjured nerve. In addition, these probes reported activation within sciatic nerves of living rats after a stress caused by a pinprick stimulus to the abdomen. This imaging approach was more sensitive to detecting changes within nerves due to the induced stress than other techniques to evaluate cellular and molecular changes. Specifically, neither histological analysis of the sciatic nerves, nor the expression of pain and stress associated genes in dorsal root ganglia could provide statistically significant differences between the control and stressed groups. Overall, the results demonstrate a novel imaging approach to measure ROS in addition to the impact of ROS within nerve in live animals. Copyright © 2016 Elsevier Inc. All rights reserved.

Electron microscopy of human peripheral nerves of clinical relevance to the practice of nerve blocks. A structural and ultrastructural review based on original experimental and laboratory data.

PubMed

Reina, M A; Arriazu, R; Collier, C B; Sala-Blanch, X; Izquierdo, L; de Andrés, J

2013-12-01

The goal is to describe the ultrastructure of normal human peripheral nerves, and to highlight key aspects that are relevant to the practice of peripheral nerve block anaesthesia. Using samples of sciatic nerve obtained from patients, and dural sac, nerve root cuff and brachial plexus dissected from fresh human cadavers, an analysis of the structure of peripheral nerve axons and distribution of fascicles and topographic composition of the layers that cover the nerve is presented. Myelinated and unmyelinated axons, fascicles, epineurium, perineurium and endoneurium obtained from patients and fresh cadavers were studied by light microscopy using immunohistochemical techniques, and transmission and scanning electron microscopy. Structure of perineurium and intrafascicular capillaries, and its implications in blood-nerve barrier were revised. Each of the anatomical elements is analyzed individually with regard to its relevance to clinical practice to regional anaesthesia. Routine practice of regional anaesthetic techniques and ultrasound identification of nerve structures has led to conceptions, which repercussions may be relevant in future applications of these techniques. In this regard, the ultrastructural and histological perspective accomplished through findings of this study aims at enlightening arising questions within the field of regional anaesthesia. Copyright © 2013 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Published by Elsevier España. All rights reserved.

Radiologically determined orthodontically induced external apical root resorption in incisors after non-surgical orthodontic treatment of class II division 1 malocclusion: a systematic review.

PubMed

Tieu, Long D; Saltaji, Humam; Normando, David; Flores-Mir, Carlos

2014-07-23

This study aims to critically evaluate orthodontically induced external apical root resorption (OIEARR) in incisors of patients undergoing non-surgical orthodontic treatment of class II division 1 malocclusion by a systematic review of the published data. An electronic search of two databases was performed; the bibliographies of relevant articles were also reviewed. Studies were included if they examined the amount of OIEARR in incisors produced during non-surgical orthodontic treatment of individuals with class II division I malocclusion in the permanent dentition. Individuals had no previous history of OIEARR, syndromes, pathologies, or general diseases. Study selections, risk of bias assessment, and data extraction were performed in duplicate. Eight studies of moderate methodological quality were finally included. An increased prevalence (65.6% to 98.1%) and mild to moderate severity of OIEARR (<4 mm and <1/3 original root) were reported. No sex difference in root resorption was found. For the maxillary incisors, there was no evidence that either the central or lateral incisor was more susceptible to OIEARR. A weak to moderate positive correlation between treatment duration and root resorption, and anteroposterior apical displacement and root resorption was found. Current limited evidence suggests that non-surgical comprehensive orthodontic treatment to correct class II division 1 malocclusions causes increased prevalence and severity of OIEARR the more the incisor roots are displaced and the longer this movement takes.

Root canal

MedlinePlus

... top part of your tooth to expose the pulp. This is typically called access. Pulp is made up of nerves, blood vessels, and ... the tooth and runs to the jaw bone. Pulp supplies blood to a tooth and allows you ...

Effect of microstructure and notch root radius on fracture toughness of an aluminum metal matrix composite

NASA Technical Reports Server (NTRS)

Manoharan, M.; Lewandowski, J. J.

1989-01-01

Recent results on the effects of matrix aging condition (matrix temper) and notch root radius on the measured fracture toughness of a SiC particulate reinforced aluminum alloy are reviewed. Stress intensity factors at catastrophic fracture were obtained for both underaged and overaged composites reveal. The linear relation found between apparent fracture toughness and the square root of the notch root radius implies a linear dependence of the crack opening displacement on the notch root radius. The results suggest a strain controlled fracture process, and indicate that there are differences in the fracture micromechanisms of the two aging conditions.

Temporary Mental Nerve Paresthesia Originating from Periapical Infection

PubMed Central

Genc Sen, Ozgur; Kaplan, Volkan

2015-01-01

Many systemic and local factors can cause paresthesia, and it is rarely caused by infections of dental origin. This report presents a case of mental nerve paresthesia caused by endodontic infection of a mandibular left second premolar. Resolution of the paresthesia began two weeks after conventional root canal treatment associated with antibiotic therapy and was completed in eight weeks. One year follow-up radiograph indicated complete healing of the radiolucent periapical lesion. The tooth was asymptomatic and functional. PMID:26345692

Interventional Management for Pelvic Pain.

PubMed

Nagpal, Ameet S; Moody, Erika L

2017-08-01

Interventional procedures can be applied for diagnostic evaluation and treatment of the patient with pelvic pain, often once more conservative measures have failed to provide relief. This article reviews interventional management strategies for pelvic pain. We review superior and inferior hypogastric plexus blocks, ganglion impar blocks, transversus abdominis plane blocks, ilioinguinal, iliohypogastric and genitofemoral blocks, pudendal nerve blocks, and selective nerve root blocks. Additionally, we discuss trigger point injections, sacroiliac joint injections, and neuromodulation approaches. Copyright © 2017 Elsevier Inc. All rights reserved.

Heisenberg limit for displacements with semiclassical states

NASA Astrophysics Data System (ADS)

Luis, Alfredo

2004-04-01

We analyze the quantum limit to the sensitivity of the detection of small displacements. We focus on the case of free particles and harmonic oscillators as the systems experiencing the displacement. We show that the minimum displacement detectable is proportional to the inverse of the square root of the mean value of the energy in the state experiencing the displacement (Heisenberg limit). We present a measuring scheme that reaches this limit using semiclassical states. We examine the performance of this strategy under realistic practical conditions by computing the effect of imperfections such as losses and nonunit detection efficiencies. This analysis confirms the robustness of this measuring strategy by showing that the experimental imperfections can be suitably compensated by increasing the mean energy of the input state.

Characterization of in vitro transcriptional responses of dorsal root ganglia cultured in the presence and absence of blastema cells from regenerating salamander limbs

PubMed Central

Athippozhy, Antony; Lehrberg, Jeffrey; Monaghan, James R.; Gardiner, David M.

2014-01-01

Abstract During salamander limb regeneration, nerves provide signals that induce the formation of a mass of proliferative cells called the blastema. To better understand these signals, we developed a blastema−dorsal root ganglia (DRG) co‐culture model system to test the hypothesis that nerves differentially express genes in response to cues provided by the blastema. DRG with proximal and distal nerve trunks were isolated from axolotls (Ambystoma mexicanum), cultured for 5 days, and subjected to microarray analysis. Relative to freshly isolated DRG, 1541 Affymetrix probe sets were identified as differentially expressed and many of the predicted genes are known to function in injury and neurodevelopmental responses observed for mammalian DRG. We then cultured 5‐day DRG explants for an additional 5 days with or without co‐cultured blastema cells. On day 10, we identified 27 genes whose expression in cultured DRG was significantly affected by the presence or absence of blastema cells. Overall, our study established a DRG−blastema in vitro culture system and identified candidate genes for future investigations of axon regrowth, nerve−blastema signaling, and neural regulation of limb regeneration. PMID:25750744

The sympathetic hazards of airborne ultrasound on ultrasound sensitive mice.

PubMed

Ohmori, M; Ogawa, K

1982-01-01

A commercially available ultrasonic equipment (55-50 kHz/sec, 425 W) operated at a distance of 4 m air space caused death in some mice. The physical energy propagated was quite small, being calculated at less than 0.21 W/cm2. Among many strains of mice, the RIII strain was especially sensitive to ultrasound, and the peak of sensitivity was at 3 to 4 weeks of age at which the mortality rate was 95/149 (64%). No death occurred when mice were pretreated by (a) removing all body hair, (b) by administration of morphine hydrochloridum with a tail reaction, and (c) administration of a sympathetic blocking agent. From these results it is assumed that the ultrasound energy absorbed by the body fur reaches the hypothalamus through the sensory nerves of the hair roots. After the hypothalamus where central sympathetic nerve functions are localized, the stimulus passes down the descending tract of the sympathetic nerve, reaching the cardiac nerves via the autonomic nerve ganglion. Thus, death could occur by shock of the sympathetic nerve reflex.

On the nature of the afferent fibers of oculomotor nerve.

PubMed

Manni, E; Draicchio, F; Pettorossi, V E; Carobi, C; Grassi, S; Bortolami, R; Lucchi, M L

1989-03-01

The oculogyric nerves contain afferent fibers originating from the ophthalmic territory, the somata of which are located in the ipsilateral semilunar ganglion. These primary sensory neurons project to the Subnucleus Gelatinosus of the Nucleus Caudalis Trigemini, where they make presynaptic contact with the central endings of the primary trigeminal afferents running in the fifth cranial nerve. After complete section of the trigeminal root, the antidromic volleys elicited in the trunk of the third cranial nerve by stimulating SG of NCT consisted of two waves belonging to the A delta and C groups. The area of both components of the antidromic volleys decreased both after bradykinin and hystamine injection into the corresponding cutaneous region and after thermic stimulation of the ipsilateral trigeminal ophthalmic territory. The reduction of such potentials can be explained in terms of collision between the antidromic volleys and those elicited orthodromically by chemical and thermic stimulation. Also, capsaicin applied on the nerve induced an immediate increase, followed by a long lasting decrease, of orthodromic evoked response area. These findings bring further support to the nociceptive nature of the afferent fibers running into the oculomotor nerve.

Rehabilitation of the trigeminal nerve

PubMed Central

Iro, Heinrich; Bumm, Klaus; Waldfahrer, Frank

2005-01-01

When it comes to restoring impaired neural function by means of surgical reconstruction, sensory nerves have always been in the role of the neglected child when compared with motor nerves. Especially in the head and neck area, with its either sensory, motor or mixed cranial nerves, an impaired sensory function can cause severe medical conditions. When performing surgery in the head and neck area, sustaining neural function must not only be highest priority for motor but also for sensory nerves. In cases with obvious neural damage to sensory nerves, an immediate neural repair, if necessary with neural interposition grafts, is desirable. Also in cases with traumatic trigeminal damage, an immediate neural repair ought to be considered, especially since reconstructive measures at a later time mostly require for interposition grafts. In terms of the trigeminal neuralgia, commonly thought to arise from neurovascular brainstem compression, a pharmaceutical treatment is considered as the state of the art in terms of conservative therapy. A neurovascular decompression of the trigeminal root can be an alternative in some cases when surgical treatment is sought after. Besides the above mentioned therapeutic options, alternative treatments are available. PMID:22073060

Multitrophic effects of calcium availability on invasive alien plants, birds, and bird prey items

Treesearch

Vince D' Amico; Greg Shriver; Jake Bowman; Meg Ballard; Whitney Wiest; Liz Tymkiw; Melissa Miller

2011-01-01

Acid rain alters forest soil calcium concentrations in two ways: (1) hydrogen ions displace exchangeable calcium adsorbed to soil surfaces, and (2) aluminum is released to soil water by acid rain and displaces adsorbed calcium. This increases the absorption of aluminum by plant roots, and decreases the absorption of calcium, causing calcium to be more readily leached...

Novel drug delivering conduit for peripheral nerve regeneration

NASA Astrophysics Data System (ADS)

Labroo, Pratima; Shea, Jill; Edwards, Kyle; Ho, Scott; Davis, Brett; Sant, Himanshu; Goodwin, Isak; Gale, Bruce; Agarwal, Jay

2017-12-01

Objective. This paper describes the design of a novel drug delivery apparatus integrated with a poly lactic-co-glycolic acid (PLGA) based nerve guide conduit for controlled local delivery of nerve growth factor (NGF) and application in peripheral nerve gap injury. Approach. An NGF dosage curve was acquired to determine the minimum in vitro concentration for optimal neurite outgrowth of dorsal root ganglion (DRG) cells; PLGA based drug delivery devices were then designed and tested in vitro and in vivo across 15 mm rat sciatic nerve gap injury model. Main results. The drug delivery nerve guide was able to release NGF for 28 d at concentrations (0.1-10 ng ml-1) that were shown to enhance DRG neurite growth. Furthermore, the released NGF was bioactive and able to enhance DRG neurite growth. Following these tests, optimized NGF-releasing nerve conduits were implanted across 15 mm sciatic nerve gaps in a rat model, where they demonstrated significant myelination and muscle innervation in vivo as compared to empty nerve conduits (p  <  0.05). This drug delivery nerve guide can release NGF for extended periods of time and enhance axon growth in vitro and in vivo and has the potential to improve nerve regeneration following a peripheral nerve injury. Significance. This integrated drug delivering nerve guide simplifies the design process and provides increased versatility for releasing a variety of different growth factors. This innovative device has the potential for broad applicability and allows for easier customization to change the type of drugs and dosage of individual drugs without devising a completely new biomaterial-drug conjugate each time.

Intramuscular Distribution of the Abducens Nerve in the Lateral Rectus Muscle for the Management of Strabismus.

PubMed

Shin, Hyun Jin; Lee, Shin-Hyo; Shin, Kang-Jae; Koh, Ki-Seok; Song, Wu-Chul

2018-06-01

To elucidate the intramuscular distribution and branching patterns of the abducens nerve in the lateral rectus (LR) muscle so as to provide anatomical confirmation of the presence of compartmentalization, including for use in clinical applications such as botulinum toxin injections. Thirty whole-mount human cadaver specimens were dissected and then Sihler's stain was applied. The basic dimensions of the LR and its intramuscular nerve distribution were investigated. The distances from the muscle insertion to the point at which the abducens nerve enters the LR and to the terminal nerve plexus were also measured. The LR was 46.0 mm long. The abducens nerve enters the muscle on the posterior one-third of the LR and then typically divides into a few branches (average of 1.8). This supports a segregated abducens nerve selectively innervating compartments of the LR. The intramuscular nerve distribution showed a Y-shaped ramification with root-like arborization. The intramuscular nerve course finished around the middle of the LR (24.8 mm posterior to the insertion point) to form the terminal nerve plexus. This region should be considered the optimal target site for botulinum toxin injections. We have also identified the presence of an overlapping zone and communicating nerve branches between the neighboring LR compartments. Sihler's staining is a useful technique for visualizing the entire nerve network of the LR. Improving the knowledge of the nerve distribution patterns is important not only for researchers but also clinicians to understand the functions of the LR and the diverse pathophysiology of strabismus.

An update-tissue engineered nerve grafts for the repair of peripheral nerve injuries.

PubMed

Patel, Nitesh P; Lyon, Kristopher A; Huang, Jason H

2018-05-01

Peripheral nerve injuries (PNI) are caused by a range of etiologies and result in a broad spectrum of disability. While nerve autografts are the current gold standard for the reconstruction of extensive nerve damage, the limited supply of autologous nerve and complications associated with harvesting nerve from a second surgical site has driven groups from multiple disciplines, including biomedical engineering, neurosurgery, plastic surgery, and orthopedic surgery, to develop a suitable or superior alternative to autografting. Over the last couple of decades, various types of scaffolds, such as acellular nerve grafts (ANGs), nerve guidance conduits, and non-nervous tissues, have been filled with Schwann cells, stem cells, and/or neurotrophic factors to develop tissue engineered nerve grafts (TENGs). Although these have shown promising effects on peripheral nerve regeneration in experimental models, the autograft has remained the gold standard for large nerve gaps. This review provides a discussion of recent advances in the development of TENGs and their efficacy in experimental models. Specifically, TENGs have been enhanced via incorporation of genetically engineered cells, methods to improve stem cell survival and differentiation, optimized delivery of neurotrophic factors via drug delivery systems (DDS), co-administration of platelet-rich plasma (PRP), and pretreatment with chondroitinase ABC (Ch-ABC). Other notable advancements include conduits that have been bioengineered to mimic native nerve structure via cell-derived extracellular matrix (ECM) deposition, and the development of transplantable living nervous tissue constructs from rat and human dorsal root ganglia (DRG) neurons. Grafts composed of non-nervous tissues, such as vein, artery, and muscle, will be briefly discussed.

Intracranial distribution of the sympathetic system in mice: DiI tracing and immunocytochemical labeling

NASA Technical Reports Server (NTRS)

Maklad, A.; Quinn, T.; Fritzsch, B.

2001-01-01

The intracranial distribution of the cephalic branches of the superior cervical ganglion (scg) was studied in mice using indocarbocyanine dye (DiI) anterograde tracing. Two main branches were traced from the scg. The first branch joined the nerve of the pterygoid canal (the vidian nerve), npc, from which several intracranial sympathetic branches passed to the branches of the trigeminal nerve (tgn), abducent nerve (abn), trochlear nerve (trn), and oculomotor nerve (ocn). Most of the second branch joined the abn, from which sympathetic fibers dispersed in the distal region of the trigeminal ganglion (tgg) to form a plexus close to the ganglion's branches. Branches from this plexus joined the branches of the tgn, trn, and ocn. Several minor branches arising from the second branch of the scg were also observed. One formed a sympathetic plexus around the internal carotid artery (ica); a second formed a sympathetic plexus in the proximal region of tgg, close to its root; and a third branch coursed laterally to reach the ear by passing along the greater petrosal nerve (gpn). All of the intracranial trajectories traced from scg were found to be catecholaminergic, and likely sympathetic, using tyrosine hydroxylase (TH) immunocytochemistry.

Comparative study of phrenic and intercostal nerve transfers for elbow flexion after global brachial plexus injury.

PubMed

Liu, Yuzhou; Lao, Jie; Zhao, Xin

2015-04-01

Global brachial plexus injuries (BPIs) are devastating events frequently resulting in severe functional impairment. The widely used nerve transfer sources for elbow flexion in patients with global BPIs include intercostal and phrenic nerves. The aim of this study was to compare phrenic and intercostal nerve transfers for elbow flexion after global BPI. A retrospective review of 33 patients treated with phrenic and intercostal nerve transfer for elbow flexion in posttraumatic global root avulsion BPI was carried out. In the phrenic nerve transfer group, the phrenic nerve was transferred to the anterolateral bundle of the anterior division of the upper trunk (23 patients); in the intercostal nerve transfer group, three intercostal nerves were coapted to the anterolateral bundles of the musculocutaneous nerve. The British Medical Research Council (MRC) grading system, angle of elbow flexion, and electromyography (EMG) were used to evaluate the recovery of elbow flexion at least 3 years postoperatively. The efficiency of motor function in the phrenic nerve transfer group was 83%, while it was 70% in the intercostal nerve transfer group. The two groups were not statistically different in terms of the MRC grade (p=0.646) and EMG results (p=0.646). The outstanding rates of angle of elbow flexion were 48% and 40% in the phrenic and intercostal nerve transfer groups, respectively. There was no significant difference of outstanding rates in the angle of elbow flexion between the two groups. Phrenic nerve transfer had a higher proportion of good prognosis for elbow flexion than intercostal nerve transfer, but the effective and outstanding rate had no significant difference for biceps reinnervation between the two groups according to MRC grading, angle of elbow flexion, and EMG. Copyright © 2014 Elsevier Ltd. All rights reserved.

Brainstem abnormalities and vestibular nerve enhancement in acute neuroborreliosis.

PubMed

Farshad-Amacker, Nadja A; Scheffel, Hans; Frauenfelder, Thomas; Alkadhi, Hatem

2013-12-21

Borreliosis is a widely distributed disease. Neuroborreliosis may present with unspecific symptoms and signs and often remains difficult to diagnose in patients with central nervous system symptoms, particularly if the pathognomonic erythema chronica migrans does not develop or is missed. Thus, vigilance is mandatory in cases with atypical presentation of the disease and with potentially severe consequences if not recognized early. We present a patient with neuroborreliosis demonstrating brain stem and vestibular nerve abnormalities on magnetic resonance imaging. A 28-year-old Caucasian female presented with headaches, neck stiffness, weight loss, nausea, tremor, and gait disturbance. Magnetic resonance imaging showed T2-weighted hyperintense signal alterations in the pons and in the vestibular nerves as well as bilateral post-contrast enhancement of the vestibular nerves. Serologic testing of the cerebrospinal fluid revealed the diagnosis of neuroborreliosis. Patients infected with neuroborreliosis may present with unspecific neurologic symptoms and magnetic resonance imaging as a noninvasive imaging tool showing signal abnormalities in the brain stem and nerve root enhancement may help in establishing the diagnosis.

Peripheral choline acetyltransferase in rat skin demonstrated by immunohistochemistry.

PubMed

Hanada, Keiji; Kishimoto, Saburo; Bellier, Jean-Pierre; Kimura, Hiroshi

2013-03-01

Conventional choline acetyltransferase immunohistochemistry has been used widely for visualizing central cholinergic neurons and fibers but not often for labeling peripheral structures, probably because of their poor staining. The recent identification of the peripheral type of choline acetyltransferase (pChAT) has enabled the clear immunohistochemical detection of many known peripheral cholinergic elements. Here, we report the presence of pChAT-immunoreactive nerve fibers in rat skin. Intensely stained nerve fibers were distributed in association with eccrine sweat glands, blood vessels, hair follicles and portions just beneath the epidermis. These results suggest that pChAT-positive nerves participate in the sympathetic cholinergic innervation of eccrine sweat glands. Moreover, pChAT also appears to play a role in cutaneous sensory nerve endings. These findings are supported by the presence of many pChAT-positive neuronal cells in the sympathetic ganglion and dorsal root ganglion. Thus, pChAT immunohistochemistry should provide a novel and unique tool for studying cholinergic nerves in the skin.

DNA methyltransferase DNMT3a contributes to neuropathic pain by repressing Kcna2 in primary afferent neurons

PubMed Central

Zhao, Jian-Yuan; Liang, Lingli; Gu, Xiyao; Li, Zhisong; Wu, Shaogen; Sun, Linlin; Atianjoh, Fidelis E.; Feng, Jian; Mo, Kai; Jia, Shushan; Lutz, Brianna Marie; Bekker, Alex; Nestler, Eric J.; Tao, Yuan-Xiang

2017-01-01

Nerve injury induces changes in gene transcription in dorsal root ganglion (DRG) neurons, which may contribute to nerve injury-induced neuropathic pain. DNA methylation represses gene expression. Here, we report that peripheral nerve injury increases expression of the DNA methyltransferase DNMT3a in the injured DRG neurons via the activation of the transcription factor octamer transcription factor 1. Blocking this increase prevents nerve injury-induced methylation of the voltage-dependent potassium (Kv) channel subunit Kcna2 promoter region and rescues Kcna2 expression in the injured DRG and attenuates neuropathic pain. Conversely, in the absence of nerve injury, mimicking this increase reduces the Kcna2 promoter activity, diminishes Kcna2 expression, decreases Kv current, increases excitability in DRG neurons and leads to spinal cord central sensitization and neuropathic pain symptoms. These findings suggest that DNMT3a may contribute to neuropathic pain by repressing Kcna2 expression in the DRG. PMID:28270689

Comparative anatomy of the accessory ciliary ganglion in mammals.

PubMed

Kuchiiwa, S; Kuchiiwa, T; Suzuki, T

1989-01-01

The orbits of 13 mammalian species (pig, sika deer, domestic sheep, horse, cat, fox, racoon dog, marten, rat, rabbit, crab-eating macaque, japanese macaque and man) were stained with silver nitrate and dissected under a dissecting microscope with special attention to the presence and location of the accessory ciliary ganglion. Some preparations were stained with thionin and examined as whole-mounts in a transmission microscope. The accessory ciliary ganglion was present in all 13 species, although the number and degree of development varied greatly from species to species. The accessory ciliary ganglion could be readily differentiated from the main ciliary ganglion in the following respects: it was located on the short ciliary nerve, and it had no root derived directly from the inferior trunk of the oculomotor nerve and it never attaches to this nerve. In many species, ganglion cells were also scattered in the short ciliary nerves in the stained whole preparations. In a few species, there were one or more small ganglia on the nerve to the inferior oblique muscle.

The neurotrophic effects of different human dental mesenchymal stem cells.

PubMed

Kolar, Mallappa K; Itte, Vinay N; Kingham, Paul J; Novikov, Lev N; Wiberg, Mikael; Kelk, Peyman

2017-10-03

The current gold standard treatment for peripheral nerve injury is nerve grafting but this has disadvantages such as donor site morbidity. New techniques focus on replacing these grafts with nerve conduits enhanced with growth factors and/or various cell types such as mesenchymal stem cells (MSCs). Dental-MSCs (D-MSCs) including stem cells obtained from apical papilla (SCAP), dental pulp stem cells (DPSC), and periodontal ligament stem cells (PDLSC) are potential sources of MSCs for nerve repair. Here we present the characterization of various D-MSCs from the same human donors for peripheral nerve regeneration. SCAP, DPSC and PDLSC expressed BDNF, GDNF, NGF, NTF3, ANGPT1 and VEGFA growth factor transcripts. Conditioned media from D-MSCs enhanced neurite outgrowth in an in vitro assay. Application of neutralizing antibodies showed that brain derived neurotrophic factor plays an important mechanistic role by which the D-MSCs stimulate neurite outgrowth. SCAP, DPSC and PDLSC were used to treat a 10 mm nerve gap defect in a rat sciatic nerve injury model. All the stem cell types significantly enhanced axon regeneration after two weeks and showed neuroprotective effects on the dorsal root ganglia neurons. Overall the results suggested SCAP to be the optimal dental stem cell type for peripheral nerve repair.

Hericium erinaceus (Bull.: Fr.) Pers., a medicinal mushroom, activates peripheral nerve regeneration.

PubMed

Wong, Kah-Hui; Kanagasabapathy, Gowri; Naidu, Murali; David, Pamela; Sabaratnam, Vikineswary

2016-10-01

To study the ability of aqueous extract of Hericium erinaceus mushroom in the treatment of nerve injury following peroneal nerve crush in Sprague-Dawley rats. Aqueous extract of Hericium erinaceus was given by daily oral administration following peroneal nerve crush injury in Sprague-Dawley rats. The expression of protein kinase B (Akt) and mitogen-activated protein kinase (MAPK) signaling pathways; and c-Jun and c-Fos genes were studied in dorsal root ganglia (DRG) whereas the activity of protein synthesis was assessed in peroneal nerves by immunohistochemical method. Peripheral nerve injury leads to changes at the axonal site of injury and remotely located DRG containing cell bodies of sensory afferent neurons. Immunofluorescence studies showed that DRG neurons ipsilateral to the crush injury in rats of treated groups expressed higher immunoreactivities for Akt, MAPK, c-Jun and c-Fos as compared with negative control group (P <0.05). The intensity of nuclear ribonucleoprotein in the distal segments of crushed nerves of treated groups was significantly higher than in the negative control group (P <0.05). H. erinaceus is capable of promoting peripheral nerve regeneration after injury. Potential signaling pathways include Akt, MAPK, c-Jun, and c-Fos, and protein synthesis have been shown to be involved in its action.

Myelography

MedlinePlus

... and the injection of contrast material in the space around the spinal cord and nerve roots (the subarachnoid space ) using a real-time form of x-ray ... the contrast material is injected into the subarachnoid space, the radiologist is able to view and evaluate ...

Hereditary sensory ataxic neuropathy associated with proximal muscle weakness in the lower extremities.

PubMed

Murakami, Tatsufumi; Fukai, Yuta; Rikimaru, Mitsue; Henmi, Shoji; Ohsawa, Yutaka; Sunada, Yoshihide

2010-04-15

We describe three patients from the same family with hereditary sensory ataxic neuropathy followed by proximal muscle weakness in the lower extremities. Sensory ataxic gait began as an initial symptom when patients were in their 50s. Mild proximal weakness in the lower extremities appeared several years later. Serum creatine kinase was mildly elevated. Nerve conduction studies revealed sensory dominant axonal neuropathy, and short sensory evoked potentials showed involvement of the sensory nerve axon, dorsal root ganglia and posterior funiculus of the spinal cord. Needle electromyography showed fibrillation, positive sharp waves, and multiple giant motor unit potentials, suggesting the involvement of anterior horn motor neurons or the anterior root. Autosomal recessive inheritance was considered, because of consanguinity. The disorder described here may be a new clinical entity with unique clinical manifestations. Copyright 2009 Elsevier B.V. All rights reserved.

Neuroprotective Drug for Nerve Trauma Revealed Using Artificial Intelligence.

PubMed

Romeo-Guitart, David; Forés, Joaquim; Herrando-Grabulosa, Mireia; Valls, Raquel; Leiva-Rodríguez, Tatiana; Galea, Elena; González-Pérez, Francisco; Navarro, Xavier; Petegnief, Valerie; Bosch, Assumpció; Coma, Mireia; Mas, José Manuel; Casas, Caty

2018-01-30

Here we used a systems biology approach and artificial intelligence to identify a neuroprotective agent for the treatment of peripheral nerve root avulsion. Based on accumulated knowledge of the neurodegenerative and neuroprotective processes that occur in motoneurons after root avulsion, we built up protein networks and converted them into mathematical models. Unbiased proteomic data from our preclinical models were used for machine learning algorithms and for restrictions to be imposed on mathematical solutions. Solutions allowed us to identify combinations of repurposed drugs as potential neuroprotective agents and we validated them in our preclinical models. The best one, NeuroHeal, neuroprotected motoneurons, exerted anti-inflammatory properties and promoted functional locomotor recovery. NeuroHeal endorsed the activation of Sirtuin 1, which was essential for its neuroprotective effect. These results support the value of network-centric approaches for drug discovery and demonstrate the efficacy of NeuroHeal as adjuvant treatment with surgical repair for nervous system trauma.

Herpes zoster - typical and atypical presentations.

PubMed

Dayan, Roy Rafael; Peleg, Roni

2017-08-01

Varicella- zoster virus infection is an intriguing medical entity that involves many medical specialties including infectious diseases, immunology, dermatology, and neurology. It can affect patients from early childhood to old age. Its treatment requires expertise in pain management and psychological support. While varicella is caused by acute viremia, herpes zoster occurs after the dormant viral infection, involving the cranial nerve or sensory root ganglia, is re-activated and spreads orthodromically from the ganglion, via the sensory nerve root, to the innervated target tissue (skin, cornea, auditory canal, etc.). Typically, a single dermatome is involved, although two or three adjacent dermatomes may be affected. The lesions usually do not cross the midline. Herpes zoster can also present with unique or atypical clinical manifestations, such as glioma, zoster sine herpete and bilateral herpes zoster, which can be a challenging diagnosis even for experienced physicians. We discuss the epidemiology, pathophysiology, diagnosis and management of Herpes Zoster, typical and atypical presentations.

Minimally invasive palliative resection of lumbar epidural metastasis.

PubMed

Yew, Andrew; Kimball, Jon; Pezeshkian, Patrick; Lu, Daniel C

2013-07-01

Spinal metastatic lesions are the most common tumors encountered by spinal surgeons. As with procedures for degenerative disease, minimally invsive surgery techniques have been applied to minimize muscle and soft tissue destruction in procedures for tumor resection. Here, we present a 23-year-old female with radiculopathy and foot drop secondary to nerve root compression by epidural metastases from Ewing's sarcoma. This patient had a history of previous resection and instrumentation as well as multiple rounds of chemotherapy and radiation that failed to control her disease. The patient presented with three weeks of radicular pain and foot drop that was continuing to worsen at the time of her operation. The decision was therefore made to perform a palliative resection and decompression for relief of her progressive symptoms. In this video, we demonstrate a palliative tumor debulking and nerve root decompression utilizing an MIS approach. The video can be found here: http://youtu.be/tq4kbvKTebI.

Different types of spinal afferent nerve endings in stomach and esophagus identified by anterograde tracing from dorsal root ganglia.

PubMed

Spencer, Nick J; Kyloh, Melinda; Beckett, Elizabeth A; Brookes, Simon; Hibberd, Tim

2016-10-15

In visceral organs of mammals, most noxious (painful) stimuli as well as innocuous stimuli are detected by spinal afferent neurons, whose cell bodies lie in dorsal root ganglia (DRGs). One of the major unresolved questions is the location, morphology, and neurochemistry of the nerve endings of spinal afferents that actually detect these stimuli in the viscera. In the upper gastrointestinal (GI) tract, there have been many anterograde tracing studies of vagal afferent endings, but none on spinal afferent endings. Recently, we developed a technique that now provides selective labeling of only spinal afferents. We used this approach to identify spinal afferent nerve endings in the upper GI tract of mice. Animals were anesthetized, and injections of dextran-amine were made into thoracic DRGs (T8-T12). Seven days post surgery, mice were euthanized, and the stomach and esophagus were removed, fixed, and stained for calcitonin gene-related peptide (CGRP). Spinal afferent axons were identified that ramified extensively through many rows of myenteric ganglia and formed nerve endings in discrete anatomical layers. Most commonly, intraganglionic varicose endings (IGVEs) were identified in myenteric ganglia of the stomach and varicose simple-type endings in the circular muscle and mucosa. Less commonly, nerve endings were identified in internodal strands, blood vessels, submucosal ganglia, and longitudinal muscle. In the esophagus, only IGVEs were identified in myenteric ganglia. No intraganglionic lamellar endings (IGLEs) were identified in the stomach or esophagus. We present the first identification of spinal afferent endings in the upper GI tract. Eight distinct types of spinal afferent endings were identified in the stomach, and most of them were CGRP immunoreactive. J. Comp. Neurol. 524:3064-3083, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Distinct degree of radiculopathy at different levels of peripheral nerve injury

PubMed Central

2012-01-01

Background Lumbar radiculopathy is a common clinical problem, characterized by dorsal root ganglion (DRG) injury and neural hyperactivity causing intense pain. However, the mechanisms involved in DRG injury have not been fully elucidated. Furthermore, little is known about the degree of radiculopathy at the various levels of nerve injury. The purpose of this study is to compare the degree of radiculopathy injury at the DRG and radiculopathy injury proximal or distal to the DRG. Results The lumbar radiculopathy rat model was created by ligating the L5 nerve root 2 mm proximal to the DRG or 2 mm distal to the DRG with 6.0 silk. We examined the degree of the radiculopathy using different points of mechanical sensitivity, immunohistochemistry and in vivo patch-clamp recordings, 7 days after surgery. The rats injured distal to the DRG were more sensitive than those rats injured proximal to the DRG in the behavioral study. The number of activated microglia in laminas I–II of the L5 segmental level was significantly increased in rats injured distal to the DRG when compared with rats injured proximal to the DRG. The amplitudes and frequencies of EPSC in the rats injured distal to the DRG were higher than those injured proximal to the DRG. The results indicated that there is a different degree of radiculopathy at the distal level of nerve injury. Conclusions Our study examined the degree of radiculopathy at different levels of nerve injury. Severe radiculopathy occurred in rats injured distal to the DRG when compared with rats injured proximal to the DRG. This finding helps to correctly diagnose a radiculopathy. PMID:22537715

Population calcium imaging of spontaneous respiratory and novel motor activity in the facial nucleus and ventral brainstem in newborn mice

PubMed Central

Persson, Karin; Rekling, Jens C

2011-01-01

Abstract The brainstem contains rhythm and pattern forming circuits, which drive cranial and spinal motor pools to produce respiratory and other motor patterns. Here we used calcium imaging combined with nerve recordings in newborn mice to reveal spontaneous population activity in the ventral brainstem and in the facial nucleus. In Fluo-8 AM loaded brainstem–spinal cord preparations, respiratory activity on cervical nerves was synchronized with calcium signals at the ventrolateral brainstem surface. Individual ventrolateral neurons at the level of the parafacial respiratory group showed perfect or partial synchrony with respiratory nerve bursts. In brainstem–spinal cord preparations, cut at the level of the mid-facial nucleus, calcium signals were recorded in the dorsal, lateral and medial facial subnuclei during respiratory activity. Strong activity initiated in the dorsal subnucleus, followed by activity in lateral and medial subnuclei. Whole-cell recordings from facial motoneurons showed weak respiratory drives, and electrical field potential recordings confirmed respiratory drive to particularly the dorsal and lateral subnuclei. Putative facial premotoneurons showed respiratory-related calcium signals, and were predominantly located dorsomedial to the facial nucleus. A novel motor activity on facial, cervical and thoracic nerves was synchronized with calcium signals at the ventromedial brainstem extending from the level of the facial nucleus to the medulla–spinal cord border. Cervical dorsal root stimulation induced similar ventromedial activity. The medial facial subnucleus showed calcium signals synchronized with this novel motor activity on cervical nerves, and cervical dorsal root stimulation induced similar medial facial subnucleus activity. In conclusion, the dorsal and lateral facial subnuclei are strongly respiratory-modulated, and the brainstem contains a novel pattern forming circuit that drives the medial facial subnucleus and cervical motor pools. PMID:21486812

Cervical extraforaminal ligaments: an anatomical study.

PubMed

Arslan, Mehmet; Açar, Halil İbrahim; Cömert, Ayhan

2017-12-01

The purpose of this study was to elucidate the anatomy and clinical importance of extraforaminal ligaments in the cervical region. This study was performed on eight embalmed cadavers. The existence and types of extraforaminal ligaments were identified. The morphology, quantity, origin, insertion, and orientation of the extraforaminal ligaments in the cervical region were observed. Extraforaminal ligaments could be divided into two types: transforaminal ligaments and radiating ligaments. It was observed that during their course, transforaminal ligaments cross the intervertebral foramen ventrally. They usually originate from the anteroinferior margin of the anterior tubercle of the cranial transverse process and insert into the superior margin of the anterior tubercle of the caudal transverse process. The dorsal aspect of the transforaminal ligaments adhere loosely to the spinal nerve sheath. The length, width and thickness of these ligaments increased from the cranial to the caudal direction. A single intervertebral foramen contained at least one transforaminal ligament. A total of 98 ligaments in 96 intervertebral foramina were found. The spinal nerves were extraforaminally attached to neighboring anterior and posterior tubercle of the cervical transverse process by the radiating ligaments. The radiating ligaments consisted of the ventral superior, ventral, ventral inferior, dorsal superior and dorsal inferior radiating ligaments. Radiating ligaments originated from the adjacent transverse processes and inserted into the nerve root sheath. The spinal nerve was held like the hub of a wheel by a series of radiating ligaments. The dorsal ligaments were the thickest. From C2-3 to C6-7 at the cervical spine, radiating ligaments were observed. They developed particularly at the level of the C5-C6 intervertebral foramen. This anatomic study may provide a better understanding of the relationship of the extraforaminal ligaments to the cervical nerve root.

[Expression and significance of p75NTR in dorsal root ganglia in different injury models].

PubMed

Li, Fang; Cai, Yan; Zhang, Jian-Yi

2008-12-01

To determine the expression and significance of p75NTR in the neuron and glia of dorsal root ganglia (DRG) in different injury models. The models of sciatic nerve injury, spinal cord injury, and combined injury (sciatic nerve injury one week prior to spinal cord injury) were established. The rats were randomly divided into a normal group,a sciatic nerve injury group,a spinal cord injury group, and a combined injury group. The sensory neurons in the DRG were labeled by fast blue (FB) injected in the dorsal column of spinal cord 0.5mm rostral to the transection site. The expression of p75NTR in the neurons and glia of the DRG was examined with immunofluorescence histochemistry after different kinds of injury and its expression in the FB positive neurons was further observed with immunofluorescence histochemistry combined with FB retrograde labeling. The expression of p75NTR was increased in the glia, but was downregulated in sensory neurons in the sciatic nerve injury group compared with the normal group. p75NTR immunoreactive products were downregulated in the glia in the spinal cord injury group compared with the sciatic nerve injury group or the combined injury group. In the combined lesion animals, the expression of p75NTR was similar to that of the sciatic nerve injury group. Its expression in the sensory neurons of DRG was downregulated,but was upregulated in the glia. The majority of sensory neurons labeled by FB in the combined injury group were p75NTR-negative, but surrounded by p75NTR-positive glia. p75NTR immunoreactive products in the glia and neurons of DRG have significant discrepancy after injury. The glial p75NTR in the DRG may play a role in the enhanced regeneration of acsending tract in the injured spinal cord after combined injury.

The distribution and origin of a novel brain peptide, neuropeptide Y, in the spinal cord of several mammals.

PubMed

Gibson, S J; Polak, J M; Allen, J M; Adrian, T E; Kelly, J S; Bloom, S R

1984-07-20

The distribution of neuropeptide Y [NPY]-immunoreactive material was examined in the spinal cord and dorsal root ganglia of rat, guinea-pig, cat, marmoset, and horse. Considerable concentrations of NPY and similar distribution patterns of immunoreactive nerve fibres were found in the spinal cord of all species investigated. The dorsal root ganglia of the cat and the horse contained numerous immunoreactive nerve fibres, but in these species, as in the other three studied [rat, guinea-pig, marmoset], no positively stained cell bodies were found. Neuropeptide Y-immunoreactive nerves were observed at all levels of the spinal cord, being most concentrated in the dorsal horn. In the rat, guinea-pig, and marmoset, there was a marked increase of NPY-immunoreactive fibres in the lumbosacral regions of the spinal cord, and this was reflected by a considerable increase of extractable NPY. Estimations of NPY-immunoreactive material in the various regions of the rat spinal cord were as follows: cervical, 13.8 +/- 1.0; thoracic, 21.1 +/- 2.5; lumbar, 16.3 +/- 2.9; sacral, 92.4 +/- 8.5 pmol/gm wet weight of tissue +/- SEM. In the ventral portion of the guinea-pig spinal cord they were as follows: cervical, 7.1 +/- 1.2; thoracic, 8.2 +/- 3.6; lumbar, 22.6 +/- 7.0; sacral, 36.7 +/- 9.5 pmol/gm wet weight of tissue +/- SEM. Analysis of spinal cord extracts by reverse phase high performance liquid chromatography [HPLC] demonstrated that NPY-immunoreactive material elutes in the position of pure NPY standard. No changes in the concentration and distribution of the NPY-like material in the rat spinal cord were observed following a variety of surgical and pharmacological manipulations, including cervical rhizotomy, sciatic nerve section and ligation, and local application of capsaicin [50 mM] to one sciatic nerve. It is therefore suggested that most of the NPY-immunoreactive material in the spinal cord is derived either from intrinsic nerve cell bodies or from supraspinal tracts.

Axillary nerve monitoring during arthroscopic shoulder stabilization.

PubMed

Esmail, Adil N; Getz, Charles L; Schwartz, Daniel M; Wierzbowski, Lawrence; Ramsey, Matthew L; Williams, Gerald R

2005-06-01

This study evaluated the ability of a novel intraoperative neurophysiologic monitoring method used to locate the axillary nerve, predict relative capsule thickness, and identify impending injury to the axillary nerve during arthroscopic thermal capsulorrhaphy of the shoulder. Prospective cohort study. Twenty consecutive patients with glenohumeral instability were monitored prospectively during arthroscopic shoulder surgery. Axillary nerve mapping and relative capsule thickness estimates were recorded before the stabilization portion of the procedure. During labral repair and/or thermal capsulorrhaphy, continuous and spontaneous electromyography recorded nerve activity. In addition, trans-spinal motor-evoked potentials of the fourth and fifth cervical roots and brachial plexus electrical stimulation, provided real-time information about nerve integrity. Axillary nerve mapping and relative capsule thickness were recorded in all patients. Continuous axillary nerve monitoring was successfully performed in all patients. Eleven of the 20 patients underwent thermal capsulorrhaphy alone or in combination with arthroscopic labral repair. Nine patients underwent arthroscopic labral repair alone. In 4 of the 11 patients who underwent thermal capsulorrhaphy, excessive spontaneous neurotonic electromyographic activity was noted, thereby altering the pattern of heat application by the surgeon. In 1 of these 4 patients, a small increase in the motor latency was noted after the procedure but no clinical deficit was observed. There were no neuromonitoring or clinical neurologic changes observed in the labral repair group without thermal application. At last follow-up, no patient in either group had any clinical evidence of nerve injury or complications from neurophysiologic monitoring. We successfully evaluated the use of intraoperative nerve monitoring to identify axillary nerve position, capsule thickness, and provide real-time identification of impending nerve injury and function during shoulder thermal capsulorrhaphy. The use of intraoperative nerve monitoring altered the heat application technique in 4 of 11 patients and may have prevented nerve injury. Level II, prospective cohort study.

Effects of exogenous galanin on neuropathic pain state and change of galanin and its receptors in DRG and SDH after sciatic nerve-pinch injury in rat.

PubMed

Xu, Xiaofeng; Yang, Xiangdong; Zhang, Ping; Chen, Xiuying; Liu, Huaxiang; Li, Zhenzhong

2012-01-01

A large number of neuroanatomical, neurophysiologic, and neurochemical mechanisms are thought to contribute to the development and maintenance of neuropathic pain. However, mechanisms responsible for neuropathic pain have not been completely delineated. It has been demonstrated that neuropeptide galanin (Gal) is upregulated after injury in the dorsal root ganglion (DRG) and spinal dorsal horn (SDH) where it plays a predominantly antinociceptive role. In the present study, sciatic nerve-pinch injury rat model was used to determine the effects of exogenous Gal on the expression of the Gal and its receptors (GalR1, GalR2) in DRG and SDH, the alterations of pain behavior, nerve conduction velocity (NCV) and morphology of sciatic nerve. The results showed that exogenous Gal had antinociceptive effects in this nerve-pinch injury induced neuropathic pain animal model. It is very interesting that Gal, GalR1 and GalR2 change their expression greatly in DRG and SDH after nerve injury and intrathecal injection of exougenous Gal. Morphological investigation displays a serious damage after nerve-pinch injury and an amendatory regeneration after exogenous Gal treatment. These findings imply that Gal, via activation of GalR1 and/or GalR2, may have neuroprotective effects in reducing neuropathic pain behaviors and improving nerve regeneration after nerve injury.

Arterial relationships to the nerves and some rigid structures in the posterior cranial fossa.

PubMed

Surchev, N

2008-09-01

The close relationships between the cranial nerves and the arterial vessels in the posterior cranial fossa are one of the predisposing factors for artery-nerve compression. The aim of this study was to examine the relationships of the vertebral and basilar arteries to some skull and dural structures and the nerves in the posterior cranial fossa. For this purpose, the skull bases and brains of 70 cadavers were studied. The topographic relationships of the vertebral and basilar arteries to the cranial nerves in the posterior cranial fossa were studied and the distances between the arteries and some osseous formations were measured. The most significant variations in arterial position were registered in the lower half of the basilar artery. Direct contact with an artery was established for the hypoglossal canal, jugular tubercle, and jugular foramen. The results reveal additional information about the relationships of the nerves and arteries to the skull and dural formations in the posterior cranial fossa. New quantitative information is given to illustrate them. The conditions for possible artery-nerve compression due to arterial dislocation are discussed and two groups (lines) of compression points are suggested. The medial line comprises of the brain stem points, usually the nerve root entry/exit zone. The lateral line includes the skull eminences, on which the nerves lie, or skull and dural foramina through which they exit the cranial cavity. (c) 2008 Wiley-Liss, Inc.

Neuroprotective effects of (-)-epigallocatechin-3-gallate (EGCG) against peripheral nerve transection-induced apoptosis.

PubMed

Kian, Kosar; Khalatbary, Ali Reza; Ahmadvand, Hassan; Karimpour Malekshah, Abbasali; Shams, Zahra

2018-01-02

Recent studies revealed the neuroprotective effects of epigallocatechin-3-gallate (EGCG) on a variety of neural injury models. The purpose of this study was to determine the neuroprotective effects of EGCG following sciatic nerve transection (SNT). Rats were randomly divided into four groups each as follows: Sham-operated group, SNT group, and Pre-EGCG (50-mg/kg, i.p., 30 minutes before nerve transection and followed for 3 days) and Post-EGCG (50-mg/kg, i.p., 1 hour after nerve transection and followed for 3 days) groups. Spinal cord segments of the sciatic nerve and related dorsal root ganglions were removed four weeks after nerve transection for the assessment of malondialdehyde (MDA) levels, superoxide dismutase (SOD) and catalase (CAT) activities, immunohistochemistry of caspase-3, cyclooxygenase-2 (COX-2), S100beta (S100B), and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL). MDA levels were significantly decreased, and SOD and CAT activities were significantly increased in EGCG-treated rats after nerve transection. Attenuated caspase-3 and COX-2 expression, and TUNEL reaction could be significantly detected in the EGCG-treated rats after nerve transection. Also, EGCG significantly increased S100B expression. We propose that EGCG may be effective in the protection of neuronal cells against retrograde apoptosis and may enhance neuronal survival time following nerve transection.

Ultrasound assessment of peripheral nerve pathology in neurofibromatosis type 1 and 2.

PubMed

Winter, Natalie; Rattay, Tim W; Axer, Hubertus; Schäffer, Eva; Décard, Bernhard F; Gugel, Isabel; Schuhmann, Martin; Grimm, Alexander

2017-05-01

The neurofibromatoses (NF) type 1 and 2 are hereditary tumor predisposition syndromes caused by germline mutations in the NF1 and NF2 tumor suppressor genes. In NF1 and 2, peripheral nerve tumors occur regularly. For further characterizing nerve ultrasound was performed in patients with NF1 and 2. Patients with established diagnosis of NF1 (n=27) and NF2 (n=10) were included. Ultrasound of peripheral nerves and cervical roots was performed during routine follow-up visits. Healthy volunteers were studied for comparison. In patients with NF1, median cross-sectional area (CSA) of most nerves was significantly increased compared to controls and to NF2 due to generalized plexiform tumors, which arose out of multiple fascicles in 23 of 27 patients (85%). These were often accompanied by cutaneous or subcutaneous neurofibromas. In NF2, the overall aspect of peripheral nerves consisted of localized schwannomas (80%) and, apart from that, normal nerve segments. Nerve ultrasound is able to visualize different nerve pathologies in NF1 and NF2. It is a precise and inexpensive screening method for peripheral nerve manifestation in neurofibromatosis and should be considered as the first choice screening imaging modality for all peripheral nerves within reach of non-invasive ultrasound techniques. Ultrasound patterns of peripheral nerve pathologies are described for the first time in a large cohort of patients with NF1 and NF2. It is a suitable screening tool and enables targeted MRI analysis. Copyright © 2017 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

The double crush syndrome revisited--a Delphi study to reveal current expert views on mechanisms underlying dual nerve disorders.

PubMed

Schmid, Annina B; Coppieters, Michel W

2011-12-01

A high prevalence of dual nerve disorders is frequently reported. How a secondary nerve disorder may develop following a primary nerve disorder remains largely unknown. Although still frequently cited, most explanatory theories were formulated many years ago. Considering recent advances in neuroscience, it is uncertain whether these theories still reflect current expert opinion. A Delphi study was conducted to update views on potential mechanisms underlying dual nerve disorders. In three rounds, seventeen international experts in the field of peripheral nerve disorders were asked to list possible mechanisms and rate their plausibility. Mechanisms with a median plausibility rating of ≥7 out of 10 were considered highly plausible. The experts identified fourteen mechanisms associated with a first nerve disorder that may predispose to the development of another nerve disorder. Of these fourteen mechanisms, nine have not previously been linked to double crush. Four mechanisms were considered highly plausible (impaired axonal transport, ion channel up or downregulation, inflammation in the dorsal root ganglia and neuroma-in-continuity). Eight additional mechanisms were listed which are not triggered by a primary nerve disorder, but may render the nervous system more vulnerable to multiple nerve disorders, such as systemic diseases and neurotoxic medication. Even though many mechanisms were classified as plausible or highly plausible, overall plausibility ratings varied widely. Experts indicated that a wide range of mechanisms has to be considered to better understand dual nerve disorders. Previously listed theories cannot be discarded, but may be insufficient to explain the high prevalence of dual nerve disorders. Copyright © 2011 Elsevier Ltd. All rights reserved.

Complications of fluoroscopically directed facet joint nerve blocks: a prospective evaluation of 7,500 episodes with 43,000 nerve blocks.

PubMed

Manchikanti, Laxmaiah; Malla, Yogesh; Wargo, Bradley W; Cash, Kimberly A; Pampati, Vidyasagar; Fellows, Bert

2012-01-01

Chronic spinal pain is common along with numerous modalities of diagnostic and therapeutic interventions utilized, creating a health care crisis. Facet joint injections and epidural injections are the 2 most commonly utilized interventions in managing chronic spinal pain. While the literature addressing the effectiveness of facet joint nerve blocks is variable and emerging, there is paucity of literature on adverse effects of facet joint nerve blocks. A prospective, non-randomized study of patients undergoing interventional techniques from May 2008 to December 2009. A private interventional pain management practice, a specialty referral center in the United States. Investigation of the incidence in characteristics of adverse effects and complications of facet joint nerve blocks. The study was carried out over a period of 20 months including almost 7,500 episodes of 43,000 facet joint nerve blocks with 3,370 episodes in the cervical region, 3,162 in the lumbar region, and 950 in the thoracic region. All facet joint nerve blocks were performed under fluoroscopic guidance in an ambulatory surgery center by 3 physicians. The complications encountered during the procedure and postoperatively were evaluated prospectively. This study was carried out over a period of 20 months and included over 7,500 episodes or 43,000 facet joint nerve blocks. All of the interventions were performed under fluoroscopic guidance in an ambulatory surgery center by one of 3 physicians. The complications encountered during the procedure and postoperatively were prospectively evaluated. Measurable outcomes employed were intravascular entry of the needle, profuse bleeding, local hematoma, dural puncture and headache, nerve root or spinal cord irritation with resultant injury, and infectious complications. There were no major complications. Multiple side effects and complications observed included overall intravascular penetration in 11.4% of episodes with 20% in cervical region, 4% in lumbar region, and 6% in thoracic region; local bleeding in 76.3% of episodes with highest in thoracic region and lowest in cervical region; oozing with 19.6% encounters with highest in cervical region and lowest in lumbar region; with local hematoma seen only in 1.2% of the patients with profuse bleeding, bruising, soreness, nerve root irritation, and all other effects such as vasovagal reactions observed in 1% or less of the episodes. Limitations of this study include lack of contrast injection, use of intermittent fluoroscopy and also an observational nature of the study. This study illustrate that major complications are extremely rare and minor side effects are common.

Long-term outcomes of intradural cervical dorsal root rhizotomy for refractory occipital neuralgia.

PubMed

Gande, Abhiram V; Chivukula, Srinivas; Moossy, John J; Rothfus, William; Agarwal, Vikas; Horowitz, Michael B; Gardner, Paul A

2016-07-01

OBJECT Occipital neuralgia (ON) causes chronic pain in the cutaneous distribution of the greater and lesser occipital nerves. The long-term efficacy of cervical dorsal root rhizotomy (CDR) in the management of ON has not been well described. The authors reviewed their 14-year experience with CDR to assess pain relief and functional outcomes in patients with medically refractory ON. METHODS A retrospective chart review of 75 ON patients who underwent cervical dorsal root rhizotomy, from 1998 to 2012, was performed. Fifty-five patients were included because they met the International Headache Society's (IHS) diagnostic criteria for ON, responded to CT-guided nerve blocks at the C-2 dorsal nerve root, and had at least one follow-up visit. Telephone interviews were additionally used to obtain data on patient satisfaction. RESULTS Forty-two patients (76%) were female, and the average age at surgery was 46 years (range 16-80). Average follow up was 67 months (range 5-150). Etiologies of ON included the following: idiopathic (44%), posttraumatic (27%), postsurgical (22%), post-cerebrovascular accident (4%), postherpetic (2%), and postviral (2%). At last follow-up, 35 patients (64%) reported full pain relief, 11 (20%) partial relief, and 7 (16%) no pain relief. The extent of pain relief after CDR was not significantly associated with ON etiology (p = 0.43). Of 37 patients whose satisfaction-related data were obtained, 25 (68%) reported willingness to undergo repeat surgery for similar pain relief, while 11 (30%) reported no such willingness; a single patient (2%) did not answer this question. Twenty-one individuals (57%) reported that their activity level/functional state improved after surgery, 5 (13%) reported a decline, and 11 (30%) reported no difference. The most common acute postoperative complications were infections in 9% (n = 5) and CSF leaks in 5% (n = 3); chronic complications included neck pain/stiffness in 16% (n = 9) and upper-extremity symptoms in 5% (n = 3) such as trapezius weakness, shoulder pain, and arm paresthesias. CONCLUSIONS Cervical dorsal root rhizotomy provides an efficacious means for pain relief in patients with medically refractory ON. In the appropriately selected patient, it may lead to optimal outcomes with a relatively low risk of complications.

Prevention of neurological injuries during mandibular third molar surgery: technical notes

PubMed Central

La Monaca, Gerardo; Vozza, Iole; Giardino, Rita; Annibali, Susanna; Pranno, Nicola; Cristalli, Maria Paola

2017-01-01

Summary Surgery to the mandibular third molar is common, and injuries to the inferior alveolar nerve and the lingual nerve are well-recognized complications of this procedure. The aim of these technical notes is to describe operative measures for reducing neurological complications during mandibular third molar surgery. The following procedure should be used to prevent damage to the inferior alveolar nerve: a well-designed mucoperiosteal flap, to obtain appropriate access to the surgical area; a conservative ostectomy on the distal and distal-lingual side; tooth sectioning, to facilitate its removal by decreasing the retention zones; tooth dislocation in the path of withdrawal imposed by the curvature of the root apex; and careful socket debridement, when the roots of the extracted tooth are in intimate contact with the mandibular canal. To prevent injury to the lingual nerve, it is important (I) to assess the integrity of the mandibular inner cortex and exclude the presence of fenestration, which could cause the dislocation of the tooth or its fragment into the sublingual or submandibular space; (II) to avoid inappropriate or excessive dislocation proceedings, in order to prevent lingual cortex fracture; (III) to perform horizontal mesial-distal crown sectioning of the lingually inclined tooth; (IV) to protect the lingual flap with a retractor showing the cortical ridge; and (V) to pass the suture not too apically and from the inner side in a buccal-lingual direction in the retromolar area. PMID:29299188

Postoperative occipital neuralgia in posterior upper cervical spine surgery: a systematic review.

PubMed

Guan, Qing; Xing, Fei; Long, Ye; Xiang, Zhou

2017-11-07

Postoperative occipital neuralgia (PON) after upper cervical spine surgery can cause significant morbidity and may be overlooked. The causes, presentation, diagnosis, management, prognosis, and prevention of PON were reviewed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. English-language studies and case reports published from inception to 2017 were retrieved. Data on surgical procedures, incidence, cause of PON, management, outcomes, and preventive technique were extracted. Sixteen articles, including 591 patients, were selected; 93% of the patients with PON underwent C1 lateral mass screw (C1LMS) fixation, with additional 7% who underwent occipitocervical fusion without C1 fixation. PON had an incidence that ranged from 1 to 35% and was transient in 34%, but persistent in 66%. Five articles explained the possible causes. The primary presentation was constant or paroxysmal burning pain located mainly in the occipital and upper neck area and partially extending to the vertical, retroauricular, retromandibular, and forehead zone. Treatment included medications, nerve block, revision surgery, and nerve stimulation. Two prospective studies compared the effect of C2 nerve root transection on PON. PON in upper cervical spine surgery is a debilitating complication and was most commonly encountered by patients undergoing C1LMS fixation. The etiology of PON is partially clear, and the pain could be persistent and hard to cure. Reducing the incidence of PON can be realized by improving technique. More high-quality prospective studies are needed to define the effect of C2 nerve root transection on PON.

Pressure wave injuries to rat dorsal root ganglion cells in culture caused by high-energy missiles.

PubMed

Suneson, A; Hansson, H A; Lycke, E; Seeman, T

1989-01-01

A high-energy missile impact in an extremity of an animal creates a shock wave which is rapidly dispersed as a burst of oscillating pressure waves that traverses the entire body causing local, regional, and distant injuries. The present study was performed on dorsal root ganglion (DRG) cells, cultured for 3 weeks, to elucidate the cellular mechanism for damage of nerve cells, using a simplified test system. A model system was developed allowing exposure of DRG cultures to a burst of high-frequency oscillating pressure waves, comparable to those recorded in animals after high-energy missile extremity impact. The pressure waves were induced by impact of a high-energy missile in a rubber tube filled with water, in which nerve cell cultures were kept in a closed rubber glove filled with tissue culture medium. The pressure waves had a duration of 0.5-1.5 ms and a frequency spectrum ranging from 0-250 kHz. Within minutes the neurites showed changes in their microtubules. In addition, varicosities, enriched with tubulin immunoreactive material, became irregularly studded along the nerve cell processes. Scattered DRG cells were initially permeable to the marker complex Evans-blue albumin (EBA), used as an indicator of the ability of the plasma membranes to exclude proteins. After 6 hr, however, almost every DRG neuron was intensely stained by EBA. Concomitantly, there was swelling of the nerve cell cytoplasm and organelles, and, to a variable extent, neurofilament tangles were observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Slump Test: Effect of Contralateral Knee Extension on Response Sensations in Asymptomatic Subjects and Cadaver Study.

PubMed

Shacklock, Michael; Yee, Brian; Van Hoof, Tom; Foley, Russ; Boddie, Keith; Lacey, Erin; Poley, J Bryan; Rade, Marinko; Kankaanpää, Markku; Kröger, Heikki; Airaksinen, Olavi

2016-02-01

Part 1: A randomized, single-blind study on the effect of contralateral knee extension on sensations produced by the slump test (ST) in asymptomatic subjects. Part 2: A cadaver study simulating the nerve root behavior of part 1. Part 1: Test if contralateral knee extension consistently reduces normal stretch sensations with the ST.Part 2: Ascertain in cadavers an explanation for the results. In asymptomatic subjects, contralateral knee extension reduces stretch sensations with the ST. In sciatica patients, contralateral SLR also can temporarily reduce sciatica. We studied this methodically in asymptomatic subjects before considering a clinical population. Part 1: Sixty-one asymptomatic subjects were tested in control (ST), sham, or intervention (contralateral ST) groups and their sensation response intensity compared.Part 2: Caudal tension was applied to the L5 nerve root of 3 cadavers and tension behavior of the contralateral neural tissue recorded visually. Part 1: Reduction of stretch sensations occurred in the intervention group but not in control and sham groups (P ≤ 0.001).Part 2: Tension in the contralateral lumbar nerve roots and dura reduced in a manner consistent with the responses in the intervention (contralateral ST) group. Part 1: In asymptomatic subjects, normal thigh stretch sensations with the ST reduced consistently with the contralateral ST, showing that this is normal and may now be compared with patients with sciatica.Part 2: Contralateral reduction in lumbar neural tension with unilateral application of tension-producing movements also occurred in cadavers, supporting the proposed explanatory hypothesis.

Displacement of mandibular fractures: is there a correlation with sensory loss and recovery?

PubMed

Scott, R A; Teo, N; Perry, M

2014-05-01

Fractures of the mandible are common. However, the correlation between the severity of the fracture and the recovery of any associated inferior dental (ID) nerve injury is still poorly understood. We aimed to examine the relationship between the amount of fracture displacement and how it relates to the recovery of sensation to the lower lip. One hundred and fifty patients requiring treatment of a mandibular fracture (where the fracture passed across the ID canal) were assessed. One hundred were initially assessed in a retrospective double-blinded study. A further 50 patients were then followed up prospectively. Both the maximal displacement of the fracture and the displacement specifically at the ID canal were measured. Sensory recovery, or persistence of numbness, was also recorded for each patient. Although there appeared to be a correlation between increasing displacement at the ID canal and a poorer recovery, there was not a clear relationship between the two, and there were many exceptions. Persistent numbness (>1 year) still occurred in fractures with relatively minimal displacement (≤3mm). Possible reasons for persistent numbness are discussed. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

Morphology and Nanomechanics of Sensory Neurons Growth Cones following Peripheral Nerve Injury

PubMed Central

Szabo, Vivien; Végh, Attila-Gergely; Lucas, Olivier; Cloitre, Thierry; Scamps, Frédérique; Gergely, Csilla

2013-01-01

A prior peripheral nerve injury in vivo, promotes a rapid elongated mode of sensory neurons neurite regrowth in vitro. This in vitro model of conditioned axotomy allows analysis of the cellular and molecular mechanisms leading to an improved neurite re-growth. Our differential interference contrast microscopy and immunocytochemistry results show that conditioned axotomy, induced by sciatic nerve injury, did not increase somatic size of adult lumbar sensory neurons from mice dorsal root ganglia sensory neurons but promoted the appearance of larger neurites and growth cones. Using atomic force microscopy on live neurons, we investigated whether membrane mechanical properties of growth cones of axotomized neurons were modified following sciatic nerve injury. Our data revealed that neurons having a regenerative growth were characterized by softer growth cones, compared to control neurons. The increase of the growth cone membrane elasticity suggests a modification in the ratio and the inner framework of the main structural proteins. PMID:23418549

Myelinated sensory and alpha motor axon regeneration in peripheral nerve neuromas

NASA Technical Reports Server (NTRS)

Macias, M. Y.; Lehman, C. T.; Sanger, J. R.; Riley, D. A.

1998-01-01

Histochemical staining for carbonic anhydrase and cholinesterase (CE) activities was used to analyze sensory and motor axon regeneration, respectively, during neuroma formation in transected and tube-encapsulated peripheral nerves. Median-ulnar and sciatic nerves in the rodent model permitted testing whether a 4 cm greater distance of the motor neuron soma from axotomy site or intrinsic differences between motor and sensory neurons influenced regeneration and neuroma formation 10, 30, and 90 days later. Ventral root radiculotomy confirmed that CE-stained axons were 97% alpha motor axons. Distance significantly delayed axon regeneration. When distance was negligible, sensory axons grew out sooner than motor axons, but motor axons regenerated to a greater quantity. These results indicate regeneration differences between axon subtypes and suggest more extensive branching of motor axons within the neuroma. Thus, both distance from injury site to soma and inherent motor and sensory differences should be considered in peripheral nerve repair strategies.

Identification of PN1, a Predominant Voltage-Dependent Sodium Channel Expressed Principally in Peripheral Neurons

NASA Astrophysics Data System (ADS)

Toledo-Aral, Juan J.; Moss, Brenda L.; He, Zhi-Jun; Koszowski, Adam G.; Whisenand, Teri; Levinson, Simon R.; Wolf, John J.; Silos-Santiago, Inmaculada; Halegoua, Simon; Mandel, Gail

1997-02-01

Membrane excitability in different tissues is due, in large part, to the selective expression of distinct genes encoding the voltage-dependent sodium channel. Although the predominant sodium channels in brain, skeletal muscle, and cardiac muscle have been identified, the major sodium channel types responsible for excitability within the peripheral nervous system have remained elusive. We now describe the deduced primary structure of a sodium channel, peripheral nerve type 1 (PN1), which is expressed at high levels throughout the peripheral nervous system and is targeted to nerve terminals of cultured dorsal root ganglion neurons. Studies using cultured PC12 cells indicate that both expression and targeting of PN1 is induced by treatment of the cells with nerve growth factor. The preferential localization suggests that the PN1 sodium channel plays a specific role in nerve excitability.

Histochemical discrimination of fibers in regenerating rat infraorbital nerve

NASA Technical Reports Server (NTRS)

Wilke, R. A.; Riley, D. A.; Sanger, J. R.

1992-01-01

In rat dorsal root ganglia, histochemical staining of carbonic anhydrase (CA) and cholinesterase (CE) yields a reciprocal pattern of activity: Sensory processes are CA positive and CE negative, whereas motor processes are CA negative and CE positive. In rat infraorbital nerve (a sensory peripheral nerve), we saw extensive CA staining of nearly 100% of the myelinated axons. Although CE reactivity in myelinated axons was extremely rare, we did observe CE staining of unmyelinated autonomic fibers. Four weeks after transection of infraorbital nerves, CA-stained longitudinal sections of the proximal stump demonstrated 3 distinct morphological zones. A fraction of the viable axons retained CA activity to within 2 mm of the distal extent of the stump, and the stain is capable of resolving growth sprouts being regenerated from these fibers. Staining of unmyelinated autonomic fibers in serial sections shows that CE activity was not retained as far distally as is the CA sensory staining.

Assessment of nerve involvement in the lumbar spine: agreement between magnetic resonance imaging, physical examination and pain drawing findings.

PubMed

Bertilson, Bo C; Brosjö, Eva; Billing, Hans; Strender, Lars-Erik

2010-09-10

Detection of nerve involvement originating in the spine is a primary concern in the assessment of spine symptoms. Magnetic resonance imaging (MRI) has become the diagnostic method of choice for this detection. However, the agreement between MRI and other diagnostic methods for detecting nerve involvement has not been fully evaluated. The aim of this diagnostic study was to evaluate the agreement between nerve involvement visible in MRI and findings of nerve involvement detected in a structured physical examination and a simplified pain drawing. Sixty-one consecutive patients referred for MRI of the lumbar spine were - without knowledge of MRI findings - assessed for nerve involvement with a simplified pain drawing and a structured physical examination. Agreement between findings was calculated as overall agreement, the p value for McNemar's exact test, specificity, sensitivity, and positive and negative predictive values. MRI-visible nerve involvement was significantly less common than, and showed weak agreement with, physical examination and pain drawing findings of nerve involvement in corresponding body segments. In spine segment L4-5, where most findings of nerve involvement were detected, the mean sensitivity of MRI-visible nerve involvement to a positive neurological test in the physical examination ranged from 16-37%. The mean specificity of MRI-visible nerve involvement in the same segment ranged from 61-77%. Positive and negative predictive values of MRI-visible nerve involvement in segment L4-5 ranged from 22-78% and 28-56% respectively. In patients with long-standing nerve root symptoms referred for lumbar MRI, MRI-visible nerve involvement significantly underestimates the presence of nerve involvement detected by a physical examination and a pain drawing. A structured physical examination and a simplified pain drawing may reveal that many patients with "MRI-invisible" lumbar symptoms need treatment aimed at nerve involvement. Factors other than present MRI-visible nerve involvement may be responsible for findings of nerve involvement in the physical examination and the pain drawing.

Nonmonotonic fluctuation spectra of membranes pinned or tethered discretely to a substrate.

PubMed

Merath, Rolf-Jürgen; Seifert, Udo

2006-01-01

The thermal fluctuation spectrum of a fluid membrane coupled harmonically to a solid support by an array of tethers is calculated. For strong tethers, this spectrum exhibits nonmonotonic, anisotropic behavior with a relative maximum at a wavelength about twice the tether distance. The root-mean-square displacement is evaluated to estimate typical membrane displacements. Possible applications cover pillar-supported or polymer-tethered membranes.

The effects of Transcutaneous Electrical Nerve Stimulation on postural control in patients with chronic low back pain.

PubMed

Rojhani-Shirazi, Z; Rezaeian, T

2015-01-01

Objective: The effects of transcutaneous electrical nerve stimulation (TENS) on postural control in patients with low back pain which is not well known. This study aimed to evaluate the effects of TENS on postural control in chronic low back pain. Methods: This study was an experimental research design. Twenty-eight patients with chronic LBP (25-45 Y/ O) participated and by using a random allocation, were divided to samples who participated in this study. The mean center of pressure (COP) velocity and displacement were measured before, immediately and 30 min after the intervention. The tests were done with eyes open and closed on a force platform. Sensory electrical stimulation was applied through the TENS device. The descriptive statistics, independent sample T-test and ANOVA with repeated measurement on time were used for data analysis. Results: The results of the present study demonstrated that the application of the sensory electrical stimulation in chronic LBP patients showed a statistically significant improvement in postural control in Medio-lateral direction with no corresponding effect on the anterior-posterior direction immediately following the TENS application and 30 minutes after it in closed eyes conditions as compared to baseline. The application of TENS decreased the displacement and velocity of COP (p≤0.05), 30 minutes after the application of sensory electrical stimulation. The results showed that the mean displacement and velocity of COP decreased in eyes open position (p≤0.05). Also, immediately and 30 minutes after the application of sensory electrical stimulation, COP displacement and velocity in ML direction with eyes closed significantly decreased in the intervention group in comparison with control group (p≤0.05). Conclusion: The application of TENS in patients with chronic low back pain could improve postural control in these patients.

The effects of Transcutaneous Electrical Nerve Stimulation on postural control in patients with chronic low back pain

PubMed Central

Rojhani-Shirazi, Z; Rezaeian, T

2015-01-01

Objective: The effects of transcutaneous electrical nerve stimulation (TENS) on postural control in patients with low back pain which is not well known. This study aimed to evaluate the effects of TENS on postural control in chronic low back pain. Methods: This study was an experimental research design. Twenty-eight patients with chronic LBP (25-45 Y/ O) participated and by using a random allocation, were divided to samples who participated in this study. The mean center of pressure (COP) velocity and displacement were measured before, immediately and 30 min after the intervention. The tests were done with eyes open and closed on a force platform. Sensory electrical stimulation was applied through the TENS device. The descriptive statistics, independent sample T-test and ANOVA with repeated measurement on time were used for data analysis. Results: The results of the present study demonstrated that the application of the sensory electrical stimulation in chronic LBP patients showed a statistically significant improvement in postural control in Medio-lateral direction with no corresponding effect on the anterior-posterior direction immediately following the TENS application and 30 minutes after it in closed eyes conditions as compared to baseline. The application of TENS decreased the displacement and velocity of COP (p≤0.05), 30 minutes after the application of sensory electrical stimulation. The results showed that the mean displacement and velocity of COP decreased in eyes open position (p≤0.05). Also, immediately and 30 minutes after the application of sensory electrical stimulation, COP displacement and velocity in ML direction with eyes closed significantly decreased in the intervention group in comparison with control group (p≤0.05). Conclusion: The application of TENS in patients with chronic low back pain could improve postural control in these patients. PMID:28255392

Late administration of high-frequency electrical stimulation increases nerve regeneration without aggravating neuropathic pain in a nerve crush injury.

PubMed

Su, Hong-Lin; Chiang, Chien-Yi; Lu, Zong-Han; Cheng, Fu-Chou; Chen, Chun-Jung; Sheu, Meei-Ling; Sheehan, Jason; Pan, Hung-Chuan

2018-06-25

High-frequency transcutaneous neuromuscular electrical nerve stimulation (TENS) is currently used for the administration of electrical current in denervated muscle to alleviate muscle atrophy and enhance motor function; however, the time window (i.e. either immediate or delayed) for achieving benefit is still undetermined. In this study, we conducted an intervention of sciatic nerve crush injury using high-frequency TENS at different time points to assess the effect of motor and sensory functional recovery. Animals with left sciatic nerve crush injury received TENS treatment starting immediately after injury or 1 week later at a high frequency(100 Hz) or at a low frequency (2 Hz) as a control. In SFI gait analysis, either immediate or late admission of high-frequency electrical stimulation exerted significant improvement compared to either immediate or late administration of low-frequency electrical stimulation. In an assessment of allodynia, immediate high frequency electrical stimulation caused a significantly decreased pain threshold compared to late high-frequency or low-frequency stimulation at immediate or late time points. Immunohistochemistry staining and western blot analysis of S-100 and NF-200 demonstrated that both immediate and late high frequency electrical stimulation showed a similar effect; however the effect was superior to that achieved with low frequency stimulation. Immediate high frequency electrical stimulation resulted in significant expression of TNF-α and synaptophysin in the dorsal root ganglion, somatosensory cortex, and hippocampus compared to late electrical stimulation, and this trend paralleled the observed effect on somatosensory evoked potential. The CatWalk gait analysis also showed that immediate electrical stimulation led to a significantly high regularity index. In primary dorsal root ganglion cells culture, high-frequency electrical stimulation also exerted a significant increase in expression of TNF-α, synaptophysin, and NGF in accordance with the in vivo results. Immediate or late transcutaneous high-frequency electrical stimulation exhibited the potential to stimulate the motor nerve regeneration. However, immediate electrical stimulation had a predilection to develop neuropathic pain. A delay in TENS initiation appears to be a reasonable approach for nerve repair and provides the appropriate time profile for its clinical application.

Biomechanical comparison between suture anchor and transtibial pull-out repair for posterior medial meniscus root tears.

PubMed

Feucht, Matthias J; Grande, Eduardo; Brunhuber, Johannes; Rosenstiel, Nikolaus; Burgkart, Rainer; Imhoff, Andreas B; Braun, Sepp

2014-01-01

Posterior medial meniscus root (PMMR) tears have a serious effect on knee joint biomechanics. Currently used techniques for refixation of the PMMR include the transtibial pull-out repair (TP) and suture anchor repair (SA). These techniques have not been compared biomechanically. The SA technique provides superior biomechanical properties compared with the TP technique. Controlled laboratory study. A total of 24 fresh-frozen porcine tibiae with attached intact medial menisci were used. The specimens were randomly assigned to 3 groups (8 specimens each). A standardized PMMR tear was created in 16 specimens. Refixation of the PMMR was performed by either the TP or SA technique. The native PMMR was left intact in 8 specimens. All specimens were subjected to cyclic loading followed by load-to-failure testing. Displacement after 100, 500, and 1000 cycles; maximum load to failure; stiffness; and displacement at failure were recorded. Both repair techniques showed a significantly higher displacement during cyclic loading and a significantly lower maximum load and stiffness during load-to-failure testing compared with the native PMMR (P < .05). The SA technique showed a significantly lower displacement after 100, 500, and 1000 cycles (P < .001) and a significantly higher stiffness (P = .016) compared with the TP technique. Maximum load did not differ significantly between the SA and TP techniques (P = .027, Bonferroni adjustment). No significant difference between the 3 groups was observed for displacement at failure (P > .05). The SA technique provided superior biomechanical properties compared with the TP technique. Both repair techniques did not reach the strength of the native PMMR. The favorable biomechanical properties of the SA technique might be beneficial for healing of the repaired PMMR and restoration of meniscus function. Because of inferior time zero stability compared with the native PMMR, slow rehabilitation is recommended after meniscus root repair.

Retrospective review of the efficacy and safety of repeated pulsed and continuous radiofrequency lesioning of the dorsal root ganglion/segmental nerve for lumbar radicular pain.

PubMed

Nagda, Jyotsna V; Davis, Craig W; Bajwa, Zahid H; Simopoulos, Thomas T

2011-01-01

Chronic lumbosacral radicular pain is a common source of radiating leg pain seen in pain management patients. These patients are frequently managed conservatively with multiple modalities including medications, physical therapy, and epidural steroid injections. Radiofrequency has been used to treat chronic radicular pain for over 30 years; however, there is a paucity of literature about the safety and efficacy of repeat radiofrequency lesioning. To determine the safety, success rate, and duration of pain relief of repeat pulsed radiofrequency (PRF) and continuous radiofrequency (CRF) lesioning of the dorsal root ganglion (DRG)/ sacral segmental nerves (SN) in patients with chronic lumbosacral radicular pain. Retrospective chart review Outpatient multidisciplinary pain center Medical record review of patients who were treated with pulsed and continuous radiofrequency lesioning of the lumbar dorsal root ganglia and segmental nerves and who reported initial success were evaluated for recurrence of pain and repeat radiofrequency treatment. Responses to subsequent treatments were compared to initial treatments for success rates, average duration of relief, and adverse neurologic side-effects. Retrospective chart review without a control group. Twenty-six women and 24 men were identified who received 50% pain relief or better after PRF and CRF of the lumbar DRG/ sacral SN for lumbosacral radicular pain. The mean age was 62 years (range, 25-86). The mean duration of relief for the 40 patients who had 2 treatments was 4.7 months (range 0-24; Se [standard error] 0.74). Twenty-eight patients had 3 treatments with an average duration of relief of 4.5 months (range 0-19 months; Se 0.74). Twenty patients had 4 treatments with a mean duration of relief of 4.4 months (range 0.5-18; Se 0.95) and 18 patients who had 5 or more treatments received an average duration of relief of 4.3 months (range 0.5-18; Se 1.03). The average duration of relief and success frequency remained constant after each subsequent radiofrequency treatment. Of the 50 total patients, there was only 1 reported complication, specifically, transient thigh numbness which resolved after one week. Repeated pulsed and continuous radiofrequency ablation of the lumbar dorsal root ganglion/segmental nerve shows promise to be a safe and effective long-term palliative management for lumbosacral radicular pain in some patients.

Does the presence of the nerve root sedimentation sign on MRI correlate with the operative level in patients undergoing posterior lumbar decompression for lumbar stenosis?

PubMed

Fazal, Akil; Yoo, Andrew; Bendo, John A

2013-08-01

Recent research describes the use of a nerve root sedimentation sign to diagnose lumbar spinal stenosis (LSS). The lack of sedimentation of the nerve roots (positive sedimentation sign) to the dorsal part of the dural sac is the characteristic feature of this new radiological parameter. To demonstrate how the nerve root sedimentation sign compares with other more traditional radiological parameters in patients who have been operated for LSS. A retrospective chart and image review. Preoperative magnetic resonance images (MRIs) were reviewed from 71 consecutive operative patients who presented with LSS and received spinal decompression surgery from 2006 to 2010. Preoperative T2-weighted MRIs were reviewed for each patient. One hundred thirty-four vertebral levels from L1 to L5 were measured for: sedimentation sign, cross-sectional area (CSA) and anterior/posterior (A/P) diameter of the dural sac, thickness of the ligamentum flavum, and Fujiwara grade of facet hypertrophy. Radiological measurements were made using Surgimap 1.1.2.169 software (Nemaris, Inc., New York, NY, USA). Statistical analyses were performed using the SPSS 17.0 statistical software (SPSS Inc., Chicago, IL, USA). Significance was demonstrated using unpaired t tests and chi-squared tests. Study funding was departmental. There were no study-specific conflicts of interest-associated biases. A positive sedimentation sign was determined in 120 operated levels (89.5%), whereas 14 levels (10.5%) had no sign (negative sedimentation sign). The mean CSA and A/P diameter were 140.62 mm(2) (standard deviation [SD]=53) and 11.76 mm (SD=3), respectively, for the no-sign group; the mean CSA and A/P diameter were 81.87 mm(2) (SD=35) and 8.76 mm (SD=2.2), respectively, for the sedimentation sign group (p<.001). We found that 60% of levels with Fujiwara Grade A facet hypertrophy did not have a sedimentation sign, whereas 86.3% of levels with Grade B, 93.2% of levels with Grade C, and 100.0% of levels with Grade D did have a sedimentation sign (p<.001). The sedimentation sign is a new measurement tool that can enable physicians to objectively assess and quantify spinal stenosis. The sign is most often present in patients who have clinically significant lumbar stenosis and require surgery. Copyright © 2013 Elsevier Inc. All rights reserved.

Inflammation in the Pathogenesis of Lyme Neuroborreliosis

PubMed Central

Ramesh, Geeta; Didier, Peter J.; England, John D.; Santana-Gould, Lenay; Doyle-Meyers, Lara A.; Martin, Dale S.; Jacobs, Mary B.; Philipp, Mario T.

2016-01-01

Lyme neuroborreliosis, caused by the spirochete Borrelia burgdorferi, affects both peripheral and central nervous systems. We assessed a causal role for inflammation in Lyme neuroborreliosis pathogenesis by evaluating the induced inflammatory changes in the central nervous system, spinal nerves, and dorsal root ganglia (DRG) of rhesus macaques that were inoculated intrathecally with live B. burgdorferi and either treated with dexamethasone or meloxicam (anti-inflammatory drugs) or left untreated. ELISA of cerebrospinal fluid showed significantly elevated levels of IL-6, IL-8, chemokine ligand 2, and CXCL13 and pleocytosis in all infected animals, except dexamethasone-treated animals. Cerebrospinal fluid and central nervous system tissues of infected animals were culture positive for B. burgdorferi regardless of treatment. B. burgdorferi antigen was detected in the DRG and dorsal roots by immunofluorescence staining and confocal microscopy. Histopathology revealed leptomeningitis, vasculitis, and focal inflammation in the central nervous system; necrotizing focal myelitis in the cervical spinal cord; radiculitis; neuritis and demyelination in the spinal roots; and inflammation with neurodegeneration in the DRG that was concomitant with significant neuronal and satellite glial cell apoptosis. These changes were absent in the dexamethasone-treated animals. Electromyography revealed persistent abnormalities in F-wave chronodispersion in nerve roots of a few infected animals; which were absent in dexamethasone-treated animals. These results suggest that inflammation has a causal role in the pathogenesis of acute Lyme neuroborreliosis. PMID:25892509

Displacement of organelles in plant gravireceptor cells by vibrational forces and ultrasound.

NASA Astrophysics Data System (ADS)

Kuznetsov, O.; Nechitailo, G.; Kuznetsov, A.

Plant gravity perception can be studied by displacing statoliths inside receptor cells by forces other than gravity. Due to mechanical heterogeneity of statocytes various ponderomotive forces can be used for this purpose. In a plant subjected to non- symmetric vibrations statoliths experience inertial force proportional to the difference between their density and that of cytoplasm and to the instantaneous acceleration of the cell. This force causes cyclic motion of statoliths relative to cytoplasm and, depending on the profile of oscillations, can result in a net displacement of them (due to complex rheology of the cell interior), similar to sedimentation. This can be described as "vibrational" ponderomotive force acting on the statoliths. Vertically growing Arabidopsis seedlings, subjected to horizontal, sawtooth shaped oscillations (250 Hz, 1.5 mm amplitude), showed 17+/-2o root curvature toward and shoot curvature of 11+/-3o against the stronger acceleration. When the polarity of the oscillations was reversed, the direction of curvature of shoots and roots was also reversed. Control experiments with starchless mutants (TC7) produced no net curvature, which indicates that dense starch-filled amyloplasts are needed for the effect. These control experiments also eliminate touch-induced reactions or other side-effects as the cause of the curvature. Linum roots curved 25+/-7o . Ceratodon protonemata subjected to the same oscillations have shown displacement of plastids and curvature consistent with the pattern observed during graviresponse: positively gravitropic wwr mutant curved in the direction of the plastid displacement, WT curved in the opposite direction. Acoustic ponderomotive forces, originating from transfer of a sonic beam momentum to the medium due to sound scattering and attenuation in a mechanically heterogeneous system, also can displace statoliths. Vertical flax seedlings curved away from the ultrasonic source (800 kHz, 0.1 W/cm2 ) presumably as a reaction to amyloplasts displacement by acoustic forces. Besides investigating the graviperception mechanism, vibrational and acoustic forces can serve as tools for analyzing mechanical properties of cell interior. Practical applications of this technology could include providing directional stimuli for plants in microgravity by low doses of vibrations. Vibrations present on board of spacecraft may have vectorial effects on plants and other organisms, and their influence should be assessed.

Foot orgasm syndrome: a case report in a woman.

PubMed

Waldinger, Marcel D; de Lint, Govert J; van Gils, Ad P G; Masir, Farhad; Lakke, Egbert; van Coevorden, Ruben S; Schweitzer, Dave H

2013-08-01

Spontaneous orgasm triggered from inside the foot has so far not been reported in medical literature. The study aims to report orgasmic feelings in the left foot of a woman. A woman presented with complaints of undesired orgasmic sensations originating in her left foot. In-depth interview, physical examination, sensory testing, magnetic resonance imaging (MRI-scan), electromyography (EMG), transcutaneous electrical nerve stimulation (TENS), and blockade of the left S1 dorsal root ganglion were performed. The main outcomes are description of this clinical syndrome, results of TENS application, and S1 dorsal root ganglion blockade. Subtle attenuation of sensory amplitudes of the left suralis, and the left medial and lateral plantar nerve tracts was found at EMG. MRI-scan disclosed no foot abnormalities. TENS at the left metatarso-phalangeal joint-III of the left foot elicited an instant orgasmic sensation that radiated from plantar toward the vagina. TENS applied to the left side of the vagina elicited an orgasm that radiated to the left foot. Diagnostic blockade of the left S1 dorsal root ganglion with 0.8 mL bupivacaine 0.25 mg attenuated the frequency and intensity of orgasmic sensation in the left foot with 50% and 80%, respectively. Additional therapeutic blockade of the same ganglion with 0.8 mL bupivacaine 0.50 mg combined with pulsed radiofrequency treatment resulted in a complete disappearance of the foot-induced orgasmic sensations. Foot orgasm syndrome (FOS) is descibed in a woman. Blockade of the left S1 dorsal root ganglion alleviated FOS. It is hypothesized that FOS, occurring 1.5 years after an intensive care emergency, was caused by partial nerve regeneration (axonotmesis), after which afferent (C-fiber) information from a small reinnervated skin area of the left foot and afferent somatic and autonomous (visceral) information from the vagina on at least S1 spinal level is misinterpreted by the brain as being solely information originating from the vagina. © 2013 International Society for Sexual Medicine.

Comparison of the Lumbosacral Plexus Nerves Formation in Pampas Fox (Pseudalopex gymnocercus) and Crab-Eating Fox (Cerdocyon thous) in Relationship to Plexus Model in Dogs.

PubMed

Lorenzão, Caio José; Zimpel, Aline Veiga; Novakoski, Eduardo; da Silva, Aline Alves; Martinez-Pereira, Malcon Andrei

2016-03-01

In this study, the spinal nerves that constitute the lumbosacral plexus (LSP) were dissected in two species of South American wild canids (pampas fox-Pseudalopex gymnocercus, and crab-eating fox-Cerdocyon thous). The nerves origin and distribution in the pelvic limb were examined and compared with the LSP model of the dog described in the literature. The LSP was formed by whole ventral branches of L5 at L7 and S1, and a contribution of a one branch from S2, divided in three trunks. The trunk formed by union from L5-6 and S1 was divided into the cranial (cutaneus femoris lateralis nerve) medial (femoralis nerve) and lateral branches (obturatorius nerve). At the caudal part of the plexus, a thick branch, the ischiadicus plexus, was formed by contributions from L6-7 and S1-2. This root gives rise to the nerve branches which was disseminated to the pelvic limb (nerves gluteus cranial and gluteus caudal, cutaneus femoris caudalis and ischiadicus). The ischiadicus nerve was divided into fibularis communis and tibialis nerves. The tibialis nerve emits the cutaneus surae caudalis. The fibularis communis emits the cutaneus surae lateralis, fibularis superficialis and fibularis profundus. The pudendus nerve arises from S2 with contributions of one branch L7-S1 and one ramus of the cutaneus femoris lateralis. Still, one branch of S2 joins with S3 to form the rectales caudales nerve. These data provides an important anatomical knowledge of a two canid species of South American fauna, besides providing the effective surgical and clinical care of these animals. © 2016 Wiley Periodicals, Inc.

Acute repair of traumatic pan-brachial plexus injury: technical considerations and approaches.

PubMed

Abou-Al-Shaar, Hussam; Karsy, Michael; Ravindra, Vijay; Joyce, Evan; Mahan, Mark A

2018-01-01

Particularly challenging after complete brachial plexus avulsion is reestablishing effective hand function, due to limited neurological donors to reanimate the arm. Acute repair of avulsion injuries may enable reinnervation strategies for achieving hand function. This patient presented with pan-brachial plexus injury. Given its irreparable nature, the authors recommended multistage reconstruction, including contralateral C-7 transfer for hand function, multiple intercostal nerves for shoulder/triceps function, shoulder fusion, and spinal accessory nerve-to-musculocutaneous nerve transfer for elbow flexion. The video demonstrates distal contraction from electrical stimulation of the avulsed roots. Single neurorrhaphy of the contralateral C-7 transfer was performed along with a retrosternocleidomastoid approach. The video can be found here: https://youtu.be/GMPfno8sK0U .

Herpes zoster: A clinicocytopathological insight.

PubMed

Shah, Snehal; Singaraju, Sasidhar; Einstein, A; Sharma, Ashish

2016-01-01

Herpes zoster or shingles is reactivation of the varicella zoster virus that had entered the cutaneous nerve endings during an earlier episode of chicken pox traveled to the dorsal root ganglia and remained in a latent form. This condition is characterized by occurrence of multiple, painful, unilateral vesicles and ulceration which shows a typical single dermatome involvement. In this case report, we present a patient with herpes zoster involving the mandibular division of the trigeminal nerve, with unilateral vesicles over the right side of lower third of face along the trigeminal nerve tract, with intraoral involvement of buccal mucosa, labial mucosa and the tongue of the same side. Cytopathology revealed classic features of herpes infection including inclusion bodies, perinuclear halo and multinucleated cells.

Amyloplast Distribution Directs a Root Gravitropic Reaction

NASA Astrophysics Data System (ADS)

Kordyum, Elizabeth

Immobile higher plants are oriented in the gravitational field due to gravitropim that is a physiological growth reaction and consists of three phases: reception of a gravitational signal by statocytes, its transduction to the elongation zone, and finally the organ bending. As it is known, roots are characterized with positive gravitropism, i. e. they grow in the direction of a gravitational vector, stems - with negative gravitropism, i. e. they grow in the direction opposite to a gravitational vector. According to the Nemec’s and Haberlandt’s starch-statolith hypothesis, amyloplasts in diameter of 1.5 - 3 μ in average, which appear to act as gravity sensors and fulfill a statolythic function in the specialized graviperceptive cells - statocytes, sediment in the direction of a gravitational vector in the distal part of a cell, while a nucleus is in the proximal one. There are reasonable data that confirm the amyloplasts-statoliths participation in gravity perception: 1) correlation between the statoliths localization and the site of gravity sensing, 2) significant redistribution (sedimentation) of amyloplasts in statocytes under gravistimulation in comparison with other cell organelles, 3) root decreased ability to react on gravity under starch removal from amyloplasts, 4) starchless Arabidopsis thaliana mutants are agravitropic, 5) amyloplasts-statoliths do not sediment in the absence of the gravitational vector and are in different parts or more concentrated in the center of statocytes. Plant tropisms have been intensively studied for many decades and continue to be investigated. Nevertheless, the mechanisms by which plants do so is still not clearly explained and many questions on gravisensing and graviresponse remain unanswered. Even accepted hypotheses are now being questioned and recent data are critically evaluated. Although the available data show the Ca2+ and cytoskeleton participation in graviperception and signal transduction, the clear evidence with regard to the participation of calcium ions and cytoskeletal elements in these processes is therefore substantial but still circumstantial and requires new experimental data. Using a new model - weak combined magnetic fields (CMFs), which elicit a variety of responses in plants, growth rate and fresh weight, seed germination, Ca2+ concentration, membrane permeability, with a frequency resonance to cyclotron frequency of calcium ions, we firstly showed that a root positive gravitropic reaction changes on a negative one. In this case, the paradoxical displacement of amylopasts-statoliths to the upper longitudinal cell wall of statocytes occurred in the direction opposite to a gravitational vector. Displacement of amyloplasts, which contain the abundance of free Ca2+ in the stroma, was accompanied with Ca2+ redistribution in the same direction in the cytosol and increasing around amyloplasts in comparison with the state magnetic field. In the elongation zone, calcium ions accumulated in the upper site of a gravistimulated root unlike a positive gravitropic reaction, and a root is bending in the same direction in which amyloplasts are displacing. It seems that a root gravitropic reaction, if it began, occurs by an usual physiological way resulting in root bending with an opposite sign. It is of a special interest that a root is bending to the same direction with displacing of amyloplasts: in positive gravitropism - downwards, in negative gravitropism - upwards. Peculiarities of calcium ion redistribution in statocytes under gravistimulation in such combined magnetic field are a new additional evidence of a Ca2+ ion significant role in gravitropism. Thus, our data support the starch-statolith hypothesis but also pose the question as to which forces displace amyloplasts against the gravity vector? We hope that these data will stimulate new research to better understand the mechanisms of plant graviperception and graviresponse. Gravistimulation of a root in the CMF with the frequency resonance to the cyclotron frequency of Ca2+ ions is an effective model for future research of the mechanism of plant gravitropism, including a Ca2+ role in plant physiological growth reactions.

Functional outcomes of Gartland III supracondylar humerus fractures with early neurovascular complications in children: A retrospective observational study.

PubMed

Wang, Sung Il; Kwon, Tae Young; Hwang, Hong Pil; Kim, Jung Ryul

2017-06-01

This was a retrospective observational study. The aim of this study was to evaluate functional outcomes in children treated for Gartland III supracondylar humerus (SCH) fracture with neurovascular (NV) injuries using validated outcome measures. A secondary goal was to determine whether clinical parameters such as age at injury, sex, weight, fracture site, and/or direction of displacement could predict NV injury at the time of fracture or long-term functional outcomes in these patients.One hundred fifty-four patients of Gartland III SCH fractures between March 2004 and May 2013 were studied retrospectively. The patients were divided into 2 groups according to the presence of NV injury. Medical records and radiographs were reviewed to assess several parameters, including age, sex, weight, treatment intervention, the extremity involved, direction of fracture displacement, and NV injury. Functional outcome was assessed on final follow-up using the Pediatric Outcomes Data Collection Instrument (PODCI) and Quick Disabilities of the Arm, Shoulder, and Hand (Quick DASH) outcome measures. Statistical analysis was used to determine the relationship between NV injury and functional outcomes.There were 33 cases with Gartland III SCH fracture associated with NV injuries (10 cases of vascular compromise, 14 cases of neural injury, and 9 cases involving both vascular compromise and neural injury). There were significant differences between the 2 groups in age (P  =  .048), weight (P  =  .009), and direction of displacement (P  =  .004). Vascular compromise and median nerve injury were most common in fractures with posterolateral displacement, and radial nerve injuries were common in fractures with posteromedial displacement. The mean global function score in the PODCI was 91.4 points, and the mean Quick DASH score was 11.7 points, with excellent functional outcomes. No differences in outcomes were identified based upon age, fracture site, sex, weight, direction of displacement, or operative technique in NV injury patients (P > .05).The majority of patients with Gartland III SCH fractures associated with NV injuries returned to a high functioning level after treatment of their injuries. NV injury does not appear to influence functional outcomes. Good functional results can be expected regardless of age, fracture site, sex, weight, direction of displacement, and operative technique.

Hemilingual spasm: defining a new entity, its electrophysiological correlates and surgical treatment through microvascular decompression.

PubMed

Osburn, Leisha L; Møller, Aage R; Bhatt, Jay R; Cohen-Gadol, Aaron A

2010-07-01

We report on vascular compression syndrome of the 12th cranial nerve (hypoglossal), an occurrence not previously reported, and demonstrate, through corresponding objective electrophysiological evidence, that microvascular decompression of the hypoglossal nerve root can cure hemilingual spasm. A 52-year-old man had lower face muscle twitching and tongue spasms, which worsened with talking, chewing, or emotional stress. Carbamazepine offered only temporary relief, and relief from injections of botulinum toxin was insignificant. He was referred for surgical treatment. High-resolution magnetic resonance imaging of his posterior fossa contents revealed no obvious evidence of any compressive vessel along the facial nerve, but a compressive vessel along the hypoglossal nerve was apparent. The presence of preoperative tongue spasms encouraged interoperative monitoring of tongue motor responses. The facial nerve exit zone was explored, but microsurgical inspection of the seventh/eighth cranial nerve complex did not reveal any compressive vessel. However, at the anterolateral aspect of the medulla oblongata, the hypoglossal nerve was clearly compressed and distorted laterally by a large tortuous vertebral artery. When the artery was mobilized away from the nerve, the abnormal late electromyographic response to transcranial electrical stimulation disappeared; immediately after shredded Teflon was interpositioned between the artery and the nerve, the abnormal spontaneous tongue fasciculation also disappeared. The patient has remained spasm free 6 months after surgery. Hemilingual spasm may be caused by vascular contact/compression along cranial nerve XII at the lower brainstem and belong to the same family of cranial nerve hyperactivity disorders as hemifacial spasm.

Iatrogenic nerve injury in a national no-fault compensation scheme: an observational cohort study.

PubMed

Moore, A E; Zhang, J; Stringer, M D

2012-04-01

Iatrogenic nerve injury causes distress and disability, and often leads to litigation. The scale and profile of these injuries has only be estimated from published case reports/series and analyses of medicolegal claims.   To determine the current spectrum of iatrogenic nerve injury in New Zealand by analysing treatment injury claims accepted by a national no-fault compensation scheme. The Accident Compensation Corporation (ACC) provides national no-fault personal accident insurance cover, which extends to patients who have sustained a treatment injury from a registered healthcare professional. Nerve injury claims identified from 5227 treatment injury claims accepted by the ACC in 2009 were analysed. From 327 claims, 292 (89.3%) documenting 313 iatrogenic nerve injuries contained sufficient information for analysis. Of these, 211 (67.4%) occurred in 11 surgical specialties, particularly orthopaedics and general surgery; the remainder involved phlebotomy services, anaesthesia and various medical specialties. The commonest causes of injury were malpositioning (n = 40), venepuncture (n = 26), intravenous cannulation (n = 21) and hip arthroplasty (n = 21). Most commonly injured were the median nerve and nerve roots (n = 32 each), brachial plexus (n = 26), and the ulnar nerve (n = 25). At least 34 (11.6%) patients were referred for surgical management of their nerve injury. Iatrogenic nerve injuries are not rare and occur in almost all branches of medicine, with malpositioning under general anaesthesia and venepuncture as leading causes. Some of these injuries are probably unavoidable, but greater awareness of which nerves are at risk and in what context should facilitate the development and/or wider implementation of preventive strategies. © 2012 Blackwell Publishing Ltd.

Ascending aortic aneurysm causing hoarse voice: a variant of Ortner's syndrome

PubMed Central

Eccles, Sinan Robert; Banks, John; Kumar, Pankaj

2012-01-01

A 68-year-old man with a persistent hoarse voice was found to have a left vocal cord paralysis. Clinical examination revealed signs consistent with aortic regurgitation. Subsequent investigation revealed an ascending aortic aneurysm. He underwent aortic root and ascending aorta replacement and his hoarseness improved. Ortner's syndrome refers to hoarseness due to recurrent laryngeal nerve palsy secondary to a cardiovascular abnormality. Recurrent laryngeal nerve palsy due to aneurysmal dilation of the ascending aorta is extremely rare, with aneurysms of the aortic arch being a more common cause. PMID:23060380

Distribution of TRPV1- and TRPV2-immunoreactive afferent nerve endings in rat trachea.

PubMed

Yamamoto, Yoshio; Sato, Yoshikazu; Taniguchi, Kazuyuki

2007-12-01

Nociception in the trachea is important for respiratory modulation. We investigated the distribution, neurochemical characteristics, and origin of nerve endings with immunoreactivity for candidate sensor channels, TRPV1 and TRPV2, in rat trachea. In the epithelial layer, the intraepithelial nerve endings and dense subepithelial network of nerve fibers were immunoreactive for TRPV1. In contrast, TRPV2 immunoreactivity was observed mainly in nerve fibers of the tracheal submucosal layer and in several intrinsic ganglion cells in the peritracheal plexus. Double immunostaining revealed that some TRPV1-immunoreactive nerve fibers were also immunoreactive for substance P or calcitonin gene-related peptide, but neither neuropeptide colocalized with TRPV2. Injection of the retrograde tracer, fast blue, into the tracheal wall near the thoracic inlet demonstrated labeled neurons in the jugular, nodose, and dorsal root ganglia at segmental levels of C2-C8. In the jugular and nodose ganglia, 59.3% (70/118) and 10.7% (17/159), respectively, of fast blue-labeled neurons were immunoreactive for TRPV1, compared to 8.8% (8/91) and 2.6% (5/191) for TRPV2-immunoreactive. Our results indicate that TRPV1-immunoreactive nerve endings are important for tracheal nociception, and the different expression patterns of TRPV1 and TRPV2 with neuropeptides may reflect different subpopulations of sensory neurons.

Experimental observations of root growth in a controlled photoelastic granular material

NASA Astrophysics Data System (ADS)

Barés, Jonathan; Mora, Serge; Delenne, Jean-Yves; Fourcaud, Thierry

2017-06-01

We present a novel root observation apparatus capable of measuring the mechanical evolution of both the root network and the surrounding granular medium. The apparatus consists of 11 parallel growth frames, two of them being shearable, where the roots grow inside a photo-elastic or glass granular medium sandwiched between two pieces of glass. An automated system waters the plant and image each frame periodically in white light and between crossed polarisers. This makes it possible to follow (i) the root tips and (ii) the grain displacements as well as (iii) their inner pressure. We show how a root networks evolve in a granular medium and how it can mechanically stabilize it. This constitutes a model experiment to move forward in the understanding of the complex interaction between root growth and surrounding soil mechanical evolution.

Constriction of the buccal branch of the facial nerve produces unilateral craniofacial allodynia.

PubMed

Lewis, Susannah S; Grace, Peter M; Hutchinson, Mark R; Maier, Steven F; Watkins, Linda R

2017-08-01

Despite pain being a sensory experience, studies of spinal cord ventral root damage have demonstrated that motor neuron injury can induce neuropathic pain. Whether injury of cranial motor nerves can also produce nociceptive hypersensitivity has not been addressed. Herein, we demonstrate that chronic constriction injury (CCI) of the buccal branch of the facial nerve results in long-lasting, unilateral allodynia in the rat. An anterograde and retrograde tracer (3000MW tetramethylrhodamine-conjugated dextran) was not transported to the trigeminal ganglion when applied to the injury site, but was transported to the facial nucleus, indicating that this nerve branch is not composed of trigeminal sensory neurons. Finally, intracisterna magna injection of interleukin-1 (IL-1) receptor antagonist reversed allodynia, implicating the pro-inflammatory cytokine IL-1 in the maintenance of neuropathic pain induced by facial nerve CCI. These data extend the prior evidence that selective injury to motor axons can enhance pain to supraspinal circuits by demonstrating that injury of a facial nerve with predominantly motor axons is sufficient for neuropathic pain, and that the resultant pain has a neuroimmune component. Copyright © 2016 Elsevier Inc. All rights reserved.

Quadriplegic areflexic ICU illness: selective thick filament loss and normal nerve histology.

PubMed

Sander, Howard W; Golden, Marianna; Danon, Moris J

2002-10-01

Areflexic quadriplegia that occurs in the intensive care unit (ICU) is commonly ascribed to critical illness polyneuropathy based upon electrophysiology or muscle light microscopy. However, electron microscopy often documents a selective thick filament loss myopathy. Eight ICU patients who developed areflexic quadriplegia underwent biopsy. Seven patients had received steroids, and 2 had also received paralytic agents. Electrodiagnostic studies revealed absent or low-amplitude motor responses in 7. Sensory responses were normal in 5 of 6 and absent in 1. Initial electromyography revealed absent (n = 3), small (n = 3), or polyphasic (n = 1) motor unit potentials, and diffuse fibrillation potentials (n = 5). In all 8, light microscopy of muscle revealed numerous atrophic-angulated fibers and corelike lesions, and electron microscopy revealed extensive thick filament loss. Morphology of sural and intramuscular nerves, and, in one autopsied case, of the obturator nerve and multiple nerve roots, was normal. Although clinical, electrodiagnostic, and light microscopic features mimicked denervating disease, muscle electron microscopy revealed thick filament loss, and nerve histology was normal. This suggests that areflexic ICU quadriplegia is a primary myopathy and not an axonal polyneuropathy. Copyright 2002 Wiley Periodicals, Inc. Muscle Nerve 26: 499-505, 2002

Evaluation of a Computer-Assisted Dental Diagnostic System by Navy Hospital Corpsmen

DTIC Science & Technology

1989-06-23

hypersensitivity 1 Defective restoration Displace/mobility of tooth, favorable prognosis Displace/mobility of tooth, guarded prognosis 2 Endo / perio ... injury Osseous sequestrum 2 Occlusal trauma _1 Periodontal abscess 3 Periocoronitis/erupting tooth 2 Reversible pulpitis Root fracture Total...Trauma Related Injury 1 1 0 *Tooth, Specific 18 26 17 *Teeth, Generalized 1 1 0 *Gingiva, Specific Area 6 1 1 *Gingiva, Generalized Area 2 2 2 *Oral

[Relevance of nerve blocks in treating and diagnosing low back pain--is the quality decisive?].

PubMed

Hildebrandt, J

2001-12-01

Diagnostic nerve blocks: The popularity of neural blockade as a diagnostic tool in painful conditions, especially in the spine, is due to features like the unspecific character of spinal pain, the irrelevance of radiological findings and the purely subjective character of pain. It is said that apart from specific causes of pain and clear radicular involvement with obvious neurological deficits and corresponding findings of a prolapsed disc in MRI or CT pictures, a diagnosis of the anatomical cause of the pain can only be established if invasive tests are used [5]. These include zygapophyseal joint blocks, sacroiliacal joint blocks, disc stimulation and nerve root blocks. Under controlled conditions, it has been shown that among patients with chronic nonradicular low back pain, some 10-15% have zygapophyseal joint pain [58], some 15-20% have sacroiliacal joint pain [36, 59] and 40% have pain from internal disc disruption [60]. The diagnostic use of neural blockade rests on three premises. First, pathology causing pain is located in an exact peripheral location, and impulses from this site travel via a unique and consistent neural root. Second, injection of local aneasthetic totally abolishes sensory function of intended nerves and does not affect other nerves. Third, relief of pain after local anaesthetic block is attributable solely to block of the target afferent neural pathway. The validity of these assumptions is limited by complexities of anatomy, physiology, and psychology of pain perception and the effect of local anaesthetics on impulse conduction [28]. Facet joints: The prevalence of zygapophyseal joint pain among patients with low back pain seems to be between 15% and 40% [62], but apparently only 7% of patients have pure facet pain [8, 29]. Facet blockade is achieved either by injection of local anaesthetic into the joint space or around the medial branches of the posterior medial rami of the spinal nerves that innervate the joint. There are several problems with intraarticular facet injections, mainly failure to enter the joint capsule and rupture of the capsule during the injection [11]. There is no physiological means to test the adaequacy of medial nerve block, because the lower branches have no cutaneous innervation. Medial ramus blocks (for one joint two nerves have to be infiltrated) are as effective as intraarticular joint blocks [37]. Reproducibility of the test is not high, the specifity is only 65% [61]. For diagnosis of facet pain fluoroscopic control is always necessary as in the other diagnostic blocks. Sacroiliacal joint: Definitely the sacroiliacal joint can be the source of low back pain. Stimulation of the joint by injection in subjects without pain produces pain in the buttock, in the posterior thigh and the knee. There are many clinical tests which confirm the diagnosis, but the interrater reliability is moderate [53]. Intraarticular injection can be achieved in the lower part of the joint with fluoroscopic guidance only, but an accurate intraarticular injection, which is confirmed by contrast medium, even at this place is often difficult. It is not clear whether intraarticular spread is necessary to achieve efficacy. Discography: Two primary syndromes concerning the ventral compartment have been described: anular fissures of the disc and instability of the motion segment. In the syndrome of anular tear, leakage of nucleus pulposus material into the anulus fibrosus is considered to be the source of pain. The studies of Vaharanta [71] and Moneta [41] show a clear and significant correlation between disc pain and grade 3 fissures of the anulus fibrosus. intervertebral discs are difficult to anaesthetize. Intradiskal injections of local anaesthetics may succeed in relieving the patient's pain, but such injections are liable to yield false negative results if the injected agent fails to adequately infiltrate the nerve endings in the outer anulus fibrosus that mediate the patient's pain. In the majority of cases MRI provide adaequate information, but discography may be superior in early stages of anular tear and in clarifying the relation between imaging data and pain [71]. Selective spinal nerve injection: In patients with complicated radiculopathy, the contribution of root inflammation to pain may not be certain, or the level of pathology may be unclear. Diagnostic root blocks are indicated in the following situations: atypical topography of radicular pain, disc prolapses or central spinal stenosis at more than one level and monoradicular pain, lateral spinal stenosis, postnucleotomysyndrome. Injection of individual spinal nerves by paravertebral approach has to be used to elucidate the mechanism and source of pain in this unclear situations. The premise is that needle contact will identify the nerve that produces the patient's characteristic pain and that local anaesthetic delivered to the pathogenic nerve will be uniquely analgesic. Often, this method is used for surgical planning, such as determining the site of foraminotomy. All diagnostic nerve root blocks have to be done under fluoroscopic guidance. Pain relief with blockade of a spinal nerve cannot distinguish between pathology of the proximal nerve in the intervertebral foramen or pain transmitted from distal sites by that nerve. Besides, the tissue injury in the nerve's distribution and neuropathic pain (for instance as a result of root injury) likewise would be relieved by a proximal block of the nerve. Satisfactory needle placement could not be achieved in 10% of patient's at L4, 15% at L5 and 30% at S1 [28]. The positive predictive value of indicated radiculopathy confirmed by surgery ranged between 87-100% [14, 22]. The negative predictive value is poorly studied, because few patients in the negative test group had surgery. Negative predictive values were 27% and 38% of the small number of patients operated on despite a negative test. Only one prospective study was published, which showed a positive predictive value of 95% and an untested negative predictive value [66]. Some studies repeatedly demonstrated that pain relief by nerve root block does not predict success by neuroablative procedures, neither by dorsal rhyzotomy nor by dorsal gangliectomy [46]. Therapeutic nerve blocks - facet joints: Intraarticular injection of steroids offer no greater benefit than injections of normal saline [8, 15] and long lasting success is lacking. In this case, a denervation of the medial branches can be considered. To date three randomized controlled studies of radiofrequency facet denervation have been published. One study [20] reported only modest outcomes and its results remained inconclusive, another study [72] with a double blind controlled design showed some effects in a small selected group of patients (adjusted odds ratio 4.8) 3, 6 and 12 months after treatment, concerning not only reduction of pain but alleviating functional disability also. The third study (34a) showed no effect 3 months after treatment. Discogenic pain: Intradiscal radiofrequency lesions, intradiscal injections of steroids and phenol have been advocated, but there are no well controlled studies. Just recently, intradiscal lesion and denervation of the anulus has been described with promising results, but a randomized controlled study is lacking up to now [31, 55]. Epidural Steroids: Steroids relieve pain by reducing inflammation and by blocking transmission of nociceptive C-fiber input. Koes et al. [33] reviewed the randomized trials of epidural steroids: To date, 15 trials have been performed to evaluate the efficacy, 11 of which showed method scores of 50 points (from 100) ore more. The trials showed inconsistent results of epidural injections. Of the 15 trials, 8 reported positive results and 7 others reported negative results. Consequently the efficacy of epidural steroid injections has not yet been established. The benefits of epidural steroid injections seem to be of short duration only. Future efficacy studies, which are clearly needed, should take into account the apparent methological shortcomings. Furthermore, it is unclear which patients benefit from these injections. In our hands the injection technique can be much improved by fluoroscopic guidance of the needle, with a prone position of the patient, and lateral injection at the relevant level and with a small volume (1-2 ml) and low dose of corticosteroid (20 mg triamcinolone in the case of a monoradicular pain, for example). In the case of epidural adhesions in postoperative radicular pain [50], the study of Heafner showed that the additional effect of hyaloronidase and hypertonic saline to steroids was minimal. In our hands there was no effect in chronic radicular pain 3 months after the injection.

FGF and BMP derived from dorsal root ganglia regulate blastema induction in limb regeneration in Ambystoma mexicanum.

PubMed

Satoh, Akira; Makanae, Aki; Nishimoto, Yurie; Mitogawa, Kazumasa

2016-09-01

Urodele amphibians have a remarkable organ regeneration ability that is regulated by neural inputs. The identification of these neural inputs has been a challenge. Recently, Fibroblast growth factor (Fgf) and Bone morphogenic protein (Bmp) were shown to substitute for nerve functions in limb and tail regeneration in urodele amphibians. However, direct evidence of Fgf and Bmp being secreted from nerve endings and regulating regeneration has not yet been shown. Thus, it remained uncertain whether they were the nerve factors responsible for successful limb regeneration. To gather experimental evidence, the technical difficulties involved in the usage of axolotls had to be overcome. We achieved this by modifying the electroporation method. When Fgf8-AcGFP or Bmp7-AcGFP was electroporated into the axolotl dorsal root ganglia (DRG), GFP signals were detectable in the regenerating limb region. This suggested that Fgf8 and Bmp7 synthesized in neural cells in the DRG were delivered to the limbs through the long axons. Further knockdown experiments with double-stranded RNA interference resulted in impaired limb regeneration ability. These results strongly suggest that Fgf and Bmp are the major neural inputs that control the organ regeneration ability. Copyright © 2016 Elsevier Inc. All rights reserved.

Changes in VGLUT1 and VGLUT2 expression in rat dorsal root ganglia and spinal cord following spared nerve injury.

PubMed

Wang, Hong-Sheng; Yu, Gang; Wang, Zhi-Tong; Yi, Shou-Pu; Su, Rui-Bin; Gong, Ze-Hui

2016-10-01

Disturbance of glutamate homeostasis is a well-characterized mechanism of neuropathic pain. Vesicular glutamate transporters (VGLUTs) determine glutamate accumulation in synaptic vesicles and their roles in neuropathic pain have been suggested by gene-knockout studies. Here, we investigated the spatio-temporal changes in VGLUT expression during the development of neuropathic pain in wild-type rats. Spared nerve injury (SNI) induced mechanical allodynia from postoperative day 1 to at least day 14. Expression of VGLUT1 and VGLUT2 in dorsal root ganglia and spinal cord was examined by western blot analyses on different postoperative days. We observed that VGLUT2 were selectively upregulated in crude vesicle fractions from the ipsilateral lumbar enlargement on postoperative days 7 and 14, while VGLUT1 was transiently downregulated in ipsilateral DRG (day 4) and contralateral lumbar enlargement (day 1). Upregulation of VGLUT2 was not accompanied by alterations in vesicular expression of synaptotagmin or glyceraldehyde-3-phosphate dehydrogenase (GAPDH). Thus, VGLUTs expression, especially VGLUT2, is regulated following peripheral nerve injury. Temporal regulation of VGLUT2 expression in spinal cord may represent a novel presynaptic mechanism contributing to injury-induced glutamate imbalance and associated neuropathic pain. Copyright © 2016 Elsevier Ltd. All rights reserved.

Nerve growth factor released from a novel PLGA nerve conduit can improve axon growth

NASA Astrophysics Data System (ADS)

Lin, Keng-Min; Shea, Jill; Gale, Bruce K.; Sant, Himanshu; Larrabee, Patti; Agarwal, Jay

2016-04-01

Nerve injury can occur due to penetrating wounds, compression, traumatic stretch, and cold exposure. Despite prompt repair, outcomes are dismal. In an attempt to help resolve this challenge, in this work, a poly-lactic-co-glycolic acid (PLGA) nerve conduit with associated biodegradable drug reservoir was designed, fabricated, and tested. Unlike current nerve conduits, this device is capable of fitting various clinical scenarios by delivering different drugs without reengineering the whole system. To demonstrate the potential of this device for nerve repair, a series of experiments were performed using nerve growth factor (NGF). First, an NGF dosage curve was developed to determine the minimum NGF concentration for optimal axonal outgrowth on chick dorsal root ganglia (DRG) cells. Next, PLGA devices loaded with NGF were evaluated for sustained drug release and axon growth enhancement with the released drug. A 20 d in vitro release test was conducted and the nerve conduit showed the ability to meet and maintain the minimum NGF requirement determined previously. Bioactivity assays of the released NGF showed that drug released from the device between the 15th and 20th day could still promote axon growth (76.6-95.7 μm) in chick DRG cells, which is in the range of maximum growth. These novel drug delivery conduits show the ability to deliver NGF at a dosage that efficiently promotes ex vivo axon growth and have the potential for in vivo application to help bridge peripheral nerve gaps.

Root elongation against a constant force: experiment with a computerized feedback-controlled device

NASA Technical Reports Server (NTRS)

Kuzeja, P. S.; Lintilhac, P. M.; Wei, C.

2001-01-01

Axial force was applied to the root tip of corn (Zea mays L. cv. Merit) seedlings using a computerized, feedback-controlled mechanical device. The system's feedback capability allowed continuous control of a constant tip load, and the attached displacement transducer provided the time course of root elongation. Loads up to 7.5 g decreased the root elongation rate by 0.13 mm h-1 g-1, but loads 7.5 to 17.5 g decreased the growth rate by only 0.04 mm h-1 g-1. Loads higher than 18 g stopped root elongation completely. Measurement of the cross-sectional areas of the root tips indicated that the 18 g load had applied about 0.98 MPa of axial pressure to the root, thereby exceeding the root's ability to respond with increased turgor pressure. Recorded time-lapse images of loaded roots showed that radial thickening (swelling) occurred behind the root cap, whose cross-sectional area increased with tip load.

An analysis of reasons for failed back surgery syndrome and partial results after different types of surgical lumbar nerve root decompression.

PubMed

Bokov, Andrey; Isrelov, Alexey; Skorodumov, Alexander; Aleynik, Alexander; Simonov, Alexander; Mlyavykh, Sergey

2011-01-01

Despite the evident progress in treating vertebral column degenerative diseases, the rate of a so-called "failed back surgery syndrome" associated with pain and disability remains relatively high. However, this term has an imprecise definition and includes several different morbid conditions following spinal surgery, not all of which directly illustrate the efficacy of the applied technology; furthermore, some of them could even be irrelevant. To evaluate and systematize the reasons for persistent pain syndromes following surgical nerve root decompression. Prospective, nonrandomized, cohort study of 138 consecutive patients with radicular pain syndromes, associated with nerve root compression caused by lumbar disc herniation, and resistant to conservative therapy for at least one month. The minimal period of follow-up was 18 months. Hospital outpatient department, Russian Federation Pre-operatively, patients were examined clinically, applying the visual analog scale (VAS), Oswestry Disability Index (ODI), magnetic resonance imaging (MRI), discography and computed tomography (CT). According to the disc herniation morphology and applied type of surgery, all participants were divided into the following groups: for those with disc extrusion or sequester, microdiscectomy was applied (n = 65); for those with disc protrusion, nucleoplasty was applied (n = 46); for those with disc extrusion, nucleoplasty was applied (n = 27). After surgery, participants were examined clinically and the VAS and ODI were applied. All those with permanent or temporary pain syndromes were examined applying MRI imaging, functional roentgenograms, and, to validate the cause of pain syndromes, different types of blocks were applied (facet joint blocks, paravertebral muscular blocks, transforaminal and caudal epidural blocks). Group 1 showed a considerable rate of pain syndromes related to tissue damage during the intervention; the rates of radicular pain caused by epidural scar and myofascial pain were 12.3% and 26.1% respectively. Facet joint pain was found in 23.1% of the cases. Group 2 showed a significant rate of facet joint pain (16.9%) despite the minimally invasive intervention. The specificity of Group 3 was the very high rate of unresolved or recurred nerve root compression (63.0%); in other words, in the majority of cases, the aim of the intervention was not achieved. The results of the applied intervention were considered clinically significant if 50% pain relief on the VAS and a 40% decrease in the ODI were achieved. This study is limited because of the loss of participants to follow-up and because it is nonrandomized; also it could be criticized because the dynamics of numeric scores were not provided. The results of our study show that an analysis of the reasons for failures and partial effects of applied interventions for nerve root decompression may help to understand better the efficacy of the interventions and could be helpful in improving surgical strategies, otherwise the validity of the conclusion could be limited because not all sources of residual pain illustrate the applied technology efficacy. In the majority of cases, the cause of the residual or recurrent pain can be identified, and this may open new possibilities to improve the condition of patients presenting with failed back surgery syndrome.

Attenuation of TRPV1 by AMG-517 after nerve injury promotes peripheral axonal regeneration in rats.

PubMed

Bai, Juan; Liu, Fu; Wu, Li-Fei; Wang, Ya-Fang; Li, Xia-Qing

2018-01-01

Aims The main objective was to investigate the effects of the transient receptor potential cation channel subfamily V member 1 (TRPV1) on nerve regeneration following sciatic transection injury by functional blockage of TRPV1 using AMG-517, a specific blocker of TRPV1. Methods AMG-517 was injected into the area surrounding ipsilateral lumbar dorsal root ganglia 30 min after unilateral sciatic nerve transection. The number of sciatic axons and the expression of growth-associated protein-43 (GAP-43) and glial fibrillary acidic protein was examined using semithin sections, Western blot, and immunofluorescence analyses. Results Blockage of TRPV1 with AMG-517 markedly promoted axonal regeneration, especially at two weeks after sciatic injury; the number of axons was similar to the uninjured control group. After sciatic nerve transection, expression of glial fibrillary acidic protein was decreased and GAP-43 was increased at the proximal stump. However, the expression of both glial fibrillary acidic protein and GAP-43 increased significantly in AMG-517-treated groups. Conclusions TRPV1 may be an important therapeutic target to promote peripheral nerve regeneration after injury.

The course of the superficial peroneal nerve in relation to the ankle position: anatomical study with ankle arthroscopic implications

PubMed Central

Golanó, Pau; Sierevelt, Inger N.; van Dijk, C. Niek

2010-01-01

Despite the fact that the superficial peroneal nerve is the only nerve in the human body that can be made visible; iatrogenic damage to this nerve is the most frequently reported complication in anterior ankle arthroscopy. One of the methods to visualize the nerve is combined ankle plantar flexion and inversion. In the majority of cases, the superficial peroneal nerve can be made visible. The portals for anterior ankle arthroscopy are however created with the ankle in the neutral or slightly dorsiflexed position and not in combined plantar flexion and inversion. The purpose of this study was to undertake an anatomical study to the course of the superficial peroneal nerve in different positions of the foot and ankle. We hypothesize that the anatomical localization of the superficial peroneal nerve changes with different foot and ankle positions. In ten fresh frozen ankle specimens, a window, only affecting the skin, was made at the level of the anterolateral portal for anterior ankle arthroscopy in order to directly visualize the superficial peroneal nerve, or if divided, its terminal branches. Nerve movement was assessed from combined 10° plantar flexion and inversion to 5° dorsiflexion, standardized by the Telos stress device. Also for the 4th toe flexion, flexion of all the toes and for skin tensioning possible nerve movement was determined. The mean superficial peroneal nerve movement was 2.4 mm to the lateral side when the ankle was moved from 10° plantar flexion and inversion to the neutral ankle position and 3.6 mm to the lateral side from 10° plantar flexion and inversion to 5° dorsiflexion. Both displacements were significant (P < 0.01). The nerve consistently moves lateral when the ankle is manoeuvred from combined plantar flexion and inversion to the neutral or dorsiflexed position. If visible, it is therefore advised to create the anterolateral portal medial from the preoperative marking, in order to prevent iatrogenic damage to the superficial peroneal nerve. PMID:20224993

On a 3-D singularity element for computation of combined mode stress intensities

NASA Technical Reports Server (NTRS)

Atluri, S. N.; Kathiresan, K.

1976-01-01

A special three-dimensional singularity element is developed for the computation of combined modes 1, 2, and 3 stress intensity factors, which vary along an arbitrarily curved crack front in three dimensional linear elastic fracture problems. The finite element method is based on a displacement-hybrid finite element model, based on a modified variational principle of potential energy, with arbitrary element interior displacements, interelement boundary displacements, and element boundary tractions as variables. The special crack-front element used in this analysis contains the square root singularity in strains and stresses, where the stress-intensity factors K(1), K(2), and K(3) are quadratically variable along the crack front and are solved directly along with the unknown nodal displacements.

Peripheral Nerve Regeneration by Secretomes of Stem Cells from Human Exfoliated Deciduous Teeth.

PubMed

Sugimura-Wakayama, Yukiko; Katagiri, Wataru; Osugi, Masashi; Kawai, Takamasa; Ogata, Kenichi; Sakaguchi, Kohei; Hibi, Hideharu

2015-11-15

Peripheral nerve regeneration across nerve gaps is often suboptimal, with poor functional recovery. Stem cell transplantation-based regenerative therapy is a promising approach for axon regeneration and functional recovery of peripheral nerve injury; however, the mechanisms remain controversial and unclear. Recent studies suggest that transplanted stem cells promote tissue regeneration through a paracrine mechanism. We investigated the effects of conditioned media derived from stem cells from human exfoliated deciduous teeth (SHED-CM) on peripheral nerve regeneration. In vitro, SHED-CM-treated Schwann cells exhibited significantly increased proliferation, migration, and the expression of neuron-, extracellular matrix (ECM)-, and angiogenesis-related genes. SHED-CM stimulated neuritogenesis of dorsal root ganglia and increased cell viability. Similarly, SHED-CM enhanced tube formation in an angiogenesis assay. In vivo, a 10-mm rat sciatic nerve gap model was bridged by silicon conduits containing SHED-CM or serum-free Dulbecco's modified Eagle's medium. Light and electron microscopy confirmed that the number of myelinated axons and axon-to-fiber ratio (G-ratio) were significantly higher in the SHED-CM group at 12 weeks after nerve transection surgery. The sciatic functional index (SFI) and gastrocnemius (target muscle) wet weight ratio demonstrated functional recovery. Increased compound muscle action potentials and increased SFI in the SHED-CM group suggested sciatic nerve reinnervation of the target muscle and improved functional recovery. We also observed reduced muscle atrophy in the SHED-CM group. Thus, SHEDs may secrete various trophic factors that enhance peripheral nerve regeneration through multiple mechanisms. SHED-CM may therefore provide a novel therapy that creates a more desirable extracellular microenvironment for peripheral nerve regeneration.

Injury to the Lumbar Plexus and its Branches After Lateral Fusion Procedures: A Cadaver Study.

PubMed

Grunert, Peter; Drazin, Doniel; Iwanaga, Joe; Schmidt, Cameron; Alonso, Fernando; Moisi, Marc; Chapman, Jens R; Oskouian, Rod J; Tubbs, Richard Shane

2017-09-01

Neurologic deficits from lumbar plexus nerve injuries commonly occur in patients undergoing lateral approaches. However, it is not yet clear what types of injury occur, where anatomically they are located, or what mechanism causes them. We aimed to study 1) the topographic anatomy of lumbar plexus nerves and their injuries in human cadavers after lateral transpsoas approaches to the lumbar spine, 2) the structural morphology of those injuries, and 3) the topographic anatomy of the lumbar plexus throughout the mediolateral approach corridor. Fifteen adult fresh frozen cadaveric torsos (26 sides) underwent lateral approaches (L1-L5) by experienced lateral spine surgeons. The cadavers were subsequently opened and the entire plexus dissected and examined for nerve injuries. The topographic anatomy of the lumbar plexus and its branches, their injuries, and the morphology of these injuries were documented. Fifteen injuries were found with complete or partial nerve transections (Sunderland IV and V). Injuries were found throughout the mediolateral approach corridor. At L1/2, the iliohypogastric, ilioinguinal, and subcostal nerves were injured within the psoas major muscle, the retroperitoneal space, or the outer abdominal muscles and subcutaneous tissues. Genitofemoral nerve injuries were found in the retroperitoneal space. Nerve root injuries occurred within the retroperitoneal space and psoas muscle. Femoral nerve injuries were found only within the psoas major muscle. No obturator nerve injuries occurred. Lateral approaches can lead to structural nerve damage. Knowledge of the complex plexus anatomy, specifically its mediolateral course, is critical to avoid approach-related injuries. Copyright © 2017 Elsevier Inc. All rights reserved.

WenTong HuoXue Cream Can Inhibit the Reduction of the Pain-Related Molecule PLC-β3 in the Dorsal Root Ganglion of a Rat Model of Diabetic Peripheral Neuropathy

PubMed Central

Feng, Chengcheng; Xu, Lijuan; Guo, Shiyun; Chen, Qian; Shen, Yuguo; Zang, Deng

2018-01-01

WenTong HuoXue Cream (WTHX-Cream) has been shown to effectively alleviate clinical symptoms of diabetic peripheral neuropathy (DPN). This study investigated the gene and protein expression of the pain-related molecule PLC-β3 in the dorsal root ganglion (DRG) of DPN rats. 88 specific pathogen-free male Wistar rats were randomly divided into placebo (10 rats) and DPN model (78 rats) groups, and the 78 model rats were used to establish the DPN model by intraperitoneal injection of streptozotocin and were then fed a high-fat diet for 8 weeks. These rats were randomly divided into the model group, the high-, medium-, and low-dose WTHX-Cream + metformin groups, the metformin group, the capsaicin cream group, and the capsaicin cream + metformin group. After 4 weeks of continuous drug administration, the blood glucose, body weight, behavioral indexes, and sciatic nerve conduction velocity were measured. The pathological structure of the DRG and the sciatic nerve were observed. PLC-β3 mRNA and protein levels in the DRG of rats were measured. Compared with the model group, the high-dose WTHX-Cream group showed increased sciatic nerve conduction velocity, improved sciatic nerve morphological changes, and increased expression of PLC-β3 mRNA and protein in the DRG. This study showed that WTHX-Cream improves hyperalgesia symptoms of DPN by inhibiting the reduction of PLC-β3 mRNA and protein expression in the diabetic DRG of DPN rats. PMID:29599806

WenTong HuoXue Cream Can Inhibit the Reduction of the Pain-Related Molecule PLC-β3 in the Dorsal Root Ganglion of a Rat Model of Diabetic Peripheral Neuropathy.

PubMed

Feng, Chengcheng; Xu, Lijuan; Guo, Shiyun; Chen, Qian; Shen, Yuguo; Zang, Deng; Ma, Li

2018-01-01

WenTong HuoXue Cream (WTHX-Cream) has been shown to effectively alleviate clinical symptoms of diabetic peripheral neuropathy (DPN). This study investigated the gene and protein expression of the pain-related molecule PLC- β 3 in the dorsal root ganglion (DRG) of DPN rats. 88 specific pathogen-free male Wistar rats were randomly divided into placebo (10 rats) and DPN model (78 rats) groups, and the 78 model rats were used to establish the DPN model by intraperitoneal injection of streptozotocin and were then fed a high-fat diet for 8 weeks. These rats were randomly divided into the model group, the high-, medium-, and low-dose WTHX-Cream + metformin groups, the metformin group, the capsaicin cream group, and the capsaicin cream + metformin group. After 4 weeks of continuous drug administration, the blood glucose, body weight, behavioral indexes, and sciatic nerve conduction velocity were measured. The pathological structure of the DRG and the sciatic nerve were observed. PLC- β 3 mRNA and protein levels in the DRG of rats were measured. Compared with the model group, the high-dose WTHX-Cream group showed increased sciatic nerve conduction velocity, improved sciatic nerve morphological changes, and increased expression of PLC- β 3 mRNA and protein in the DRG. This study showed that WTHX-Cream improves hyperalgesia symptoms of DPN by inhibiting the reduction of PLC- β 3 mRNA and protein expression in the diabetic DRG of DPN rats.

Effectiveness of using low rate fluoroscopy to reduce an examiner's radiation dose during lumbar nerve root block.

PubMed

Yamane, Kentaro; Kai, Nobuo; Mazaki, Tetsuro; Miyamoto, Tadashi; Matsushita, Tomohiro

2018-06-13

Long-term exposure to radiation can lead to gene mutations and increase the risk of cancer. Low rate fluoroscopy has the potential to reduce the radiation exposure for both the examiner and the patient during various fluoroscopic procedures. The purpose of this study was to evaluate the impact of low rate fluoroscopy on reducing an examiner's radiation dose during nerve root block. A total of 101 lumbar nerve root block examinations were performed at our institute during a 6-month period. During the first 3 months, low rate fluoroscopy was performed at 7.5 frames/s (FPS) in 54 examinations, while 47 were performed at 15 FPS during the last 3 months. The examiner wore a torso protector, a neck protector, radiation protection gloves, and radiation protection glasses. Optically stimulated luminescence (OSL) dosimeter badges were placed on both the inside and the outside of each protector. The dosimeters were exchanged every month. Radiation doses (mSv) were measured as the integrated radiation quantity every month from the OSL dosimeters. The effective and equivalent doses for the hands, skin, and eyes were investigated. The mean monthly equivalent doses were significantly lower both inside and outside the hand protector for the 7.5 FPS versus 15 FPS (inside; P = 0.021, outside; P = 0.024). There were no significant differences between the two groups for the mean monthly calculated effective dose for each protector's condition. Radiation exposure was significantly reduced for the skin on the examiner's hand when using low rate fluoroscopy at 7.5 FPS, with no noticeable decrease in image quality or prolonged fluoroscopy time. Copyright © 2018. Published by Elsevier B.V.

Do L5 and s1 nerve root compressions produce radicular pain in a dermatomal pattern?

PubMed

Taylor, Christopher S; Coxon, Andrew J; Watson, Paul C; Greenough, Charles G

2013-05-20

Observational case series. To compare the pattern of distribution of radicular pain with published dermatome charts. Dermatomal charts vary and previous studies have demonstrated significant individual subject variation. Patients with radiologically and surgically proven nerve root compression (NRC) caused by prolapsed intervertebral disc completed computerized diagrams of the distribution of pain and pins and needles. Ninety-eight patients had L5 compressions and 83 had S1 compressions. The distribution of pain and pins and needles did not correspond well with dermatomal patterns. Of those patients with L5 NRC, only 22 (22.4%) recorded any hits on the L5 dermatome on the front, and only 60 (61.2%) on the back with only 13 (13.3%) on both. Only 1 (1.0%) patient placed more than 50% of their hits within the L5 dermatome. Of those patients with S1 NRC, only 3 (3.6%) recorded any hits on the S1 dermatome on the front, and only 64 (77.1%) on the back with only 15 (18.1%) on both. No patients placed more than 50% of their hits within the S1 dermatome. Regarding pins and needles, 27 (29.7%) patients with L5 NRC recorded hits on the front alone, 27 (29.7%) on the back alone, and 14 (15.4%) on both. Nineteen (20.9%) recorded more than 50% of hits within the L5 dermatome. Three (3.6%) patients with S1 NRC recorded hits on the front alone, 44 (53.0%) on the back alone, and 18 (21.7%) on both. Twelve (14.5%) recorded more than 50% of hits within the S1 dermatome. Patient report is an unreliable method of identifying the anatomical source of pain or paresthesia caused by nerve root compression. 4.

Irreversible Electroporation (IRE) in the Epidural Space of the Porcine Spine: Effects on Adjacent Structures

PubMed Central

Tam, Alda L.; Figueira, Tomas A.; Gagea, Mihai; Ensor, Joe E.; Dixon, Katherine; McWatters, Amanda; Gupta, Sanjay; Fuentes, David T.

2018-01-01

Purpose To determine the effects of irreversible electroporation (IRE) on the neural tissues following ablation in the epidural space of the porcine spine. Material and Methods The institutional animal care and use committee approved this study. With the IRE electrode positioned in the right lateral recess of the spinal epidural space, twenty CT-guided IRE ablations were performed using different applied voltages in four terminal animals. Histopathology of the neural tissues was assessed and used to select a voltage for a survival study. Sixteen CT-guided IRE ablations in the epidural space were performed using 667 V in four animals that were survived for 7-days. Clinical observation, magnetic resonance imaging (MRI) findings (obtained 6-hours post-IRE and pre-euthanasia),, histopathology, and simulated electric field strengths were assessed. A one-way analysis of variance (ANOVA) was used to compare the simulated electric field strength to histological findings. Results The mean distance between the IRE electrode and the spinal cord or nerve root was 1.71 ± 0.90 mm and 8.47 + 3.44 mm, respectively. There was no clinical evidence of paraplegia after IRE ablation. MRI and histopathology showed no neural-tissue lesions within the spinal cord; however, 31.2% (5/16) of nerve roots demonstrated moderate Wallerian degeneration in the survival group. Severity of histopathological injury in the survival group was not significantly related to either the simulated electric field strength or the distance between the IRE electrode and neural structure, (p >.05). Conclusions While the spinal cord appears resistant to the toxic effects of IRE, injury to the nerve roots may be a limiting factor for the use of IRE ablation in the epidural space. PMID:27266723

Three consecutive days of application of LED therapy is necessary to inhibit experimentally induced root resorption in rats: a microtomographic study.

PubMed

Higashi, Dayla Thyeme; Andrello, Avacir Casanova; Tondelli, Pedro Marcelo; de Oliveira Toginho Filho, Dari; de Paula Ramos, Solange

2017-01-01

Previous studies have suggested that phototherapy may modulate orthodontic tooth movement and the incidence of root resorption. We aimed to identify a minimal dose-response relationship to LED therapy with regard to orthodontic tooth movement (OTM) and root resorption in rats. Forty-eight male Wistar rats were divided into six groups with equal and random distribution: control (C) no intervention; three daily LED irradiation (CLED); submitted only to OTM (RR); OTM and LED irradiation on the first day (LED1); OTM and two LED irradiation on the first and second days (LED2); and OTM and three LED irradiation on the first, second, and third days (LED3). Orthodontic appliance was installed in groups RR, LED1, LED2, and LED3 to promote OTM. Animals from groups CLED, LED1, LED2, and LED3 received LED therapy (940 nm, 4 J, 4 J/cm2) according to each group of treatment. After 7 days, all the animals were sacrificed. The jaws were fixed and scanned with microtomography (micro-CT). The micro-CT images were reconstructed on 2D and 3D models. These models were used to identify and measure root resorption number and dimensions (diameter, depth, and volume). The distance between the first and second molars was used to verify tooth displacement. The results showed that LED3 group had significantly lower number of root resorption. The root resorption dimensions (diameter and depth) had no significant differences among the experimental groups. LED3 group had significant tooth displacement in relation to C and CLED groups. In conclusion, three daily LED therapy doses are required to inhibit root resorption after appliance of orthodontic forces.

Decreased glycolytic and tricarboxylic acid cycle intermediates coincide with peripheral nervous system oxidative stress in a murine model of type 2 diabetes.

PubMed

Hinder, Lucy M; Vivekanandan-Giri, Anuradha; McLean, Lisa L; Pennathur, Subramaniam; Feldman, Eva L

2013-01-01

Diabetic neuropathy (DN) is the most common complication of diabetes and is characterized by distal-to-proximal loss of peripheral nerve axons. The idea of tissue-specific pathological alterations in energy metabolism in diabetic complications-prone tissues is emerging. Altered nerve metabolism in type 1 diabetes models is observed; however, therapeutic strategies based on these models offer limited efficacy to type 2 diabetic patients with DN. Therefore, understanding how peripheral nerves metabolically adapt to the unique type 2 diabetic environment is critical to develop disease-modifying treatments. In the current study, we utilized targeted liquid chromatography-tandem mass spectrometry (LC/MS/MS) to characterize the glycolytic and tricarboxylic acid (TCA) cycle metabolomes in sural nerve, sciatic nerve, and dorsal root ganglia (DRG) from male type 2 diabetic mice (BKS.Cg-m+/+Lepr(db); db/db) and controls (db/+). We report depletion of glycolytic intermediates in diabetic sural nerve and sciatic nerve (glucose-6-phosphate, fructose-6-phosphate, fructose-1,6-bisphosphate (sural nerve only), 3-phosphoglycerate, 2-phosphoglycerate, phosphoenolpyruvate, and lactate), with no significant changes in DRG. Citrate and isocitrate TCA cycle intermediates were decreased in sural nerve, sciatic nerve, and DRG from diabetic mice. Utilizing LC/electrospray ionization/MS/MS and HPLC methods, we also observed increased protein and lipid oxidation (nitrotyrosine; hydroxyoctadecadienoic acids) in db/db tissue, with a proximal-to-distal increase in oxidative stress, with associated decreased aconitase enzyme activity. We propose a preliminary model, whereby the greater change in metabolomic profile, increase in oxidative stress, and decrease in TCA cycle enzyme activity may cause distal peripheral nerves to rely on truncated TCA cycle metabolism in the type 2 diabetes environment.

Assessment of nerve involvement in the lumbar spine: agreement between magnetic resonance imaging, physical examination and pain drawing findings

PubMed Central

2010-01-01

Background Detection of nerve involvement originating in the spine is a primary concern in the assessment of spine symptoms. Magnetic resonance imaging (MRI) has become the diagnostic method of choice for this detection. However, the agreement between MRI and other diagnostic methods for detecting nerve involvement has not been fully evaluated. The aim of this diagnostic study was to evaluate the agreement between nerve involvement visible in MRI and findings of nerve involvement detected in a structured physical examination and a simplified pain drawing. Methods Sixty-one consecutive patients referred for MRI of the lumbar spine were - without knowledge of MRI findings - assessed for nerve involvement with a simplified pain drawing and a structured physical examination. Agreement between findings was calculated as overall agreement, the p value for McNemar's exact test, specificity, sensitivity, and positive and negative predictive values. Results MRI-visible nerve involvement was significantly less common than, and showed weak agreement with, physical examination and pain drawing findings of nerve involvement in corresponding body segments. In spine segment L4-5, where most findings of nerve involvement were detected, the mean sensitivity of MRI-visible nerve involvement to a positive neurological test in the physical examination ranged from 16-37%. The mean specificity of MRI-visible nerve involvement in the same segment ranged from 61-77%. Positive and negative predictive values of MRI-visible nerve involvement in segment L4-5 ranged from 22-78% and 28-56% respectively. Conclusion In patients with long-standing nerve root symptoms referred for lumbar MRI, MRI-visible nerve involvement significantly underestimates the presence of nerve involvement detected by a physical examination and a pain drawing. A structured physical examination and a simplified pain drawing may reveal that many patients with "MRI-invisible" lumbar symptoms need treatment aimed at nerve involvement. Factors other than present MRI-visible nerve involvement may be responsible for findings of nerve involvement in the physical examination and the pain drawing. PMID:20831785

Sodium Channel Nav1.8 Underlies TTX-Resistant Axonal Action Potential Conduction in Somatosensory C-Fibers of Distal Cutaneous Nerves.

PubMed

Klein, Amanda H; Vyshnevska, Alina; Hartke, Timothy V; De Col, Roberto; Mankowski, Joseph L; Turnquist, Brian; Bosmans, Frank; Reeh, Peter W; Schmelz, Martin; Carr, Richard W; Ringkamp, Matthias

2017-05-17

Voltage-gated sodium (Na V ) channels are responsible for the initiation and conduction of action potentials within primary afferents. The nine Na V channel isoforms recognized in mammals are often functionally divided into tetrodotoxin (TTX)-sensitive (TTX-s) channels (Na V 1.1-Na V 1.4, Na V 1.6-Na V 1.7) that are blocked by nanomolar concentrations and TTX-resistant (TTX-r) channels (Na V 1.8 and Na V 1.9) inhibited by millimolar concentrations, with Na V 1.5 having an intermediate toxin sensitivity. For small-diameter primary afferent neurons, it is unclear to what extent different Na V channel isoforms are distributed along the peripheral and central branches of their bifurcated axons. To determine the relative contribution of TTX-s and TTX-r channels to action potential conduction in different axonal compartments, we investigated the effects of TTX on C-fiber-mediated compound action potentials (C-CAPs) of proximal and distal peripheral nerve segments and dorsal roots from mice and pigtail monkeys ( Macaca nemestrina ). In the dorsal roots and proximal peripheral nerves of mice and nonhuman primates, TTX reduced the C-CAP amplitude to 16% of the baseline. In contrast, >30% of the C-CAP was resistant to TTX in distal peripheral branches of monkeys and WT and Na V 1.9 -/- mice. In nerves from Na V 1.8 -/- mice, TTX-r C-CAPs could not be detected. These data indicate that Na V 1.8 is the primary isoform underlying TTX-r conduction in distal axons of somatosensory C-fibers. Furthermore, there is a differential spatial distribution of Na V 1.8 within C-fiber axons, being functionally more prominent in the most distal axons and terminal regions. The enrichment of Na V 1.8 in distal axons may provide a useful target in the treatment of pain of peripheral origin. SIGNIFICANCE STATEMENT It is unclear whether individual sodium channel isoforms exert differential roles in action potential conduction along the axonal membrane of nociceptive, unmyelinated peripheral nerve fibers, but clarifying the role of sodium channel subtypes in different axonal segments may be useful for the development of novel analgesic strategies. Here, we provide evidence from mice and nonhuman primates that a substantial portion of the C-fiber compound action potential in distal peripheral nerves, but not proximal nerves or dorsal roots, is resistant to tetrodotoxin and that, in mice, this effect is mediated solely by voltage-gated sodium channel 1.8 (Na V 1.8). The functional prominence of Na V 1.8 within the axonal compartment immediately proximal to its termination may affect strategies targeting pain of peripheral origin. Copyright © 2017 the authors 0270-6474/17/375205-11$15.00/0.

Drug Distribution into Peripheral Nerve.

PubMed

Liu, Houfu; Chen, Yan; Huang, Liang; Sun, Xueying; Fu, Tingting; Wu, Shengqian; Zhu, Xiaoyan; Zhen, Wei; Liu, Jihong; Lu, Gang; Cai, Wei; Yang, Ting; Zhang, Wandong; Yu, Xiaohong; Wan, Zehong; Wang, Jianfei; Summerfield, Scott G; Dong, Kelly; Terstappen, Georg C

2018-05-01

Little is known about the impact of the blood-nerve barrier (BNB) on drug distribution into peripheral nerves. In this study, we examined the peripheral nerve penetration in rats of 11 small-molecule drugs possessing diverse physicochemical and transport properties and ProTx-II, a tarantula venom peptide with molecular mass of 3826 Daltons. Each drug was administered as constant rate intravenous infusion for 6 hours (small molecules) or 24 hours (ProTx-II). Blood and tissues including brain, spinal cord, sciatic nerve, and dorsal root ganglion (DRG) were collected for drug concentration measurements. Unbound fractions of a set of compounds were determined by equilibrium dialysis method in rat blood, brains, spinal cords, sciatic nerves, and DRG. We also investigated the influence of N -[4-[2-(6,7-dimethoxy-3,4-dihydro-1 H -isoquinolin-2-yl)ethyl]phenyl]-5-methoxy-9-oxo-10 H -acridine-4-carboxamide (GF120918), a P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) inhibitor, on the peripheral nerve and central nervous system (CNS) tissue penetration of imatinib. We found that: 1) the unbound fraction in brain tissue homogenate highly correlates with that in the spinal cord, sciatic nerve, and DRG for a set of compounds and thus provides a good surrogate for spinal cord and peripheral nerve tissues, 2) small-molecule drugs investigated can penetrate the DRG and sciatic nerve, 3) P-gp and BCRP have a limited impact on the distribution of small-molecule drugs into peripheral nerves, and 4) DRG is permeable to ProTx-II, but its distribution into sciatic nerve and CNS tissues is restricted. These results demonstrate that small-molecule drugs investigated can penetrate peripheral nerve tissues, and P-gp/BCRP may not be a limiting factor at the BNB. Biologics as large as ProTx-II can access the DRG but not sciatic nerve and CNS tissues. Copyright © 2018 by The American Society for Pharmacology and Experimental Therapeutics.

Impaired micturition reflex caused by acute selective dorsal or ventral root(s) rhizotomy in anesthetized rats.

PubMed

Liao, Jiuan-Miaw; Cheng, Chen-Li; Lee, Shin-Da; Chen, Gin-Den; Chen, Kuo-Jung; Yang, Chao-Hsun; Pan, Shwu-Fen; Chen, Mei-Jung; Huang, Pei-Chen; Lin, Tzer-Bin

2006-01-01

To clarify the contributions of parasympathetic inputs and outputs to the micturition reflex. Intra-vesical pressure (IVP), external urethral sphincter electromyogram (EMG), pelvic afferent nerve activities (PANA), and pelvic efferent nerve activities (PENA) as well as the time-derived IVP (dIVP, an index of bladder contractility) were evaluated in intact and acute dorsal or ventral root(s) rhizotomized (DRX and VRX, respectively) rats. In DRX rats, when compared with that in intact stage, the voiding frequency was decreased (75 +/- 15% of intact, P < 0.05, n = 8), while the threshold pressure to trigger voiding contractions was significantly increased (187 +/- 75% of intact, P < 0.05, n = 8). In addition, several insufficient contractions (5.3 +/- 3.5 contractions/voiding, P < 0.05, n = 8) occurred in ahead of each voiding contraction. On the other hand, in VRX rats, the peak and rebound IVP were significantly decreased (90 +/- 3.5% and 75 +/- 11.3% of intact, P < 0.01, n = 8), while the threshold pressure was not affected (102 +/- 11% of intact, P = NS, n = 8). The time-derived parameters were significantly decreased in VRX (peak dIVP, 78 +/- 10.2%, rebound dIVP, 75 +/- 15.6%, minimal dIVP, 68 +/- 14% of intact, P < 0.01, n = 8) but only peak dIVP was decreased (85 +/- 11% of intact, P < 0.01, n = 8) in DRX rats. Acute selective DRX and VRX rat can be an animal model to investigate peripheral neural control in micturition functions.

Sacral root neuromodulation in idiopathic nonobstructive chronic urinary retention.

PubMed

Shaker, H S; Hassouna, M

1998-05-01

Sacral root neuromodulation is becoming a superior alternative to the standard treatment of idiopathic nonobstructive urinary retention. We report results in 20 successive patients who underwent sacral foramen implantation to restore bladder function. After an initial, thorough baseline assessment 20 patients 19.43 to 55.66 years old with idiopathic nonobstructive urinary retention underwent percutaneous nerve evaluation. Response was assessed by a detailed voiding diary. Responders underwent implantation with an S3 foramen implant, and were followed 1, 3 and 6 months postoperatively, and every 6 months thereafter. Sacral root neuromodulation restored voiding capability in these patients. Bladders were emptied with minimal post-void residual urine, which decreased from 78.3 to 5.5 to 10.2% of the total voided volume from baseline to postoperative followup. These results were reflected in uroflowmetry and pressure-flow studies, which were almost normal after implantation. Furthermore, the urinary tract infection rate decreased significantly and associated pelvic pain improved substantially. The Beck depression inventory and SF-36 quality of life questionnaire indicated some improvement but reached significance in only 1 item. In addition, cystometrography showed no significant difference after 6 months of implantation compared with baseline values. Complications were minimal and within expectations. Sacral root neuromodulation is an appealing, successful modality for nonobstructive urinary retention. Only patients who have a good response to percutaneous nerve evaluation are candidates for implantation. The high efficacy in patients who undergo implantation, relative simplicity of the procedure and low complication rate make this a treatment breakthrough in this difficult group.

Frontiers in Head and Neck Trauma: Clinical and Biomechanical.

DTIC Science & Technology

1998-06-19

Minerva fixation. As previously noted however, lateral mass plates have the risk for neurovascular injury (nerve root, vertebral artery), foraminal ...cord ischemia in CSM to include compromise of the anterior spinal veins, radicular arteries at the foraminal region, and vertebral artery narrowing as

[Combined surgical and physical treatment in traumatic painful syndromes of the cervical spine].

PubMed

Stachowski, B; Kaczmarek, J; Nosek, A; Kocur, L

1976-01-01

Clinical observations suggest the need for changing therapeutic management to a more active one in cases of cervical spine injury with damage to the spinal cord and nerve roots or brachial plexus. In 248 patients with these injuries treated initially conservatively the incidence of cervicobrachial pain was analysed. Neuralgic pains were present in 31.5% of cases, causalgic pains in 2.4% and sympathalgic pains in 2%. Conservative treatment conducted in these patients (89 cases) during many months after trauma had no effect on return of mobility. Long-term application of physioterapy prevented only temporarily the development of trophic changes and only partially relieved pains. Only surgical decompression of the spinal cord or spinal nerves with stabilization of damaged vertebrae caused disappearance of painful syndromes and improvement in the motor activity of the extremities. These observations show that early surgical intervention for decompression of the spinal cord, roots or brachial plexus should be advocated in these cases.

[Neck pain with and without affection of nerve roots].

PubMed

Nygaard, Øystein P; Rø, Magne; Andersen, Tor Inge; Zwart, John-Anker

2010-11-18

The prevalence of neck pain is 30-50 %, and those most affected are women and people in working age. Neck pain and other musculoskeletal complaints are among the most common causes for sick leave and disability pension in Norway, which emphasises the need for guidelines on diagnostic assessment and treatment of these patients. This paper is based on a review of "The Bone and Joint Decade 2000-2010 Task Force on Neck Pain and Its Associated Disorder", Cohrane overviews and some additional sources. A classification of neck pain into grades I-IV is recommended as a tool for daily clinical work. Unspecific neck pain (grades I and II) is still a challenge and the various underlying conditions are not well defined. Diagnostics and assessment of neck pain is mainly directed towards nerve root affection (grade III) or serious neck disease (grade IV). Treatment of neck pain is not sufficiently evidence-based, as there are few high-quality publications within this field. Research within the field is clearly needed and should be prioritized nationally.

Lumbar vertebral hemangioma mimicking lateral spinal canal stenosis: case report and review of literature.

PubMed

Syrimpeis, Vasileios; Vitsas, Vasileios; Korovessis, Panagiotis

2014-03-01

Context Hemangiomas are the commonest benign tumors of the spine. Most occur in the thoracolumbar spine and the majority are asymptomatic. Rarely, hemangiomas cause symptoms through epidural expansion of the involved vertebra, resulting in spinal canal stenosis, spontaneous epidural hemorrhage, and pathological burst fracture. Findings We report a rare case of a 73-year-old woman, who had been treated for two months for degenerative neurogenic claudication. On admission, magnetic resonance imaging and computed tomographic scans revealed a hemangioma of the third lumbar vertebra protruding to the epidural space producing lateral spinal stenosis and ipsilateral nerve root compression. The patient underwent successful right hemilaminectomy for decompression of the nerve root, balloon kyphoplasty with poly-methyl methacrylate (PMMA) and pedicle screw segmental stabilization. Postoperative course was uneventful. Conclusion In the elderly, this rare presentation of spinal stenosis due to hemangiomas may be encountered. Decompression and vertebral augmentation by means balloon kyphoplasty with PMMA plus segmental pedicle screw fixation is recommended.

Lumbar vertebral hemangioma mimicking lateral spinal canal stenosis: Case report and review of literature

PubMed Central

Syrimpeis, Vasileios; Vitsas, Vasileios; Korovessis, Panagiotis

2014-01-01

Context Hemangiomas are the commonest benign tumors of the spine. Most occur in the thoracolumbar spine and the majority are asymptomatic. Rarely, hemangiomas cause symptoms through epidural expansion of the involved vertebra, resulting in spinal canal stenosis, spontaneous epidural hemorrhage, and pathological burst fracture. Findings We report a rare case of a 73-year-old woman, who had been treated for two months for degenerative neurogenic claudication. On admission, magnetic resonance imaging and computed tomographic scans revealed a hemangioma of the third lumbar vertebra protruding to the epidural space producing lateral spinal stenosis and ipsilateral nerve root compression. The patient underwent successful right hemilaminectomy for decompression of the nerve root, balloon kyphoplasty with poly-methyl methacrylate (PMMA) and pedicle screw segmental stabilization. Postoperative course was uneventful. Conclusion In the elderly, this rare presentation of spinal stenosis due to hemangiomas may be encountered. Decompression and vertebral augmentation by means balloon kyphoplasty with PMMA plus segmental pedicle screw fixation is recommended. PMID:24090267

Spinal Nerve Root Haemangioblastoma Associated with Reactive Polycythemia

PubMed Central

Law, Eric K. C.; Lee, Ryan K. L.; Griffith, James F.; Siu, Deyond Y. W.; Ng, Ho Keung

2014-01-01

Haemangioblastomas are uncommon tumours that usually occur in the cerebellum and, less commonly, in the intramedullary spinal cord. The extramedullary spinal canal is an uncommon location for these tumours. Also haemangioblastoma at this site is not known to be associated with polycythemia. We present the clinical, imaging, and histological findings of an adult patient with extramedullary spinal haemangioblastoma and reactive polycythemia. Radiography and computed tomography (CT) revealed a medium-sized tumour that most likely arose from an extramedullary spinal nerve root. This tumour appeared to be slow growing as evidenced by the accompanying well-defined bony resorption with a sclerotic rim and mild neural foraminal widening. Magnetic resonance imaging revealed prominent flow voids consistent with tumoural hypervascularity. CT-guided biopsy was performed. Although preoperative angiographic embolisation was technically successful, excessive intraoperative tumour bleeding necessitated tumour debulking rather than complete tumour resection. Histology of the resected specimen revealed haemangioblastoma. Seven months postoperatively, the patients back pain and polycythemia have resolved. PMID:25431722

Lumbosacral Radiculoplexopathy as the Initial Presentation of Lymphoma: A Report of 4 Cases.

PubMed

Marquardt, Robert J; Li, Yuebing

2018-06-01

To evaluate the clinical, laboratory, and radiological features of 4 cases of biopsy-proven lymphomatous lumbosacral radiculoplexopathy. Retrospective chart review. All patients suffered from diffuse large B-cell lymphoma. A mean diagnostic delay of 10 months was encountered. Presenting symptoms in all 4 patients included back pain, radicular leg pain, and leg weakness, similar to spondylotic radiculopathy. Electrodiagnostic study showed axon loss radiculoplexopathy and magnetic resonance imaging of the lumbar spine or pelvis demonstrated nerve or nerve root enhancement. Increased uptake by lumbosacral roots/plexus on fluorodeoxyglucose-positron emission tomography aided diagnosis in 3 cases. Cytology was positive in 1 of 10 cerebrospinal fluid samples. Combined chemotherapy and radiation treatment led to clinicoradiological improvement, with residual neurological symptoms in all patients. Lymphomatous lumbosacral radiculoplexopathy should be considered in patients with progressive lumbosacral radicular symptoms. Magnetic resonance imaging and fluorodeoxyglucose-positron emission tomography, but not cerebrospinal fluid, are helpful in achieving early diagnosis. Treatment responses seem favorable.

Motion control of the rabbit ankle joint with a flat interface nerve electrode.

PubMed

Park, Hyun-Joo; Durand, Dominique M

2015-12-01

A flat interface nerve electrode (FINE) has been shown to improve fascicular and subfascicular selectivity. A recently developed novel control algorithm for FINE was applied to motion control of the rabbit ankle. A 14-contact FINE was placed on the rabbit sciatic nerve (n = 8), and ankle joint motion was controlled for sinusoidal trajectories and filtered random trajectories. To this end, a real-time controller was implemented with a multiple-channel current stimulus isolator. The performance test results showed good tracking performance of rabbit ankle joint motion for filtered random trajectories and sinusoidal trajectories (0.5 Hz and 1.0 Hz) with <10% average root-mean-square (RMS) tracking error, whereas the average range of ankle joint motion was between -20.0 ± 9.3° and 18.1 ± 8.8°. The proposed control algorithm enables the use of a multiple-contact nerve electrode for motion trajectory tracking control of musculoskeletal systems. © 2015 Wiley Periodicals, Inc.

Fuxianhuiid ventral nerve cord and early nervous system evolution in Panarthropoda

PubMed Central

Yang, Jie; Ortega-Hernández, Javier; Butterfield, Nicholas J.; Liu, Yu; Boyan, George S.; Hou, Jin-bo; Lan, Tian; Zhang, Xi-guang

2016-01-01

Panarthropods are typified by disparate grades of neurological organization reflecting a complex evolutionary history. The fossil record offers a unique opportunity to reconstruct early character evolution of the nervous system via exceptional preservation in extinct representatives. Here we describe the neurological architecture of the ventral nerve cord (VNC) in the upper-stem group euarthropod Chengjiangocaris kunmingensis from the early Cambrian Xiaoshiba Lagerstätte (South China). The VNC of C. kunmingensis comprises a homonymous series of condensed ganglia that extend throughout the body, each associated with a pair of biramous limbs. Submillimetric preservation reveals numerous segmental and intersegmental nerve roots emerging from both sides of the VNC, which correspond topologically to the peripheral nerves of extant Priapulida and Onychophora. The fuxianhuiid VNC indicates that ancestral neurological features of Ecdysozoa persisted into derived members of stem-group Euarthropoda but were later lost in crown-group representatives. These findings illuminate the VNC ground pattern in Panarthropoda and suggest the independent secondary loss of cycloneuralian-like neurological characters in Tardigrada and Euarthropoda. PMID:26933218

Fuxianhuiid ventral nerve cord and early nervous system evolution in Panarthropoda.

PubMed

Yang, Jie; Ortega-Hernández, Javier; Butterfield, Nicholas J; Liu, Yu; Boyan, George S; Hou, Jin-Bo; Lan, Tian; Zhang, Xi-Guang

2016-03-15

Panarthropods are typified by disparate grades of neurological organization reflecting a complex evolutionary history. The fossil record offers a unique opportunity to reconstruct early character evolution of the nervous system via exceptional preservation in extinct representatives. Here we describe the neurological architecture of the ventral nerve cord (VNC) in the upper-stem group euarthropod Chengjiangocaris kunmingensis from the early Cambrian Xiaoshiba Lagerstätte (South China). The VNC of C. kunmingensis comprises a homonymous series of condensed ganglia that extend throughout the body, each associated with a pair of biramous limbs. Submillimetric preservation reveals numerous segmental and intersegmental nerve roots emerging from both sides of the VNC, which correspond topologically to the peripheral nerves of extant Priapulida and Onychophora. The fuxianhuiid VNC indicates that ancestral neurological features of Ecdysozoa persisted into derived members of stem-group Euarthropoda but were later lost in crown-group representatives. These findings illuminate the VNC ground pattern in Panarthropoda and suggest the independent secondary loss of cycloneuralian-like neurological characters in Tardigrada and Euarthropoda.

The nerve supply of the lumbar intervertebral disc.

PubMed

Edgar, M A

2007-09-01

The anatomical studies, basic to our understanding of lumbar spine innervation through the sinu-vertebral nerves, are reviewed. Research in the 1980s suggested that pain sensation was conducted in part via the sympathetic system. These sensory pathways have now been clarified using sophisticated experimental and histochemical techniques confirming a dual pattern. One route enters the adjacent dorsal root segmentally, whereas the other supply is non-segmental ascending through the paravertebral sympathetic chain with re-entry through the thoracolumbar white rami communicantes. Sensory nerve endings in the degenerative lumbar disc penetrate deep into the disrupted nucleus pulposus, insensitive in the normal lumbar spine. Complex as well as free nerve endings would appear to contribute to pain transmission. The nature and mechanism of discogenic pain is still speculative but there is growing evidence to support a 'visceral pain' hypothesis, unique in the muscloskeletal system. This mechanism is open to 'peripheral sensitisation' and possibly 'central sensitisation' as a potential cause of chronic back pain.

Bladder volume-dependent excitatory and inhibitory influence of lumbosacral dorsal and ventral roots on bladder activity in rats

PubMed Central

Sugaya, Kimio; de Groat, William C.

2011-01-01

This study was undertaken to examine the role of the afferent and efferent pathways of the lumbosacral spinal nerve roots in the tonic control of bladder activity. Changes of isovolumetric bladder activity were recorded in 21 sympathectomized female rats under urethane anesthesia following transection of the dorsal (DRT) and ventral (VRT) lumbosacral spinal roots, and after intraperitoneal administration of hexamethonium. DRT altered the baseline intravesical pressure in a bladder volume-dependent manner in each animal. The percent change of baseline pressure after VRT following DRT was also dependent upon bladder volume. The percent change of baseline pressure after VRT alone was similarly dependent on bladder volume, but not after VRT followed by DRT. The percent change of baseline intravesical pressure (y)(−9 to +8 cm H2O, −56 to +46%) after DRT and VRT depended upon bladder volume (x)(y = 44.7 x −40.4) in all rats. Hexamethonium increased the amplitude of small myogenic bladder contractions after DRT and VRT. In conclusion, the bladder is tonically excited or inhibited by a local reflex pathway and by a parasympathetic reflex pathway that depends on connections with the lumbosacral spinal cord and the pelvic nerves. Both reflex mechanisms are influenced by bladder volume. PMID:17878597

[Orthodontic Management of the Impacted Mandibular Second Molar Tooth].

PubMed

Mah, Michael; Takada, Kenji

2016-09-01

When the mandibular permanent second molar becomes impacted, it is identified as a malocclusion that needs treatment as it often leads to unwanted complications such as caries and periodontitis of the adjacent permanent first molar. Other less common complications include root resorption of the adjacent first molar root or continued root development to be in close proximity to the inferior dental alveolar nerve. This paper seeks to differentiate various levels of severity of impaction and review treatment options that are considered clinically available for the proper management of the impacted mandibular permanent second molar. Treatment options that will be discussed in this article include timing of second molar removal for replacement by the third molar, relief of impaction via second premolar removal, surgical repositioning and the combination of third molar removal, surgical exposure and orthodontic uprighting of the impacted tooth. Depending on the severity of the impaction, most impactions can be easily and predictably corrected with nickel titanium archwires or auxillary open coil springs or uprighting springs. Uncommonly, the mandibular permanent second molar can become severely impacted and in close proximity to the inferior dentoalveolar nerve. In these instances, the use of temporary anchorage devices such as microimplants has shown to be successful in uprighting the severely impacted mandibular permanent second molars. © EDP Sciences, SFODF, 2016.

[Transcription of protein arginine N-methyltransferase genes in mouse dorsal root ganglia following peripheral nerve injury].

PubMed

Xu, Hua-Li; Xu, Shi-Yuan; Mo, Kai

2017-12-20

To investigate the changes in the transcription of protein arginine methylation enzyme family genes in the dorsal root ganglia (DRG) following peripheral nerve injury in mice. C57BL6 mouse models of neuropathic pain induced by peripheral nerve injury were established by bilateral L4 spinal nerve ligation (SNL). At 7 days after SNL or sham operation, the DRG tissue was collected for transcriptional analysis of 9 protein arginine methylation enzyme genes (Prmt1?3, Carm1, and Prmt5?9) using RNA?Seq to identify the differentially expressed genes in the injured DRGs. We also established mouse models of lateral L4 SNL and models of chronic constriction injury (CCI) of the sciatic nerve and tested the paw withdrawal frequency (PWF) in response to mechanical stimulation and paw withdrawal latency (PWL) in response to thermal stimulation on 0, 3, 7 and 14 days after SNL or CCI; the expressions of the differentially expressed genes in the injured DRGs were verified in the two models using RT?qPCR. Among the 9 protein arginine methylation enzyme family genes that were tissue?specifically expressed in the DRG, Prmt2 and Prmt3 showed the highest and Prmt6 showed the lowest basal expression. Compared with the sham?operated mice group, the mice receiving SNL exhibited upregulated Carm1 gene transcription (by 1.7 folds) but downregulated Prmt5, Prmt8 and Prmt9 transcription in the injured DRG (Prmt8 gene showed the most significant down?regulation by 16.3 folds). In mouse models of SNL and CCI, Carm1 gene expression increased progressively with time while Prmt8 transcription was obviously lowered on days 3, 7 and 14 after the injury; the transcription levels of Prmt1, Prmt5 and Prmt9 presented with no significant changes following the injuries. Both SNL and CCI induced mechanical allodynia and thermal hypersensitivities in the mice shown by increased PWF and decreased PWL on days 3, 7 and 14 after the injuries. Periphery nerve injury induces Carm1 upregulation and Prmt8 downregulation in the injured DRG in mice, which sheds light on new targets for treatment of neuropathic pain.

[Munchausen syndrome by proxy, an unusual presentation].

PubMed

Maida, A M; Molina, M E; Erazo, R

2001-08-01

We report a 12 year old girl that first consulted for fever with bilateral knee arthralgias. A neurological workout was started due to a progressive gait disturbance, but all results were incongruent with nerve or nerve root lesions, leading to the diagnosis of a functional paralysis. The patient worsened to the point of prostration. Due to the suspicion that the mother was inducing the symptoms, the patient was admitted to the hospital, where she improved notably. She was discharged walking. The improvement during hospital stay confirmed the diagnosis of a Münchausen by proxy syndrome, mimicking a disabling neurological condition.

[Pachymeningitis].

PubMed

Fain, O; Mekinian, A

2017-09-01

Pachymeningitis is a fibrosing and inflammatory process, which involves the dura mater. Some pachymeningitis are cranial and induce headaches and cranial nerve palsies. Others are spinal and responsible for nerve roots or spinal cord compression. MRI shows contrast enhancement thickening of the dura mater. Etiologies are infectious (syphilis, tuberculosis, etc.) or inflammatory (sarcoidosis, granulomatosis with polyangiitis, IgG4-related disease, idiopathic). Corticosteroids are the main treatment. The use of immunosuppressive drugs or rituximab is yet to be determined and probably adapted to each etiology. Copyright © 2017 Société Nationale Française de Médecine Interne (SNFMI). Published by Elsevier SAS. All rights reserved.

Retrograde tracing and toe spreading after experimental autologous nerve transplantation and crush injury of the sciatic nerve: a descriptive methodological study.

PubMed

van Neerven, Sabien Ga; Bozkurt, Ahmet; O'Dey, Dan Mon; Scheffel, Juliane; Boecker, Arne H; Stromps, Jan-Philipp; Dunda, Sebastian; Brook, Gary A; Pallua, Norbert

2012-04-30

Evaluation of functional and structural recovery after peripheral nerve injury is crucial to determine the therapeutic effect of a nerve repair strategy. In the present study, we examined the relationship between the structural evaluation of regeneration by means of retrograde tracing and the functional analysis of toe spreading. Two standardized rat sciatic nerve injury models were used to address this relationship. As such, animals received either a 2 cm sciatic nerve defect (neurotmesis) followed by autologous nerve transplantation (ANT animals) or a crush injury with spontaneous recovery (axonotmesis; CI animals). Functional recovery of toe spreading was observed over an observation period of 84 days. In contrast to CI animals, ANT animals did not reach pre-surgical levels of toe spreading. After the observation period, the lipophilic dye DiI was applied to label sensory and motor neurons in dorsal root ganglia (DRG; sensory neurons) and spinal cord (motor neurons), respectively. No statistical difference in motor or sensory neuron counts could be detected between ANT and CI animals.In the present study we could indicate that there was no direct relationship between functional recovery (toe spreading) measured by SSI and the number of labelled (motor and sensory) neurons evaluated by retrograde tracing. The present findings demonstrate that a multimodal approach with a variety of independent evaluation tools is essential to understand and estimate the therapeutic benefit of a nerve repair strategy.

Effect of cochlear nerve electrocautery on the adult cochlear nucleus.

PubMed

Iseli, Claire E; Merwin, William H; Klatt-Cromwell, Cristine; Hutson, Kendall A; Ewend, Matthew G; Adunka, Oliver F; Fitzpatrick, Douglas C; Buchman, Craig A

2015-04-01

Electrocauterization and subsequent transection of the cochlear nerve induce greater injury to the cochlear nucleus than sharp transection alone. Some studies show that neurofibromatosis Type 2 (NF2) patients fit with auditory brainstem implants (ABIs) fail to achieve speech perception abilities similar to ABI recipients without NF2. Reasons for these differences remain speculative. One hypothesis posits poorer performance to surgically induced trauma to the cochlear nucleus from electrocautery. Sustained electrosurgical depolarization of the cochlear nerve may cause excitotoxic-induced postsynaptic nuclear injury. Equally plausible is that cautery in the vicinity of the cochlear nucleus induces necrosis. The cochlear nerve was transected in anesthetized adult gerbils sharply with or without bipolar electrocautery at varying intensities. Gerbils were perfused at 1, 3, 5, and 7 days postoperatively; their brainstem and cochleas were embedded in paraffin and sectioned at 10 μm. Alternate sections were stained with flourescent markers for neuronal injury or Nissl substance. In additional experiments, anterograde tracers were applied directly to a sectioned eighth nerve to verify that fluorescent-labeled profiles seen were terminating auditory nerve fibers. Cochlear nerve injury was observed from 72 hours postoperatively and was identical across cases regardless of surgical technique. Postsynaptic cochlear nucleus injury was not seen after distal transection of the nerve. By contrast, proximal transection was associated with trauma to the cochlear nucleus. Distal application of bipolar electrocautery seems safe for the cochlear nucleus. Application near the root entry zone must be used cautiously because this may compromise nuclear viability needed to support ABI stimulation.

Progranulin overexpression in sensory neurons attenuates neuropathic pain in mice: Role of autophagy.

PubMed

Altmann, Christine; Hardt, Stefanie; Fischer, Caroline; Heidler, Juliana; Lim, Hee-Young; Häussler, Annett; Albuquerque, Boris; Zimmer, Béla; Möser, Christine; Behrends, Christian; Koentgen, Frank; Wittig, Ilka; Schmidt, Mirko H H; Clement, Albrecht M; Deller, Thomas; Tegeder, Irmgard

2016-12-01

Peripheral or central nerve injury is a frequent cause of chronic pain and the mechanisms are not fully understood. Using newly generated transgenic mice we show that progranulin overexpression in sensory neurons attenuates neuropathic pain after sciatic nerve injury and accelerates nerve healing. A yeast-2-hybrid screen revealed putative interactions of progranulin with autophagy-related proteins, ATG12 and ATG4b. This was supported by colocalization and proteomic studies showing regulations of ATG13 and ATG4b and other members of the autophagy network, lysosomal proteins and proteins involved in endocytosis. The association of progranulin with the autophagic pathway was functionally confirmed in primary sensory neurons. Autophagy and survival were impaired in progranulin-deficient neurons and improved in progranulin overexpressing neurons. Nerve injury in vivo caused an accumulation of LC3b-EGFP positive bodies in neurons of the dorsal root ganglia and nerves suggesting an impairment of autophagic flux. Overexpression of progranulin in these neurons was associated with a reduction of the stress marker ATF3, fewer protein aggregates in the injured nerve and enhanced stump healing. At the behavioral level, further inhibition of the autophagic flux by hydroxychloroquine intensified cold and heat nociception after sciatic nerve injury and offset the pain protection provided by progranulin. We infer that progranulin may assist in removal of protein waste and thereby helps to resolve neuropathic pain after nerve injury. Copyright © 2016 Elsevier Inc. All rights reserved.

Clinical findings and electrodiagnostic testing in 108 consecutive cases of lumbosacral radiculopathy due to herniated disc.

PubMed

Mondelli, M; Aretini, A; Arrigucci, U; Ginanneschi, F; Greco, G; Sicurelli, F

2013-10-01

This prospective study aim to examine whether clinical findings and electrodiagnostic testing (EDX) in patients with lumbosacral monoradiculopathy due to herniated disc (HD) differ as a function of root involvement level (L5 vs. S1) and HD zone (paramedian vs. intraforaminal). All patients with L4, L5 or S1 monoradiculopathy were prospectively enrolled at four electromyography (EMG) labs over a 2-year period. The diagnosis was based on a congruence between patient history and MRI evidence of HD. We compared the sensitivities of clinical findings and EDX with respect to both root involvement level and HD zone. Multivariate logistic regression was performed in order to verify the association between abnormal EMG, clinical, and neuroradiological findings. One hundred and eight patients (mean age 47.7 years, 55% men) were consecutively enrolled. Sensory loss in the painful dermatome was the most frequent finding at physical examination (56% of cases). EMG was abnormal in at least one muscle supplied by femoral and sciatic nerves in 45 cases (42%). Inclusion of paraspinal muscles increased sensitivity to only 49% and that of proximal muscles was useless. Motor and sensory neurography was seldom abnormal. The most frequent motor neurographic abnormalities were a delay of F-wave minimum latency and decrease in the compound muscle action potential amplitude from extensor digitorum brevis and abductor hallucis in L5 and S1 radiculopathies, respectively. Sensory neurography was usually normal, the amplitude of sensory nerve action potential was seldom reduced when HD injured dorsal root ganglion or postganglionic root fibres. Multivariate logistic regression analysis showed that EMG abnormalities could be predicted by myotomal muscular weakness, abnormal deep reflexes, and paraesthesiae. The only clinical and electrophysiological differences with respect to root involvement level concerned deep reflexes and motor neurography of deep peroneal and tibial nerves. Only some EDX parameters are helpful for the diagnosis of lumbosacral radiculopathy. EMG was abnormal in less than 50% of cases and its abnormalities could be predicted by some clinical findings. However, neurography is useful as a tool for differential diagnosis between radiculopathy and more diffuse disorders of the peripheral nervous system (polyneuropathy, plexopathy). Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Effect of beam channel plugging on the outcome of gamma knife radiosurgery for trigeminal neuralgia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Massager, Nicolas; Nissim, Ouzi; Murata, Noriko

2006-07-15

Purpose: We studied the influence of using plugs for brainstem protection during gamma knife radiosurgery (GKR) of trigeminal neuralgia (TN), with special emphasis on irradiation doses delivered to the trigeminal nerve, pain outcomes, and incidence of trigeminal dysfunction. Methods and Materials: A GKR procedure for TN using an anterior cisternal target and a maximum dose of 90 Gy was performed in 109 patients. For 49 patients, customized beam channel blocking (plugs) were used to reduce the dose delivered to the brainstem. We measured the mean and integrated radiation doses delivered to the trigeminal nerve and the clinical course of patientsmore » treated with and without plugs. Results: We found that blocking increases the length of trigeminal nerve exposed to high-dose radiation, resulting in a significantly higher mean dose to the trigeminal nerve. Significantly more of the patients with blocking achieved excellent pain outcomes (84% vs. 62%), but with higher incidences of moderate and bothersome trigeminal nerve dysfunction (37% mild/10% bothersome with plugs vs. 30% mild/2% bothersome without). Conclusions: The use of plugs to protect the brainstem during GKR treatment for TN increases the dose of irradiation delivered to the intracisternal trigeminal nerve root and is associated with an important increase in the incidence of trigeminal nerve dysfunction. Therefore, beam channel blocking should be avoided for 90 Gy-GKR of TN.« less

Arthroscopic treatment of femoral nerve paresthesia caused by an acetabular paralabral cyst.

PubMed

Kanauchi, Taira; Suganuma, Jun; Mochizuki, Ryuta; Uchikawa, Shinichi

2014-05-01

This report describes a rare case of femoral nerve paresthesia caused by an acetabular paralabral cyst of the hip joint. A 68-year-old woman presented with a 6-month history of right hip pain and paresthesia along the anterior thigh and radiating down to the anterior aspect of the knee. Radiography showed osteoarthritis with a narrowed joint space in the right hip joint. Magnetic resonance imaging showed a cyst with low T1- and high T2-weighted signal intensity arising from a labral tear at the anterior aspect of the acetabulum. The cyst was connected to the joint space and displaced the femoral nerve to the anteromedial side. The lesion was diagnosed as an acetabular paralabral cyst causing femoral neuropathy. Because the main symptom was femoral nerve paresthesia and the patient desired a less invasive procedure, arthroscopic labral repair was performed to stop synovial fluid flow to the paralabral cyst that was causing the femoral nerve paresthesia. After surgery, the cyst and femoral nerve paresthesia disappeared. At the 18-month follow-up, the patient had no recurrence. There have been several reports of neurovascular compression caused by the cyst around the hip joint. To the authors' knowledge, only 3 cases of acetabular paralabral cysts causing sciatica have been reported. The current patient appears to represent a rare case of an acetabular paralabral cyst causing femoral nerve paresthesia. The authors suggest that arthroscopic labral repair for an acetabular paralabral cyst causing neuropathy can be an option for patients who desire a less invasive procedure. Copyright 2014, SLACK Incorporated.

Neuronal expression of the ubiquitin ligase Nedd4-2 in rat dorsal root ganglia: modulation in the spared nerve injury model of neuropathic pain.

PubMed

Cachemaille, M; Laedermann, C J; Pertin, M; Abriel, H; Gosselin, R-D; Decosterd, I

2012-12-27

Neuronal hyperexcitability following peripheral nerve lesions may stem from altered activity of voltage-gated sodium channels (VGSCs), which gives rise to allodynia or hyperalgesia. In vitro, the ubiquitin ligase Nedd4-2 is a negative regulator of VGSC α-subunits (Na(v)), in particular Na(v)1.7, a key actor in nociceptor excitability. We therefore studied Nedd4-2 in rat nociceptors, its co-expression with Na(v)1.7 and Na(v)1.8, and its regulation in pathology. Adult rats were submitted to the spared nerve injury (SNI) model of neuropathic pain or injected with complete Freund's adjuvant (CFA), a model of inflammatory pain. L4 dorsal root ganglia (DRG) were analyzed in sham-operated animals, seven days after SNI and 48 h after CFA with immunofluorescence and Western blot. We observed Nedd4-2 expression in almost 50% of DRG neurons, mostly small and medium-sized. A preponderant localization is found in the non-peptidergic sub-population. Additionally, 55.7 ± 2.7% and 55.0 ± 3.6% of Nedd4-2-positive cells are co-labeled with Na(v)1.7 and Na(v)1.8 respectively. SNI significantly decreases the proportion of Nedd4-2-positive neurons from 45.9 ± 1.9% to 33.5 ± 0.7% (p<0.01) and the total Nedd4-2 protein to 44% ± 0.13% of its basal level (p<0.01, n=4 animals in each group, mean ± SEM). In contrast, no change in Nedd4-2 was found after peripheral inflammation induced by CFA. These results indicate that Nedd4-2 is present in nociceptive neurons, is downregulated after peripheral nerve injury, and might therefore contribute to the dysregulation of Na(v)s involved in the hyperexcitability associated with peripheral nerve injuries. Copyright © 2012 IBRO. Published by Elsevier Ltd. All rights reserved.

TNF-α contributes to up-regulation of Nav1.3 and Nav1.8 in DRG neurons following motor fiber injury.

PubMed

He, Xin-Hua; Zang, Ying; Chen, Xi; Pang, Rui-Ping; Xu, Ji-Tian; Zhou, Xiang; Wei, Xu-Hong; Li, Yong-Yong; Xin, Wen-Jun; Qin, Zhi-Hai; Liu, Xian-Guo

2010-11-01

A large body of evidence has demonstrated that the ectopic discharges of action potentials in primary afferents, resulted from the abnormal expression of voltage gated sodium channels (VGSCs) in dorsal root ganglion (DRG) neurons following peripheral nerve injury are important for the development of neuropathic pain. However, how nerve injury affects the expression of VGSCs is largely unknown. Here, we reported that selective injury of motor fibers by L5 ventral root transection (L5-VRT) up-regulated Nav1.3 and Nav1.8 at both mRNA and protein level and increased current densities of TTX-S and TTX-R channels in DRG neurons, suggesting that nerve injury may up-regulate functional VGSCs in sensory neurons indirectly. As the up-regulated Nav1.3 and Nav1.8 were highly co-localized with TNF-α, we tested the hypothesis that the increased TNF-α may lead to over-expression of the sodium channels. Indeed, we found that peri-sciatic administration of recombinant rat TNF-α (rrTNF) without any nerve injury, which produced lasting mechanical allodynia, also up-regulated Nav1.3 and Nav1.8 in DRG neurons in vivo and that rrTNF enhanced the expression of Nav1.3 and Nav1.8 in cultured adult rat DRG neurons in a dose-dependent manner. Furthermore, inhibition of TNF-α synthesis, which prevented neuropathic pain, strongly inhibited the up-regulation of Nav1.3 and Nav1.8. The up-regulation of the both channels following L5-VRT was significantly lower in TNF receptor 1 knockout mice than that in wild type mice. These data suggest that increased TNF-α may be responsible for up-regulation of Nav1.3 and Nav1.8 in uninjured DRG neurons following nerve injury. Copyright © 2010 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

Axotomy of tributaries of the pelvic and pudendal nerves induces changes in the neurochemistry of mouse dorsal root ganglion neurons and the spinal cord.

PubMed

McCarthy, Carly J; Tomasella, Eugenia; Malet, Mariana; Seroogy, Kim B; Hökfelt, Tomas; Villar, Marcelo J; Gebhart, G F; Brumovsky, Pablo R

2016-05-01

Using immunohistochemical techniques, we characterized changes in the expression of several neurochemical markers in lumbar 4-sacral 2 (L4-S2) dorsal root ganglion (DRG) neuron profiles (NPs) and the spinal cord of BALB/c mice after axotomy of the L6 and S1 spinal nerves, major tributaries of the pelvic (targeting pelvic visceral organs) and pudendal (targeting perineum and genitalia) nerves. Sham animals were included. Expression of cyclic AMP-dependent transcription factor 3 (ATF3), calcitonin gene-related peptide (CGRP), transient receptor potential cation channel subfamily V, member 1 (TRPV1), tyrosine hydroxylase (TH) and vesicular glutamate transporters (VGLUT) types 1 and -2 was analysed seven days after injury. L6-S1 axotomy induced dramatic de novo expression of ATF3 in many L6-S1 DRG NPs, and parallel significant downregulations in the percentage of CGRP-, TRPV1-, TH- and VGLUT2-immunoreactive (IR) DRG NPs, as compared to their expression in uninjured DRGs (contralateral L6-S1-AXO; sham mice); VGLUT1 expression remained unaltered. Sham L6-S1 DRGs only showed a small ipsilateral increase in ATF3-IR NPs (other markers were unchanged). L6-S1-AXO induced de novo expression of ATF3 in several lumbosacral spinal cord motoneurons and parasympathetic preganglionic neurons; in sham mice the effect was limited to a few motoneurons. Finally, a moderate decrease in CGRP- and TRPV1-like-immunoreactivities was observed in the ipsilateral superficial dorsal horn neuropil. In conclusion, injury of a mixed visceral/non-visceral nerve leads to considerable neurochemical alterations in DRGs matched, to some extent, in the spinal cord. Changes in these and potentially other nociception-related molecules could contribute to pain due to injury of nerves in the abdominopelvic cavity.

Sciatic Nerve Intrafascicular Lidocaine Injection-induced Peripheral Neuropathic Pain: Alleviation by Systemic Minocycline Administration.

PubMed

Cheng, Kuang-I; Wang, Hung-Chen; Wu, Yi-Chia; Tseng, Kuang-Yi; Chuang, Yi-Ta; Chou, Chao-Wen; Chen, Ping-Luen; Chang, Lin-Li; Lai, Chung-Sheng

2016-06-01

Peripheral nerve block guidance with a nerve stimulator or echo may not prevent intrafascicular injury. This study investigated whether intrafascicular lidocaine induces peripheral neuropathic pain and whether this pain can be alleviated by minocycline administration. A total of 168 male Sprague-Dawley rats were included. In experiment 1, 2% lidocaine (0.1 mL) was injected into the left sciatic nerve. Hindpaw responses to thermal and mechanical stimuli, and sodium channel and activating transcription factor (ATF-3) expression in dorsal root ganglion (DRG) and glial cells in the spinal dorsal horn (SDH), were measured on days 4, 7, 14, 21, and 28. On the basis of the results in experiment 1, rats in experiment 2 were divided into sham, extraneural, intrafascicular, peri-injury minocycline, and postinjury minocycline groups. Behavioral responses, macrophage recruitment, expression changes of myelin basic protein and Schwann cells in the sciatic nerve, dysregulated expression of ATF-3 in the DRG, and activated glial cells in L5 SDH were assessed on days 7 and 14. Intrafascicular lidocaine induced mechanical allodynia, downregulated Nav1.8, increased ATF-3 expression in the DRG, and activated glial cells in the SDH. Increased expression of macrophages, Schwann cells, and myelin basic protein was found in the sciatic nerve. Minocycline attenuated intrafascicular lidocaine-induced neuropathic pain and nerve damage significantly. Peri-injury minocycline was better than postinjury minocycline administration in alleviating mechanical behaviors, mitigating macrophage recruitment into the sciatic nerve, and suppressing activated microglial cells in the spinal cord. Systemic minocycline administration alleviates intrafascicular lidocaine injection-induced peripheral nerve damage.

Mirror-image pain after nerve reconstruction in rats is related to enhanced density of epidermal peptidergic nerve fibers.

PubMed

Kambiz, S; Brakkee, E M; Duraku, L S; Hovius, S E R; Ruigrok, T J H; Walbeehm, E T

2015-05-01

Mirror-image pain is a phenomenon in which unprovoked pain is detected on the uninjured contralateral side after unilateral nerve injury. Although it has been implicated that enhanced production of nerve growth factor (NGF) in the contralateral dorsal root ganglion is important in the development of mirror-image pain, it is not known if this is related to enhanced expression of nociceptive fibers in the contralateral skin. Mechanical and thermal sensitivity in the contralateral hind paw was measured at four different time points (5, 10, 20 and 30weeks) after transection and immediate end-to-end reconstruction of the sciatic nerve in rats. These findings were compared to the density of epidermal (peptidergic and non-peptidergic) nerve fibers on the contralateral hind paw. Mechanical hypersensitivity of the contralateral hind paw was observed at 10weeks PO, a time point in which both subgroups of epidermal nerve fibers reached control values. Thermal hypersensitivity was observed with simultaneous increase in the density of epidermal peptidergic nerve fibers of the contralateral hind paw at 20weeks PO. Both thermal sensitivity and the density of epidermal nerve fibers returned to control values 30weeks PO. We conclude that changes in skin innervation and sensitivity are present on the uninjured corresponding side in a transient pain model. Therefore, the contralateral side cannot serve as control. Moreover, the current study confirms the involvement of the peripheral nervous system in the development of mirror-image pain. Copyright © 2015 Elsevier Inc. All rights reserved.

In vitro evaluation of gel-encapsulated adipose derived stem cells: Biochemical cues for in vivo peripheral nerve repair.

PubMed

de Luca, A C; Fonta, C M; Raffoul, W; di Summa, P G; Lacour, S P

2018-03-01

Adipose-derived stem cells (ASC) are becoming one of the most exploited cells in peripheral nerve repair. They are fast-growing and able to protect neurons from apoptosis; they can reduce post-injury latency and the risk of muscle atrophy. This study evaluates laminin-loaded fibrin gel as an ASC-carrying scaffold for nerve repair. In vitro, ASC retained their proliferative activity but showed significant increase in proliferation rate when encapsulated in gels with low laminin concentrations (i.e., 1 μg/mL). We observed a linear decrease of ASC proliferation rate with increasing laminin concentration from 1 to 100 μg/mL. We next examined the effect of the ASC-carrying fibrin gels on in vitro dorsal root ganglia (DRG) neurite extension, then in vivo sciatic nerve regeneration in adult rats. The ASC-carrying gel was embedded in 15-mm-long, 1.5-mm-diameter polydimethylsiloxane regenerative conduits for in vivo evaluation. At 8-week post implantation, robust regeneration was observed across the long gap. Taken together, these results suggest ASC-carrying gels are a potential path to improve the efficacy of nerve regeneration through artificial guidance conduits and electrode nerve interfaces. Copyright © 2017 John Wiley & Sons, Ltd.

A Physicochemically Optimized and Neuroconductive Biphasic Nerve Guidance Conduit for Peripheral Nerve Repair.

PubMed

Ryan, Alan J; Lackington, William A; Hibbitts, Alan J; Matheson, Austyn; Alekseeva, Tijna; Stejskalova, Anna; Roche, Phoebe; O'Brien, Fergal J

2017-12-01

Clinically available hollow nerve guidance conduits (NGCs) have had limited success in treating large peripheral nerve injuries. This study aims to develop a biphasic NGC combining a physicochemically optimized collagen outer conduit to bridge the transected nerve, and a neuroconductive hyaluronic acid-based luminal filler to support regeneration. The outer conduit is mechanically optimized by manipulating crosslinking and collagen density, allowing the engineering of a high wall permeability to mitigate the risk of neuroma formation, while also maintaining physiologically relevant stiffness and enzymatic degradation tuned to coincide with regeneration rates. Freeze-drying is used to seamlessly integrate the luminal filler into the conduit, creating a longitudinally aligned pore microarchitecture. The luminal stiffness is modulated to support Schwann cells, with laminin incorporation further enhancing bioactivity by improving cell attachment and metabolic activity. Additionally, this biphasic NGC is shown to support neurogenesis and gliogenesis of neural progenitor cells and axonal outgrowth from dorsal root ganglia. These findings highlight the paradigm that a successful NGC requires the concerted optimization of both a mechanical support phase capable of bridging a nerve defect and a neuroconductive phase with an architecture capable of supporting both Schwann cells and neurons in order to achieve functional regenerative outcome. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Peripheral nerve pathology, including aberrant Schwann cell differentiation, is ameliorated by doxycycline in a laminin-α2-deficient mouse model of congenital muscular dystrophy

PubMed Central

Homma, Sachiko; Beermann, Mary Lou; Miller, Jeffrey Boone

2011-01-01

The most common form of childhood congenital muscular dystrophy, Type 1A (MDC1A), is caused by mutations in the human LAMA2 gene that encodes the laminin-α2 subunit. In addition to skeletal muscle deficits, MDC1A patients typically show a loss of peripheral nerve function. To identify the mechanisms underlying this loss of nerve function, we have examined pathology and cell differentiation in sciatic nerves and ventral roots of the laminin-α2-deficient (Lama2−/−) mice, which are models for MDC1A. We found that, compared with wild-type, sciatic nerves of Lama2−/− mice had a significant increase in both proliferating (Ki67+) cells and premyelinating (Oct6+) Schwann cells, but also had a significant decrease in both immature/non-myelinating [glial fibrillary acidic protein (GFAP)+] and myelinating (Krox20+) Schwann cells. To extend our previous work in which we found that doxycycline, which has multiple effects on mammalian cells, improves motor behavior and more than doubles the median life-span of Lama2−/− mice, we also determined how nerve pathology was affected by doxycycline treatment. We found that myelinating (Krox20+) Schwann cells were significantly increased in doxycycline-treated compared with untreated sciatic nerves. In addition, doxycycline-treated peripheral nerves had significantly less pathology as measured by assays such as amount of unmyelinated or disorganized axons. This study thus identified aberrant proliferation and differentiation of Schwann cells as key components of pathogenesis in peripheral nerves and provided proof-of-concept that pharmaceutical therapy can be of potential benefit for peripheral nerve dysfunction in MDC1A. PMID:21505075

A web-based GPS system for displacement monitoring and failure mechanism analysis of reservoir landslide.

PubMed

Li, Yuanyao; Huang, Jinsong; Jiang, Shui-Hua; Huang, Faming; Chang, Zhilu

2017-12-07

It is important to monitor the displacement time series and to explore the failure mechanism of reservoir landslide for early warning. Traditionally, it is a challenge to monitor the landslide displacements real-timely and automatically. Globe Position System (GPS) is considered as the best real-time monitoring technology, however, the accuracies of the landslide displacements monitored by GPS are not assessed effectively. A web-based GPS system is developed to monitor the landslide displacements real-timely and automatically in this study. And the discrete wavelet transform (DWT) is proposed to assess the accuracy of the GPS monitoring displacements. Wangmiao landslide in Three Gorges Reservoir area in China is used as case study. The results show that the web-based GPS system has advantages of high precision, real-time, remote control and automation for landslide monitoring; the Root Mean Square Errors of the monitoring landslide displacements are less than 5 mm. Meanwhile, the results also show that a rapidly falling reservoir water level can trigger the reactivation of Wangmiao landslide. Heavy rainfall is also an important factor, but not a crucial component.

Effects of antidromic stimulation of the ventral root on glucose utilization in the ventral horn of the spinal cord in the rat.

PubMed Central

Kadekaro, M; Vance, W H; Terrell, M L; Gary, H; Eisenberg, H M; Sokoloff, L

1987-01-01

Electrical stimulation of the proximal stump of the transected sciatic nerve increased glucose utilization in the ventral horn of the spinal cord, with the greater increase in Rexed's lamina IX. Antidromic stimulation of the ventral root, however, did not change glucose utilization in the ventral horn. These results suggest that the axon terminals and not the cell bodies are the sites of enhanced metabolic activity during increased electrical activity in these elements. Images PMID:3474665

The Sihler staining study of the infraorbital nerve and its clinical complication.

PubMed

Yang, Hun-Mu; Won, Sung-Yoon; Lee, Young-Il; Kim, Hee-Jin; Hu, Kyung-Seok

2014-11-01

The infraorbital nerve (ION) is a cardinal cutaneous nerve that provides general sensation to the mid face. Its twigs are vulnerable to iatrogenic damage during medical and dental manipulations. The aims of this study were to elucidate the distribution pattern of the ION and thus help to prevent nerve damage during medical procedures and to enable accurate prognostic evaluation where complications do occur. This was achieved by treating 7 human hemifaces with the Sihler modified staining protocol, which enables clear visualization of the course and distribution of nerves without the accidental displacement of these structures that can occur during classic dissection. The twigs of the ION can be classified into the usual 5 groups: inferior palpebral, innervating the lower eyelid in a fan-shaped area; external and internal nasal, reaching the nosewing and philtrum including the septal area between the nostrils, respectively; as well as medial and lateral superior labial, supplying the superior labial area from the midline to the mouth corner. Of particular note, the superior labial twigs fully innervated the infraorbital triangle formed by the infraorbital foramen, the most lateral point of the nosewing, and the mouth corner. In the superior 3-quarter area, the ION twigs made anastomoses with the buccal branches of the facial nerve, forming an infraorbital nervous plexus. The infraorbital triangle may be considered a dangerous zone with respect to the risk for iatrogenic complications associated with the various medical interventions such as implant placement.

Hindlimb spasticity after unilateral motor cortex lesion in rats is reduced by contralateral nerve root transfer.

PubMed

Zong, Haiyang; Ma, Fenfen; Zhang, Laiyin; Lu, Huiping; Gong, Jingru; Cai, Min; Lin, Haodong; Zhu, Yizhun; Hou, Chunlin

2016-12-01

Lower extremity spasticity is a common sequela among patients with acquired brain injury. The optimum treatment remains controversial. The aim of our study was to test the feasibility and effectiveness of contralateral nerve root transfer in reducing post stroke spasticity of the affected hindlimb muscles in rats. In our study, we for the first time created a novel animal hindlimb spastic hemiplegia model in rats with photothrombotic lesion of unilateral motor cortex and we established a novel surgical procedure in reducing motor cortex lesion-induced hindlimb spastic hemiplegia in rats. Thirty six rats were randomized into three groups. In group A, rats received sham operation. In group B, rats underwent unilateral hindlimb motor cortex lesion. In group C, rats underwent unilateral hindlimb cortex lesion followed by contralateral L4 ventral root transfer to L5 ventral root of the affected side. Footprint analysis, Hoffmann reflex (H-reflex), cholera toxin subunit B (CTB) retrograde tracing of gastrocnemius muscle (GM) motoneurons and immunofluorescent staining of vesicle glutamate transporter 1 (VGLUT1) on CTB-labelled motoneurons were used to assess spasticity of the affected hindlimb. Sixteen weeks postoperatively, toe spread and stride length recovered significantly in group C compared with group B (P<0.001). H max (H-wave maximum amplitude)/M max (M-wave maximum amplitude) ratio of gastrocnemius and plantaris muscles (PMs) significantly reduced in group C (P<0.01). Average VGLUT1 positive boutons per CTB-labelled motoneurons significantly reduced in group C (P<0.001). We demonstrated for the first time that contralateral L4 ventral root transfer to L5 ventral root of the affected side was effective in relieving unilateral motor cortex lesion-induced hindlimb spasticity in rats. Our data indicated that this could be an alternative treatment for unilateral lower extremity spasticity after brain injury. Therefore, contralateral neurotization may exert a potential therapeutic candidate to improve the function of lower extremity in patients with spastic hemiplegia. © 2016 The Author(s).

Early blindness and coma during intrathecal chemotherapy for meningeal carcinomatosis.

PubMed

Boogerd, W; Moffie, D; Smets, L A

1990-02-01

A 35-year-old woman was treated with intraventricular methotrexate (MTX) with a total dose of 70 mg followed by cytosine arabinoside (Ara-C) with a total dose of 80 mg for meningeal metastasis of breast carcinoma. Radiation therapy was not given. Despite a response of the meningeal tumor the patient developed in the third week of MTX treatment a progressive visual loss and loss of consciousness which worsened during subsequent Ara-C treatment and led to death within 3 weeks. Postmortem examination revealed only minimal neoplastic infiltration of the meninges. Multiple foci of axonal degeneration and demyelination were found in the optic nerves and chiasm, the superficial layers of the brainstem, and spinal cord and to some extent in other cranial nerves and spinal nerve roots. The possible causes of this previously unreported early complication are discussed.

Receiver operating characteristic analysis. Application to the study of quantum fluctuation effects in optic nerve of Rana pipiens

PubMed Central

1975-01-01

Receiver operating characteristic (ROC) analysis of nerve messages is described. The hypothesis that quantum fluctuations provide the only limit to the ability of frog ganglion cells to signal luminance change information is examined using ROC analysis. In the context of ROC analysis, the quantum fluctuation hypothesis predicts (a) the detectability of a luminance change signal should rise proportionally to the size of the change, (b) detectability should decrease as the square root of background, an implication of which is the deVries-Rose law, and (c) ROC curves should exhibit a shape particular to underlying Poisson distributions. Each of these predictions is confirmed for the responses of dimming ganglion cells to brief luminance decrements at scotopic levels, but none could have been tested using classical nerve message analysis procedures. PMID:172597

High-speed passenger rail tie-ballast interaction.

DOT National Transportation Integrated Search

2015-05-01

This Research Results Report presents : evidence of poor tie support and increased : applied loads that were used to determine the : root cause of transient and permanent vertical : displacements at two Amtrak bridge transitions. : These result...

Microstructural changes are coincident with the improvement of clinical symptoms in surgically treated compressed nerve roots

PubMed Central

Wu, Weifei; Liang, Jie; Chen, Ying; Chen, Aihua; Wu, Yongde; Yang, Zong

2017-01-01

Diffusion tensor imaging (DTI) has been widely used to visualize peripheral nerves, but the microstructure of compressed nerve roots can be assessed using DTI. However, there are no data regarding the association among microstructural changes evaluated using DTI, the symptoms assessed using the Oswestry Disability Index (ODI) and the duration of symptoms after surgery in patients with lumbar disc herniation (LDH). Thirty patients with unilateral radiculopathy were investigated using DTI. The changes in the mean fractional anisotropy (FA) and the apparent diffusion coefficient (ADC) values as well as the correlation between these changes and the severity and duration of the clinical symptoms were investigated before and at least one month after surgery. The FA values were significantly increased after surgical treatment (p < 0.0001). Both the ADC and ODI values were noticeably decreased (p < 0.0001). A strong positive correlation between the preoperative and postoperative DTI parameters (p < 0.0001) as well as between the preoperative ODI and postoperative ODI/ODI changes (p < 0.0001) were found. In addition, there was a significant positive correlation between the changes in the DTI parameters and changes in the ODI (p < 0.0001). This preliminary study suggests it may be possible to use DTI to diagnose, quantitatively evaluate and follow-up patients with LDH. PMID:28294192

The transcription factor C/EBPβ in the dorsal root ganglion contributes to peripheral nerve trauma–induced nociceptive hypersensitivity

PubMed Central

Li, Zhisong; Mao, Yuanyuan; Liang, Lingli; Wu, Shaogen; Yuan, Jingjing; Mo, Kai; Cai, Weihua; Mao, Qingxiang; Cao, Jing; Bekker, Alex; Zhang, Wei; Tao, Yuan-Xiang

2017-01-01

Changes in gene transcription in the dorsal root ganglion (DRG) after nerve trauma contribute to the genesis of neuropathic pain. We report that peripheral nerve trauma caused by chronic constriction injury (CCI) increased the abundance of the transcription factor C/EBPβ (CCAAT/enhancer binding protein β) in the DRG. Blocking this increase mitigated the development and maintenance of CCI-induced mechanical, thermal, and cold pain hypersensitivities without affecting basal responses to acute pain and locomotor activity. Conversely, mimicking this increase produced hypersensitivity to mechanical, thermal, or cold pain. In the ipsilateral DRG, C/EBPβ promoted a decrease in the abundance of the voltage-gated potassium channel subunit Kv1.2 and µ opioid receptor (MOR) at the mRNA and protein levels, which would be predicted to increase excitability in the ipsilateral DRG neurons and reduce the efficacy of morphine analgesia. These effects required C/EPBβ-mediated transcriptional activation of Ehmt2 (euchromatic histonelysine N-methyltransferase 2), which encodes G9a, an epigenetic silencer of the genes encoding Kv1.2 and MOR. Blocking the increase in C/EBPβ in the DRG improved morphine analgesia after CCI. These results suggest that C/EBPβ is an endogenous initiator of neuropathic pain and could be a potential target for the prevention and treatment of this disorder. PMID:28698219

Origins, actions and dynamic expression patterns of the neuropeptide VGF in rat peripheral and central sensory neurones following peripheral nerve injury

PubMed Central

Moss, Andrew; Ingram, Rachel; Koch, Stephanie; Theodorou, Andria; Low, Lucie; Baccei, Mark; Hathway, Gareth J; Costigan, Michael; Salton, Stephen R; Fitzgerald, Maria

2008-01-01

Background The role of the neurotrophin regulated polypeptide, VGF, has been investigated in a rat spared injury model of neuropathic pain. This peptide has been shown to be associated with synaptic strengthening and learning in the hippocampus and while it is known that VGFmRNA is upregulated in dorsal root ganglia following peripheral nerve injury, the role of this VGF peptide in neuropathic pain has yet to be investigated. Results Prolonged upregulation of VGF mRNA and protein was observed in injured dorsal root ganglion neurons, central terminals and their target dorsal horn neurons. Intrathecal application of TLQP-62, the C-terminal active portion of VGF (5–50 nmol) to naïve rats caused a long-lasting mechanical and cold behavioral allodynia. Direct actions of 50 nM TLQP-62 upon dorsal horn neuron excitability was demonstrated in whole cell patch recordings in spinal cord slices and in receptive field analysis in intact, anesthetized rats where significant actions of VGF were upon spontaneous activity and cold evoked responses. Conclusion VGF expression is therefore highly modulated in nociceptive pathways following peripheral nerve injury and can cause dorsal horn cell excitation and behavioral hypersensitivity in naïve animals. Together the results point to a novel and powerful role for VGF in neuropathic pain. PMID:19077191

Neurofibromas of the Phrenic Nerve: A Case Report and Review of the Literature.

PubMed

Ghali, Michael G Z; Srinivasan, Visish M; Jea, Andrew; Slopis, John M; McCutcheon, Ian E

2016-04-01

Phrenic neurofibromas are a rare pathologic entity, with 9 cases described in the English literature. They may occur in conjunction with or independently of neurofibromatosis type 1. Phrenic neurofibromas pose distinct therapeutic challenges compared with the more common phrenic schwannoma. We describe here a 12-year-old boy with neurofibroma of the left phrenic nerve presenting as dextroposition of the heart after paralysis of the left hemidiaphragm allowed herniation of abdominal contents into the left hemithorax and displaced the heart. Surgical resection of the tumor followed by diaphragmatic plication was performed to assess its degree of malignancy, reduce abdominal herniation, and improve lung capacity. The operation markedly improved his hemidiaphragmatic elevation. The spectrum of management options ranges from conservative surveillance to open thoracic surgery. Functional preservation of the phrenic nerve is technically challenging, and although phrenic neurofibromas often present with absent function that cannot be recovered, surgical intervention can be fruitful in restoring lung capacity through diaphragmatic reconstruction. Copyright © 2016 Elsevier Inc. All rights reserved.

Orbital nerve seath myxoma with extraocular muscle involvement: a rare case.

PubMed

Rodríguez-Uña, Ignacio; Troyano-Rivas, Juan A; González-García, Cristina; Chícharo-de-Freitas, Reinaldo; Ortiz-Zapata, Juan J; Ortega-Medina, Luis; Toledano-Fernández, Nicolás; García-Feijoo, Julián

2015-07-01

A 66-year-old woman with breast cancer presented with a painless mass in the left orbit. MRI revealed a well-defined intraconal mass in the temporal quadrant of the orbit. Fifteen months later, a further MRI indicated the mass had grown, displacing the left optic nerve and making contact with the lateral rectus muscle, suggesting its possible intramuscular origin. Despite the clinical and radiological characteristics of the lesion and its slow growth, a PET/CT study was developed because of the history of malignant disease. No metabolic activity of the mass or malignant lesion in other locations was observed. After surgical excision, histopathological examination revealed an abundant myxoid matrix with few spindle-shaped cells and no signs of malignancy. The cells were immunopositive for CD34, positive for S-100 protein, and negative for EMA, actin, and CD57. A diagnosis was made of a nerve sheath myxoma. The orbital location of these tumors is extremely rare.

High-resolution anatomy of the human brain stem using 7-T MRI: improved detection of inner structures and nerves?

PubMed

Gizewski, Elke R; Maderwald, Stefan; Linn, Jennifer; Dassinger, Benjamin; Bochmann, Katja; Forsting, Michael; Ladd, Mark E

2014-03-01

The purpose of this paper is to assess the value of 7 Tesla (7 T) MRI for the depiction of brain stem and cranial nerve (CN) anatomy. Six volunteers were examined at 7 T using high-resolution SWI, MPRAGE, MP2RAGE, 3D SPACE T2, T2, and PD images to establish scanning parameters targeted at optimizing spatial resolution. Direct comparisons between 3 and 7 T were performed in two additional subjects using the finalized sequences (3 T: T2, PD, MPRAGE, SWAN; 7 T: 3D T2, MPRAGE, SWI, MP2RAGE). Artifacts and the depiction of structures were evaluated by two neuroradiologists using a standardized score sheet. Sequences could be established for high-resolution 7 T imaging even in caudal cranial areas. High in-plane resolution T2, PD, and SWI images provided depiction of inner brain stem structures such as pons fibers, raphe, reticular formation, nerve roots, and periaqueductal gray. MPRAGE and MP2RAGE provided clear depiction of the CNs. 3D T2 images improved depiction of inner brain structure in comparison to T2 images at 3 T. Although the 7-T SWI sequence provided improved contrast to some inner structures, extended areas were influenced by artifacts due to image disturbances from susceptibility differences. Seven-tesla imaging of basal brain areas is feasible and might have significant impact on detection and diagnosis in patients with specific diseases, e.g., trigeminal pain related to affection of the nerve root. Some inner brain stem structures can be depicted at 3 T, but certain sequences at 7 T, in particular 3D SPACE T2, are superior in producing anatomical in vivo images of deep brain stem structures.

HMG-CoA synthase isoenzymes 1 and 2 localize to satellite glial cells in dorsal root ganglia and are differentially regulated by peripheral nerve injury.

PubMed

Wang, Fei; Xiang, Hongfei; Fischer, Gregory; Liu, Zhen; Dupont, Matthew J; Hogan, Quinn H; Yu, Hongwei

2016-12-01

In dorsal root ganglia (DRG), satellite glial cells (SGCs) tightly ensheathe the somata of primary sensory neurons to form functional sensory units. SGCs are identified by their flattened and irregular morphology and expression of a variety of specific marker proteins. In this report, we present evidence that the 3-hydroxy-3-methylglutaryl coenzyme A synthase isoenzymes 1 and 2 (HMGCS1 and HMGCS2) are abundantly expressed in SGCs. Immunolabeling with the validated antibodies revealed that both HMGCS1 and HMGCS2 are highly colabeled with a selection of SGC markers, including GS, GFAP, K ir 4.1, GLAST1, GDNF, and S100 but not with microglial cell marker Iba1, myelin sheath marker MBP, and neuronal marker β3-tubulin or phosphorylated CaMKII. HMGCS1 but not HMGCS2 immunoreactivity in SGCs is reduced in the fifth lumbar (L5) DRGs that contain axotomized neurons following L5 spinal nerve ligation (SNL) in rats. Western blot showed that HMGCS1 protein level in axotomized L5 DRGs is reduced after SNL to 66±8% at 3 days (p<0.01, n=4 animals in each group) and 58±13% at 28 days (p<0.001, n=9 animals in each group) of its level in control samples, whereas HMGCS2 protein was comparable between injured and control DRGs. These results identify HMGCSs as the alternative markers for SGCs in DRGs. Downregulated HMGCS1 expression in DRGs after spinal nerve injury may reflect a potential role of abnormal sterol metabolism of SGCs in the nerve injured-induced neuropathic pain. Copyright © 2016 Elsevier B.V. All rights reserved.

Multimodal intraoperative monitoring: an overview and proposal of methodology based on 1,017 cases

PubMed Central

Eggspuehler, Andreas; Muller, Alfred; Dvorak, Jiri

2007-01-01

To describe different currently available tests of multimodal intraoperative monitoring (MIOM) used in spine and spinal cord surgery indicating the technical parameters, application and interpretation as an easy understanding systematic overview to help implementation of MIOM and improve communication between neurophysiologists and spine surgeons. This article aims to give an overview and proposal of the different MIOM-techniques as used daily in spine and spinal cord surgery at our institution. Intensive research in neurophysiology over the past decades has lead to a profound understanding of the spinal cord, nerve functions and their intraoperative functional evaluation in anaesthetised patients. At present, spine surgeons and neurophysiologist are faced with 1,883 publications in PubMed on spinal cord monitoring. The value and the limitations of single monitoring methods are well documented. The diagnostic power of the multimodal approach in a larger study population in spine surgery, as measured with sensitivity and specificity, is dealt with elsewhere in this supplement (Sutter et al. in Eur Spine J Suppl, 2007). This paper aims to give a detailed description of the different modalities used in this study. Description of monitoring techniques of the descending and ascending spinal cord and nerve root pathways by motor evoked potentials of the spinal cord and muscles elicited after transcranial electrical motor cortex, spinal cord, cauda equina and nerve root stimulation, continuous EMG, sensory cortical and spinal evoked potentials, as well as direct spinal cord evoked potentials applied on 1,017 patients. The method of MIOM, continuously adapted according to the site, stage of surgery and potential danger to nerve tissues, proved to be applicable with online results, reliable and furthermore teachable. PMID:17653777

Neurogenin 1 Null Mutant Ears Develop Fewer, Morphologically Normal Hair Cells in Smaller Sensory Epithelia Devoid of Innervation

PubMed Central

Ma, Qiufu; Anderson, David J.

2000-01-01

The proneuronal gene neurogenin 1 (ngn1) is essential for development of the inner-ear sensory neurons that are completely absent in ngn1 null mutants. Neither afferent, efferent, nor autonomic nerve fibers were detected in the ears of ngn1 null mutants. We suggest that efferent and autonomic fibers are lost secondarily to the absence of afferents. In this article we show that ngn1 null mutants develop smaller sensory epithelia with morphologically normal hair cells. In particular, the saccule is reduced dramatically and forms only a small recess with few hair cells along a duct connecting the utricle with the cochlea. Hair cells of newborn ngn1 null mutants show no structural abnormalities, suggesting that embryonic development of hair cells is independent of innervation. However, the less regular pattern of dispersal within sensory epithelia may be caused by some effects of afferents or to the stunted growth of the sensory epithelia. Tracing of facial and stato-acoustic nerves in control and ngn1 null mutants showed that only the distal, epibranchial, placode-derived sensory neurons of the geniculate ganglion exist in mutants. Tracing further showed that these geniculate ganglion neurons project exclusively to the solitary tract. In addition to the normal complement of facial branchial and visceral motoneurons, ngn1 null mutants have some trigeminal motoneurons and contralateral inner-ear efferents projecting, at least temporarily, through the facial nerve. These data suggest that some neurons in the brainstem (e.g., inner-ear efferents, trigeminal motoneurons) require afferents to grow along and redirect to ectopic cranial nerve roots in the absence of their corresponding sensory roots. PMID:11545141

μ-Opioid receptor inhibition of substance P release from primary afferents disappears in neuropathic pain but not inflammatory pain

PubMed Central

Chen, Wenling; McRoberts, James A.; Marvizón, Juan Carlos G.

2014-01-01

Opiate analgesia in the spinal cord is impaired during neuropathic pain. We hypothesized that this is caused by a decrease in μ-opioid receptor inhibition of neurotransmitter release from primary afferents. To investigate this possibility, we measured substance P release in the spinal dorsal horn as neurokinin 1 receptor (NK1R) internalization in rats with chronic constriction injury (CCI) of the sciatic nerve. Noxious stimulation of the paw with CCI produced inconsistent NK1R internalization, suggesting that transmission of nociceptive signals by the injured nerve was variably impaired after CCI. This idea was supported by the fact that CCI produced only small changes in the ability of exogenous substance P to induce NK1R internalization or in the release of substance P evoked centrally from site of nerve injury. In subsequent experiments, NK1R internalization was induced in spinal cord slices by stimulating the dorsal root ipsilateral to CCI. We observed a complete loss of the inhibition of substance P release by the μ-opioid receptor agonist [D-Ala2, NMe-Phe4, Gly-ol5]-enkephalin (DAMGO) in CCI rats but not in sham-operated rats. In contrast, DAMGO still inhibited substance P release after inflammation of the hind paw with complete Freund’s adjuvant and in naïve rats. This loss of inhibition was not due to μ-opioid receptor downregulation in primary afferents, because their colocalization with substance P was unchanged, both in dorsal root ganglion neurons and primary afferent fibers in the dorsal horn. In conclusion, nerve injury eliminates the inhibition of substance P release by μ-opioid receptors, probably by hindering their signaling mechanisms. PMID:24583035

μ-Opioid receptor inhibition of substance P release from primary afferents disappears in neuropathic pain but not inflammatory pain.

PubMed

Chen, W; McRoberts, J A; Marvizón, J C G

2014-05-16

Opiate analgesia in the spinal cord is impaired during neuropathic pain. We hypothesized that this is caused by a decrease in μ-opioid receptor inhibition of neurotransmitter release from primary afferents. To investigate this possibility, we measured substance P release in the spinal dorsal horn as neurokinin 1 receptor (NK1R) internalization in rats with chronic constriction injury (CCI) of the sciatic nerve. Noxious stimulation of the paw with CCI produced inconsistent NK1R internalization, suggesting that transmission of nociceptive signals by the injured nerve was variably impaired after CCI. This idea was supported by the fact that CCI produced only small changes in the ability of exogenous substance P to induce NK1R internalization or in the release of substance P evoked centrally from site of nerve injury. In subsequent experiments, NK1R internalization was induced in spinal cord slices by stimulating the dorsal root ipsilateral to CCI. We observed a complete loss of the inhibition of substance P release by the μ-opioid receptor agonist [D-Ala(2), NMe-Phe(4), Gly-ol(5)]-enkephalin (DAMGO) in CCI rats but not in sham-operated rats. In contrast, DAMGO still inhibited substance P release after inflammation of the hind paw with complete Freund's adjuvant and in naïve rats. This loss of inhibition was not due to μ-opioid receptor downregulation in primary afferents, because their colocalization with substance P was unchanged, both in dorsal root ganglion neurons and primary afferent fibers in the dorsal horn. In conclusion, nerve injury eliminates the inhibition of substance P release by μ-opioid receptors, probably by hindering their signaling mechanisms. Published by Elsevier Ltd.

Effect of noxious electrical stimulation of the peroneal nerve on stretch reflex activity of the hamstring muscle in rats: possible implications of neuronal mechanisms in the development of tight hamstrings in lumbar disc herniation.

PubMed

Hirayama, Jiro; Yamagata, Masatsune; Takahashi, Kazuhisa; Moriya, Hideshige

2005-05-01

The effect of noxious electrical stimulation of the peroneal nerve on the stretch reflex electromyogram activity of the hamstring muscle (semitendinous) was studied. To verify the following hypothetical mechanisms underlying tight hamstrings in lumbar disc herniation: stretch reflex muscle activity of hamstrings is increased by painful inputs from an injured spinal nerve root and the increased stretch reflex muscle activity is maintained by central sensitization. It is reported that stretch reflex activity of the trunk muscles is induced by noxious stimulation of the sciatic nerve and maintained by central sensitization. In spinalized rats (transected spinal cord), the peroneal nerve was stimulated electrically as a conditioning stimulus. Stretch reflex electromyogram activity of the semitendinous muscle was recorded before and after the conditioning stimulus. Even after electrical stimulation was terminated, an increased stretch reflex activity of the hamstring muscle was observed. It is likely that a central sensitization mechanism at the spinal cord level was involved in the increased reflex activity. Central sensitization may play a part in the neuronal mechanisms of tight hamstrings in lumbar disc herniation.

MRI-guided Focused Ultrasound Ablation of Lumbar Medial Branch Nerve: Feasibility and Safety Study in a Swine Model

PubMed Central

Kaye, Elena A; Monette, Sebastien; Srimathveeravalli, Govindarajan; Maybody, Majid; Solomon, Stephen B; Gulati, Amitabh

2016-01-01

Purpose About 10–40% of chronic low back pain cases involve facet joints, which are commonly treated with lumbar medial branch (MB) radiofrequency neurotomy. Magnetic Resonance Imaging-guided Focused Ultrasound (MRgFUS), a non-invasive, non-ionizing ablation modality used to treat tumors, neuropathic pain and painful bone metastasis, can also be used to disrupt nerve conduction. This work’s purpose was to study the feasibility and safety of direct MRgFUS ablation of the lumbar MB nerve in acute and subacute swine models. Materials and Methods In vivo MRgFUS ablation was performed in six swine (3 acute and 3 subacute) using a clinical MRgFUS system (ExAblate 2000®; InSightec Ltd., Haifa, Israel) and 3 T MRI scanner (SIGNA; GE Healthcare, Waukesha, WI, USA) combination. Behavioral assessment was performed, and imaging and histology were used to assess the treatment. Results and Conclusions Histological analysis of the in vivo studies confirmed thermal necrosis of the MB nerve could be achieved without damaging the spinal cord or adjacent nerve roots. MRgFUS did not cause changes in the animals’ behavior and ambulation. PMID:27443328

Schwann cells induce cancer cell dispersion and invasion

PubMed Central

Deborde, Sylvie; Lyubchik, Anna; Zhou, Yi; He, Shizhi; McNamara, William F.; Chernichenko, Natalya; Lee, Sei-Young; Barajas, Fernando; Chen, Chun-Hao; Bakst, Richard L.; Vakiani, Efsevia; He, Shuangba; Hall, Alan; Wong, Richard J.

2016-01-01

Nerves enable cancer progression, as cancers have been shown to extend along nerves through the process of perineural invasion, which carries a poor prognosis. Furthermore, the innervation of some cancers promotes growth and metastases. It remains unclear, however, how nerves mechanistically contribute to cancer progression. Here, we demonstrated that Schwann cells promote cancer invasion through direct cancer cell contact. Histological evaluation of murine and human cancer specimens with perineural invasion uncovered a subpopulation of Schwann cells that associates with cancer cells. Coculture of cancer cells with dorsal root ganglion extracts revealed that Schwann cells direct cancer cells to migrate toward nerves and promote invasion in a contact-dependent manner. Upon contact, Schwann cells induced the formation of cancer cell protrusions in their direction and intercalated between the cancer cells, leading to cancer cell dispersion. The formation of these processes was dependent on Schwann cell expression of neural cell adhesion molecule 1 (NCAM1) and ultimately promoted perineural invasion. Moreover, NCAM1-deficient mice showed decreased neural invasion and less paralysis. Such Schwann cell behavior reflects normal Schwann cell programs that are typically activated in nerve repair but are instead exploited by cancer cells to promote perineural invasion and cancer progression. PMID:26999607

Activation of the unfolded protein response promotes axonal regeneration after peripheral nerve injury.

PubMed

Oñate, Maritza; Catenaccio, Alejandra; Martínez, Gabriela; Armentano, Donna; Parsons, Geoffrey; Kerr, Bredford; Hetz, Claudio; Court, Felipe A

2016-02-24

Although protein-folding stress at the endoplasmic reticulum (ER) is emerging as a driver of neuronal dysfunction in models of spinal cord injury and neurodegeneration, the contribution of this pathway to peripheral nerve damage remains poorly explored. Here we targeted the unfolded protein response (UPR), an adaptive reaction against ER stress, in mouse models of sciatic nerve injury and found that ablation of the transcription factor XBP1, but not ATF4, significantly delay locomotor recovery. XBP1 deficiency led to decreased macrophage recruitment, a reduction in myelin removal and axonal regeneration. Conversely, overexpression of XBP1s in the nervous system in transgenic mice enhanced locomotor recovery after sciatic nerve crush, associated to an improvement in key pro-regenerative events. To assess the therapeutic potential of UPR manipulation to axonal regeneration, we locally delivered XBP1s or an shRNA targeting this transcription factor to sensory neurons of the dorsal root ganglia using a gene therapy approach and found an enhancement or reduction of axonal regeneration in vivo, respectively. Our results demonstrate a functional role of specific components of the ER proteostasis network in the cellular changes associated to regeneration and functional recovery after peripheral nerve injury.

Activation of the unfolded protein response promotes axonal regeneration after peripheral nerve injury

PubMed Central

Oñate, Maritza; Catenaccio, Alejandra; Martínez, Gabriela; Armentano, Donna; Parsons, Geoffrey; Kerr, Bredford; Hetz, Claudio; Court, Felipe A.

2016-01-01

Although protein-folding stress at the endoplasmic reticulum (ER) is emerging as a driver of neuronal dysfunction in models of spinal cord injury and neurodegeneration, the contribution of this pathway to peripheral nerve damage remains poorly explored. Here we targeted the unfolded protein response (UPR), an adaptive reaction against ER stress, in mouse models of sciatic nerve injury and found that ablation of the transcription factor XBP1, but not ATF4, significantly delay locomotor recovery. XBP1 deficiency led to decreased macrophage recruitment, a reduction in myelin removal and axonal regeneration. Conversely, overexpression of XBP1s in the nervous system in transgenic mice enhanced locomotor recovery after sciatic nerve crush, associated to an improvement in key pro-regenerative events. To assess the therapeutic potential of UPR manipulation to axonal regeneration, we locally delivered XBP1s or an shRNA targeting this transcription factor to sensory neurons of the dorsal root ganglia using a gene therapy approach and found an enhancement or reduction of axonal regeneration in vivo, respectively. Our results demonstrate a functional role of specific components of the ER proteostasis network in the cellular changes associated to regeneration and functional recovery after peripheral nerve injury. PMID:26906090

Effects of Chemically Doped Bioactive Borate Glass on Neuron Regrowth and Regeneration.

PubMed

Gupta, Brinda; Papke, Jason B; Mohammadkhah, Ali; Day, Delbert E; Harkins, Amy B

2016-12-01

Peripheral nerve injuries present challenges to regeneration. Currently, the gold standard for nerve repair is an autograft that results in another region of the body suffering nerve damage. Previously, bioactive borate glass (BBG) has been studied in clinical trials to treat patients with non-healing wounds, and we have reported that BBG is conducive for soft tissue repair. BBG provides structural support, degrades in a non-cytotoxic manner, and can be chemically doped. Here, we tested a wide range of chemical compounds that are reported to have neuroprotective characteristics to promote regeneration of peripheral neurons after traumatic injury. We hypothesized that chemical dopants added in trace amounts to BBG would improve neuronal survival and neurite outgrowth from dorsal root ganglion (DRG) explants. We measured neurite outgrowth from whole DRG explants, and survival rates of dissociated neurons and support cells that comprise the DRG. Results show that chemically doped BBGs have differentially variable effects on neuronal survival and outgrowth, with iron, gallium, and zinc improving outgrowth of neurons, and iodine causing the most detriment to neurons. Because chemically doped BBGs support increased nerve regrowth and survival, they show promise for use in peripheral nerve regeneration.

Closed Versus Open Supracondylar Fractures of the Humerus in Children: A Comparison of Clinical and Radiographic Presentation and Results.

PubMed

Lewine, Eliza; Kim, Jaehon M; Miller, Patricia E; Waters, Peter M; Mahan, Susan T; Snyder, Brian; Hedequist, Daniel; Bae, Donald S

2018-02-01

The purpose of this investigation was to compare the presentation and postoperative results of children treated for open and closed, completely displaced type III supracondylar humerus fractures (SCFs). Thirty patients with open and 66 patients with closed, completely displaced type III SCFs were evaluated. Open fractures underwent irrigation and debridement, and all patients were treated by open or closed reduction and pin fixation. Medical records were reviewed to obtain demographic information as well as preoperative and postoperative clinical data regarding mechanism of injury, neurovascular status, associated injuries, postoperative range of motion, infections, and pain. Radiographs were evaluated to quantify displacement, Baumann's angle, humeral capitellar angle, position of the anterior humeral line, and adequacy of reduction. Outcomes were assessed using Flynn criteria. Mean clinical follow-up for the open and closed fracture groups was 8.9 and 5.7 months, respectively. Both groups were similar with respect to age, sex distribution, weight and body mass index, laterality of involvement, and mechanism of injury. At presentation, 35% of closed SCFs and 23% of open SCFs presented with abnormal neurovascular status. There was a higher prevalence of diminished/absent pulses or distal limb ischemia in patients with open injuries (27%) compared with closed fractures (18%). Conversely, severely displaced closed fractures were more commonly associated with nerve injury/palsy at presentation (35%) than those with open fractures (23%). Spontaneous nerve recovery was seen in 87% within 3 to 6 months. Postoperative loss of reduction and malunion were more common in the closed fracture group. However, 84% of patients achieved good-to-excellent results by Flynn criteria, with no appreciable difference based upon open versus closed fractures. With timely wound and fracture treatment, the clinical and radiographic results of children treated for open SCFs is similar to those with closed type III injuries, with little increased risk for infection, malunion, or neurovascular compromise. Level III.

Experiments on Laser Beam Jitter Control with Applications to a Shipboard Free Electron Laser

DTIC Science & Technology

2007-12-01

factor one half converts from peak to rms values. This psd was then converted to units of ( mrms /s2)2/Hz by dividing by the square of the given voltage...the root mean square value in units of mrms for a given frequency range. (3) Vibration Measurement Results. The total displacement from 1-400 Hz...The mass may represent, for example, a component of an FEL. The support, s, is harmonically excited at a peak displacement amplitude of xs. The

Ultrastructure of pea and cress root statocytes exposed to high gradient magnetic field

NASA Astrophysics Data System (ADS)

Belyavskaya, N. A.; Chernishov, V. I.; Polishchuk, O. V.; Kondrachuk, A. V.

As it was demonstrated by Kuznetsov & Hasenstein (1996) the high gradient magnetic field (HGMF) can produce a ponderomotive force that results in displacements of amyloplasts and causes the root response similar to the graviresponse. It was suggested that the HGMF could allow to imitate the effects of gravity in microgravity and/or change them in laboratory conditions correspondingly, as well as to study statolith-related processes in graviperception. Therefore, the correlation between the direction of the ponderomotive force resulting in statolith displacements and the direction of the HGMF-induced plant curvature can be the serious argument to support this suggestion and needs the detailed ultrastructural analysis. Seeds of dicotyledon Pisum sativum L. cv. Damir-2 and monocotyledon Lepidium sativum L. cv. P896 were soaked and grown in a vertical position on moist filter paper in chambers at room temperature. Tips of primary roots of vertical control, gravistimulated and exposed to HGMF seedlings were fixed for electron microscopy using conventional techniques. At ultrastructural level, we observed no significant changes in the volume of the individual statocytes or amyloplasts, relative volumes of cellular organelles (except vacuoles), number of amyloplasts per statocyte or surface area of endoplasmic reticulum. No consistent contacts between amyloplasts and any cellular structures, including plasma membrane, were revealed at any stage of magneto- and gravistimulation. By 5 min after onset of magnetostimulation, amyloplasts were located along cell wall distant from magnets. In HGMF, the locations of amyloplasts in columella cells were similar to those in horizontally-oriented roots up to 1 h stimulation. In the latter case, there were sometimes cytoplasmic spherical bodies with a dense vesicle-rich cytoplasm in pea statocytes, which were absent in seedlings exposed to HGMF. In cress root statocytes, both gravi- and magnetostimulation were found to cause the appearance of significant amounts of electron-dense granules in the cytoplasm and the nucleus (particularly, in the nucleolus); the effect was most evident in HGMF. Testing the chemical composition of such deposits is going on. The data presented statocyte responses indicate similarity the effects of magneto- and gravistimulation at the ultrastructural level. Thus, the root curvature in HGMF is the plant response to displacement of amyloplasts by ponderomotive force, which can serve as tool for investigation of graviperception mechanism and can provide directional stimulus for plant growth in microgravity. (Financial support by STCU: NN-13R).

Tibial avulsion fracture of the posterior root of the medial meniscus in children.

PubMed

Iversen, Jonas Vestergård; Krogsgaard, Michael Rindom

2014-01-01

Few reports have described avulsion fractures of the posterior root of the medial meniscus in skeletally immature patients. This lesion should not be overlooked as it damages the load absorptive (distributive) function of the meniscus, increasing the risk of cartilage degeneration. Two cases of displaced avulsion fractures of the posterior root of the medial meniscus in children are presented along with a concise report of the literature regarding avulsion fractures of the posterior root of the medial meniscus. Both avulsions were reattached arthroscopically by trans-tibial pull-out sutures with a good clinical result at 2-years follow-up, and in one case, the avulsion was found at re-arthroscopy after 6 weeks to have healed.

Closed reduction of displaced or dislocated mandibular condyle fractures in children using threaded Kirschner wire and external rubber traction.

PubMed

Kim, J H; Nam, D H

2015-10-01

Most surgeons agree that closed treatment provides the best results for condylar fractures in children. Nevertheless, treatment of the paediatric mandibular condyle fracture that is severely displaced or dislocated is controversial. The purpose of this study was to investigate the long-term clinical and radiological outcomes following the treatment of displaced or dislocated condylar fractures in children using threaded Kirschner wire and external rubber traction. This procedure can strengthen the advantage of closed reduction and make up for the shortcomings of open reduction. From March 1, 2005 to December 25, 2011, 11 children aged between 4 and 12 years with displaced or dislocated mandibular condyle fractures were treated using threaded Kirschner wire and external rubber traction under portable C-arm fluoroscopy. All patients had unilateral displaced or dislocated condylar fractures. The follow-up period ranged from 24 to 42 months (mean 29.3 months). Normal occlusion and pain-free function of the temporomandibular joint, without deviation or limitation of jaw opening, was achieved in all patients. This closed reduction technique in displaced or dislocated condylar fractures in children offers a reliable solution in preventing the unfavourable sequelae of closed treatment and the open technique, such as altered morphology, functional disturbances, and facial nerve damage. Copyright © 2015 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Diaphragm-Sparing Nerve Blocks for Shoulder Surgery.

PubMed

Tran, De Q H; Elgueta, Maria Francisca; Aliste, Julian; Finlayson, Roderick J

Shoulder surgery can result in significant postoperative pain. Interscalene brachial plexus blocks (ISBs) constitute the current criterion standard for analgesia but may be contraindicated in patients with pulmonary pathology due to the inherent risk of phrenic nerve block and symptomatic hemidiaphragmatic paralysis. Although ultrasound-guided ISB with small volumes (5 mL), dilute local anesthetic (LA) concentrations, and LA injection 4 mm lateral to the brachial plexus have been shown to reduce the risk of phrenic nerve block, no single intervention can decrease its incidence below 20%. Ultrasound-guided supraclavicular blocks with LA injection posterolateral to the brachial plexus may anesthetize the shoulder without incidental diaphragmatic dysfunction, but further confirmatory trials are required. Ultrasound-guided C7 root blocks also seem to offer an attractive, diaphragm-sparing alternative to ISB. However, additional large-scale studies are needed to confirm their efficacy and to quantify the risk of periforaminal vascular breach. Combined axillary-suprascapular nerve blocks may provide adequate postoperative analgesia for minor shoulder surgery but do not compare favorably to ISB for major surgical procedures. One intriguing solution lies in the combined use of infraclavicular brachial plexus blocks and suprascapular nerve blocks. Theoretically, the infraclavicular approach targets the posterior and lateral cords, thus anesthetizing the axillary nerve (which supplies the anterior and posterior shoulder joint), as well as the subscapular and lateral pectoral nerves (both of which supply the anterior shoulder joint), whereas the suprascapular nerve block anesthetizes the posterior shoulder. Future randomized trials are required to validate the efficacy of combined infraclavicular-suprascapular blocks for shoulder surgery.

Peptidergic innervation of the human male genital tract.

PubMed

Gu, J; Polak, J M; Probert, L; Islam, K N; Marangos, P J; Mina, S; Adrian, T E; McGregor, G P; O'Shaughnessy, D J; Bloom, S R

1983-08-01

Four peptides--vasoactive intestinal polypeptide, substance P, somatostatin and a peptide-like avian pancreatic polypeptide--have been found in nerves of the human male genitalia using highly sensitive and specific methods of immunocytochemistry and radioimmunoassay. Five other peptides (met-enkephalin, leu-enkephalin, neurotensin, bombesin and cholecystokinin-8) were absent. Vasoactive intestinal polypeptide was the most abundant peptide, its highest concentration being in the proximal corpus cavernosum. Immunoelectron microscopy localized this peptide to large (97 +/- 20 nm), round, electron-dense granules of p-type nerve terminals. Vasoactive intestinal polypeptide-immunoreactive neuronal cell bodies were found in the prostate gland and the root of the corpus cavernosum. Substance P immunoreactive material was present in smaller concentration and was mainly localized in nerves around the corpuscular receptors of the glans penis. Somatostatin immunoreactive nerves were associated mainly with the smooth muscle of the seminal vesicle and the vas deferens. When antiserum to avian pancreatic polypeptide was applied, certain nerves were stained, particularly in the vas deferens, the prostate gland and the seminal vesicle. However, chromatography detected no pure avian pancreatic polypeptide suggesting the presence of a structurally related substance, possibly neuropeptide Y, which cross-reacts with the avian pancreatic polypeptide antiserum. Similar distributions between vasoactive intestinal polypeptide-immunoreactive and acetylcholinesterase-positive nerves and between avian pancreatic polypeptide-immunoreactive and adrenergic nerves were observed. A general neuronal marker, neuron-specific enolase, was used to investigate the general pattern of the organ's innervation. The abundance and distribution patterns of these peptide-immunoreactive nerves indicate that they may play important roles in the male sexual physiology.

Retropharyngeal Contralateral C7 Nerve Transfer to the Lower Trunk for Brachial Plexus Birth Injury: Technique and Results.

PubMed

Vu, Anthony T; Sparkman, Darlene M; van Belle, Christopher J; Yakuboff, Kevin P; Schwentker, Ann R

2018-05-01

Brachial plexus birth injuries with multiple nerve root avulsions present a particularly difficult reconstructive challenge because of the limited availability of donor nerves. The contralateral C7 has been described for brachial plexus reconstruction in adults but has not been well-studied in the pediatric population. We present our technique and results for retropharyngeal contralateral C7 nerve transfer to the lower trunk for brachial plexus birth injury. We performed a retrospective review. Any child aged less than 2 years was included. Charts were analyzed for patient demographic data, operative variables, functional outcomes, complications, and length of follow-up. We had a total of 5 patients. Average nerve graft length was 3 cm. All patients had return of hand sensation to the ulnar nerve distribution as evidenced by a pinch test, unprompted use of the recipient limb without mirror movement, and an Active Movement Scale (AMS) of at least 2/7 for finger and thumb flexion; one patient had an AMS of 7/7 for finger and thumb flexion. Only one patient had return of ulnar intrinsic hand function with an AMS of 3/7. Two patients had temporary triceps weakness in the donor limb and one had clinically insignificant temporary phrenic nerve paresis. No complications were related to the retropharyngeal nerve dissection in any patient. Average follow-up was 3.3 years. The retropharyngeal contralateral C7 nerve transfer is a safe way to supply extra axons to the severely injured arm in brachial plexus birth injuries with no permanent donor limb deficits. Early functional recovery in these patients, with regard to hand function and sensation, is promising. Therapeutic V. Copyright © 2018 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

The distribution of nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) in the medulla oblongata, spinal cord, cranial and spinal nerves of frog, Microhyla ornata.

PubMed

Jadhao, Arun G; Biswas, Saikat P; Bhoyar, Rahul C; Pinelli, Claudia

2017-04-01

Nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) enzymatic activity has been reported in few amphibian species. In this study, we report its unusual localization in the medulla oblongata, spinal cord, cranial nerves, spinal nerves, and ganglions of the frog, Microhyla ornata. In the rhombencephalon, at the level of facial and vagus nerves, the NADPH-d labeling was noted in the nucleus of the abducent and facial nerves, dorsal nucleus of the vestibulocochlear nerve, the nucleus of hypoglossus nerve, dorsal and lateral column nucleus, the nucleus of the solitary tract, the dorsal field of spinal grey, the lateral and medial motor fields of spinal grey and radix ventralis and dorsalis (2-10). Many ependymal cells around the lining of the fourth ventricle, both facial and vagus nerves and dorsal root ganglion, were intensely labeled with NADPH-d. Most strikingly the NADPH-d activity was seen in small and large sized motoneurons in both medial and lateral motor neuron columns on the right and left sides of the brain. This is the largest stained group observed from the caudal rhombencephalon up to the level of radix dorsalis 10 in the spinal cord. The neurons were either oval or elongated in shape with long processes and showed significant variation in the nuclear and cellular diameter. A massive NADPH-d activity in the medulla oblongata, spinal cord, and spinal nerves implied an important role of this enzyme in the neuronal signaling as well as in the modulation of motor functions in the peripheral nervous systems of the amphibians. Copyright © 2017 Elsevier B.V. All rights reserved.

Transplantation of Human Dental Pulp-Derived Stem Cells or Differentiated Neuronal Cells from Human Dental Pulp-Derived Stem Cells Identically Enhances Regeneration of the Injured Peripheral Nerve.

PubMed

Ullah, Imran; Park, Ju-Mi; Kang, Young-Hoon; Byun, June-Ho; Kim, Dae-Geon; Kim, Joo-Heon; Kang, Dong-Ho; Rho, Gyu-Jin; Park, Bong-Wook

2017-09-01

Human dental mesenchymal stem cells isolated from the dental follicle, pulp, and root apical papilla of extracted wisdom teeth have been known to exhibit successful and potent neurogenic differentiation capacity. In particular, human dental pulp-derived stem cells (hDPSCs) stand out as the most prominent source for in vitro neuronal differentiation. In this study, to evaluate the in vivo peripheral nerve regeneration potential of hDPSCs and differentiated neuronal cells from DPSCs (DF-DPSCs), a total of 1 × 10 6 hDPSCs or DF-hDPSCs labeled with PKH26 tracking dye and supplemented with fibrin glue scaffold and collagen tubulization were transplanted into the sciatic nerve resection (5-mm gap) of rat models. At 12 weeks after cell transplantation, both hDPSC and DF-hDPSC groups showed notably increased behavioral activities and higher muscle contraction forces compared with those in the non-cell transplanted control group. In immunohistochemical analysis of regenerated nerve specimens, specific markers for angiogenesis, axonal fiber, and myelin sheath increased in both the cell transplantation groups. Pretransplanted labeled PKH26 were also distinctly detected in the regenerated nerve tissues, indicating that transplanted cells were well-preserved and differentiated into nerve cells. Furthermore, no difference was observed in the nerve regeneration potential between the hDPSC and DF-hDPSC transplanted groups. These results demonstrate that dental pulp tissue is an excellent stem cell source for nerve regeneration, and in vivo transplantation of the undifferentiated hDPSCs could exhibit sufficient and excellent peripheral nerve regeneration potential.

Axonal morphological changes following impulse activity in mouse peripheral nerve in vivo: the return pathway for sodium ions.

PubMed

Trigo, Diogo; Smith, Kenneth J

2015-02-15

Conduction in myelinated axons involves substantial ion movements that must be reversed to restore homeostasis. The pathway taken by sodium ions returning to their original location and the potential osmotic consequences are currently unknown. We report striking morphological changes in axons following sustained impulse conduction that appear to result from osmosis and to indicate accumulation of ions in the periaxonal space followed by their release at the paranode. We conclude that the morphological changes illustrate a hitherto unrecognized part of normal axonal physiology that may also indicate the return pathway for the sodium ions involved in impulse formation. Myelinated axons can conduct sustained trains of impulses at high frequency, but this involves substantial ion movements that must be reversed to restore homeostasis. Little attention has been paid to the potential osmotic consequences of the ion movements or to the pathway taken by sodium ions returning to their original endoneurial location, given that the axolemmal Na(+)-K(+)-ATPase extrudes these ions into the periaxonal space beneath the myelin rather than into the endoneurium. Serial confocal imaging of fluorescent axons conducting at sustained physiological frequencies in vivo has revealed surprising morphological changes that may illuminate these problems. Saphenous nerves and spinal roots of anaesthetized transgenic mice expressing axoplasmic yellow fluorescent protein were stimulated electrically or pharmacologically (veratridine). Within 2 h, the axon herniated on one or both sides of the nodal membrane, displacing the paranodal myelin and widening the nodal gap. The herniated axoplasm became directed back towards the internode, forming a 'cap' up to 30 μm long. Concurrently, the fluid in the expanded periaxonal space accumulated into droplets that appeared to travel to the paranode, where they escaped. No such alterations occurred in axons treated with sodium channel or Na(+)-K(+)-ATPase inhibitors. Remarkably, impulse conduction continued throughout, and all these changes reversed spontaneously over hours or days. The morphological changes were verified ultrastructurally, and occurred in virtually all myelinated axons. The findings appear to reveal an overlooked part of the physiological repertoire of nerve fibres, and here they are interpreted in terms of osmotic changes that may illuminate the pathway by which sodium ions return to the endoneurial space after they have entered the axon during impulse conduction. © 2014 The Authors. The Journal of Physiology © 2014 The Physiological Society.

Dilation of the oropharynx via selective stimulation of the hypoglossal nerve

NASA Astrophysics Data System (ADS)

Huang, Jingtao; Sahin, Mesut; Durand, Dominique M.

2005-12-01

The functional effects of selective hypoglossal nerve (HG) stimulation with a multi-contact peripheral nerve electrode were assessed using images of the upper airways and the tongue in anesthetized beagles. A biphasic pulse train of 50 Hz frequency and 2 s duration was applied through each one of the tripolar contact sets of the nerve electrode while the pharyngeal images were acquired into a computer. The stimulation current was limited to 20% above the activation threshold for maximum selectivity. The images showed that various contact sets could generate several different activation patterns of the tongue muscles resulting in medial and/or lateral dilation and closing of the airways at the tongue root. Some of these patterns translated into an increase in the oropharyngeal size while others did not have any effect. The pharyngeal sizes were not statistically different during stimulation either between the two different positions of the head (30° and 60°), or when the lateral contacts were compared with the medial ones. The contacts that had the least effect generated an average of 53 ± 15% pharyngeal dilation relative to the best contacts, indicating that the results are marginally sensitive to the contact position around the HG nerve trunk. These results suggest that selective HG nerve stimulation can be a useful technique to produce multiple tongue activation patterns that can dilate the pharynx. This may in turn increase the size of the patient population who can benefit from HG nerve stimulation as a treatment method for obstructive sleep apnea.

Child neurology: Brachial plexus birth injury: what every neurologist needs to know.

PubMed

Pham, Christina B; Kratz, Johannes R; Jelin, Angie C; Gelfand, Amy A

2011-08-16

While most often transient, brachial plexus birth injury can cause permanent neurologic injury. The major risk factors for brachial plexus birth injury are fetal macrosomia and shoulder dystocia. The degree of injury to the brachial plexus should be determined in the neonatal nursery, as those infants with the most severe injury--root avulsion--should be referred early for surgical evaluation so that microsurgical repair of the plexus can occur by 3 months of life. Microsurgical repair options include nerve grafts and nerve transfers. All children with brachial plexus birth injury require ongoing physical and occupational therapy and close follow-up to monitor progress.

Trigeminal neuralgia caused by an anomalous posterior inferior cerebellar artery from the primitive trigeminal artery: case report.

PubMed

Lee, Seung Hwan; Koh, Jun Seok; Lee, Cheol Young

2011-06-01

A 61-year-old woman presented with typical trigeminal neuralgia (TN), caused by an aberrant posterior inferior cerebellar artery (PICA) associated with the primitive trigeminal artery (PTA). Magnetic resonance angiography and digital subtraction angiography clearly showed an anomalous artery directly originating from the PTA and coursing into the PICA territory at the cerebellum. During microvascular decompression (MVD), we confirmed and decompressed vascular compression of the trigeminal nerve by this anomalous, PICA-variant type of PTA. The PTA did not conflict with the trigeminal nerve, and the anomalous PICA only compressed the caudolateral part of the trigeminal nerve, without the more common compression at its root entry zone. This case is informative due not only to its very unusual angioanatomical variation but also to its helpfulness for surgeons preparing a MVD for a TN associated with such a rare vascular anomaly.

Cholinergic, serotoninergic and peptidergic components of the nervous system of Discocotyle sagittata (Monogenea:Polyopisthocotylea).

PubMed

Cable, J; Marks, N J; Halton, D W; Shaw, C; Johnston, C F; Tinsley, R C; Gannicott, A M

1996-12-01

Cholinergic, serotoninergic (5-HT) and peptidergic neuronal pathways have been demonstrated in both central and peripheral nervous systems of adult Discocotyle sagittata, using enzyme histochemistry and indirect immunocytochemistry in conjunction with confocal scanning laser microscopy. Antisera to 2 native flatworm neuropeptides, neuropeptide F and the FMRFamide-related peptide (FaRP), GNFFRFamide, were employed to detect peptide immunoreactivity. The CNS is composed of paired cerebral ganglia and connecting dorsal commissure, together with several paired longitudinal nerve cords. The main longitudinal nerve cords (lateral, ventral and dorsal) are interconnected at intervals by a series of annular cross-connectives, producing a ladder-like arrangement typical of the platyhelminth nervous system. At the level of the haptor, the ventral cords provide nerve roots which innervate each of the 9 clamps. Cholinergic and peptidergic neuronal organisation was similar, but distinct from that of the serotoninergic components. The PNS and reproductive system are predominantly innervated by peptidergic neurones.

Ophthalmic manifestations of maxillary sinus mucoceles.

PubMed

Ormerod, L D; Weber, A L; Rauch, S D; Feldon, S E

1987-08-01

Mucoceles involving any of the paranasal sinuses may present with ophthalmic disturbances. Maxillary antral mucoceles can encroach on the inferior orbit with ocular displacement and compression, proptosis or enophthalmos, lower lid distortion, tethering of extraocular muscles, and ptosis. Periocular pain, erosion of the inferior orbital rim, infraorbital nerve compression, epiphora, and inner canthal swellings are other important presentations. Postoperative mucoceles may involve only a portion of the antrum. Five illustrative cases are presented.

Posterior subscapular dissection: An improved approach to the brachial plexus for human anatomy students.

PubMed

Hager, Shaun; Backus, Timothy Charles; Futterman, Bennett; Solounias, Nikos; Mihlbachler, Matthew C

2014-05-01

Students of human anatomy are required to understand the brachial plexus, from the proximal roots extending from spinal nerves C5 through T1, to the distal-most branches that innervate the shoulder and upper limb. However, in human cadaver dissection labs, students are often instructed to dissect the brachial plexus using an antero-axillary approach that incompletely exposes the brachial plexus. This approach readily exposes the distal segments of the brachial plexus but exposure of proximal and posterior segments require extensive dissection of neck and shoulder structures. Therefore, the proximal and posterior segments of the brachial plexus, including the roots, trunks, divisions, posterior cord and proximally branching peripheral nerves often remain unobserved during study of the cadaveric shoulder and brachial plexus. Here we introduce a subscapular approach that exposes the entire brachial plexus, with minimal amount of dissection or destruction of surrounding structures. Lateral retraction of the scapula reveals the entire length of the brachial plexus in the subscapular space, exposing the brachial plexus roots and other proximal segments. Combining the subscapular approach with the traditional antero-axillary approach allows students to observe the cadaveric brachial plexus in its entirety. Exposure of the brachial dissection in the subscapular space requires little time and is easily incorporated into a preexisting anatomy lab curriculum without scheduling additional time for dissection. Copyright © 2014 Elsevier GmbH. All rights reserved.

Gasserian Ganglion and Retrobulbar Nerve Block in the Treatment of Ophthalmic Postherpetic Neuralgia: A Case Report.

PubMed

Huang, Jie; Ni, Zhongge; Finch, Philip

2017-09-01

Varicella zoster virus reactivation can cause permanent histological changes in the central and peripheral nervous system. Neural inflammatory changes or damage to the dorsal root ganglia sensory nerve fibers during reactivation can lead to postherpetic neuralgia (PHN). For PHN of the first division of the fifth cranial nerve (ophthalmic division of the trigeminal ganglion), there is evidence of inflammatory change in the ganglion and adjacent ocular neural structures. First division trigeminal nerve PHN can prove to be difficult and sometimes even impossible to manage despite the use of a wide range of conservative measures, including anticonvulsant and antidepressant medication. Steroids have been shown to play an important role by suppressing neural inflammatory processes. We therefore chose the trigeminal ganglion as an interventional target for an 88-year-old woman with severe ophthalmic division PHN after she failed to respond to conservative treatment. Under fluoroscopic guidance, a trigeminal ganglion nerve block was performed with lidocaine combined with dexamethasone. A retrobulbar block with lidocaine and triamcinolone settled residual oculodynia. At 1-year follow-up, the patient remained pain free and did not require analgesic medication. To our knowledge, this is the first reported case of ophthalmic division PHN successfully treated with a combination of trigeminal ganglion and retrobulbar nerve block using a local anesthetic agent and steroid for central and peripheral neural inflammatory processes. © 2016 World Institute of Pain.

Anatomical study of the superior cluneal nerves: application to low back pain and surgical approaches to the lumbar vertebrae.

PubMed

Iwanaga, Joe; Simonds, Emily; Patel, Mayank; Oskouian, Rod J; Tubbs, R Shane

2018-05-19

The aim of this study was to investigate the anatomy of the superior cluneal nerves more proximal to the posterior layer of the thoracolumbar fascia. Twelve sides of six fresh-frozen cadavers were used. The age at death ranged from 54 to 88 years. After a transverse skin incision 10 mm above the iliac crest, the superior cluneal nerves were detected by blunt dissection and traced back to the dorsal root ganglia. The diameter of the nerves from L1 to L3 was measured. Also, the relationship to the erector spinae muscle and dorsal ramus was recorded. The mean diameters of the origin of the L1, L2 and L3 were 1.71±0.29 mm, 1.73±0.40 mm and 1.52±0.55 mm, respectively. On seven sides (58.3%) for L1, seven sides (58.3%) for L2, and ten sides (83.3%) for L3, the nerves pierced the iliocostalis muscle. One side (8.3%) for L2 and one (8.3%) for L3 had no cutaneous branch. The results of this study could help to elucidate the anatomy of the superior cluneal nerves and help avoid complications during surgical approaches to the lumbar spine. Copyright © 2018. Published by Elsevier Inc.

Sodium-dependent Vitamin C transporter 2 deficiency impairs myelination and remyelination after injury: Roles of collagen and demethylation.

PubMed

Röhr, Dominik; Halfter, Hartmut; Schulz, Jörg B; Young, Peter; Gess, Burkhard

2017-07-01

Peripheral nerve myelination involves rapid production of tightly bound lipid layers requiring cholesterol biosynthesis and myelin protein expression, but also a collagen-containing extracellular matrix providing mechanical stability. In previous studies, we showed a function of ascorbic acid in peripheral nerve myelination and extracellular matrix formation in adult mice. Here, we sought the mechanism of action of ascorbic acid in peripheral nerve myelination using different paradigms of myelination in vivo and in vitro. We found impaired myelination and reduced collagen expression in Sodium-dependent Vitamin C Transporter 2 heterozygous mice (SVCT2 +/- ) during peripheral nerve development and after peripheral nerve injury. In dorsal root ganglion (DRG) explant cultures, hypo-myelination could be rescued by precoating with different collagen types. The activity of the ascorbic acid-dependent demethylating Ten-eleven-translocation (Tet) enzymes was reduced in ascorbic acid deprived and SVCT2 +/- DRG cultures. Further, in ascorbic acid-deprived DRG cultures, methylation of a CpG island in the collagen alpha1 (IV) and alpha2 (IV) bidirectional promoter region was increased compared to wild-type and ascorbic acid treated controls. Taken together, these results provide further evidence for the function of ascorbic acid in myelination and extracellular matrix formation in peripheral nerves and suggest a putative molecular mechanism of ascorbic acid function in Tet-dependent demethylation of collagen promoters. © 2017 Wiley Periodicals, Inc.

17β-Estradiol Promotes Schwann Cell Proliferation and Differentiation, Accelerating Early Remyelination in a Mouse Peripheral Nerve Injury Model

PubMed Central

Chen, Yan; Guo, Wenjie; Li, Wenjuan; Cheng, Meng; Hu, Ying; Xu, Wenming

2016-01-01

Estrogen induces oligodendrocyte remyelination in response to demyelination in the central nervous system. Our objective was to determine the effects of 17β-estradiol (E2) on Schwann cell function and peripheral nerve remyelination after injury. Adult male C57BL/6J mice were used to prepare the sciatic nerve transection injury model and were randomly categorized into control and E2 groups. To study myelination in vitro, dorsal root ganglion (DRG) explant culture was prepared using 13.5-day-old mouse embryos. Primary Schwann cells were isolated from the sciatic nerves of 1- to 3-day-old Sprague–Dawley rats. Immunostaining for myelin basic protein (MBP) expression and toluidine blue staining for myelin sheaths demonstrated that E2 treatment accelerates early remyelination in the “nerve bridge” region between the proximal and distal stumps of the transection injury site in the mouse sciatic nerve. The 5-bromo-2′-deoxyuridine incorporation assay revealed that E2 promotes Schwann cell proliferation in the bridge region and in the primary culture, which is blocked using AKT inhibitor MK2206. The in vitro myelination in the DRG explant culture determined showed that the MBP expression in the E2-treated group is higher than that in the control group. These results show that E2 promotes Schwann cell proliferation and myelination depending on AKT activation. PMID:27872858

Peripheral axotomy of the rat mandibular trigeminal nerve leads to an increase in VIP and decrease of other primary afferent neuropeptides in the spinal trigeminal nucleus.

PubMed

Atkinson, M E; Shehab, S A

1986-12-01

In the vasoactive intestinal polypeptide (VIP)-rich lumbosacral spinal cord, VIP increases at the expense of other neuropeptides after primary sensory nerve axotomy. This study was undertaken to ascertain whether similar changes occur in peripherally axotomised cranial sensory nerves. VIP immunoreactivity increased in the terminal region of the mandibular nerve in the trigeminal nucleus caudalis following unilateral section of the sensory root of the mandibular trigeminal nerve at the foramen orale. Other primary afferent neuropeptides (substance P, cholecystokinin and somatostatin) were depleted and fluoride-resistant acid phosphatase activity was abolished in the same circumscribed areas of the nucleus caudalis. The rise in VIP and depletion of other markers began 4 days postoperatively and was maximal by 10 days, these levels remaining unchanged up to 1 year postoperatively. VIP-immunoreactive cell bodies were absent from trigeminal ganglia from the unoperated side but small and medium cells stained intensely in the ganglia of the operated side after axotomy. These observations indicate that increase of VIP in sensory nerve terminals is a general phenomenon occurring in both cranial and spinal sensory terminal areas. The intense VIP immunoreactivity in axotomised trigeminal ganglia suggests that the increased levels of VIP in the nucleus caudalis are of peripheral origin, indicating a change in expression of neuropeptides within primary afferent neurons following peripheral axotomy.

Period Prevalence of Acute Neck Injury in US Air Force Pilots Exposed to High G Forces

DTIC Science & Technology

1986-06-01

entities caused by irritation or compression of the cervical nerve roots. Several types of syndromes are recognized: Cervical neck muscle pain or...Spondylolysis 5. Spondylolisthesis 6. Scheuermann’s Disease ( Kyphosis ) 7. Prominent Lordosis or Kyphosis 8. Klippel-Feil Anomaly (Congenital Short Neck) 9

Extraforaminal Discal Cyst as Cause of Radiculopathy.

PubMed

Mathon, Bertrand; Bienvenot, Peggy; Leclercq, Delphine

2018-01-01

We report the first extraforaminal location of a lumbar discal cyst. The patient was treated by hemilaminectomy, arthrectomy, cyst resection, and unilateral arthrodesis, achieving complete release of the nerve root. Extraforaminal lumbar discal cyst may represent an unexpected cause of sciatic pain with favorable outcome after surgical resection. Copyright © 2017 Elsevier Inc. All rights reserved.

Accidental injury of the inferior alveolar nerve due to the extrusion of calcium hydroxide in endodontic treatment: a case report

PubMed Central

2016-01-01

During clinical endodontic treatment, we often find radiopaque filling material beyond the root apex. Accidental extrusion of calcium hydroxide could cause the injury of inferior alveolar nerve, such as paresthesia or continuous inflammatory response. This case report presents the extrusion of calcium hydroxide and treatment procedures including surgical intervention. A 48 yr old female patient experienced Calcipex II extrusion in to the inferior alveolar canal on left mandibular area during endodontic treatment. After completion of endodontic treatment on left mandibular first molar, surgical intervention was planned under general anesthesia. After cortical bone osteotomy and debridement, neuroma resection and neurorrhaphy was performed, and prognosis was observed. But no improvement in sensory nerve was seen following surgical intervention after 20 mon. A clinician should be aware of extrusion of intracanal medicaments and the possibility of damage on inferior alveolar canal. Injectable type of calcium hydroxide should be applied with care for preventing nerve injury. The alternative delivery method such as lentulo spiral was suggested on the posterior mandibular molar. PMID:26877992

Conduction studies of the normal sural nerve.

PubMed

Horowitz, S H; Krarup, C

1992-03-01

The sural nerve was studied orthodromically using the near-nerve technique in 273 normal subjects (155 females, 118 males) aged 5 to 90 years. The sensory action potential (SAP), evoked at the dorsum of the foot, was recorded at the lateral malleolus and midcalf, and at the midcalf when evoked at the lateral malleolus. In addition, the SAP was recorded at intermediate distal sites and at proximal sites at the popliteal fossa, the gluteal fold, and the S-1 root. The amplitude of the SAP recorded at midcalf was 32% higher in females than in males. This was probably due to volume-conduction properties, as differences between genders were less noticeable at more distal recording sites. The amplitude decreased steeply and exponentially with age. Conduction distance had a strong influence on the amplitude of the SAP, which decreased with increasing distance following a power relationship with an exponent of 1.4 to 1.7. This decrease was due to temporal dispersion with decreased summation and increased phase cancellation. The conduction velocity was slightly lower along the very distal course of the nerve than along more proximal segments.

Wet cupping therapy improves local blood perfusion and analgesic effects in patients with nerve-root type cervical spondylosis.

PubMed

Meng, Xiang-Wen; Wang, Ying; Piao, Sheng-Ai; Lv, Wen-Tao; Zhu, Cheng-Hui; Mu, Ming-Yuan; Li, Dan-Dan; Liu, Hua-Peng; Guo, Yi

2018-01-15

To observe wet cupping therapy (WCT) on local blood perfusion and analgesic effects in patients with nerve-root type cervical spondylosis (NT-CS). Fifty-seven NT-CS patients were randomly divided into WCT group and Jiaji acupoint-acupuncture (JA) group according a random number table. WCT group (30 cases) was treated with WCT for 10 min, and JA group (27 cases) was treated with acupuncture for 10 min. The treatment effificacies were evaluated with a Visual Analogue Scale (VAS). Blood perfusion at Dazhui (GV 14) and Jianjing (GB 21) acupoints (affected side) was observed with a laser speckle flflowmetry, and its variations before and after treatment in both groups were compared as well. In both groups, the VAS scores signifificantly decreased after the intervention (P<0.01), while the blood perfusion at the two acupoints signifificantly increased after intervention (P<0.05); however, the increasement magnitude caused by WCT was obvious compared with JA (P<0.05). WCT could improve analgesic effects in patients with NT-CS, which might be related to increasing local blood perfusion of acupunct points.

Painful Lumbosacral Plexopathy

PubMed Central

Ehler, Edvard; Vyšata, Oldřich; Včelák, Radek; Pazdera, Ladislav

2015-01-01

Abstract Patients frequently suffer from lumbosacral plexus disorder. When conducting a neurological examination, it is essential to assess the extent of muscle paresis, sensory disorder distribution, pain occurrence, and blocked spine. An electromyography (EMG) can confirm axonal lesions and their severity and extent, root affliction (including dorsal branches), and disorders of motor and sensory fiber conduction. Imaging examination, particularly gadolinium magnetic resonance imaging (MRI) examination, ensues. Cerebrospinal fluid examination is of diagnostic importance with radiculopathy, neuroinfections, and for evidence of immunoglobulin synthesis. Differential diagnostics of lumbosacral plexopathy (LSP) include metabolic, oncological, inflammatory, ischemic, and autoimmune disorders. In the presented case study, a 64-year-old man developed an acute onset of painful LSP with a specific EMG finding, MRI showing evidence of plexus affliction but not in the proximal part of the roots. Painful plexopathy presented itself with severe muscle paresis in the femoral nerve and the obturator nerve innervation areas, and gradual remission occurred after 3 months. Autoimmune origin of painful LSP is presumed. We describe a rare case of patient with painful lumbar plexopathy, with EMG findings of axonal type, we suppose of autoimmune etiology. PMID:25929915

Biophotons as neural communication signals demonstrated by in situ biophoton autography.

PubMed

Sun, Yan; Wang, Chao; Dai, Jiapei

2010-03-01

Cell to cell communication by biophotons has been demonstrated in plants, bacteria, animal neutrophil granulocytes and kidney cells. Whether such signal communication exists in neural cells is unclear. By developing a new biophoton detection method, called in situ biophoton autography (IBA), we have investigated biophotonic activities in rat spinal nerve roots in vitro. We found that different spectral light stimulation (infrared, red, yellow, blue, green and white) at one end of the spinal sensory or motor nerve roots resulted in a significant increase in the biophotonic activity at the other end. Such effects could be significantly inhibited by procaine (a regional anaesthetic for neural conduction block) or classic metabolic inhibitors, suggesting that light stimulation can generate biophotons that conduct along the neural fibers, probably as neural communication signals. The mechanism of biophotonic conduction along neural fibers may be mediated by protein-protein biophotonic interactions. This study may provide a better understanding of the fundamental mechanisms of neural communication, the functions of the nervous system, such as vision, learning and memory, as well as the mechanisms of human neurological diseases.

Roots Air Management System with Integrated Expander

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stretch, Dale; Wright, Brad; Fortini, Matt

2016-07-06

PEM fuel cells remain an emerging technology in the vehicle market with several cost and reliability challenges that must be overcome in order to increase market penetration and acceptance. The DOE has identified the lack of a cost effective, reliable, and efficient air supply system that meets the operational requirements of a pressurized PEM 80kW fuel cell as one of the major technological barriers that must be overcome. This project leveraged Roots positive displacement development advancements and demonstrated an efficient and low cost fuel cell air management system. Eaton built upon its P-Series Roots positive displacement design and shifted themore » peak efficiency making it ideal for use on an 80kW PEM stack. Advantages to this solution include: • Lower speed of the Roots device eliminates complex air bearings present on other systems. • Broad efficiency map of Roots based systems provides an overall higher drive cycle fuel economy. • Core Roots technology has been developed and validated for other transportation applications. Eaton modified their novel R340 Twin Vortices Series (TVS) Roots-type supercharger for this application. The TVS delivers more power and better fuel economy in a smaller package as compared to other supercharger technologies. By properly matching the helix angle with the rotor’s physical aspect ratio, the supercharger’s peak efficiency can be moved to the operating range where it is most beneficial for the application. The compressor was designed to meet the 90 g/s flow at a pressure ratio of 2.5, similar in design to the P-Series 340. A net shape plastic expander housing with integrated motor and compressor was developed to significantly reduce the cost of the system. This integrated design reduced part count by incorporating an overhung expander and motor rotors into the design such that only four bearings and two shafts were utilized.« less

An interdisciplinary tillage erosion experiment: establishing a new field in grassland with reconstructed ard plough of the Bronze Age - Iron Age

NASA Astrophysics Data System (ADS)

Pavelka, Jan; Smetanová, Anna; Rejman, Jerzy; Kováčik, Peter

2017-04-01

Despite recognising the role of tillage erosion in landforms evolution, little research has documented its effects in prehistoric times. Herein, an interdisciplinary archaeological-geomorphological experiment with reconstructed tillage tools and management was conducted in order to measure tillage erosion when a new field in grasslands was established in the Bronze Age-Iron Age. Three wooden ards were reconstructed based on archaeological findings. They were tested in a cross-tillage experiment, consisting of a tillage pass perpendicular to the primary slope (6.5-9.7%), and a second tillage pass parallel to the primary slope of a convex-convex ridge with mowed grass (0.2 m high, vegetation cover >90%). The standard sole ard proved to be the most effective, with a mean tillage depth of 0.12 m, a mean tillage speed of 3.8 km h-1, and a mean distance between furrows of 0.20-0.25 m. Only 13% of the 264 tracers placed on 6 transects were displaced, and the mean tracers displacement parallel to the primary slope was 0.04 ± 0.17 m. Contour tillage perpendicular to primary slope created V or U shaped furrows with a mean depth of 0.1-0.12 m, a mean width of 0.05-0.1 m, and incision under the main root zone. Only soil in direct contact with the ard was displaced, with a mean translocation distance of 0.06 ± 0.2 m parallel and 0.06 ± 0.3 m perpendicular to the primary slope. During tillage parallel to slope, soil clods of 0.20 x 0.25 x 0.10 m were created and slightly disturbed or turned over one another. The tracers moved within the furrows and with the soil clods. Loose soil, resembling a seedbed, was not covered by soil clods. Mean displacement during the second pass was 0.03 ± 0.19 m parallel and 0.00 ± 0.15 m perpendicular to primary slope. The displacement from cross-tillage with a wooden ard in permanent grasslands was lower than many previously measured values of traditional animal-powered metal ploughs in permanent fields. No relationship between mean soil displacement and slope gradient was found. Dense vegetation and root structure influenced ard soil-penetration, its movement within the soil, and the displacement of tracers packed between the roots. Cross-tillage with a wooden ard proved to be insufficient for seedbed preparation. The results suggest that grazing or fire management, followed by repeated tillage with ard or hoe in order to destroy soil clods were necessary to establish a new field in grasslands during the Bronze Age-Iron Age.

Protocol for Removal of Third Molar Root Tips from the Inferior Alveolar Canal-Crossing the line.

PubMed

Punga, Rohit; Keswani, Kiran

2014-12-01

The safe removal of third molars involved with the inferior alveolar canal (IAC) has been an area of concern since long. Many times we hesitate for the removal of third molars, fearing injury to the inferior alveolar nerve. The authors here describe a simple technique which can be used to remove third molars showing evidence of proximity to IAC on presurgical radiographic evaluation, as well as those root tips which, during removal, accidentally enter the IAC space. A step-by-step protocol is presented along with necessary precautions during the operative procedure.

[Iatrogenic risks during the obturation of the root canal system].

PubMed

Aesaert, G

2000-01-01

A hermetic seal is the main goal of obturation of the root canal system. For that purpose guttapercha still remains the filling material of choice. Most filling techniques use plasticized guttapercha and a condensation technique to fulfil the requirements of hermetic seal. The heat to plasticize and the forces applied to condense that material may have an influence on the periodontal ligament and/or the remaining tooth structure. Furthermore can overfilling of guttapercha and more likely the sealer, affect the periodontal tissue. Although rare, mandibular nerve damage and adverse effects on the sinus maxillaris can be the result of inadequate treatment.

Spatial separation of light perception and growth response in maize root phototropism.

PubMed

Mullen, J L; Wolverton, C; Ishikawa, H; Hangarter, R P; Evans, M L

2002-09-01

Although the effects of gravity on root growth are well known and interactions between light and gravity have been reported, details of root phototropic responses are less documented. We used high-resolution image analysis to study phototropism in primary roots of Zea mays L. Similar to the location of perception in gravitropism, the perception of light was localized in the root cap. Phototropic curvature away from the light, on the other hand, developed in the central elongation zone, more basal than the site of initiation of gravitropic curvature. The phototropic curvature saturated at approximately 10 micromoles m-2 s-1 blue light with a peak curvature of 29 +/- 4 degrees, in part due to induction of positive gravitropism following displacement of the root tip from vertical during negative phototropism. However, at higher fluence rates, development of phototropic curvature is arrested even if gravitropism is avoided by maintaining the root cap vertically using a rotating feedback system. Thus continuous illumination can cause adaptation in the signalling pathway of the phototropic response in roots.

Spatial separation of light perception and growth response in maize root phototropism

NASA Technical Reports Server (NTRS)

Mullen, J. L.; Wolverton, C.; Ishikawa, H.; Hangarter, R. P.; Evans, M. L.

2002-01-01

Although the effects of gravity on root growth are well known and interactions between light and gravity have been reported, details of root phototropic responses are less documented. We used high-resolution image analysis to study phototropism in primary roots of Zea mays L. Similar to the location of perception in gravitropism, the perception of light was localized in the root cap. Phototropic curvature away from the light, on the other hand, developed in the central elongation zone, more basal than the site of initiation of gravitropic curvature. The phototropic curvature saturated at approximately 10 micromoles m-2 s-1 blue light with a peak curvature of 29 +/- 4 degrees, in part due to induction of positive gravitropism following displacement of the root tip from vertical during negative phototropism. However, at higher fluence rates, development of phototropic curvature is arrested even if gravitropism is avoided by maintaining the root cap vertically using a rotating feedback system. Thus continuous illumination can cause adaptation in the signalling pathway of the phototropic response in roots.

Adaptive optics scanning laser ophthalmoscope using liquid crystal on silicon spatial light modulator: Performance study with involuntary eye movement

NASA Astrophysics Data System (ADS)

Huang, Hongxin; Toyoda, Haruyoshi; Inoue, Takashi

2017-09-01

The performance of an adaptive optics scanning laser ophthalmoscope (AO-SLO) using a liquid crystal on silicon spatial light modulator and Shack-Hartmann wavefront sensor was investigated. The system achieved high-resolution and high-contrast images of human retinas by dynamic compensation for the aberrations in the eyes. Retinal structures such as photoreceptor cells, blood vessels, and nerve fiber bundles, as well as blood flow, could be observed in vivo. We also investigated involuntary eye movements and ascertained microsaccades and drifts using both the retinal images and the aberrations recorded simultaneously. Furthermore, we measured the interframe displacement of retinal images and found that during eye drift, the displacement has a linear relationship with the residual low-order aberration. The estimated duration and cumulative displacement of the drift were within the ranges estimated by a video tracking technique. The AO-SLO would not only be used for the early detection of eye diseases, but would also offer a new approach for involuntary eye movement research.

Anomalous Impact in Reaction-Diffusion Financial Models

NASA Astrophysics Data System (ADS)

Mastromatteo, I.; Tóth, B.; Bouchaud, J.-P.

2014-12-01

We generalize the reaction-diffusion model A +B → /0 in order to study the impact of an excess of A (or B ) at the reaction front. We provide an exact solution of the model, which shows that the linear response breaks down: the average displacement of the reaction front grows as the square root of the imbalance. We argue that this model provides a highly simplified but generic framework to understand the square-root impact of large orders in financial markets.

Analysis of the spinal nerve roots in relation to the adjacent vertebral bodies with respect to a posterolateral vertebral body replacement procedure.

PubMed

Awwad, Waleed; Bourget-Murray, Jonathan; Zeiadin, Nadil; Mejia, Juan P; Steffen, Thomas; Algarni, Abdulrahman D; Alsaleh, Khalid; Ouellet, Jean; Weber, Michael; Jarzem, Peter F

2017-01-01

This study aims to improve the understanding of the anatomic variations along the thoracic and lumbar spine encountered during an all-posterior vertebrectomy, and reconstruction procedure. This information will help improve our understanding of human spine anatomy and will allow better planning for a vertebral body replacement (VBR) through either a transpedicular or costotransversectomy approach. The major challenge to a total posterior approach vertebrectomy and VBR in the thoracolumbar spine lies in the preservation of important neural structures. This was a retrospective analysis. Hundred normal magnetic resonance imaging (MRI) spinal studies (T1-L5) on sagittal T2-weighted MRI images were studied to quantify: (1) mid-sagittal vertebral body (VB) dimensions (anterior, midline, and posterior VB height), (2) midline VB and associated intervertebral discs height, (3) mean distance between adjacent spinal nerve roots (DNN) and mean distance between the inferior endplate of the superior vertebrae to its respective spinal nerve root (DNE), and (4) posterior approach expansion ratio (PAER). (1) The mean anterior VB height gradually increased craniocaudally from T1 to L5. The mean midline and posterior VB height showed a similar pattern up to L2. Mean posterior VB height was larger than the mean anterior VB height from T1 to L2, consistent with anterior wedging, and then measured less than the mean anterior VB height, indicating posterior wedging. (2) Midline VB and intervertebral disc height gradually increased from T1 to L4. (3) DNN and DNE were similar, whereby they gradually increased from T1 to L3. (5) Mean PAER varied between 1.69 (T12) and 2.27 (L5) depending on anatomic level. The dimensions of the thoracic and lumbar vertebrae and discs vary greatly. Thus, any attempt at carrying out a VBR from a posterior approach should take into account the specifications at each spinal level.

Refinement of myotome values in the upper limb: Evidence from brachial plexus injuries.

PubMed

Bell, S W; Brown, M J C; Hems, T J

2017-02-01

We reviewed patients with partial supraclavicular brachial plexus injuries in order to refine the myotome values of the upper limb. Forty-two patients with defined partial injuries to the supraclavicular brachial plexus were reviewed from a prospective database. The injuries patterns covered C5, C5-6, C5-7, C5-8, C7-T1 and C8-T1 roots. Upper plexus injuries were classified on the basis of surgical exploration and intraoperative stimulation and lower plexus injuries from MRI. Flexor Carpi Radialis (FCR) was paralyzed in C5-7 injuries, in addition to paralysis of deltoid, supraspinatus, infraspinatus and biceps, when compared to C5-6 injuries. Complete paralysis of Flexor Digitorum Profundus (FDP) and Flexor Digitorum Superficialis (FDS) to all digits was identified in C7-T1 injuries. In C5-8 injuries weakness was noted in FDP of ulnar digits and intrinsics innervated by the ulnar nerve, while in C8-T1 injuries paralysis was noted in the FDP to the radial digits. All patients with C8-T1 injuries had paralysis of FDS and the thenar muscles. In upper plexus injuries paralysis of FCR indicated involvement of C7 root in addition to C5 and C6 roots. The results provide new detail of innervation of muscles acting on the hand. Flexor muscles and intrinsic muscles of the thumb and radial fingers (median nerve) have an important contribution from T1, while for those acting on the ulnar digits (ulnar nerve) the main contribution is from C8 with some input from C7. T1 also gives consistent innervation to extensor pollicis longus. A revised myotome chart for the upper limb is proposed. Copyright © 2015 Royal College of Surgeons of Edinburgh (Scottish charity number SC005317) and Royal College of Surgeons in Ireland. Published by Elsevier Ltd. All rights reserved.

Fluoroscopically guided infiltration of the cervical nerve root: an indirect approach through the ipsilateral facet joint.

PubMed

Kelekis, Alexios; Filippiadis, Dimitrios K; Velonakis, Georgios; Martin, Jean-Baptist; Oikonomopoulos, Nikolaos; Brountzos, Elias; Kelekis, Nikolaos

2014-01-01

Transforaminal infiltrations in the cervical spine are governed by a higher rate of vascular puncture than in the lumbar spine. The purpose of our study is to assess the safety and efficacy of percutaneous, fluoroscopically guided nerve root infiltrations in cases of cervical radiculopathy. An indirect postero-lateral approach was performed through the ipsilateral facet joint. During the last 2 years, 25 patients experiencing cervical radiculopathy underwent percutaneous, fluoroscopically guided nerve root infiltrations by means of an indirect postero-lateral approach through the ipsilateral facet joint. The intra-articular position of the needle (22-gauge spinal needle) was fluoroscopically verified after injection of a small amount of contrast medium which also verified dispersion of the contrast medium periradicularly and in the epidural space. Then a mixture of long-acting glucocorticosteroid diluted in normal saline (1.5/1 mL) was injected intra-articularly. A questionnaire with a Numeric Visual Scale (NVS) scale helped assess pain relief, life quality, and mobility improvement. A mean of 2.3 sessions was performed in the patients of our study. In the vast majority of our patients 19/25 (76%), the second infiltration was performed within 7-10 days of the first one. Comparing the pain scores prior (mean value 8.80 ± 1.080 NVS units) and after (mean value 1.84 ± 1.405 NVS units), there was a mean decrease of 6.96 ± 1.695 NVS units [median value 7 NVS units (P < 0.001) in terms of pain reduction, effect upon mobility, and life quality. There were no clinically significant complications noted in our study. Fluoroscopically guided transforaminal infiltrations through the ipsilateral facet joint seem to be a feasible, efficacious, and safe approach for the treatment of patients with cervical radiculopathy. This approach facilitates needle placement and minimizes risk of complications.

Application of Gelatin Sponge Impregnated with a Mixture of 3 Drugs to Intraoperative Nerve Root Block Combined with Robot-Assisted Minimally Invasive Transforaminal Lumbar Interbody Fusion Surgery in the Treatment of Adult Degenerative Scoliosis: A Clinical Observation Including 96 Patients.

PubMed

Du, Jin Peng; Fan, Yong; Liu, Ji Jun; Zhang, Jia Nan; Chang Liu, Shi; Hao, Dingjun

2017-12-01

Application of nerve root block is mainly for diagnosis with less application in intraoperative treatment. The aim of this study was to observe clinical and imaging outcomes of application of gelatin sponge impregnated with a mixture of 3 drugs to intraoperative nerve root block combined with robot-assisted minimally invasive transforaminal lumbar interbody fusion surgery in to treat adult degenerative lumbar scoliosis. From January 2012 to November 2014, 108 patients with adult degenerative lumbar scoliosis were treated with robot-assisted minimally invasive transforaminal lumbar interbody fusion surgery combined with intraoperative gelatin sponge impregnated with a mixture of 3 drugs. Visual analog scale and Oswestry Disability Index scores were used to evaluate postoperative improvement of back and leg pain, and clinical effects were assessed according to the 36-Item Short-Form Health Survey. Imaging was obtained preoperatively, 1 week and 3 months postoperatively, and at the last follow-up. Fusion status, complications, and other outcomes were assessed. Follow-up was complete for 96 patients. Visual analog scale scores of leg and back pain on postoperative days 1-7 were decreased compared with preoperatively. At 1 week postoperatively, 3 months postoperatively, and last follow-up, visual analog scale score, Oswestry Disability Index score, coronal Cobb angle, and coronal and sagittal deviated distance decreased significantly (P = 0.000) and lumbar lordosis angle increased (P = 0.000) compared with preoperatively. Improvement rate of Oswestry Disability Index was 81.8% ± 7.4. Fusion rate between vertebral bodies was 92.7%. Application of gelatin sponge impregnated with 3 drugs combined with robot-assisted minimally invasive transforaminal lumbar interbody fusion for treatment of adult degenerative lumbar scoliosis is safe and feasible with advantages of good short-term analgesia effect, minimal invasiveness, short length of stay, and good long-term clinical outcomes. Copyright © 2017 Elsevier Inc. All rights reserved.