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Sample records for rat median nerve

  1. Effect of bilateral median nerve excision on sciatic functional index in rat: an applicable animal model for autologous nerve grafting.

    PubMed

    Nabian, Mohammad Hosein; Nadji-Tehrani, Mehdi; Zanjani, Leila Oryadi; Kamrani, Reza Shahryar; Rahimi-Movaghar, Vafa; Firouzi, Masoumeh

    2011-01-01

    Autologous nerve graft is still the treatment of choice in peripheral nerve injury when end-to-end nerve repair is not possible. The sciatic nerve is the most widely used nerve in rat experimental studies. To assess the possibility of using the rat median nerve as a delayed animal autologous nerve graft model in nerve regeneration studies, the effect of median nerve excision on the sciatic functional index (SFI) was evaluated. Thirty rats were distributed into three equal groups: in the sciatic and median nerve excision (SMNE) group, 10 mm of the right sciatic nerve was excised and 5 mm of both median nerves were excised a week later; in the median nerve excision (MNE) group, 5 mm of both median nerves were excised (both sciatic nerves remained intact); in the control group, no intervention was performed. SFI was calculated before and after each intervention. There was no significant difference between mean SFI values calculated before and after median nerve excision in SMNE (-86.8 versus -88.4, P = 0.61) and MNE groups (-3.9 versus -3.3, P = 0.93). Therefore, it may be suggested that median nerve excision does not affect SFI measurements in intact and/or completely injured sciatic nerve, which may propose the median nerve as an autologous donor nerve graft model in rats. © Thieme Medical Publishers.

  2. Bioartificial reconstruction of peripheral nerves using the rat median nerve model.

    PubMed

    Sinis, Nektarios; Kraus, Armin; Drakotos, Dimitris; Doser, Michael; Schlosshauer, Burkhard; Müller, Hans-Werner; Skouras, Emmanouil; Bruck, Johannes C; Werdin, Frank

    2011-07-01

    Different bioartificial tubes were recommended for peripheral nerve reconstruction in the past. In order to replace autologous nerve grafts this materials are still under review in different animal studies. Most of them are dealing with the rodent peripheral nerves. One very popular animal model to study different materials is the rat median nerve model. With its easy excess, simple behavioral tests and reliable long term results it is attractive to many scientists in this field. This review gives an overview about the past, current and future options in this model for bioartificial nerve tubes. It summarizes the evolution of successful implantation of different materials across short nerve gaps and demonstrates the obstacles arising from long nerve gaps and the problems associated to them. Copyright © 2011 Elsevier GmbH. All rights reserved.

  3. Does Pulsed Magnetic Field Therapy Influence Nerve Regeneration in the Median Nerve Model of the Rat?

    PubMed Central

    Beck-Broichsitter, Benedicta E.; Lamia, Androniki; Fregnan, Federica; Smeets, Ralf; Becker, Stephan T.; Sinis, Nektarios

    2014-01-01

    The aim of this study was to evaluate the impact of pulsed magnetic field therapy on peripheral nerve regeneration after median nerve injury and primary coaptation in the rat. Both median nerves were surgically exposed and denervated in 24 female Wistar rats. A microsurgical coaptation was performed on the right side, whereas on the left side a spontaneous healing was prevented. The study group underwent a daily pulsed magnetic field therapy; the other group served as a control group. The grasping force was recorded 2 weeks after the surgical intervention for a period of 12 weeks. The right median nerve was excised and histologically examined. The histomorphometric data and the functional assessments were analyzed by t-test statistics and one-way ANOVA. One-way ANOVA indicated a statistically significant influence of group affiliation and grasping force (P = 0.0078). Grasping strength was higher on a significant level in the experimental group compared to the control group permanently from the 9th week to the end of the study. T-test statistics revealed a significantly higher weight of the flexor digitorum sublimis muscle (P = 0.0385) in the experimental group. The histological evaluation did not reveal any statistically significant differences concerning the histomorphometric parameters. Our results suggest that the pulsed magnetic field therapy has a positive influence on the functional aspects of neural regeneration. More studies are needed to precisely evaluate and optimize the intensity and duration of the application. PMID:25143937

  4. Distal median nerve dysfunction

    MedlinePlus

    ... Distal median nerve dysfunction is a form of peripheral neuropathy that affects the movement of or sensation in ... and the A.D.A.M. Editorial team. Peripheral Nerve Disorders Read more Latest Health News Read more Health ...

  5. The anabolic steroid nandrolone enhances motor and sensory functional recovery in rat median nerve repair with long interpositional nerve grafts.

    PubMed

    Ghizoni, Marcos Flávio; Bertelli, Jayme Augusto; Grala, Carolina Giesel; da Silva, Rosemeri Maurici

    2013-01-01

    Recovery from peripheral nerve repair is frequently incomplete. Hence drugs that enhance nerve regeneration are needed clinically. To study the effects of nandrolone decanoate in a model of deficient reinnervation in the rat. In 40 rats, a 40-mm segment of the left median nerve was removed and interposed between the stumps of a sectioned right median nerve. Starting 7 days after nerve grafting and continuing over a 6-month period, we administered nandrolone at a dose of 5 mg/kg/wk to half the rats (n = 20). All rats were assessed behaviorally for grasp function and nociceptive recovery for up to 6 months. At final assessment, reinnervated muscles were tested electrophysiologically and weighed. Results were compared between rats that had received versus not received nandrolone and versus 20 nongrafted controls. Rats in the nandrolone group recovered finger flexion faster. At 90 days postsurgery, they had recovered 42% of normal grasp strength versus just 11% in rats grafted but not treated with nandrolone. At 180 days, the average values for grasp strength recovery in the nandrolone and no-nandrolone groups were 40% and 33% of normal values for controls, respectively. At 180 days, finger flexor muscle twitch strength was 16% higher in treated versus nontreated rats. Thresholds for nociception were not detected in either group 90 days after nerve grafting. At 180 days, nociceptive thresholds were significantly lower in the nandrolone group. Nandrolone decanoate improved functional recovery in a model of deficient reinnervation.

  6. The optimal distance between two electrode tips during recording of compound nerve action potentials in the rat median nerve.

    PubMed

    Li, Yongping; Lao, Jie; Zhao, Xin; Tian, Dong; Zhu, Yi; Wei, Xiaochun

    2014-01-15

    The distance between the two electrode tips can greatly influence the parameters used for recording compound nerve action potentials. To investigate the optimal parameters for these recordings in the rat median nerve, we dissociated the nerve using different methods and compound nerve action potentials were orthodromically or antidromically recorded with different electrode spacings. Compound nerve action potentials could be consistently recorded using a method in which the middle part of the median nerve was intact, with both ends dissociated from the surrounding fascia and a ground wire inserted into the muscle close to the intact part. When the distance between two stimulating electrode tips was increased, the threshold and supramaximal stimulating intensity of compound nerve action potentials were gradually decreased, but the amplitude was not changed significantly. When the distance between two recording electrode tips was increased, the amplitude was gradually increased, but the threshold and supramaximal stimulating intensity exhibited no significant change. Different distances between recording and stimulating sites did not produce significant effects on the aforementioned parameters. A distance of 5 mm between recording and stimulating electrodes and a distance of 10 mm between recording and stimulating sites were found to be optimal for compound nerve action potential recording in the rat median nerve. In addition, the orthodromic compound action potential, with a biphasic waveform that was more stable and displayed less interference (however also required a higher threshold and higher supramaximal stimulus), was found to be superior to the antidromic compound action potential.

  7. The optimal distance between two electrode tips during recording of compound nerve action potentials in the rat median nerve

    PubMed Central

    Li, Yongping; Lao, Jie; Zhao, Xin; Tian, Dong; Zhu, Yi; Wei, Xiaochun

    2014-01-01

    The distance between the two electrode tips can greatly influence the parameters used for recording compound nerve action potentials. To investigate the optimal parameters for these recordings in the rat median nerve, we dissociated the nerve using different methods and compound nerve action potentials were orthodromically or antidromically recorded with different electrode spacings. Compound nerve action potentials could be consistently recorded using a method in which the middle part of the median nerve was intact, with both ends dissociated from the surrounding fascia and a ground wire inserted into the muscle close to the intact part. When the distance between two stimulating electrode tips was increased, the threshold and supramaximal stimulating intensity of compound nerve action potentials were gradually decreased, but the amplitude was not changed significantly. When the distance between two recording electrode tips was increased, the amplitude was gradually increased, but the threshold and supramaximal stimulating intensity exhibited no significant change. Different distances between recording and stimulating sites did not produce significant effects on the aforementioned parameters. A distance of 5 mm between recording and stimulating electrodes and a distance of 10 mm between recording and stimulating sites were found to be optimal for compound nerve action potential recording in the rat median nerve. In addition, the orthodromic compound action potential, with a biphasic waveform that was more stable and displayed less interference (however also required a higher threshold and higher supramaximal stimulus), was found to be superior to the antidromic compound action potential. PMID:25206798

  8. Variation in nerve autograft length increases fibre misdirection and decreases pruning effectiveness: an experimental study in the rat median nerve.

    PubMed

    Bertelli, J A; Taleb, M; Mira, J C; Ghizoni, M F

    2005-09-01

    In the clinical set, autologus nerve grafts are the current option for reconstruction of nerve tissue losses. The length of the nerve graft has been suggested to affect outcomes. Experiments were performed in the rat in order to test this assumption and to detect a possible mechanism to explain differences in recovery. The rat median nerve was repaired by ulnar nerve grafts of different lengths. Rats were evaluated for 12 months by behavioural assessment and histological studies, including ATPase myofibrillary histochemistry and retrograde neuronal labelling. It was demonstrated that graft length interferes in behavioural functional recovery that here correlates to muscle weight recovery. Short nerve grafts recovered faster and better. Reinnervation was not specific either at the trunk level or in the muscle itself. The normal mosaic pattern of Type I muscle fibres was never restored and their number remained largely augmented. An increment in the number of motor fibres was observed after the nerve grafting in a predominantly sensory branch in all groups. This increment was more pronounced in the long graft group. In the postoperative period, about a 20% reduction in the number of misdirected motor fibres occurred in the short nerve graft group only. Variation in the length of nerve grafts interferes in behavioural recovery and increases motor fibres misdirection. Early recovery onset was related to a better outcome, which occurs in the short graft group.

  9. Median Nerve Trauma in a Rat Model of Work-Related Musculoskeletal Disorder

    PubMed Central

    CLARK, BRIAN D.; BARR, ANN E.; SAFADI, FAYEZ F.; BEITMAN, LISA; AL-SHATTI, TALAL; AMIN, MAMTA; GAUGHAN, JOHN P.; BARBE, MARY F.

    2006-01-01

    Anatomical and physiological changes were evaluated in the median nerves of rats trained to perform repetitive reaching. Motor degradation was evident after 4 weeks. ED1-immunoreactive macrophages were seen in the transcarpal region of the median nerve of both forelimbs by 5–6 weeks. Fibrosis, characterized by increased immunoexpression of collagen type I by 8 weeks and connective tissue growth factor by 12 weeks, was evident. The conduction velocity (NCV) within the carpal tunnel showed a modest but significant decline after 9–12 weeks. The lowest NCV values were found in animals that refused to participate in the task for the full time available. Thus, both anatomical and physiological signs of progressive tissue damage were present in this model. These results, together with other recent findings indicate that work-related carpal tunnel syndrome develops through mechanisms that include injury, inflammation, fibrosis and subsequent nerve compression. PMID:12908929

  10. A single trial of transcutaneous electrical nerve stimulation reduces chronic neuropathic pain following median nerve injury in rats.

    PubMed

    Cho, Hwi-Young; Suh, Hye Rim; Han, Hee Chul

    2014-01-01

    Neuropathic pain is a devastating chronic condition and is often induced in the upper limb following nerve injury or damage. Various drugs or surgical methods have been used to manage neuropathic pain; however, these are frequently accompanied by undesirable side effects. Transcutaneous electrical nerve stimulation (TENS) is a safe and non-invasive intervention that has been used to alleviate different types of pain in the clinic, but it is unclear whether TENS can improve chronic neuropathic pain in the upper limb. Thus, the aim of this study was to investigate the effects of a single trial of TENS on chronic neuropathic pain following median nerve injury. Male rats weighing 200-250 g received median nerve-ligation of the right forearm, while the control group received only skin-incision without nerve-ligation. Neuropathic pain-behaviors, including mechanical, cold, and thermal allodynia, were measured for 4 weeks. After the development of chronic neuropathic pain, TENS (100 Hz, 200 µs, sub-motor threshold) or placebo-TENS (sham stimulation) was applied for 20 min to the ipsilateral or contralateral side. Neuropathic pain behavior was assessed before and after intervention. Median nerve-ligation significantly induced and maintained neuropathic pain in the ipsilateral side. TENS application to the ipsilateral side effectively attenuated the three forms of chronic neuropathic pain in the ipsilateral side compared to sham-treated rats (peripheral and central effects), while TENS application to contralateral side only reduced mechanical allodynia in the ipsilateral side (central effect). Our findings demonstrate that TENS can alleviate chronic neuropathic pain following median nerve injury.

  11. Neuronal NOS expression in rat's cuneate nuclei following passive forelimb movements and median nerve stimulation.

    PubMed

    Garifoli, Angelo; Laureanti, Floriana; Coco, Marinella; Perciavalle, Valentina; Maci, Tiziana; Perciavalle, Vincenzo

    2010-12-01

    Nitric oxide (NO) synthase (NOS) has been observed in the Cuneate Nuclei (CN), suggesting a role for NO in the modulation of their neurons' activity. The present study was undertaken to evaluate whether passive movement of forelimb as well as electric stimulation of medial nerve modulate the expression of neuronal isoform of NOS (nNOS) within CN. The experiments were carried out on 21 male Wistar rats, by using two different protocols. In the first group of rats the median nerve was stimulated with high frequency trains (phasic stimulation) or at constant frequency (tonic stimulation); as a control, in the third group, no stimulus was delivered. Moreover, in the second group of rats, we imposed to the animal's left forepaw circular paths at a roughly constant speed (continuous movement), or rapid flexions and extensions of the wrist (sudden movement); as a control, in the third group, no movement was imposed. After the experimental session, free-floating frontal sections of medulla oblongata were processed for nNOS or glutamate (GLU) immunohistochemistry. Phasic stimulation of the median nerve or sudden movements of the forelimb determines a significant decrement of the nNOS-positive neurons within the ipsilateral CN, whereas no effects were observed on GLU positive cells. We have also found a peculiar topographical distribution within IN of nNOS-positive neurons: positive cells were clustered at periphery of some "niches" having circular or elliptical form, with GLU positive cells at center.

  12. Resuscitation therapy for traumatic brain injury-induced coma in rats: mechanisms of median nerve electrical stimulation.

    PubMed

    Feng, Zhen; Zhong, Ying-Jun; Wang, Liang; Wei, Tian-Qi

    2015-04-01

    In this study, rats were put into traumatic brain injury-induced coma and treated with median nerve electrical stimulation. We explored the wake-promoting effect, and possible mechanisms, of median nerve electrical stimulation. Electrical stimulation upregulated the expression levels of orexin-A and its receptor OX1R in the rat prefrontal cortex. Orexin-A expression gradually increased with increasing stimulation, while OX1R expression reached a peak at 12 hours and then decreased. In addition, after the OX1R antagonist, SB334867, was injected into the brain of rats after traumatic brain injury, fewer rats were restored to consciousness, and orexin-A and OXIR expression in the prefrontal cortex was downregulated. Our findings indicate that median nerve electrical stimulation induced an up-regulation of orexin-A and OX1R expression in the prefrontal cortex of traumatic brain injury-induced coma rats, which may be a potential mechanism involved in the wake-promoting effects of median nerve electrical stimulation.

  13. Resuscitation therapy for traumatic brain injury-induced coma in rats: mechanisms of median nerve electrical stimulation

    PubMed Central

    Feng, Zhen; Zhong, Ying-jun; Wang, Liang; Wei, Tian-qi

    2015-01-01

    In this study, rats were put into traumatic brain injury-induced coma and treated with median nerve electrical stimulation. We explored the wake-promoting effect, and possible mechanisms, of median nerve electrical stimulation. Electrical stimulation upregulated the expression levels of orexin-A and its receptor OX1R in the rat prefrontal cortex. Orexin-A expression gradually increased with increasing stimulation, while OX1R expression reached a peak at 12 hours and then decreased. In addition, after the OX1R antagonist, SB334867, was injected into the brain of rats after traumatic brain injury, fewer rats were restored to consciousness, and orexin-A and OXIR expression in the prefrontal cortex was downregulated. Our findings indicate that median nerve electrical stimulation induced an up-regulation of orexin-A and OX1R expression in the prefrontal cortex of traumatic brain injury-induced coma rats, which may be a potential mechanism involved in the wake-promoting effects of median nerve electrical stimulation. PMID:26170820

  14. Collagen nerve wrap for median nerve scarring.

    PubMed

    Kokkalis, Zinon T; Mavrogenis, Andreas F; Ballas, Efstathios G; Papagelopoulos, Panayiotis J; Soucacos, Panayotis N

    2015-02-01

    Nerve wrapping materials have been manufactured to inhibit nerve tissue adhesions and diminish inflammatory and immunologic reactions in nerve surgery. Collagen nerve wrap is a biodegradable type I collagen material that acts as an interface between the nerve and the surrounding tissues. Its main advantage is that it stays in place during the period of tissue healing and is then gradually absorbed once tissue healing is completed. This article presents a surgical technique that used a collagen nerve wrap for the management of median nerve tissue adhesions in 2 patients with advanced carpal tunnel syndrome due to median nerve scarring and adhesions. At last follow-up, both patients had complete resolution with no recurrence of their symptoms. Complications related to the biodegradable material were not observed. Copyright 2015, SLACK Incorporated.

  15. Schwannoma of the median nerve.

    PubMed

    Hubert, Julien; Landes, Geneviève; Tardif, Michèle

    2013-02-01

    A schwannoma is a benign tumour of Schwann cells that presents as a palpable and painless mass on the volar aspect of the hand and wrist. A 44-year-old, right-handed woman, presented for a volar swelling of her right hand. On examination she had a non-pulsatile mass with no fluctuation at the radiopalmar aspect of the right hand, and a soft mass on the volar aspect of the right palm. There was no pain on palpation. An excisional biopsy specimen showed an encapsulated and extrafascicular tumour that originated in the median nerve fascicules. Histological examination showed a median nerve schwannoma measuring 4.0 x 1.5 x 1.2 cm. Differential diagnosis of hand tumours is divided into three categories: tumours of the soft tissue, bone, and skin. Schwannomas of the median nerve make up 0.1%-0.3% of all hand tumours. Symptoms are caused by an entrapment syndrome resulting from the growing tumour. Pain is the most common complaint of schwannomas distal to the wrist. Imaging studies include computed tomography (CT) and magnetic resonance imaging (MRI). It is difficult to differentiate schwanommas from neurofibromas solely on the basis of an MRI. Neurofibroma grows intraneurally and infiltrates the nerve; it has the potential to require resection of all or part of the nerve, leaving a consequent functional deficit. Tumours of the hand are diagnostically challenging and median nerve shwannomas are rare.

  16. A novel rat forelimb model of neuropathic pain produced by partial injury of the median and ulnar nerves.

    PubMed

    Yi, Hanju; Kim, Myung Ah; Back, Seung Keun; Eun, Jong Shin; Na, Heung Sik

    2011-05-01

    The vast majority of human peripheral nerve injuries occur in the upper limb, whereas the most animal studies have been conducted using the hindlimb models of neuropathic pain, involving damages of the sciatic or lumbar spinal nerve(s). We attempted to develop a rat forelimb model of peripheral neuropathy by partial injury of the median and ulnar nerves. The halves of each nerve were transected by microscissors at about 5mm proximal from the elbow joint and behavioral signs of neuropathic pain, such as mechanical and cold allodynia, and heat hyperalgesia, were monitored up to 126 days following nerve injury. Mechanical allodynia was assessed by measuring the forepaw withdrawal threshold to von Frey filaments, and cold allodynia was evaluated by measuring the time spent in lifting or licking the forepaw after applying acetone to it. Heat hyperalgesia was also monitored by investigating the forepaw withdrawal latencies using the Hargreaves' test. After the nerve injury, the experimental animals exhibited long-lasting clear neuropathic pain-like behaviors, such as reduced forepaw withdrawal threshold to von Frey filaments, the increased response duration of the forepaw to acetone application, and the decreased withdrawal latency to radiant heat stimulation. These behaviors were significantly alleviated by administration of gabapentin (5 or 50mg/kg, i.p.) in a dose-dependent manner. Therefore, these abnormal sensitivities are interpreted as the signs of neuropathic pain following injury of the median and ulnar nerves. Our rat forelimb model of neuropathic pain may be useful for studying human neuropathic pain and screening for valuable drug candidates.

  17. Amputation with median nerve redirection (Targeted Reinnervation) reactivates forepaw barrel subfield in rats

    PubMed Central

    Marasco, Paul D.; Kuiken, Todd A.

    2010-01-01

    Prosthetic limbs are difficult to control and do not provide sensory feedback. Targeted Reinnervation was developed as a neural-machine-interface for amputees to address these issues. In Targeted Reinnervation, amputated nerves are redirected to proximal muscles and skin creating nerve interfaces for prosthesis control and sensory feedback. Touching the reinnervated skin causes sensation to be projected to the missing limb. Here we use electrophysiological brain recording in the Sprague-Dawley rat to investigate the changes to somatosensory cortex (S1) following amputation and nerve redirection with the intent to provide insight into the sensory phenomena observed in human Targeted Reinnervation amputees. Recordings revealed that redirected nerves established an expanded representation in S1 which may help to explain the projected sensations that encompass large areas of the hand in Targeted Reinnervation amputees. These results also provide evidence that the reinnervated target skin could serve as a line of communication from a prosthesis to cortical hand processing regions. S1 border regions were simultaneously responsive to reinnervated input and also vibrissae, lower lip and hind-foot, suggesting competition for deactivated cortical territory. Electrically evoked potential latencies from reinnervated skin to cortex suggest direct connection of the redirected afferents to the forepaw processing region of S1. Latencies also provide evidence that the wide-spread reactivation of S1 cortex may arise from central anatomical interconnectivity. Targeted Reinnervation offers the opportunity to examine the cortical plasticity effects when behaviorally important sensory afferents are redirected from their original location to a new skin surface on a different part of the body. PMID:21106839

  18. [Evaluation of grip strength in normal and obese Wistar rats submitted to swimming with overload after median nerve compression].

    PubMed

    Coradinia, Josinéia Gresele; Kakihata, Camila Mayumi Martin; Kunz, Regina Inês; Errero, Tatiane Kamada; Bonfleur, Maria Lúcia; Bertolini, Gladson Ricardo Flor

    2015-01-01

    To verify the functionality through muscle grip strength in animals with obesity induced by monosodium glutamate (MSG) and in control animals, which suffered compression of the right median nerve, and treated with swimming with overload. During the first five days of life, neonatal Wistar rats received subcutaneous injections of MSG. The control group received a hypertonic saline solution. Forty-eight rats were divided into six groups: G1 (control); G2 (control + injury); G3 (control + injury + swimming); G4 (obese); G5 (obese + injury); G6 (obese + injury + swimming). The animals in groups G2, G3, G5 and G6 were submitted to compression of the median nerve and G3 and G6 groups were treated, after injury, with swimming exercise with load for three weeks. The swimming exercise had a progressive duration, according to the week, of 20, 30 and 40minutes. Muscle strength was assessed using a grip strength meter preoperatively and on the 3rd, 7th, 14th and 21st days after surgery. The results were expressed and analyzed using descriptive and inferential statistics. When the grip strength was compared among assessments regardless of group, in the second assessment the animals exhibited lower grip strength. G1 and G4 groups had greater grip strength, compared to G2, G3, G4 and G6. The swimming exercise with overload has not been effective in promoting improvement in muscle grip strength after compression injury of the right median nerve in control and in obese-MSG rats. Copyright © 2013 Elsevier Editora Ltda. All rights reserved.

  19. Anomalous median nerve associated with persistent median artery.

    PubMed Central

    Sañudo, J R; Chikwe, J; Evans, S E

    1994-01-01

    A right human forearm showed persistence of the median artery in combination with anomalies of the median nerve and of the palmar circulation. The median nerve formed a ring enclosing the median artery, gave off its 3rd palmar digital branch in the forearm, and had a high palmar cutaneous nerve origin and a double thenar supply. The superficial palmar arch was incomplete. The median artery extended into the hand, providing the 2nd common palmar digital artery and the artery to the radial side of the index finger. It anastomosed with the radial artery in the 1st web space. Images Fig. 1 Fig. 2 PMID:7961153

  20. Changes in GABA and GABA(B) receptor expressions are involved in neuropathy in the rat cuneate nucleus following median nerve transection.

    PubMed

    Chen, Seu-Hwa; Tsai, Yi-Ju; Lin, Chi-Te; Wang, Hsin-Ying; Li, Shin-Fang; Lue, June-Horng

    2012-06-01

    This study examined the relationship between changes in GABA transmission and behavioral abnormalities after median nerve transection. Following unilateral median nerve transection, the percentage of GABA-like immunoreactive neurons in the cuneate nucleus and that of GABA(B) receptor-like immunoreactive neurons in the dorsal root ganglion in the injured side decreased and reached a nadir at 4 weeks after median nerve transection. Four weeks after bilateral median nerve transection and intraperitoneal application with saline, baclofen (2 mg kg⁻¹), or phaclofen (2 mg kg⁻¹) before unilateral electrical stimulation of the injured median nerve, we investigated the level of neuropeptide Y release and c-Fos expression in the stimulated side of the cuneate nucleus. The neuropeptide Y release level and the number of c-Fos-like immunoreactive neurons in the baclofen group were significantly attenuated, whereas those in the phaclofen group had increased compared to the saline group. These findings indicate that median nerve transection reduces GABA transmission, promoting injury-induced neuropeptide Y release and consequently evoking c-Fos expression in cuneate nucleus neurons. Furthermore, this study used the CatWalk method to assess behavioral abnormalities in rats following median nerve transection. These abnormalities were reversed by baclofen treatment. Overall, the results suggest that baclofen treatment block neuropeptide Y release, subsequently lessening c-Fos expression in cuneate neurons and consequently attenuating neuropathic signal transmission to the thalamus. Copyright © 2012 Wiley Periodicals, Inc.

  1. Shoulder posture and median nerve sliding

    PubMed Central

    Julius, Andrea; Lees, Rebecca; Dilley, Andrew; Lynn, Bruce

    2004-01-01

    Background Patients with upper limb pain often have a slumped sitting position and poor shoulder posture. Pain could be due to poor posture causing mechanical changes (stretch; local pressure) that in turn affect the function of major limb nerves (e.g. median nerve). This study examines (1) whether the individual components of slumped sitting (forward head position, trunk flexion and shoulder protraction) cause median nerve stretch and (2) whether shoulder protraction restricts normal nerve movements. Methods Longitudinal nerve movement was measured using frame-by-frame cross-correlation analysis from high frequency ultrasound images during individual components of slumped sitting. The effects of protraction on nerve movement through the shoulder region were investigated by examining nerve movement in the arm in response to contralateral neck side flexion. Results Neither moving the head forward or trunk flexion caused significant movement of the median nerve. In contrast, 4.3 mm of movement, adding 0.7% strain, occurred in the forearm during shoulder protraction. A delay in movement at the start of protraction and straightening of the nerve trunk provided evidence of unloading with the shoulder flexed and elbow extended and the scapulothoracic joint in neutral. There was a 60% reduction in nerve movement in the arm during contralateral neck side flexion when the shoulder was protracted compared to scapulothoracic neutral. Conclusion Slumped sitting is unlikely to increase nerve strain sufficient to cause changes to nerve function. However, shoulder protraction may place the median nerve at risk of injury, since nerve movement is reduced through the shoulder region when the shoulder is protracted and other joints are moved. Both altered nerve dynamics in response to moving other joints and local changes to blood supply may adversely affect nerve function and increase the risk of developing upper quadrant pain. PMID:15282032

  2. NEURAL FIBROLIPOMA OF THE MEDIAN NERVE.

    PubMed

    Fares, Jawad; Natout, Nizar; Fares, Youssef

    2016-01-01

    We report a rare case of neural fibrolipoma (lipofibromatous hamartoma) of the median nerve of the hand. An 18-year-old male complaining of progressive and chronic macrodactyly of his thumb of the left hand, with neurological complains, was admitted to the hospital. Magnetic resonance (MR) evaluation revealed fibro-fatty infiltration of the median nerve at the level of the carpal tunnel, and the terminal branches of the median nerve in the thumb and index. The pathological examination of excised tissue confirmed the diagnosis of neural fibrolipoma of the terminal branch of the median nerve in his thumb. Imaging is recommended; MR studies on morphological abnormalities must be done in similar cases.

  3. Unusual median nerve schwannoma: a case presentation.

    PubMed

    Anghel, Andrea; Tudose, Irina; Terzea, Dana; Răducu, Laura; Sinescu, Ruxandra Diana

    2014-01-01

    Peripheral nerve sheath tumors are common soft tissue neoplasms and their characterization is often challenging. Although the surgical pathology defines some typical entities, some degree of controversy regarding the classification of these tumors still exists. Newer imagistic and histopathological techniques are crucial for their accurate diagnosis and grading. We present an unusual case of median nerve schwannoma in a young patient, discussing the clinical, surgical and pathological elements, including immunohistochemistry.

  4. Late reconstruction of median nerve palsy.

    PubMed

    Ko, Jia-Wei Kevin; Mirarchi, Adam J

    2012-10-01

    The median nerve provides sensory innervation to the radial aspect of the hand, including the palm, thumb, index, long, and half of the ring fingers. It provides motor innervation to most of the volar forearm musculature and, importantly, to m ost of thenar musculature. The main goal of median nerve reconstructive procedures is to restore thumb opposition. There are a variety of transfers that can achieve this goal but tendon transfers must recreate thumb opposition, which involves 3 basics movements: thumb abduction, flexion, and pronation. Many tendon transfers exist and the choice of tendon transfer should be tailored to the patient's needs. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. High-resolution median nerve sonographic measurements: correlations with median nerve conduction studies in healthy adults.

    PubMed

    Marciniak, Christina; Caldera, Franklin; Welty, Leah; Lai, Jean; Lento, Paul; Feldman, Eric; Sered, Heather; Sayeed, Yusef; Plastaras, Christopher

    2013-12-01

    To study relationships between median wrist and forearm sonographic measurements and median nerve conduction studies. The study population consisted of a prospective convenience sample of healthy adults. Interventions included high-resolution median nerve sonography and median motor and sensory nerve conduction studies. Main outcome measures included median motor nerve compound muscle action potential amplitude, distal latency, and conduction velocity; sensory nerve action potential amplitude and distal latency; and sonographic median nerve cross-sectional area. Median motor nerve and sensory nerve conduction studies of the index finger were performed using standard published techniques. A second examiner blinded to nerve conduction study results used a high-frequency linear array transducer to measure the cross-sectional area of the median nerve at the distal volar wrist crease (carpal tunnel inlet) and forearm (4 cm proximally), measured in the transverse plane on static sonograms. The outer margin of the median nerve was traced at the junction of the hypoechoic fascicles and adjacent outer connective tissue layer. Fifty median nerves were evaluated in 25 participants. The compound muscle action potential amplitude with wrist stimulation was positively related to the cross-sectional area, with the area increasing by 0.195 mm(2) for every millivolt increase in amplitude in the dominant hand (95% confidence interval, 0.020, 0.370 mm(2); P < .05) and 0.247 mm(2) in the nondominant hand (95% confidence interval, 0.035, 0.459 mm(2); P < .05). There was no significant linear association between the wrist median cross-sectional area and median motor and sensory distal latencies. Conduction velocity through the forearm was not significantly linearly associated with the forearm area or forearm-to-wrist area ratio (tapering ratio). The wrist area was inversely related to the sensory nerve action potential amplitude. Although associations were found between median nerve

  6. Mentalis muscle responses to median nerve stimulation.

    PubMed

    Liao, Kwong-Kum; Chen, Jen-Tse; Lai, Kuan-Lin; Kao, Chuen-Der; Lin, Chia-Yi; Liu, Chih-Yang; Lin, Yung-Yang; Shan, Din-E; Wu, Zin-An

    2006-08-31

    Electrical stimulation may produce excitation or inhibition of the motor neurons, as represented the blink reflex and masseter silent period in response to trigeminal nerve stimulation. Clinically, a light touch on the palm may evoke a mentalis muscle response (MMR), i.e. a palmomental reflex. In this study, we attempted to characterize the MMR to median nerve stimulation. Electrical stimulation was applied at the median nerve with recordings at the mentalis muscles. An inhibition study was done with continuous stimuli during muscle contraction (I1 and I2 of MMRaverage). Excitation was done with a single shot during muscle relaxation (MMRsingle) or by continuous stimuli during muscle contraction (E1 and E2 of MMRaverage). The characteristic differences between MMRaverage and MMRsingle were as follows: earlier onset latencies of MMRaverage (MMRaverage < 45 ms; MMRsingle > 60 ms), and a lower amplitude of MMRaverage (MMRaverage < 50 microV; MMRsingle > 150 microV). The receptive field of MMRsingle was widespread over the body surface and that of MMRaverage was limited to the trigeminal, median and index digital nerves. Series of stimuli usually significantly decreased the amplitude of MMRsingle, as a phenomenon of habituation. On the other hand, it was difficult to evoke the earlier response (i.e. MMRaverage) without continuous stimuli and an average technique. MMRaverage had the components of both excitation (E) and inhibition (I); for example, E1-I1-E2-I2 or I1-E2-I2. E2 was the most consistent component. In patients with dorsal column dysfunction, median nerve stimulation could successfully elicit MMRsingle, but not MMRaverage. Contrarily, in patients with pain sensory loss, it was more difficult to reproduce MMRsingle than MMRaverage. It seemed that MMRaverage and MMRsingle did not have equivalents across the different modalities of stimulation.

  7. Laser-activated adhesive films for sutureless median nerve anastomosis.

    PubMed

    Barton, Mathew; Morley, John W; Stoodley, Marcus A; Ng, Kheng-Seong; Piller, Sabine C; Duong, Hong; Mawad, Damia; Mahns, David A; Lauto, Antonio

    2013-12-01

    A novel chitosan adhesive film that incorporates the dye 'Rose Bengal' (RB) was used in conjunction with a green laser to repair transected rat median nerves in vivo. Histology and electrophysiological recording assessed the impact of the laser-adhesive technique on nerves. One week post-operatively, the sham-control group (laser-adhesive technique applied on un-transected nerves) conserved the average number and size of myelinated fibres in comparison to its contralateral side and electrophysiological recordings demonstrated no significant difference with un-operated nerves. Twelve weeks after the laser-adhesive anastomoses, nerves were in continuity with regenerated axons that crossed the anastomotic site. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Lipofibromatous hamartoma of the median nerve

    PubMed Central

    2010-01-01

    Lipofibromatous hamartoma is a rare tumour of peripheral nerves which is characterised by an excessive infiltration of the epineurium and perineurium by fibroadipose tissue. To the best of our knowledge, only approximately 88 cases are reported in the literature. We report a rare case of lipofibromatous hamartoma of the median nerve causing secondary carpal tunnel syndrome in a 25 year old patient. This patient was treated conservatively with decompression and biopsy and experienced a complete resolution of symptoms post-operatively. Magnetic resonance imaging may be used to diagnose this lesion as it has very distinctive characteristics. Multiple conditions have been associated with this lesion and a greater understanding of these associations may clarify the pathogenesis. The architecture of the tumour makes excision very challenging and the surgical management remains controversial. A review of the literature regarding the etiology, pathogenesis and surgical management of lipofibromatous hamartoma is included. PMID:20920178

  9. Employment of the mouse median nerve model for the experimental assessment of peripheral nerve regeneration.

    PubMed

    Tos, P; Ronchi, G; Nicolino, S; Audisio, C; Raimondo, S; Fornaro, M; Battiston, B; Graziani, A; Perroteau, I; Geuna, S

    2008-03-30

    The experimental investigation of nerve regeneration after microsurgical repair is usually carried out in rats, rather than mice, because of the larger sized peripheral nerves. Today however, the availability of genetically modified mice makes the use of this laboratory animal very intriguing for investigating nerve regeneration at a molecular level. In this study we aimed to provide a standardization of the experimental model based on microsurgical direct repair, by 12/0 suture, of the left median nerve in adult male mice. Postoperative recovery was regularly assessed by the grasping test. At day-75 postoperative, regenerated median nerve fibers were analyzed by design-based quantitative morphology and electron microscopy. Yet, sections were immuno-labelled using two axonal antibodies commonly employed for rat nerve fibers. Results indicated that functional recovery begun at day-15 and progressively increased reaching values not significantly different from normal by day-50. Quantitative morphology showed that, at day-75, the number of regenerated nerve fibers was not significantly different in comparison to controls. In contrast, differences were detected in fiber density, mean axon and fiber diameter and myelin thickness which were all significantly lower than controls. Immunohistochemistry showed that axonal markers commonly used for rat nerves studies are effective also for mouse nerves. Similar to the rat, the mouse median nerve model is superior to sciatic nerve model for the minimal impact on animal well-being and the effectiveness of the grasping test for motor function evaluation. The main limitation is the small nerve size which requires advanced microsurgical skills for performing 12/0 epineurial suturing.

  10. Experimental median nerve repair by fresh or frozen nerve autografts and xenografts.

    PubMed

    Accioli De Vaconcellos, Z A; Duchossoy, Y; Kassar-Duchossoy, L; Mira, J C

    1999-01-01

    The authors described the reconstruction of a terminal branch of the brachial plexus (the median nerve) by different kinds of peripheral nerve grafts, in rats. Fresh or frozen autografts from Sprague-Dawley rats and fresh or frozen xenografts from Beagle dogs were used. Three, six, nine and twelve months after grafting, rats underwent histological assessment (muscle, nerve and spinal cord) and simple functional assessment by the grasping test. The immune reaction was prevented by the freezing and thawing method that had rendered xenografts acellular. This process allowed a satisfactory reinnervation of the flexor carpi radialis muscle (FCR) and a function recovery about 75% of control value. Nevertheless, the force recovery in rats that received frozen grafts was slower than those received fresh autografts. Probably, the destruction of cellular elements by freezing produced a deficient environment for nerve regeneration. However, this gap was partially compensated at twelve months after surgery by the maturation and the secondary adaptation of regenerated nerve fibers. Theses results showed that the force recovery is directly correlated to the capability of the nerve fibers to reproduce, histologically, a next to normal nerve pattern.

  11. Median Nerve Palsies due to Injections: A Review.

    PubMed

    Andrea, Andrea; Gonzales, Jocelyn R; Iwanaga, Joe; Oskouian, Rod J; Tubbs, R Shane

    2017-05-29

    Injection nerve palsy (INP) in the median nerve is an iatrogenic peripheral nerve injury that can be inflicted by a faulty intramuscular injection in the median nerve area. The literature reports a 2% incidence of INP among all peripheral nerve injuries. The incidence of INP in developed countries has decreased significantly during the past decade, but the injury appears to remain prevalent in developing countries. A deep understanding of the anatomy of the peripheral nerves, and a precise intramuscular injection technique, have been shown to be vital for preventing INP in the median nerve. Debates continue regarding what, if any, intervention is necessary for injection palsies; and if it is needed, when it should be carried out. In this article, we will review the literature related to median injection nerve palsy and recommended methods of prevention.

  12. The sublime bridge: anatomy and implications in median nerve entrapment.

    PubMed

    Tubbs, R Shane; Marshall, Tyler; Loukas, Marios; Shoja, Mohammadali M; Cohen-Gadol, Aaron A

    2010-07-01

    The sublime bridge is a potential site of entrapment of the median nerve in the forearm. To the authors' knowledge, this structure and its relationship to the median nerve have not been studied. The aim of the present study was to quantitate this structure and elucidate its relationship to the median nerve. Sixty adult cadaveric forearms underwent dissection of the sublime bridge. Relationships of this structure were observed, and measurements of its anatomy were made. The relationship of the median nerve to the sublime bridge was observed with range of motion about the forearm. The sublime bridge was found to be tendinous in the majority (45 [75%]) of specimens and muscular in the remaining forearms (15 [25%]). The maximal mean width of the sublime bridge was 7 cm proximally, and the minimal mean width was 3 cm distally. The mean distance from the medial epicondyle to the apex of the sublime bridge was found to be 8.1 cm. The relation of the median nerve to the bridge was always intimate. On 2 sides (1 left and 1 right) from different male specimens, the median nerve was attached to the deep aspect of the sublime bridge by a strong connective tissue band, thus forming a tunnel on the deep aspect of this structure. With range of motion of the forearm, increased compression of the median nerve by the overlying sublime bridge was seen with extension but no other movement. Based on the authors' study, pronator syndrome is an incorrect term applied to compression of the median nerve at the sublime bridge. This potential site of median nerve compression is distinct and has characteristics that can clinically differentiate it from compression of the median nerve between the heads of the pronator teres. The authors hope that these data will be of use to the surgeon in the evaluation and treatment of patients with proximal median nerve entrapment.

  13. Ultrasonographic median nerve changes after a wheelchair sporting event.

    PubMed

    Impink, Bradley G; Boninger, Michael L; Walker, Heather; Collinger, Jennifer L; Niyonkuru, Christian

    2009-09-01

    To investigate the acute median nerve response to intense wheelchair propulsion by using ultrasonography and to examine the relationship between carpal tunnel syndrome (CTS) signs and symptoms and the acute median nerve response. Case series. Research room at the National Veterans Wheelchair Games. Manual wheelchair users (N=28) competing in wheelchair basketball. Ultrasound images collected before and after a wheelchair basketball game. Median nerve cross-sectional area, flattening ratio, and swelling ratio and changes in these after activity. Comparison of median nerve characteristics and patient characteristics between participants with and without positive physical examination findings and with and without symptoms of CTS. Significant changes in median nerve ultrasound characteristics were noted after activity. The group as a whole showed a significant decrease in cross-sectional area at the radius of 4.05% (P=.023). Participants with positive physical examinations showed significantly different (P=.029) and opposite changes in swelling ratio compared with the normal group. Subjects with CTS symptoms had a significantly (P=.022) greater duration of wheelchair use (17.1 y) compared with the asymptomatic participants (9 y). Manual wheelchair propulsion induces acute changes in median nerve characteristics that can be visualized by using ultrasound. Studying the acute median nerve response may be useful for optimizing various interventions, such as wheelchair set up or propulsion training, to decrease both acute and chronic median nerve damage and the likelihood of developing CTS.

  14. Tendon transfers for radial and median nerve palsies.

    PubMed

    Kozin, Scott H

    2005-01-01

    Paralysis or irreparable injury to the radial or median nerve results in considerable impairment of hand function that directly affects activities of daily living. Radial nerve loss prevents wrist and digit extension, which hinders object acquisition and release. Median nerve loss deprives the hand of thumb function, especially opposition, which impedes prehension. Tendon transfers to restore function are indicated when nerve recovery is no longer expected. Tendon transfer can re-establish active movement and enhance function. The maximum benefit after tendon transfer, however, requires a close working relationship among patient, therapist, and physician. This article will highlight the surgical principles and rehabilitative process to achieve this goal.

  15. Sensoric protection after median nerve injury: babysitter-procedure prevents muscular atrophy and improves neuronal recovery.

    PubMed

    Beck-Broichsitter, Benedicta E; Becker, Stephan T; Lamia, Androniki; Fregnan, Federica; Geuna, Stefano; Sinis, Nektarios

    2014-01-01

    The babysitter-procedure might offer an alternative when nerve reconstruction is delayed in order to overcome muscular atrophy due to denervation. In this study we aimed to show that a sensomotoric babysitter-procedure after median nerve injury is capable of preserving irreversible muscular atrophy. The median nerve of 20 female Wistar rats was denervated. 10 animals received a sensory protection with the N. cutaneous brachii. After six weeks the median nerve was reconstructed by autologous nerve grafting from the contralateral median nerve in the babysitter and the control groups. Grasping tests measured functional recovery over 15 weeks. At the end of the observation period the weight of the flexor digitorum sublimis muscle was determined. The median nerve was excised for histological examinations. Muscle weight (P < 0.0001) was significantly superior in the babysitter group compared to the control group at the end of the study. The histological evaluation revealed a significantly higher diameter of axons (P = 0.0194), nerve fiber (P = 0.0409), and nerve surface (P = 0.0184) in the babysitter group. We conclude that sensory protection of a motor nerve is capable of preserving muscule weight and we may presume that metabolism of the sensory nerve was sufficient to keep the target muscle's weight and vitality.

  16. Sensoric Protection after Median Nerve Injury: Babysitter-Procedure Prevents Muscular Atrophy and Improves Neuronal Recovery

    PubMed Central

    Beck-Broichsitter, Benedicta E.; Becker, Stephan T.; Lamia, Androniki; Fregnan, Federica; Sinis, Nektarios

    2014-01-01

    The babysitter-procedure might offer an alternative when nerve reconstruction is delayed in order to overcome muscular atrophy due to denervation. In this study we aimed to show that a sensomotoric babysitter-procedure after median nerve injury is capable of preserving irreversible muscular atrophy. The median nerve of 20 female Wistar rats was denervated. 10 animals received a sensory protection with the N. cutaneous brachii. After six weeks the median nerve was reconstructed by autologous nerve grafting from the contralateral median nerve in the babysitter and the control groups. Grasping tests measured functional recovery over 15 weeks. At the end of the observation period the weight of the flexor digitorum sublimis muscle was determined. The median nerve was excised for histological examinations. Muscle weight (P < 0.0001) was significantly superior in the babysitter group compared to the control group at the end of the study. The histological evaluation revealed a significantly higher diameter of axons (P = 0.0194), nerve fiber (P = 0.0409), and nerve surface (P = 0.0184) in the babysitter group. We conclude that sensory protection of a motor nerve is capable of preserving muscule weight and we may presume that metabolism of the sensory nerve was sufficient to keep the target muscle's weight and vitality. PMID:25133176

  17. Median nerve biodegradable wrapping : Clinical outcome of 10 patients.

    PubMed

    Kokkalis, S T; Mavrogenis, A F; Vottis, C; Papatheodorou, L; Papagelopoulos, P J; Soucacos, P N; Sotereanos, D G

    2016-08-01

    Nerve wrap protectors are bioabsorbable synthetic materials made of collagen or extracellular matrix that provide a non-constricting encasement for injured peripheral nerves. They are designed to be used as an interface between the nerve and the surrounding tissue. After hydrated, they transform into a soft, pliable, nonfriable, easy to handle porous conduit. The wall of the nerve wrap has a longitudinal slit that allows to be placed around the injured nerve. Τhis article presents the surgical technique for median nerve neurolysis and nerve coverage using a collagen or an extracellular matrix nerve wrap protector in 10 patients with recurrent or persistent carpal -tunnel syndrome. All patients had a mean of three previous open carpal tunnel operations, which were not successful. The mean follow-up was 3 years. -Under axillary nerve block anaesthesia with the use of -pneumatic tourniquet, a standard open carpal tunnel approach was done incorporating the previous incision. Scar tissue was excised in a healthy bed and the median nerve was thoroughly released with external neurolysis. An appropriate length of nerve wrap protector was cut longitudinally according to the length of nerve release. The nerve wrap was loosely sutured with separate polypropylene sutures No. 7-0. A volar splint was applied for a mean of 2 weeks followed by progressive passive and active range of motion rehabilitation exercises of the wrist and fingers. At the last follow-up, all patients showed improvement of clinical symptoms, static two-point discrimination test and median nerve conduction studies, and absence of Tinel sign. Differences in outcome and complications with respect to the nerve wrap materials used were not observed.

  18. Clinical Outcomes following median to radial nerve transfers

    PubMed Central

    Ray, Wilson Z.; Mackinnon, Susan E.

    2010-01-01

    Purpose In this study the authors evaluate the clinical outcomes in patients with radial nerve palsy who underwent nerve transfers utilizing redundant fascicles of median nerve (innervating the flexor digitorum superficialis and flexor carpi radialis muscles) to the posterior interosseous nerve and the nerve to the extensor carpi radialis brevis. Methods A retrospective review of the clinical records of 19 patients with radial nerve injuries who underwent nerve transfer procedures using the median nerve as a donor nerve were included. All patients were evaluated using the Medical Research Council (MRC) grading system. Results The mean age of patients was 41 years (range 17 – 78 years). All patients received at least 12 months of follow-up (20.3 ± 5.8 months). Surgery was performed at a mean of 5.7 ± 1.9 months post-injury. Post-operative functional evaluation was graded according to the following scale: grades MRC 0/5 - MRC 2/5 were considered poor outcomes, while MRC of 3/5 was a fair result, MRC grade 4/5 was a good result, and grade 4+/5 was considered an excellent outcome. Seventeen patients (89%) had a complete radial nerve palsy while two patients (11%) had intact wrist extension but no finger or thumb extension. Post-operatively all patients except one had good to excellent recovery of wrist extension. Twelve patients recovered good to excellent finger and thumb extension, two patients had fair recovery, five patients had a poor recovery. Conclusions The radial nerve is a commonly injured nerve, causing significant morbidity in affected patients. The median nerve provides a reliable source of donor nerve fascicles for radial nerve reinnervation. This transfer was first performed in 1999 and evolved over the subsequent decade. The important nuances of both surgical technique and motor re-education critical for to the success of this transfer have been identified and are discussed. PMID:21168979

  19. Median nerve (anatomical variations) and carpal tunel syndrome - revisited.

    PubMed

    Mizia, Ewa; Tomaszewski, Krzysztof; Depukat, Pawel; Klimek-Piotrowska, Wieslawa; Pasternak, Artur; Mroz, Izabela; Bonczar, Tomasz

    2013-01-01

    Carpal tunnel syndrome belongs to the most common causative factors of surgical interventions in the wrist region. Anatomy of carpal tunnel and median nerve is a subject of current revision. Authors paid attention to etiology of the syndrome based on review of literature and their own anatomical studies. They remind basic knowledge on the median nerve and indicate that only based on number of dissections a good orthopedic surgeon may acquire experience necessary to perform procedures in a most appropriate way.

  20. Has the median nerve involvement in rheumatoid arthritis been overemphasised?

    PubMed

    Sakthiswary, Rajalingham; Singh, Rajesh

    2016-08-30

    Rheumatoid arthritis (RA) is a well and widely recognised cause of carpal tunnel syndrome (CTS). In the rheumatoid wrist, synovial expansion, joint erosions and ligamentous laxity result in compression of the median nerve due to increased intracarpal pressure. We evaluated the published studies to determine the prevalence of CTS and the characteristics of the median nerve in RA and its association with clinical parameters such as disease activity, disease duration and seropositivity. A total of 13 studies met the eligibility criteria. Pooled data from 8 studies with random selection of RA patients revealed that 86 out of 1561 (5.5%) subjects had CTS. Subclinical CTS, on the other hand, had a pooled prevalence of 14.0% (30/215). The cross sectional area of the median nerve of the RA patients without CTS were similar to the healthy controls. The vast majority of the studies (8/13) disclosed no significant relationship between the median nerve findings and the clinical or laboratory parameters in RA. The link between RA and the median nerve abnormalities has been overemphasised throughout the literature. The prevalence of CTS in RA is similar to the general population without any correlation between the median nerve characteristics and the clinical parameters of RA. Copyright © 2016. Published by Elsevier Editora Ltda.

  1. Has the median nerve involvement in rheumatoid arthritis been overemphasized?

    PubMed

    Sakthiswary, Rajalingham; Singh, Rajesh

    Rheumatoid arthritis (RA) is a well and widely recognized cause of carpal tunnel syndrome (CTS). In the rheumatoid wrist, synovial expansion, joint erosions and ligamentous laxity result in compression of the median nerve due to increased intracarpal pressure. We evaluated the published studies to determine the prevalence of CTS and the characteristics of the median nerve in RA and its association with clinical parameters such as disease activity, disease duration and seropositivity. A total of 13 studies met the eligibility criteria. Pooled data from 8 studies with random selection of RA patients revealed that 86 out of 1561 (5.5%) subjects had CTS. Subclinical CTS, on the other hand, had a pooled prevalence of 14.0% (30/215). The cross sectional area of the median nerve of the RA patients without CTS were similar to the healthy controls. The vast majority of the studies (8/13) disclosed no significant relationship between the median nerve findings and the clinical or laboratory parameters in RA. The link between RA and the median nerve abnormalities has been overemphasized throughout the literature. The prevalence of CTS in RA is similar to the general population without any correlation between the median nerve characteristics and the clinical parameters of RA. Copyright © 2016 Elsevier Editora Ltda. All rights reserved.

  2. Myofibroma in the palm presenting with median nerve compression symptoms.

    PubMed

    Sarkozy, Heidi; Kulber, David A

    2014-08-01

    A myofibroma is a benign proliferation of myofibroblasts in the connective tissue. Solitary myofibromas are a rare finding especially in an adult. We report a case of a 23-year-old man presenting with an enlarging mass over his right palm. The patient is an active weight lifter. He reported numbness and tingling in the median nerve distribution. Nerve conduction studies and magnetic resonance imaging scans suggested a tumor involving or compressing the median nerve. The final diagnosis of myofibroma was made only after the histopathological diagnosis.

  3. [Case of median nerve paralysis after hepatic segmentectomy].

    PubMed

    Yoshimatsu, Aya; Hoshi, Takuo; Tanaka, Makoto

    2011-05-01

    We report a case of a median nerve palsy. Hepatic segmentectomy and lymphnode dissection were performed in a 21-year-old man for multiple liver and retroperitoneal lymph nodes metastasis of seminoma. After surgery, patient complained of motor paralysis and hypesthesia of the left palm side of the thumb, first finger and radial half of the middle finger. He was diagnosed as having median nerve palsy. Motor paralysis and hypesthesia gradually disappeared over the two weeks after surgery. We should pay attention to appropriate positioning of the arm during surgery, and preoperative use of paclitaxel needs to be considered as etiology for perioperative peripheral nerve palsy.

  4. Median nerve superficial to the transverse carpal ligament.

    PubMed

    Amanatullah, Derek F; Gaskin, Alexis D; Allen, Robert H

    2015-01-01

    Recurrent carpal tunnel syndrome occurs in up to 12% of cases after carpal tunnel release. Recurrent carpal tunnel syndrome is defined as recurrence of classic symptoms confirmed by electrodiagnostic studies after a symptom-free interval of a minimum of 6 months, as opposed to persistent carpal tunnel syndrome, where a symptom-free interval never occurs after carpal tunnel release, which is attributed to incomplete release of the transverse carpal ligament. The most common causes of recurrent carpal tunnel syndrome requiring reoperation are incomplete release of the transverse carpal ligament and scarring of the median nerve to the surrounding structures. Surgical exploration, release of the reconstituted transverse carpal ligament, and freeing of the median nerve from constricting scar will usually result in symptom relief. The authors describe an unusual presentation of recurrent carpal tunnel syndrome with healing of the transverse carpal ligament dorsal to the median nerve, trapping the median nerve in the subcutaneous tissue. Hand surgeons must be aware of this anomalous location when performing revision carpal tunnel release. The surgeon must locate the median nerve proximally in normal tissue before proceeding distally to avoid iatrogenic injury during revision carpal tunnel release. Copyright 2015, SLACK Incorporated.

  5. Iatrogenic selective lesion of the median nerve at the elbow.

    PubMed

    Di Fabio, Roberto; Casali, Carlo; Pierelli, Francesco

    2010-03-01

    A lesion of the median nerve may occur as a consequence of a compression by a haematoma or for a direct damage of the axons caused by a needle insertion. To date, no investigation reported a very selective lesion of the median nerve at the elbow, with the suffering limited only to the fibres for the first digit. A 53 year-old left-handed violinist underwent an arterial blood gas drawing. The patient complained immediately of an electrical shock impression going down the arm, followed by pin sensation into the first finger. A tingling sensation associated with numbness in the first fingertip and difficulty in the index-thumb pinch became progressively evident. The ENG-EMG findings showed an impairment mainly of the sensory fibres innervating the first digit and a drop of the motor action potential amplitude when the nerve was stimulated at the elbow. We reported a very partial lesion of the left median nerve at the elbow in a violinist who had a selective involvement of the fibres for his first digit. Even minimal lesions of the median nerve may impair severely the quality of life of patients.

  6. Median to radial nerve transfer for treatment of radial nerve palsy. Case report.

    PubMed

    Mackinnon, Susan E; Roque, Brandon; Tung, Thomas H

    2007-09-01

    The purpose of this study is to report a surgical technique of nerve transfer to restore radial nerve function after a complete palsy due to a proximal injury to the radial nerve. The authors report the case of a patient who underwent direct nerve transfer of redundant or expendable motor branches of the median nerve in the proximal forearm to the extensor carpi radialis brevis and the posterior interosseous branches of the radial nerve. Assessment included degree of recovery of wrist and finger extension, and median nerve function including pinch and grip strength. Clinical evidence of reinnervation was noted at 6 months postoperatively. The follow-up period was 18 months. Recovery of finger and wrist extension was almost complete with Grade 4/5 strength. Pinch and grip strength were improved postoperatively. No motor or sensory deficits related to the median nerve were noted, and the patient is very satisfied with her degree of functional restoration. Transfer of redundant synergistic motor branches of the median nerve can successfully reinnervate the finger and wrist extensor muscles to restore radial nerve function. This median to radial nerve transfer offers an alternative to nerve repair, graft, or tendon transfer for the treatment of radial nerve palsy.

  7. Median nerve neuropraxia by a large false brachial artery aneurysm.

    PubMed

    Lijftogt, Niki; Cancrinus, Ernst; Hoogervorst, Erwin L J; van de Mortel, Rob H W; de Vries, Jean-Paul P M

    2014-10-01

    Peripheral nerve compression is a rare complication of an iatrogenic false brachial artery aneurysm. We present a 72-year-old patient with median nerve compression due to a false brachial artery aneurysm after removal of an arterial catheter. Surgical exclusion of the false aneurysm was performed in order to release traction of the median nerve. At 3-month assessment, moderate hand recovery in function and sensibility was noted. In the case of neuropraxia of the upper extremity, following a history of hospital stay and arterial lining or catheterization, compression due to pseudoaneurysm should be considered a probable cause directly at presentation. Early recognition and treatment is essential to avoid permanent neurological deficit. © The Author(s) 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  8. Relation of wrist angles to median nerve conduction studies.

    PubMed

    Cuevas-Trisan, Ramon L; Ojeda-Rodriguez, Aileen G

    2006-01-01

    To measure the changes in median nerve conduction parameters at various angles of wrist flexion and extension. We studied 8 patients with carpal tunnel syndrome (CTS) and 4 subjects (5 hands) without the condition (controls). Conduction parameters were measured with the wrist in neutral position and at different wrist angles. Onset motor latency increased in both groups with wrist extension and decreased with wrist flexion. Sensory onset latency decreased in both groups with wrist flexion. Compound Muscle Action Potential (CMAP) amplitude increased with wrist flexion for both groups. Wrist extension resulted in reduction of the CMAP amplitude in controls; however, for the CTS group it increased for the first 30 degrees and then decreased. Sensory Nerve Action Potential (SNAP) amplitude increased with wrist flexion and decreased with wrist extension in both groups. Median nerve conduction parameters improve with wrist flexion and generally worsen with extension.

  9. Fascicular Topography of the Human Median Nerve for Neuroprosthetic Surgery

    PubMed Central

    Delgado-Martínez, Ignacio; Badia, Jordi; Pascual-Font, Arán; Rodríguez-Baeza, Alfonso; Navarro, Xavier

    2016-01-01

    One of the most sought-after applications of neuroengineering is the communication between the arm and an artificial prosthetic device for the replacement of an amputated hand or the treatment of peripheral nerve injuries. For that, an electrode is placed around or inside the median nerve to serve as interface for recording and stimulation of nerve signals coming from the fascicles that innervate the muscles responsible for hand movements. Due to the lack of a standard procedure, the electrode implantation by the surgeon is strongly based on intuition, which may result in poor performance of the neuroprosthesis because of the suboptimal location of the neural interface. To provide morphological data that can aid the neuroprosthetic surgeon with this procedure, we investigated the fascicular topography of the human median nerve along the forearm and upper arm. We first performed a description of the fascicular content and branching patterns along the length of the arm. Next we built a 3D reconstruction of the median nerve so we could analyze the fascicle morphological features in relation to the arm level. Finally, we characterized the motor content of the median nerve fascicles in the upper arm. Collectively, these results indicate that fascicular organization occurs in a short segment distal to the epicondyles and remains unaltered until the muscular branches leave the main trunk. Based on our results, overall recommendations based on electrode type and implant location can be drawn to help and aid the neuroprosthetic procedure. Invasive interfaces would be more convenient for the upper arm and the most proximal third of the forearm. Epineural electrodes seem to be most suitable for the forearm segment after fascicles have been divided from the main trunk. PMID:27445660

  10. Fascicular Topography of the Human Median Nerve for Neuroprosthetic Surgery.

    PubMed

    Delgado-Martínez, Ignacio; Badia, Jordi; Pascual-Font, Arán; Rodríguez-Baeza, Alfonso; Navarro, Xavier

    2016-01-01

    One of the most sought-after applications of neuroengineering is the communication between the arm and an artificial prosthetic device for the replacement of an amputated hand or the treatment of peripheral nerve injuries. For that, an electrode is placed around or inside the median nerve to serve as interface for recording and stimulation of nerve signals coming from the fascicles that innervate the muscles responsible for hand movements. Due to the lack of a standard procedure, the electrode implantation by the surgeon is strongly based on intuition, which may result in poor performance of the neuroprosthesis because of the suboptimal location of the neural interface. To provide morphological data that can aid the neuroprosthetic surgeon with this procedure, we investigated the fascicular topography of the human median nerve along the forearm and upper arm. We first performed a description of the fascicular content and branching patterns along the length of the arm. Next we built a 3D reconstruction of the median nerve so we could analyze the fascicle morphological features in relation to the arm level. Finally, we characterized the motor content of the median nerve fascicles in the upper arm. Collectively, these results indicate that fascicular organization occurs in a short segment distal to the epicondyles and remains unaltered until the muscular branches leave the main trunk. Based on our results, overall recommendations based on electrode type and implant location can be drawn to help and aid the neuroprosthetic procedure. Invasive interfaces would be more convenient for the upper arm and the most proximal third of the forearm. Epineural electrodes seem to be most suitable for the forearm segment after fascicles have been divided from the main trunk.

  11. Inter-hemispheric plasticity in patients with median nerve injury.

    PubMed

    Fornander, Lotta; Nyman, Torbjörn; Hansson, Thomas; Brismar, Tom; Engström, Maria

    2016-08-15

    Peripheral nerve injuries result in reorganization within the contralateral hemisphere. Furthermore, recent animal and human studies have suggested that the plastic changes in response to peripheral nerve injury also include several areas of the ipsilateral hemisphere. The objective of this study was to map the inter-hemispheric plasticity in response to median nerve injury, to investigate normal differences in contra- and ipsilateral activation, and to study the impact of event-related or blocked functional magnetic resonance imaging (fMRI) design on ipsilateral activation. Four patients with median nerve injury at the wrist (injured and epineurally sutured >2 years earlier) and ten healthy volunteers were included. 3T fMRI was used to map the hemodynamic response to brain activity during tactile stimulation of the fingers, and a laterality index (LI) was calculated. Stimulation of Digits II-III of the injured hand resulted in a reduction in contralateral activation in the somatosensory area SI. Patients had a lower LI (0.21±0.15) compared to healthy controls (0.60±0.26) indicating greater ipsilateral activation of the primary somatosensory cortex. The spatial dispersion of the coordinates for areas SI and SII was larger in the ipsilateral than in the contralateral hemisphere in the healthy controls, and was increased in the contralateral hemisphere of the patients compared to the healthy controls. There was no difference in LI between the event-related and blocked paradigms. In conclusion, patients with median nerve injury have increased ipsilateral SI area activation, and spatially more dispersed contralateral SI activation during tactile stimulation of their injured hand. In normal subjects ipsilateral activation has larger spatial distribution than the contralateral. Previous findings in patients performed with the blocked fMRI paradigm were confirmed. The increase in ipsilateral SI activation may be due to an interhemispheric disinhibition associated with

  12. Tortuous axillary artery aneurysm causing median nerve compression.

    PubMed

    Ortiz-Pomales, Yan; Smith, Jennifer; Weiss, Jeffrey; Casey, Kevin

    2014-01-01

    Axillary artery aneurysms are rare entities that warrant surgical intervention. Reported complications include thrombosis, distal embolization, and debilitating neurologic symptoms caused by median nerve compression. Common etiologies include trauma or repetition injuries. Less recognized associations include atherosclerotic, connective tissue, or mycotic processes. We report a case of a rare tortuous axillary artery aneurysm causing neurologic symptoms in a woman with an unused arteriovenous fistula. Published by Elsevier Inc.

  13. Ultrasound elastography assessment of the median nerve in leprosy patients.

    PubMed

    Nogueira-Barbosa, Marcello H; Lugão, Helena B; Gregio-Júnior, Everaldo; Crema, Michel D; Kobayashi, Mariana T T; Frade, Marco A C; Pavan, Theo Z; Carneiro, Antonio A O

    2017-09-01

    We sought to compare median nerve elasticity between leprosy patients (LPs) and healthy volunteers (HVs) using ultrasound elastography (UE). Two radiologists independently measured the strain ratio of the median nerve/flexor digitorum superficialis muscle (MN/FDSM) of 18 LP and 18 HV using real-time freehand UE. Statistical analysis included intra-class correlation coefficients (ICC) and Mann-Whitney test. The MN/FDSM strain ratios of the LP and HV were 2.66 ± 1.30 and 3.52 ± 0.93, respectively (P <  0.05). We observed a significantly lower MN/FDSM strain ratio in LP with reactions (types 1 and 2 cutaneous reactions associated with or without neuritis) (2.30 ± 0.91) compared with LP without reactions (3.60 ± 1.70). We found no significant differences between HV and LP without reactions. The intra- and inter-observer ICCs were 0.50 (95% confidence interval [CI], 0.11-0.72) and 0.34 (95% CI, 0.28-0.52), respectively. MN/FDSM strain ratios were significantly lower in LP with reactions. UE may be useful for nerve elasticity evaluation in leprosy. Muscle Nerve 56: 393-398, 2017. © 2016 Wiley Periodicals, Inc.

  14. Meaningful power grip recovery after salvage reconstruction of a median nerve avulsion injury with a pedicled vascularized ulnar nerve

    PubMed Central

    Van Slyke, Aaron C; Jansen, Leigh A; Hynes, Sally; Hicks, Jane; Bristol, Sean; Carr, Nicholas

    2015-01-01

    In cases of median nerve injury alongside an unsalvageable ulnar nerve, a vascularized ulnar nerve graft to reconstruct the median nerve is a viable option. While restoration of median nerve sensation is consistently reported, recovery of significant motor function is less frequently observed. The authors report a case involving a previously healthy man who sustained upper arm segmental median and ulnar nerve injuries and, after failure of sural nerve grafts, was treated with a pedicled vascularized ulnar nerve graft to restore median nerve function. Long-term follow-up showed near full fist, with 12 kg of grip strength, key pinch with 1.5 kg of strength and protective sensation in the median nerve distribution. The present case demonstrates that pedicled ulnar vascularized nerve grafts can provide significant improvements to median nerve sensory and motor function in a heavily scarred environment. PMID:26665144

  15. Morphologic Characterization of Intraneural Flow Associated With Median Nerve Pathology

    PubMed Central

    Evans, Kevin D.; Volz, Kevin R.; Hutmire, Cristina; Roll, Shawn C.

    2013-01-01

    A prospective cohort of 47 symptomatic patients who reported for nerve conduction studies and 44 asymptomatic controls was examined with sonography to evaluate the median nerve. Doppler studies of the median nerve were collected with handheld sonography equipment and a 12-MHz linear broadband transducer. Strict inclusion criteria were established for assessing 435 waveforms from 166 wrists. Two sonographers agreed that 245 waveforms met the a priori criteria and analyzed the corresponding data. Spectral Doppler waveforms provided direct quantitative and qualitative data for comparison with indirect provocative testing results. These Doppler data were compared between the recruitment groups. No statistical difference existed in waveforms between the groups (P < .05). Trending of the overall data indicated that as the number of positive provocative tests increased, the mean peak systolic velocity within the carpal tunnel (mid) also increased, whereas the proximal mean peak systolic velocity decreased. However, by using multiple provocative tests as an indirect comparative measure, researchers may find mean peak spectral velocity at the carpal tunnel inlet a helpful direct measure in identifying patients with carpal tunnel syndrome. PMID:23772421

  16. Morphologic Characterization of Intraneural Flow Associated With Median Nerve Pathology.

    PubMed

    Evans, Kevin D; Volz, Kevin R; Hutmire, Cristina; Roll, Shawn C

    2012-01-01

    A prospective cohort of 47 symptomatic patients who reported for nerve conduction studies and 44 asymptomatic controls was examined with sonography to evaluate the median nerve. Doppler studies of the median nerve were collected with handheld sonography equipment and a 12-MHz linear broadband transducer. Strict inclusion criteria were established for assessing 435 waveforms from 166 wrists. Two sonographers agreed that 245 waveforms met the a priori criteria and analyzed the corresponding data. Spectral Doppler waveforms provided direct quantitative and qualitative data for comparison with indirect provocative testing results. These Doppler data were compared between the recruitment groups. No statistical difference existed in waveforms between the groups (P < .05). Trending of the overall data indicated that as the number of positive provocative tests increased, the mean peak systolic velocity within the carpal tunnel (mid) also increased, whereas the proximal mean peak systolic velocity decreased. However, by using multiple provocative tests as an indirect comparative measure, researchers may find mean peak spectral velocity at the carpal tunnel inlet a helpful direct measure in identifying patients with carpal tunnel syndrome.

  17. Peripheral nerve lipoma: Case report of an intraneural lipoma of the median nerve and literature review

    PubMed Central

    Teles, Alisson Roberto; Finger, Guilherme; Schuster, Marcelo N.; Gobbato, Pedro Luis

    2016-01-01

    Adipose lesions rarely affect the peripheral nerves. This can occur in two different ways: Direct compression by an extraneural lipoma, or by a lipoma originated from the adipose cells located inside the nerve. Since its first description, many terms have been used in the literature to mention intraneural lipomatous lesions. In this article, the authors report a case of a 62-year-old female who presented with an intraneural median nerve lipoma and review the literature concerning the classification of adipose lesions of the nerve, radiological diagnosis and treatment. PMID:27695575

  18. Resection and nerve grafting of a lipofibrohamartoma of the median nerve: case report.

    PubMed

    Cherqui, Alice; Sulaiman, Wale A R; Kline, David G

    2009-10-01

    Our patient's symptomatology, history, physical examination, diagnosis, management, and functional outcome 1 year after surgical repair is presented and discussed in light of the current literature on lipofibrohamartomas. A 3-year-old boy presented to the Louisiana State University Nerve Clinic for evaluation and management because he was experiencing progressive symptoms of left hand swelling, dysesthesia, and impaired motor function. Physical examination demonstrated median nerve distribution motor impairment. Electromyographic/nerve conduction velocity studies also showed severely reduced conduction and amplitude of the median nerve response, and the magnetic resonance imaging findings were highly suggestive of lipofibrohamartoma. Hence, the presumed diagnosis was lipofibrohamartoma on the basis of imaging characteristics, location, and patient's age. The patient was brought to the operating room with the objectives of carpal tunnel release and biopsy. However, routine intraoperative nerve action potential recordings showed no or very poor responses, consistent with significant loss of median nerve function. On the basis of the intraoperative nerve action potentials, we opted to resect the tumor back to healthy median nerve fascicles and to perform graft repairs. Surgery proceeded uneventfully, without any complications. Pathology confirmed the diagnosis of lipofibrohamartoma. At 18 months postoperatively, the patient had excellent left hand function. On the basis of our experience with this patient, we believe that intraoperative nerve action potentials and the availability of usable proximal and distal nerve fascicles (which may be discernible on diagnostic imaging) are key factors in deciding whether a lipofibrohamartoma needs to be repaired or decompressed/biopsied. As illustrated by our case, we believe that resection and graft repair may be the best treatment option for some of these patients, and perhaps more so for pediatric patients.

  19. Morphometric studies of the muscular branch of the median nerve.

    PubMed Central

    Olave, E; Prates, J C; Gabrielli, C; Pardi, P

    1996-01-01

    The branch from the median nerve to the thenar muscles has a proximal and lateral (recurrent) course and is vulnerable to lesions that affect these muscles. Because of its anatomical-clinical importance, this branch was studied in 60 palmar regions from 30 cadavers of adult individuals of both sexes, aged between 23 and 77 y. It arose from the lateral branch of the median nerve in 83.3% of the cases. Its origin was distal to the flexor retinaculum in 48.3%, at the distal margin of the retinaculum in 31.6%, in the carpal tunnel in 18.3% and proximal to the retinaculum in 1.7%; it pierced the retinaculum in 15%. The point of recurrence of the branch was localised topographically to 34.6 +/- 3.6 mm from the distal wrist crease; the angle between its recurrent course and the longitudinal axis of the hand averaged 66.8 degrees. In 50% of the cases the muscular branch innervated abductor pollicis brevis (APB), opponens pollicis (OP) and the superficial head of flexor pollicis brevis (FPB), in 40% it supplied only APB and OP, and in 10% a short muscular branch gave rise to independent branches in the palm and which supplied APB, OP and the superficial head of FPB. The so called "accessory thenar branch' was found in 38.3%. Images Fig. 1 Fig. 2 PMID:8886966

  20. Giant lipoma of the hand causing median nerve compression.

    PubMed

    Clesham, Kevin; Galbraith, John Gerard; Ramasamy, Ashok; Karkuri, Ahmed

    2017-06-28

    Lipomas are benign neoplasms derived from adipose tissue composed of mature adipocytes. They account for almost 50% of all soft-tissue neoplasms and occur in up to 2% of the population. They usually present asymptomatically as solitary discrete mobile lumps found most commonly on the neck, upper back, proximal limbs and chest. In less than 1% of cases, they can be found in the distal extremities.We discuss the case of a 65-year-old man who presented with a 2-year history of a slowly enlarging left palm swelling, with recent-onset numbness and loss of power in the distribution of the median nerve. MRI studies showed that the 5×4×2.7 cm lipoma had a component extending into the distal aspect of the carpal tunnel, compressing the median nerve. It was successfully excised, and at follow-up the patient reported complete resolution of his symptoms. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  1. Neurosteroid Allopregnanolone Suppresses Median Nerve Injury-induced Mechanical Hypersensitivity and Glial Extracellular Signal-regulated Kinase Activation through γ-Aminobutyric Acid Type A Receptor Modulation in the Rat Cuneate Nucleus.

    PubMed

    Huang, Chun-Ta; Chen, Seu-Hwa; Lue, June-Horng; Chang, Chi-Fen; Wen, Wen-Hsin; Tsai, Yi-Ju

    2016-12-01

    Mechanisms underlying neuropathic pain relief by the neurosteroid allopregnanolone remain uncertain. We investigated if allopregnanolone attenuates glial extracellular signal-regulated kinase (ERK) activation in the cuneate nucleus (CN) concomitant with neuropathic pain relief in median nerve chronic constriction injury (CCI) model rats. We examined the time course and cellular localization of phosphorylated ERK (p-ERK) in CN after CCI. We subsequently employed microinjection of a mitogen-activated protein kinase kinase (ERK kinase) inhibitor, PD98059, to clarify the role of ERK phosphorylation in neuropathic pain development. Furthermore, we explored the effects of allopregnanolone (by mouth), intra-CN microinjection of γ-aminobutyric acid type A receptor antagonist (bicuculline) or γ-aminobutyric acid type B receptor antagonist (phaclofen) plus allopregnanolone, and allopregnanolone synthesis inhibitor (medroxyprogesterone; subcutaneous) on ERK activation and CCI-induced behavioral hypersensitivity. At 7 days post-CCI, p-ERK levels in ipsilateral CN were significantly increased and reached a peak. PD98059 microinjection into the CN 1 day after CCI dose-dependently attenuated injury-induced behavioral hypersensitivity (withdrawal threshold [mean ± SD], 7.4 ± 1.1, 8.7 ± 1.0, and 10.3 ± 0.8 g for 2.0, 2.5, and 3.0 mM PD98059, respectively, at 7 days post-CCI; n = 6 for each dose). Double immunofluorescence showed that p-ERK was localized to both astrocytes and microglia. Allopregnanolone significantly diminished CN p-ERK levels, glial activation, proinflammatory cytokines, and behavioral hypersensitivity after CCI. Bicuculline, but not phaclofen, blocked all effects of allopregnanolone. Medroxyprogesterone treatment reduced endogenous CN allopregnanolone and exacerbated nerve injury-induced neuropathic pain. Median nerve injury-induced CN glial ERK activation modulated the development of behavioral hypersensitivity. Allopregnanolone attenuated

  2. Median nerve entrapment and ulnar nerve palsy following elbow dislocation in a child.

    PubMed

    Petratos, Dimitrios V; Stavropoulos, Nikolaos A; Morakis, Emmanouil A; Matsinos, George S

    2012-01-01

    This report presents a rare case of a child who presented with neglected intra-articular entrapment of the median nerve, ulnar nerve palsy, and intra-articular incarceration of the medial epicondyle following closed reduction of an elbow dislocation. In the present case, as in most other cases, the diagnosis and treatment were delayed. Careful initial and postreduction neurological examination, as well as careful interpretation of the plain radiographs, is necessary for early detection of any nerve complications and associated fractures of an elbow dislocation. The authors' opinion is that a child with an elbow dislocation, which is initially neurologically intact but advances to a median or ulnar nerve deficit after the reduction, must undergo early surgical exploration, especially when the dislocation is associated with a medial epicondyle fracture.

  3. Right Median Nerve Electrical Stimulation for Acute Traumatic Coma Patients.

    PubMed

    Lei, Jin; Wang, Lei; Gao, Guoyi; Cooper, Edwin; Jiang, Jiyao

    2015-10-15

    The right median nerve as a peripheral portal to the central nervous system can be electrically stimulated to help coma arousal after traumatic brain injury (TBI). The present study set out to examine the efficacy and safety of right median nerve electrical stimulation (RMNS) in a cohort of 437 comatose patients after severe TBI from August 2005 to December 2011. The patients were enrolled 2 weeks after their injury and assigned to the RMNS group (n=221) receiving electrical stimulation for 2 weeks or the control group (n = 216) treated by standard management according to the date of birth in the month. The baseline data were similar. After the 2-week treatment, the RMNS-treated patients demonstrated a more rapid increase of the mean Glasgow Coma Score, although statistical significance was not reached (8.43 ± 4.98 vs. 7.47 ± 5.37, p = 0.0532). The follow-up data at 6-month post-injury showed a significantly higher proportion of patients who regained consciousness (59.8% vs. 46.2%, p = 0.0073). There was a lower proportion of vegetative persons in the RMNS group than in the control group (17.6% vs. 22.0%, p = 0.0012). For persons regaining consciousness, the functional independence measurement (FIM) score was higher among the RMNS group patients (91.45 ± 8.65 vs. 76.23 ± 11.02, p < 0.001). There were no unique complications associated with the RMNS treatment. The current study, although with some limitations, showed that RMNS may serve as an easy, effective, and noninvasive technique to promote the recovery of traumatic coma in the early phase.

  4. Nociceptive and Histomorphometric Evaluation of Neural Mobilization in Experimental Injury of the Median Nerve

    PubMed Central

    Marcioli, Marieli Araujo Rossoni; Coradini, Josinéia Gresele; Kunz, Regina Inês; Ribeiro, Lucinéia de Fátima Chasko; Brancalhão, Rose Meire Costa; Bertolini, Gladson Ricardo Flor

    2013-01-01

    The carpal tunnel syndrome is the most common peripheral neuropathy in the upper limb, but its treatment with conservative therapies such as neural mobilization (NM) is still controversial. The aim of this study was to investigate the efficacy of the NM as treatment in a model of median nerve compression. 18 Wistar rats were subjected to compression of the median nerve in the right elbow proximal region. Were randomly divided into G1 (untreated), G2 (NM for 1 minute), and G3 (NM for 3 minutes). For treatment, the animals were anesthetized and the right forelimb received mobilization adapted to humans, on alternated days, from the 3rd to the 13th day postoperatively (PO), totaling six days of therapy. Nociception was assessed by withdrawal threshold, and after euthanasia histomorphometric analysis of the median nerve was performed. The nociceptive evaluation showed in G2 and G3 delay in return to baseline. Histomorphometric analysis showed no significant differences in the variables analyzed. It is concluded that the NM was not effective in reducing nociceptive sensation and did not alter the course of nerve regeneration. PMID:23935419

  5. Type I collagen nerve conduits for median nerve repairs in the forearm.

    PubMed

    Dienstknecht, Thomas; Klein, Silvan; Vykoukal, Jody; Gehmert, Sebastian; Koller, Michael; Gosau, Martin; Prantl, Lukas

    2013-06-01

    To evaluate patients with median nerve damage in the distal forearm treated with type 1 collagen nerve conduits. Nine patients with damage to the median nerve in the distal forearm underwent treatment with a type 1 collagen nerve conduit. The nerve gaps ranged between 1 and 2 cm. An independent observer reexamined patients after treatment at a minimal follow-up of 14 months and a mean follow-up of 21 months. Residual pain was evaluated using a visual analog scale. Functional outcome was quantified by assessing static 2-point discrimination, nerve conduction velocity relative to the uninjured limb, and Disabilities of the Arm, Shoulder, and Hand outcome measure scoring. We also recorded quality of life measures including patients' perceived satisfaction with the results and return to work latency. We observed no implant-related complications. Of 9 patients, 7 were free of pain, and the mean visual analog scale was 0.6. The mean Disabilities of the Arm, Shoulder, and Hand score was 6. The static 2-point discrimination was less than 6 mm in 3 patients, between 6 and 10 mm in 4 patients, and over 10 mm in 2 patients. Six patients reached a status of M4 or higher. Eight patients were satisfied with the procedure and would undergo surgery again. This study indicates that purified type 1 bovine collagen conduits are a practical and efficacious method for the repair of median nerves in the distal forearm. Therapeutic IV. Copyright © 2013 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  6. A histological analysis of human median and ulnar nerves following implantation of Utah slanted electrode arrays.

    PubMed

    Christensen, Michael B; Wark, Heather A C; Hutchinson, Douglas T

    2016-01-01

    For decades, epineurial electrodes have been used in clinical therapies involving the stimulation of peripheral nerves. However, next generation peripheral nerve interfaces for applications such as neuroprosthetics would benefit from an increased ability to selectively stimulate and record from nerve tissue. This increased selectivity may require the use of more invasive devices, such as the Utah Slanted Electrode Array (USEA). Previous research with USEAs has described the histological response to the implantation of these devices in cats and rats; however, no such data has been presented in humans. Therefore, we describe here the degree of penetration and foreign body reaction to USEAs after a four-week implantation period in human median and ulnar nerves. We found that current array designs penetrate a relatively small percentage of the available endoneurial tissue in these large nerves. When electrode tips were located within the endoneurial tissue, labels for axons and myelin were found in close proximity to electrodes. Consistent with other reports, we found activated macrophages attached to explanted devices, as well as within the tissue surrounding the implantation site. Despite this inflammatory response, devices were able to successfully record single- or multi-unit action potentials and elicit sensory percepts. However, modifying device design to allow for greater nerve penetration, as well as mitigating the inflammatory response to such devices, would likely increase device performance and should be investigated in future research. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Reliability of the nerve conduction monitor in repeated measures of median and ulnar nerve latencies

    SciTech Connect

    Washington, I.A.

    1994-05-06

    According to the Bureau of Labor Statistics, carpal tunnel syndrome (CTS), one of the most rapidly growing work-related injuries, cost American businesses up to $10 billion dollars in medical costs each year (1992). Because conservative therapy can be implemented and CTS is more reversible in it early stages, early detection will not only save industry unnecessary health care costs, but also prevent employees from experiencing debilitating pain and unnecessary surgery. In response to the growing number of cases of CTS, many companies have introduced screening tools to detect early stages of carpal tunnel syndrome. Neurotron Medical (New Jersey) has designed a portable nerve conduction monitor (Nervepace S-200) which measures motor and sensory nerve latencies. The slowing of these latencies is one diagnostic indicator of carpal tunnel syndrome. In this study, we determined the reliability of the Nervepace Monitor in measure ulnar and median nerve latencies during repeated testing. The testing was performed on 28 normal subjects between the ages of 20 and 35 who had no prior symptoms of CTS. They were tested at the same time each day for three consecutive days. Nerve latencies between different ethnic groups and genders were compared. Results show that there was no significant daily variation of the median motor and lunar sensory latencies or the median sensory latencies. No significant differences of latencies was observed among ethnic groups; however, a significant difference of latencies between male and female subjects was observed (p<0.05).

  8. A comparison of the accuracy of ulnar versus median nerve stimulation for neuromuscular monitoring.

    PubMed

    Lee, Hee Jong; Kim, Kyo Sang; Shim, Jae Chul; Yoon, Sung Wook

    2011-05-01

    Inexperienced anesthesiologists are frequently unclear as to whether to stimulate the ulnar or median nerve to monitor the adductor pollicis. The primary purpose of this study was to determine whether monitoring the adductor pollicis by positioning the stimulating electrodes over the median nerve is an acceptable alternative to applying electrodes over the ulnar nerve. In 20 patients anesthetized with propofol and remifentanil, one pair of stimulating electrodes was positioned over the ulnar nerve. A second pair was placed over the median nerve on the other hand. The acceleromyographic response was monitored on both hands. Rocuronium 0.6 mg/kg was administered. Single twitch (ST) and train-of-four (TOF) stimulations were applied alternatively to both sites. None of the patients showed a twitch response at either site after injection of rocuronium. There were no differences in the mean supramaximal threshold, mean initial TOF ratio, or mean initial ST ratio between the two sites. Bland-Altman analysis revealed a bias (limit of agreement) in the TOF and ST ratios over the median nerve of 7% (± 31%) and 26% (± 73%), respectively, as compared with the ulnar nerve. The median nerve TOF ratio was overestimated by 16.2%, as compared with that of the ulnar nerve value, and the median nerve ST ratio was overestimated by 72.9%, as compared to that of the ulnar nerve. The ulnar and median nerves cannot be used interchangeably for accurate neuromuscular monitoring.

  9. Transfer of the extensor indicis proprius branch of posterior interosseous nerve to reconstruct ulnar nerve and median nerve injured proximally: an anatomical study

    PubMed Central

    Wang, Pei-ji; Zhang, Yong; Zhao, Jia-ju; Zhou, Ju-pu; Zuo, Zhi-cheng; Wu, Bing-bing

    2017-01-01

    Proximal or middle lesions of the ulnar or median nerves are responsible for extensive loss of hand motor function. This occurs even when the most meticulous microsurgical techniques or nerve grafts are used. Previous studies had proposed that nerve transfer was more effective than nerve grafting for nerve repair. Our hypothesis is that transfer of the posterior interosseous nerve, which contains mainly motor fibers, to the ulnar or median nerve can innervate the intrinsic muscles of hands. The present study sought to investigate the feasibility of reconstruction of the deep branch of the ulnar nerve and the thenar branch of median nerve by transferring the extensor indicis proprius branch of the posterior interosseous nerve obtained from adult cadavers. The results suggested that the extensor indicis proprius branch of the posterior interosseous nerve had approximately similar diameters and number of fascicles and myelinated nerve fibers to those of the deep branch of ulnar nerve and the thenar branch of the median nerve. These confirm the feasibility of extensor indicis proprius branch of posterior interosseous nerve transfer for reconstruction of the deep branch of the ulnar nerve and the thenar branch of median nerve. This procedure could be a novel and effective method for the functional recovery of the intrinsic muscles of hands after ulnar nerve or median nerve injury. PMID:28250760

  10. Median nerve compression in the palm of the hand by an anomalously enlarged ulnar artery.

    PubMed

    Hankey, G J

    1988-06-01

    Median nerve compression in the carpal tunnel by a thrombosed persistent median artery and a large aberrant artery substituting for the radial artery has been described but there have been no reports of median nerve compression in the palm of the hand by an anomalously enlarged ulnar artery. A 46 year old man is described who presented with clinical and electrophysiological features consistent with a median neuropathy at the wrist but surgical exploration revealed median nerve compression in the palm of the hand by an anomalously enlarged palmar branch of the ulnar artery. This case highlights another treatable cause of median nerve compression and illustrates that symptoms suggestive of carpal tunnel syndrome may be produced by median nerve compression in the palm of the hand.

  11. Clinical and electrodiagnostic abnormalities of the median nerve in dental assistants.

    PubMed

    Greathouse, David G; Root, Tiffany M; Carrillo, Carla R; Jordan, Chelsea L; Pickens, Bryan B; Sutlive, Thomas G; Shaffer, Scott W; Moore, Josef H

    2009-09-01

    Descriptive. To determine the presence of clinical and electrodiagnostic abnormalities of the median and ulnar nerves in both upper extremities of dental assistants. A high prevalence of median neuropathies at, or distal to, the wrist have been reported in dentists and dental hygienists. But there is a paucity of literature on the incidence of abnormalities of the median or ulnar nerves in dental assistants. Thirty-five United States Army dental assistants (24 female, 11 male; age range, 18-41 years) volunteered for the study. Subjects completed a standardized history and physical examination. Nerve conduction status of the median and ulnar nerves of both upper extremities was obtained by performing motor, sensory, and F-wave (central) nerve conduction studies. All electrophysiological variables were normal for motor, sensory, and F-wave (central) values when compared to a chart of normal values. Based on comparison studies of median and ulnar motor latencies within the same hand, 9 subjects (26%) involving 14 hands (20%) were found to have electrodiagnostic abnormalities of the median nerve at, or distal to, the wrist. The other 26 dental assistants demonstrated normal comparison studies of the median and ulnar nerves in both upper extremities. In this descriptive study of 35 dental assistants, 9 subjects (26%) were found to have electrodiagnostic abnormalities of the median nerve at, or distal to, the wrist (when compared to the ulnar nerve of the same hand). Ulnar nerve electrophysiological function was within normal limits for all subjects examined.

  12. Three-dimensional reconstruction and visualization of the median nerve from serial tissue sections.

    PubMed

    Sun, Kuo; Zhang, Jian; Chen, Tongyi; Chen, Zhongwei; Chen, Zenggan; Li, Zhi; Li, Hua; Hu, Ping

    2009-01-01

    The purpose of this study was to definitively implement the three-dimensional visualization of sensory and motor fascicles in the human median nerve by means of acetylcholinesterase (AChe) histochemical staining and under the assistance of the computer technology. One fresh human median nerve was harvested from a male adult cadaver. The median nerve was fixed at a special holder. Then, the whole holder was embedded and rapidly frozen in the liquid nitrogen. The processed median nerve was then cut coronally every 100 microm at a 20 microm thickness along its long axis in a sliding freezing microtome. The total number of sections was 4,650 slices. All sections were stained with the AChe histochemical method. The stained sections were scanned and saved as Joint Photographic Experts Group files. These images with positively and negatively stained sections were acquired to an Intel dual Pentium computer. The Adobe Photoshop CS2 software was used to compare the reference points of images before and after staining. The two-dimensional intraneural microstructure database of median nerve was then acquired. A software of 3D nerve visualization system was developed. With the 3D nerve visualization system, the 3D visualization result of intraneural microstructure of median nerve was created. The findings may provide more accurate and detailed anatomic information for nerve repairs, specifically for the fascicular nerve repairs. The 3D nerve visualization technique may have potential for future studies of topography of peripheral nerve. (c) 2009 Wiley-Liss, Inc. Microsurgery, 2009.

  13. Assessment of Median Nerve Mobility by Ultrasound Dynamic Imaging for Diagnosing Carpal Tunnel Syndrome.

    PubMed

    Kuo, Tai-Tzung; Lee, Ming-Ru; Liao, Yin-Yin; Chen, Jiann-Perng; Hsu, Yen-Wei; Yeh, Chih-Kuang

    2016-01-01

    Carpal tunnel syndrome (CTS) is the most common peripheral neuropathy and is characterized by median nerve entrapment at the wrist and the resulting median nerve dysfunction. CTS is diagnosed clinically as the gold standard and confirmed with nerve conduction studies (NCS). Complementing NCS, ultrasound imaging could provide additional anatomical information on pathological and motion changes of the median nerve. The purpose of this study was to estimate the transverse sliding patterns of the median nerve during finger movements by analyzing ultrasound dynamic images to distinguish between normal subjects and CTS patients. Transverse ultrasound images were acquired, and a speckle-tracking algorithm was used to determine the lateral displacements of the median nerve in radial-ulnar plane in B-mode images utilizing the multilevel block-sum pyramid algorithm and averaging. All of the averaged lateral displacements at separate acquisition times within a single flexion-extension cycle were accumulated to obtain the cumulative lateral displacements, which were curve-fitted with a second-order polynomial function. The fitted curve was regarded as the transverse sliding pattern of the median nerve. The R2 value, curvature, and amplitude of the fitted curves were computed to evaluate the goodness, variation and maximum value of the fit, respectively. Box plots, the receiver operating characteristic (ROC) curve, and a fuzzy c-means clustering algorithm were utilized for statistical analysis. The transverse sliding of the median nerve during finger movements was greater and had a steeper fitted curve in the normal subjects than in the patients with mild or severe CTS. The temporal changes in transverse sliding of the median nerve within the carpal tunnel were found to be correlated with the presence of CTS and its severity. The representative transverse sliding patterns of the median nerve during finger movements were demonstrated to be useful for quantitatively estimating

  14. Assessment of Median Nerve Mobility by Ultrasound Dynamic Imaging for Diagnosing Carpal Tunnel Syndrome

    PubMed Central

    Kuo, Tai-Tzung; Lee, Ming-Ru; Liao, Yin-Yin; Chen, Jiann-Perng; Hsu, Yen-Wei; Yeh, Chih-Kuang

    2016-01-01

    Carpal tunnel syndrome (CTS) is the most common peripheral neuropathy and is characterized by median nerve entrapment at the wrist and the resulting median nerve dysfunction. CTS is diagnosed clinically as the gold standard and confirmed with nerve conduction studies (NCS). Complementing NCS, ultrasound imaging could provide additional anatomical information on pathological and motion changes of the median nerve. The purpose of this study was to estimate the transverse sliding patterns of the median nerve during finger movements by analyzing ultrasound dynamic images to distinguish between normal subjects and CTS patients. Transverse ultrasound images were acquired, and a speckle-tracking algorithm was used to determine the lateral displacements of the median nerve in radial-ulnar plane in B-mode images utilizing the multilevel block-sum pyramid algorithm and averaging. All of the averaged lateral displacements at separate acquisition times within a single flexion–extension cycle were accumulated to obtain the cumulative lateral displacements, which were curve-fitted with a second-order polynomial function. The fitted curve was regarded as the transverse sliding pattern of the median nerve. The R2 value, curvature, and amplitude of the fitted curves were computed to evaluate the goodness, variation and maximum value of the fit, respectively. Box plots, the receiver operating characteristic (ROC) curve, and a fuzzy c-means clustering algorithm were utilized for statistical analysis. The transverse sliding of the median nerve during finger movements was greater and had a steeper fitted curve in the normal subjects than in the patients with mild or severe CTS. The temporal changes in transverse sliding of the median nerve within the carpal tunnel were found to be correlated with the presence of CTS and its severity. The representative transverse sliding patterns of the median nerve during finger movements were demonstrated to be useful for quantitatively estimating

  15. Sensory distribution indicates severity of median nerve damage in carpal tunnel syndrome.

    PubMed

    Wilder-Smith, E P; Ng, E S; Chan, Y H; Therimadasamy, A K

    2008-07-01

    Sensory symptoms within the median nerve distribution are a primary clinical diagnostic criterion for the diagnosis of carpal tunnel syndrome (CTS). However, the distribution of the sensory symptoms in CTS varies from patient to patient. This study identifies the clinical and electrophysiological findings that correlate with the distribution of sensory symptoms in an Asian population with CTS. In a prospective study of 105 patients with electrophysiologically confirmed CTS, clinical and educational data were correlated with sensory symptom distribution. Median nerve distribution was strongly associated with more severe nerve conduction abnormality, male gender, and relief by movement. Patients with a complete median sensory distribution had more electrophysiological abnormality than those with an incomplete median distribution. Extra-median distribution was associated with the least nerve conduction abnormality. Educational qualification, age, symptom duration and body mass index were not associated with the pattern of sensory symptoms. In carpal tunnel syndrome, sensory symptom distribution is strongly dependant on the degree of electrophysiological median nerve damage. Median nerve sensory distribution is associated with severe nerve damage. This study provides clinicians with a simple clinical rule for assigning the degree of median nerve damage in patients with CTS based on sensory distribution patterns.

  16. Anatomic variations of the median nerve in the carpal tunnel: a brief review of the literature.

    PubMed

    Demircay, Emre; Civelek, Erdinc; Cansever, Tufan; Kabatas, Serdar; Yilmaz, Cem

    2011-01-01

    Carpal tunnel syndrome (CTS) is a common focal peripheral neuropathy. Increased pressure in the carpal tunnel results in median nerve compression and impaired nerve perfusion, leading to discomfort and paresthesia in the affected hand. Surgical division of the transverse carpal ligament is preferred in severe cases of CTS and should be considered when conservative measures fail. A through knowledge of the normal and variant anatomy of the median nerve in the wrist is fundamental in avoiding complications during carpal tunnel release. This paper aims to briefly review the anatomic variations of the median nerve in the carpal tunnel and its implications in carpal tunnel surgery.

  17. Bifid median nerve in carpal tunnel syndrome: do we need to know?

    PubMed

    Kasius, Kristel M; Claes, Franka; Meulstee, Jan; Verhagen, Wim Im

    2014-11-01

    We tested the hypothesis that a bifid median nerve predisposes to development of carpal tunnel syndrome (CTS) and investigated differences in electrophysiological findings and outcome. A total of 259 consecutive patients with clinically defined CTS were included and investigated clinically, electrophysiologically, and ultrasonographically. Fifty-four healthy asymptomatic volunteers were investigated ultrasonographically. The prevalence of bifid median nerves is equal in patients with CTS and controls. Electrophysiological and ultrasonographic abnormalities are more pronounced in patients with non-bifid median nerves. Some outcome data are better in patients with non-bifid median nerves, but others do not show significant differences. A bifid median nerve is not an independent risk factor for development of CTS. Some of our data suggest outcome after surgical decompression to be different, but others do not. The surgical technique in these patients may therefore have to be reevaluated. © 2014 Wiley Periodicals, Inc.

  18. Does measuring the median nerve at the carpal tunnel outlet improve ultrasound CTS diagnosis?

    PubMed

    Paliwal, P R; Therimadasamy, A K; Chan, Y C; Wilder-Smith, E P

    2014-04-15

    Nerve conduction is often regarded as more sensitive than ultrasonography (US) for diagnosing carpal tunnel syndrome (CTS). The diagnostic value of US derives from median nerve enlargement occurring at both ends of the carpal tunnel resulting in a dumbbell-like swelling from carpal tunnel pressure. An important reason for the inferior sensitivity of US may be because measurements are restricted to the carpal tunnel inlet. We investigate the value of including median nerve enlargement at the carpal tunnel outlet for diagnosing CTS. Retrospective cohort study of nerve conduction verified CTS, determining sensitivity, specificity, and positive and negative predictive values of carpal tunnel inlet and outlet median nerve cross sectional area as determined by US for the diagnosis of CTS. Nerve conduction graded CTS severity. 127 hands from 77 patients with CTS and 35 control healthy hands were assessed. US sensitivity for diagnosing CTS increased from 65% to 84% by including outlet enlargement of the median nerve. Specificity changed from 94% to 86%, positive predictive value from 98% to 96% and the negative predictive value from 43% to 60%. 25 hands out of the 127 from CTS patients showed enlargement restricted to the outlet and mainly occurred in moderate CTS. In our population, the use of carpal tunnel outlet median nerve enlargement in addition to inlet median nerve size increases sensitivity for diagnosing CTS by 19%. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Effects of computer keyboarding on ultrasonographic measures of the median nerve

    PubMed Central

    Toosi, KK; Impink, BG; Baker, NA; Boninger, ML

    2011-01-01

    Background Keyboarding is a highly repetitive daily task and has been linked to musculoskeletal disorders of the upper extremity. However, the effect of keyboarding on median nerve injuries is not well understood. The purpose of this study was to use ultrasonographic measurements to determine whether continuous keyboarding can cause acute changes in the median nerve. Methods Ultrasound images of the median nerve from twenty-one volunteers were captured at the levels of the pisiform and distal radius prior to and following a prolonged keyboarding task (i.e., one hour of continuous keyboarding). Images were analyzed by a blinded investigator to quantify the median nerve characteristics. Changes in the median nerve ultrasonographic measures as a result of continuous keyboarding task were evaluated. Results Cross-sectional areas at the pisiform level were significantly larger in both dominant (p=0.004) and non-dominant (p=0.001) hands following the keyboarding task. Swelling ratio was significantly greater in the dominant hand (p=0.020) after 60 minutes of keyboarding when compared to the baseline measures. Flattening ratios were not significantly different in either hand as a result of keyboarding. Conclusion We were able to detect an acute increase in the area of the median nerve following one hour of keyboarding with a computer keyboard. This suggests that keyboarding has an impact on the median nerve. Further studies are required to understand this relationship, which would provide insight into the pathophysiology of median neuropathies such as carpal tunnel syndrome. PMID:21739468

  20. Altered median nerve deformation and transverse displacement during wrist movement in patients with carpal tunnel syndrome.

    PubMed

    Wang, Yuexiang; Filius, Anika; Zhao, Chunfeng; Passe, Sandra M; Thoreson, Andrew R; An, Kai-Nan; Amadio, Peter C

    2014-04-01

    Carpal tunnel syndrome (CTS) is the most common peripheral nerve entrapment syndrome. Strong pinch or grip with wrist flexion has been considered a risk factor for CTS. Studying median nerve displacement during wrist movements may provide useful information about median nerve kinematic changes in patients with CTS. The purpose of this study was to evaluate the deformability and mobility of the median nerve in patients with CTS compared to healthy subjects. Dynamic ultrasound images were obtained in 20 affected wrists of 13 patients with CTS. Results were compared to complementary data obtained from both wrists of 10 healthy subjects reported in a previous study. Shape and position of initial and final median nerve were measured and analyzed for six defined wrist movements. The deformation ratios for each movement were defined as the median nerve area, perimeter, and circularity of the final position normalized by respective values assessed in the initial position. The median nerve displacement vector and magnitude were also calculated. The deformation ratio for circularity was significantly less in patients with CTS compared to healthy subjects during wrist flexion (P < .05). The mean vector of median nerve displacement during wrist flexion was significantly different between patients with CTS and healthy subjects (P < .05). The displacement magnitude of the median nerve was found to be less in patients with CTS compared to healthy subjects during most movements, with the exception of wrist extension with fingers extended. Patients with CTS differ from normal subjects with regard to mobility and deformability of the median nerve. Copyright © 2014 AUR. Published by Elsevier Inc. All rights reserved.

  1. Altered Median Nerve Deformation and Transverse Displacement during Wrist Movement in Patients with Carpal Tunnel Syndrome

    PubMed Central

    Wang, Yuexiang; Filius, Anika; Zhao, Chunfeng; Passe, Sandra M.; Thoreson, Andrew R.; An, Kai-Nan; Amadio, Peter C.

    2014-01-01

    Rationale and Objectives: Carpal tunnel syndrome (CTS) is the most common peripheral nerve entrapment syndrome. Strong pinch or grip with wrist flexion has been considered a risk factor for CTS. Studying median nerve displacement during wrist movements may provide useful information about median nerve kinematic changes in CTS patients. The purpose of this study was to evaluate the deformability and mobility of the median nerve in CTS patients compared to healthy subjects. Materials and Methods: Dynamic ultrasound images were obtained in 20 affected wrists of 13 patients with CTS. Results were compared to complementary data obtained from both wrists of 10 healthy subjects reported in a previous study. Initial and final median nerve shape and position were measured and analyzed for six defined wrist movements. The deformation ratios for each movement were defined as the median nerve area, perimeter and circularity of the final position normalized by respective values assessed in the initial position. The median nerve displacement vector and magnitude were also calculated. Results: The deformation ratio for circularity was significant less in CTS patients compared to healthy subjects during wrist flexion (P<0.05). The mean vector of median nerve displacement during wrist flexion was significantly different between CTS patients and healthy subjects (P<0.05). The displacement magnitude of the median nerve was found to be less in CTS patients compared to healthy subjects during most movements, with the exception of wrist extension with fingers extended. Conclusions: CTS Patients differ from normal subjects with regard to mobility and deformability of the median nerve. PMID:24594417

  2. Ultrasound measurements of the distance between acupuncture needle tip at P6 and the median nerve.

    PubMed

    Streitberger, Konrad; Eichenberger, Urs; Schneider, Antonius; Witte, Steffen; Greher, Manfred

    2007-06-01

    Pericard 6 (P6) is one of the most frequently used acupuncture points, especially in preventing nausea and vomiting. At this point, the median nerve is located very superficially. To investigate the distance between the needle tip and the median nerve during acupuncture at P6, we conducted a prospective observational ultrasound (US) imaging study. We tested the hypothesis that de qi (a sensation that is typical of acupuncture needling) is evoked when the needle comes into contact with the epineural tissue and thereby prevents nerve penetration. The outpatient pain clinic of the Medical University of Vienna, Austria. Fifty (50) patients receiving acupuncture treatment including P6 bilaterally. Patients were examined at both forearms using US (a 10-MHz linear transducer) after insertion of the needle at P6. The distance between the needle tip and the median nerve, the number of nerve contacts and nerve penetrations, as well as the number of successfully elicited de qi sensations were recorded. Complete data could be obtained from 97 cases. The mean distance from the needle tip to the nerve was 1.8 mm (standard deviation 2.2; range 0-11.3). Nerve contacts were recorded in 52 cases, in 14 of which the nerve was penetrated by the needle. De qi was elicited in 85 cases. We found no association between the number of nerve contacts and de qi. The 1-week follow-up showed no complications or neurologic problems. This is the first investigation demonstrating the relationship between acupuncture needle placement and adjacent neural structures using US technology. The rate of median nerve penetrations by the acupuncture needle at P6 was surprisingly high, but these seemed to carry no risk of neurologic sequelae. De qi at P6 does not depend on median nerve contact, nor does it prevent median nerve penetration.

  3. Cadaveric study of median nerve entrapment in the arm: report of two anatomical cases.

    PubMed

    Piyawinijwong, Sitha; Khampremsri, Nopamas; Ongsiriporn, Mathee; Roongruangchai, Jantima

    2011-11-01

    The authors report two anatomic cases of median nerve entrapment, which can be one of the causes of carpal tunnel syndrome. Both cases were soft tissue thickening on the distal arm. The first case was the thickening of brachial fascia that resembles the Struther's ligament. The second case was the thickening of the bicipital aponeurosis combined with the supernumerary biceps brachii. Both cases demonstrated the possible cause of median nerve entrapment at the arm, which mimicked the carpal tunnel syndrome that normally occurs at the wrist. The study reports other possibly sites of causes of median nerve entrapment that clinicians should be aware of the median nerve in the arm proximal to the wrist where the carpal tunnel syndrome normally occurs. These are other points of medina nerve entrapment that clinicians should aware.

  4. Modified Quad surgery significantly improves the median nerve conduction and functional outcomes in obstetric brachial plexus nerve injury

    PubMed Central

    2013-01-01

    Background Nerve conduction studies or somatosensory evoked potentials (SSEPs) have become an important tool in the investigation of peripheral nerve lesions, and is sensitive in detecting brachial plexus nerve injury, and other nerve injuries. To investigate whether the modified Quad surgical procedure improves nerve conductivity and functional outcomes in obstetric brachial plexus nerve injury (OBPI) patients. Methods All nerves were tested with direct functional electrical stimulation. A Prass probe was used to stimulate the nerves, and recording the response, the compound motor action potential (CMAP) in the muscle. SSEP monitoring was performed pre- and post modified Quad surgery, stimulating the median and ulnar nerves at the wrist, the radial nerve over the dorsum of the hand, recording the peripheral, cervical and cortical responses. All patients have had the modified Quad surgery (n = 19). The modified Quad surgery is a muscle release and transfer surgery with nerve decompressions. All patients were assessed preoperatively and postoperatively by evaluating video recordings of standardized movements, the modified Mallet scale to index active shoulder movements. Results The cervical responses were significantly lower in amplitude in the affected arm than the un-affected arm. The median nerve conduction was significantly improved from 8.04 to 9.26 (P < 0.022) post-operatively. The shoulder abduction was also significantly improved (pre-op 30° ± 23.3 to 143° ± 33.7, p < 0.0001), with a mean follow-up of 43 months after the modified Quad surgery in these patients. Conclusion Median nerve conduction, and shoulder abduction were significantly improved in OBPI children, who have undergone the modified Quad procedure with neuroplasty, internal microneurolysis and tetanic stimulation of the median nerve. PMID:23714699

  5. Modified Quad surgery significantly improves the median nerve conduction and functional outcomes in obstetric brachial plexus nerve injury.

    PubMed

    Nath, Rahul K; Kumar, Nirupuma; Somasundaram, Chandra

    2013-01-01

    Nerve conduction studies or somatosensory evoked potentials (SSEPs) have become an important tool in the investigation of peripheral nerve lesions, and is sensitive in detecting brachial plexus nerve injury, and other nerve injuries. To investigate whether the modified Quad surgical procedure improves nerve conductivity and functional outcomes in obstetric brachial plexus nerve injury (OBPI) patients. All nerves were tested with direct functional electrical stimulation. A Prass probe was used to stimulate the nerves, and recording the response, the compound motor action potential (CMAP) in the muscle. SSEP monitoring was performed pre- and post modified Quad surgery, stimulating the median and ulnar nerves at the wrist, the radial nerve over the dorsum of the hand, recording the peripheral, cervical and cortical responses. All patients have had the modified Quad surgery (n = 19). The modified Quad surgery is a muscle release and transfer surgery with nerve decompressions. All patients were assessed preoperatively and postoperatively by evaluating video recordings of standardized movements, the modified Mallet scale to index active shoulder movements. The cervical responses were significantly lower in amplitude in the affected arm than the un-affected arm. The median nerve conduction was significantly improved from 8.04 to 9.26 (P < 0.022) post-operatively. The shoulder abduction was also significantly improved (pre-op 30° ± 23.3 to 143° ± 33.7, p < 0.0001), with a mean follow-up of 43 months after the modified Quad surgery in these patients. Median nerve conduction, and shoulder abduction were significantly improved in OBPI children, who have undergone the modified Quad procedure with neuroplasty, internal microneurolysis and tetanic stimulation of the median nerve.

  6. Median nerve cross-sectional area and MRI diffusion characteristics: normative values at the carpal tunnel.

    PubMed

    Yao, Lawrence; Gai, Neville

    2009-04-01

    Enlargement of the median nerve is an objective potential imaging sign of carpal tunnel syndrome. Diffusion tensor MRI (DTI) may provide additional structural information that may prove useful in characterizing median neuropathy. This study further examines normal values for median nerve cross-sectional area (CSA), apparent diffusion coefficient (ADC), and fractional anisotropy (FA). Twenty-three wrists in 17 healthy volunteers underwent MRI of the wrist at 3 T. In 13 subjects, DTI was performed at a B value of 600 mm(2)/s. Median nerve CSA, ADC, and FA were analyzed at standardized anatomic levels. Mean (SD) median nerve CSA within the proximal carpal tunnel was 10.0 (3.4) mm(2). The mean (SD) FA of the median nerve was 0.71 (0.06) and 0.70 (0.13) proximal to and within the carpal tunnel, respectively. There was a significant difference between nerve CSA and ADC, but not FA, at the distal forearm and proximal carpal tunnel. Nerve CSA, ADC, and FA did not differ between men and women or between dominant and non-dominant wrists. Nerve CSA at the proximal carpal tunnel was positively correlated with subject age and body mass index. Our results suggest a 90% upper confidence limit for normal median nerve CSA of 14.4 mm(2) at the proximal carpal tunnel, higher than normal limits reported by many ultrasound studies. We observed a difference between the CSA and ADC, but not the FA, of the median nerve at the distal forearm and proximal carpal tunnel levels.

  7. Comparisons of outcomes from repair of median nerve and ulnar nerve defect with nerve graft and tubulization: a meta-analysis.

    PubMed

    Yang, Mei; Rawson, Jeremy L; Zhang, Elizabeth W; Arnold, Peter B; Lineaweaver, William; Zhang, Feng

    2011-10-01

    In this study, an updated meta-analysis of all published human studies was presented to evaluate the recovery of the median and the ulnar nerves in the forearm after defect repair by nerve conduit and autologous nerve graft. Up to June of 2010, search for English language articles was conducted to collect publications on the outcome of median or ulnar nerve defect repair. A total of 33 studies and 1531 cases were included in this study. Patient information was extracted from these publications and the postoperative outcome was analyzed using meta-analysis. There was no significant difference in the postoperative recovery between the median and the ulnar nerves (odds ratio = 0.98). Sensory nerves were found to achieve a more satisfactory recovery after nerve defect repair than motor nerves (P < 0.05). Median nerve can also achieve more satisfactory recovery in both sensory and motor function than ulnar nerve (P < 0.05). There was no statistical difference between tubulization and autologous nerve graft in repairing defects less than 5 cm. Based on the results of this study, a median nerve with sensory impairment was associated with improved postoperative prognosis, while an ulnar nerve with motor nerve damage was prone to a worse prognosis. Tubulization can be a good alternative in the reconstruction of small defects. © Thieme Medical Publishers.

  8. Median nerve fascicular anatomy as a basis for distal neural prostheses.

    PubMed

    Planitzer, Uwe; Steinke, Hanno; Meixensberger, Jürgen; Bechmann, Ingo; Hammer, Niels; Winkler, Dirk

    2014-05-01

    Functional electrical stimulation (FES) serves as a possible therapy to restore missing motor functions of peripheral nerves by means of cuff electrodes. FES is established for improving lower limb function. Transferring this method to the upper extremity is complex, due to a lack of anatomical data on the physiological configuration of nerve fascicles. Our study's aim was to provide an anatomical basis for FES of the median nerve in the distal forearm and hand. We investigated 21 distal median nerves from 12 body donors. The peripheral fascicles were traced back by removing the external and interfascicular epineurium and then assigned to 4 quadrants. A distinct motor and sensory distribution was observed. The fascicles innervating the thenar eminence and the first lumbrical muscle originated from the nerves' radial parts in 82%. The fascicle supplying the second lumbrical muscle originated from the ulnar side in 78%. No macroscopically visible plexus formation was observed for the distal median nerve in the forearm. The findings on the distribution of the motor branches of the median nerve and the missing plexus formation may likely serve as an anatomical basis for FES of the distal forearm. However, due to the considerable variability of the motor branches, cuff electrodes will need to be adapted individually in FES. Taking into account the sensory distribution of the median nerve, FES may also possibly be applied in the treatment of regional pain syndromes. Copyright © 2013 Elsevier GmbH. All rights reserved.

  9. [Paralysis of the median nerve due to a lipofibrohamartoma in the carpal tunnel].

    PubMed

    Biazzo, A; González Del Pino, J

    2013-01-01

    The lipofibrohamartoma is a rare entity of unknown origin that can affect any peripheral nerves, but mainly being found in the median nerve within the carpal tunnel. The lipofibrohamartoma is frequently associated with other conditions such as macrodactyly, the Proteus and Klippel-Trenaunay-Weber syndromes and multiple exostosis, among others. Two cases of lipofibrohamartoma in the carpal tunnel with associated median nerve palsy are described in the present article. They were treated by simple decompression of the median nerve by releasing the transverse carpal ligament and a palmaris longus tendon transfer to improve the thumb abduction (Camitz procedure). In one of the cases (a previously multi-operated median nerve entrapment at the carpal tunnel), a posterior interosseous skin flap was employed to improve the quality of the soft tissues on the anterior side of the wrist. A review of the literature is also presented on lipofibrohamartoma of the median nerve, covering articles from 1964 to 2010. The literature suggests that the most recommended treatment to manage this condition is simple release of the carpal tunnel, which should be associated with a tendon transfer when a median nerve palsy is noticed. Copyright © 2013 SECOT. Published by Elsevier Espana. All rights reserved.

  10. 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

  11. Protective coverage of the median nerve using fascial, fasciocutaneous or island flaps.

    PubMed

    Luchetti, R; Riccio, M; Papini Zorli, I; Fairplay, T

    2006-10-01

    The aim of the study is to present our experience with fascial or fasciocutaneous pedicle and island flaps in the treatment of recurrences of CTS with and without median nerve lesions. From 1987 to 2006 we have operated on 25 patients (17 women and 8 men, ages ranging from 38 to 76 years with a mean age of 55 years) due to a recurrence of CTS. All the patients required nerve coverage using a local or distant flap. There were 19 hypothenar fat flaps; two forearm radial artery flaps, a forearm ulnar artery flap, an ulnar fascial-fat flap and a posterior interosseous flap. Patients were clinically and instrumentally evaluated before the operation. Assessments of the evaluation parameters were classified in excellent, good, fair and poor according to clinical and return to work criteria. Patients were evaluated after a mean follow-up of 51 months (12 to 168 months). The pain evaluation showed an improvement passing from a mean value of 9 to 4. The best results were for those patients in whom the median nerve was undamaged (mean value of 1). Eleven patients obtained excellent results; good results were obtained in twelve cases; two patients demonstrated fair results due to partial median nerve injury. In these cases, a hypothenar fat flap and an ulnar fascial-fat flap were used, respectively. Protective coverage of the median nerve by using fascial or fasciocutaneous flaps after failure of CTR and/or unsuccessful re-operations is a good solution to furnish to the median nerve a gliding tissue to avoid adherences with the surrounding tissue of previous surgery. The protection of the nerve can reduce painful symptoms even if it does not permit a return to a painless condition. However, the clinical results in terms of median nerve functional recovery cannot be predicted: if the median nerve is damaged, protective coverage of it by flaps cannot give a favourable result in terms of recovery of both sensory and motor deficits.

  12. Cortical plasticity in patients with median nerve lesions studied with MEG.

    PubMed

    Fornander, Lotta; Brismar, Tom; Hansson, Thomas; Wikström, Heidi

    We have previously shown age- and time-dependent effects on brain activity in the primary somatosensory cortex (SI), in a functional magnetic resonance imaging (fMRI) study of patients with median nerve injury. Whereas fMRI measures the hemodynamic changes in response to increased neural activity, magnetoencephalography (MEG) offers a more concise way of examining the evoked response, with superior temporal resolution. We therefore wanted to combine these imaging techniques to gain additional knowledge of the plasticity processes in response to median nerve injury. Nine patients with median nerve trauma at the wrist were examined with MEG. The N1 and P1 responses at stimulation of the injured median nerve at the wrist were lower in amplitude compared to the healthy side (p < .04). Ulnar nerve stimulation of the injured hand resulted in larger N1 amplitude (p < .04). The amplitude and latency of the response did not correlate with the sensory discrimination ability. There was no correlation between N1 amplitude and size of cortical activation in fMRI. There was no significant difference in N1 latency between the injured and healthy median nerve. N1 latency correlated positively with age in both the median and ulnar nerve, and in both the injured and the healthy hand (p < .02 or p < .001). It is concluded that conduction failure in the injured segment of the median nerve decreases the amplitude of the MEG response. Disinhibition of neighboring cortical areas may explain the increased MEG response amplitude to ulnar nerve stimulation. This can be interpreted as a sign of brain plasticity.

  13. Reliability of measurement of the carpal tunnel and median nerve in asymptomatic subjects with ultrasound.

    PubMed

    Bueno-Gracia, Elena; Malo-Urriés, Miguel; Ruiz-de-Escudero-Zapico, Alazne; Rodríguez-Marco, Sonia; Jiménez-Del-Barrio, Sandra; Shacklock, Michael; Estébanez-de-Miguel, Elena; Tricás-Moreno, José Miguel

    2017-08-05

    Morphology of the carpal tunnel changes with varying wrist postures and compressive forces applied to the wrist. These changes may affect the morphology and pressure on the median nerve and could be used as part of the treatment of the carpal tunnel syndrome patients. Reliability of the ultrasonographic measurements of the median nerve has been widely studied. However, there is a lack of investigation regarding reliability of ultrasonographic measurements of the carpal tunnel. The purpose of this study was to assess intra-tester and inter-tester reliability of measurement of dimensions of the carpal tunnel and median nerve with ultrasound in asymptomatic volunteers. A cross-sectional methodological study. Aspects measured were mediolateral and anteroposterior diameters, flattening ratio, circularity, perimeter and cross-section area of the carpal tunnel and median nerve. Intra-tester reliability was excellent for the carpal tunnel (ICCs from 0.91 to 0.97) and for the median nerve (ICCs from 0.79 to 0.94) measurements. The flattening ratio of the median nerve showed good agreement (ICC = 0.68). Inter-tester reliability was excellent for the carpal tunnel measurements (ICCs from 0.76 to 0.95) and, for the cross sectional area, the perimeter and mediolateral diameter of the median nerve, the ICC values were 0.89, 0.84 and 0.81, respectively. In the context of this study, ultrasound was a reliable instrument for measuring carpal tunnel and median nerve dimensions in asymptomatic subjects. 1b. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Median nerve excursion in response to wrist movement after endoscopic and open carpal tunnel release.

    PubMed

    Tüzüner, Serdar; Inceoğlu, Salih; Bilen, F Erkal

    2008-09-01

    To compare the perioperative kinematic effects of endoscopic versus open carpal tunnel release on longitudinal excursion (gliding) and volar displacement (bowstringing) of the median nerve at the wrist region in patients with idiopathic primary carpal tunnel syndrome. Sixteen hands of 13 patients were randomly assigned into 2 groups (group 1, endoscopic; group 2, open carpal tunnel release). For the measurement of gliding and bowstringing of the median nerve, a metallic marker was used. Before and after the division of the transverse carpal ligament, longitudinal excursion and volar displacement of the median nerve were calculated based on fluoroscopic imaging for each wrist. Movement was analyzed for the measurement of the marker locations. The mean prerelease median nerve excursion during wrist range of motion was 20 mm (range, 10-28) in group 1 and 21 mm (range, 16-31 mm) in group 2. The mean postrelease median nerve excursion during wrist range of motion was 20 mm (range, 13-29) in group 1 and 18 mm (range, 8-26 mm) in group 2. There was no statistically significant difference in pre- and postrelease longitudinal excursion changes between the groups (p = .916 and p = .674, respectively). The mean prerelease volar displacement of the median nerve during wrist range of motion was 3 mm in group 1 and 4 mm in group 2; the postrelease mean values were 2 mm and 5 mm, respectively. There was no statistically significant difference between the groups with regard to pre- and postrelease volar displacement changes of the median nerve (p = .372 and p = .103, respectively). This study demonstrated that the endoscopic release and open carpal tunnel release produce similar perioperative effects on longitudinal and volar movements of the median nerve.

  15. Carpal tunnel syndrome due to lipofibromatous hamartoma of the median nerve.

    PubMed

    Afshar, Ahmadreza

    2010-01-01

    This report describes a rare case of secondary carpal tunnel syndrome due to a lipofibromatous hamartoma of the median nerve. Excision of the fibrofatty tissue between the nerve fascicles without risking damage to the fascicles was impossible. The transverse carpal ligament was incised and an epineurotomy was performed. Within six months, the 25-year-old female patient's symptoms were much improved.

  16. Variability of pudendal and median nerve sensory perception thresholds in healthy persons.

    PubMed

    Quaghebeur, Jörgen; Wyndaele, Jean-Jacques

    2015-04-01

    Normative current perception thresholds (CPTs) are used for the evaluation of sensory function in a variety of diseases. To evaluate the reproducibility of CPT measurements with sinusoidal current in healthy volunteers. Neuroselective CPT evaluations of the median and pudendal nerve in healthy volunteers were repeated with 1 week interval (T1 and T2). In the study group (N = 41) no difference between genders for age (MW-U: P = 0.91) and BMI (t-test: P = 0.18) were found. No significant difference between T1 and T2 was found (Paired t-test: all P-values > 0.05), although the intraclass correlation for each person was low. The variability of measures for the pudendal nerve was: ICC 2 kHz: 0.41; 250 Hz: 0.30; 5 Hz: 0.38, and for the median nerve respectively: 0.58; 0.46; 0.40. Normal CPTs were shown for the pudendal nerve: 2 kHz: 51%; 250 Hz: 76%; 5 Hz: 71%, and median nerve respectively: 78%; 98%; 80%. The pudendal nerve showed more deviating values compared to the median nerve. Both nerves showed deviating values. CPT values with sinusoidal current assessed with 1 week interval, showed a weak intraclass correlation. This finding limits the use of CPT values with this current for longitudinal studies. © 2014 Wiley Periodicals, Inc.

  17. Neuroma-in-continuity of the median nerve managed by nerve expansion and direct suture with vein conduit.

    PubMed

    Jeudy, J; Raimbeau, G; Rabarin, F; Fouque, P A; Saint-Cast, Y; Césari, B; Bigorre, N

    2014-06-01

    Autologous nerve grafting is the current standard for bridging large gaps in major sensory and motor nerves. It allows both function and pain improvement with predictable results. Clinical observations of nerve elongation caused by tumours have prompted experimental animal studies of induced gradual elongation of the nerve stump proximal to the gap. This technique allows direct suturing of the two nerve ends to bridge the gap. Here, we describe a case of neuroma-in-continuity of the median nerve managed by resection and direct suture after nerve elongation with a tissue expander. We are not aware of similar reported cases. Secondary repair 3 years after the initial injury improved the pain and hypersensitivity and restored a modest degree of protective sensory function (grade S1). Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  18. Normative Data for Median Nerve Conduction in Healthy Young Adults from Punjab, India.

    PubMed

    Singh, Manjinder; Gupta, Sharat; Singh, Kamal Dev; Kumar, Avnish

    2017-08-01

    Nerve conduction studies (NCSs) are essential for diagnosing various kinds of focal and diffuse neuropathies. Due to the paucity of local NCS data, electrodiagnostic laboratories in Punjab rely on values from Western and other Indian studies. This study was conducted to provide normative data for median nerve conduction parameters (motor and sensory) in Punjabi populace. A cross-sectional study was done on 290 participants (150 males and 140 females), aged 17-21 years, as per standardized protocol. The data were analyzed separately for both genders using SPSS version 20. It consisted of distal latencies and conduction velocities of motor and sensory divisions of median nerve. Student's unpaired t-test was used for statistical analysis. There was no effect of gender on any of the median nerve conduction parameters. Height and weight had nonsignificant negative and positive correlation, respectively (P > 0.05), with conduction velocity in both motor and sensory median nerves. For median motor nerve, the values of distal latency and conduction velocity in males were 2.9 ± 0.16 ms and 60.25 ± 2.99 m/s, respectively, whereas, in females, they were 2.6 ± 0.43 ms and 59.83 ± 2.82 m/s. Similarly, for median sensory nerve, the latency and velocity values in males were 2.8 ± 0.56 ms and 54.81 ± 3.70 m/s, whereas, in females, they were 2.4 ± 0.33 ms and 54.56 ± 3.65 m/s, respectively. The data in this study compared favorably with already existing data. It would help the local electrodiagnostic laboratories in assessing the median nerve abnormalities with greater accuracy in this population subset.

  19. Age-related differences in the quantitative echo texture of the median nerve.

    PubMed

    Li, Xiang; Li, Jia W; Ho, Anthony M-H; Karmakar, Manoj K

    2015-05-01

    Currently, there are no quantitative data on the echo texture of a peripheral nerve. This study was designed to objectively compare the differences in the echo texture of the median nerve in the young and the elderly. The median nerves of 10 healthy young volunteers (<30 years old; group Y) and 10 elderly patients undergoing lower limb surgery (>60 years old; group E) were scanned at the mid forearm by a standardized protocol. The echo texture of a normalized median nerve image was analyzed for the echo intensity and spatial distribution of pixels. Noise in the image was reduced by using a median filter, and thresholding was performed thereafter. In the resultant binary image, the cross-sectional area, echo intensity, white area index, and black area index of the median nerve were determined by computerized texture analysis. The mean cross-sectional area of the median nerve in group E was significantly smaller than that in group Y (P = .002). The mean echo intensity and white area index in group E were significantly higher than those in group Y (P= .002 and .012). The mean black area index in group E was correspondingly significantly lower than that in group Y (P = .012). In group Y, the mean white area index was significantly lower than the black area index (P = .006) but not in group E (P = .213). There are significant differences in the echo texture of the median nerve between the young and the elderly. These differences may be due to age-related changes in the relative proportion of neural fascicles and connective tissue within the nerve. © 2015 by the American Institute of Ultrasound in Medicine.

  20. Electrodiagnosis of Lesions of Median and Ulnar Nerve Hand Sensory Branches: A Case Series.

    PubMed

    Zanette, Giampietro; Lauriola, Matteo F; Tamburin, Stefano

    2016-10-01

    The authors have recently tested a new electrodiagnostic technique for palmar proper digital nerves sensory nerve action potentials in normal controls. Here the authors explored whether it may offer additional information in comparison to mixed nerve wrist stimulation in a series of patients. The authors recorded palmar proper digital nerves sensory nerve action potential to selective antidromic webspace stimulation in a group of 19 patients with suspected lesions of median and ulnar nerve hand sensory branches. Coexistent carpal tunnel syndrome was present in 11 patients. The webspace stimulation technique offered additional information in 89% patients when compared with mixed nerve wrist stimulation. Webspace stimulation was informative even when carpal tunnel syndrome coexisted with damage to hand sensory branches and biased the interpretation of conventional wrist nerve conduction study. Webspace PaPDN stimulation is feasible in patients with lesion of median and ulnar nerve hand sensory branches and offer additional information in comparison with wrist-mixed nerve conduction study, also in patients with coexisting carpal tunnel syndrome.

  1. Platelet-rich plasma limits the nerve injury caused by 10% dextrose in the rabbit median nerve.

    PubMed

    Park, Gi-Young; Kwon, Dong Rak

    2014-01-01

    We evaluated the effect of platelet-rich plasma (PRP) injection in a rabbit model of dextrose-induced median nerve injury. New Zealand white rabbits (n = 15) were divided randomly into 3 groups. Three different regimens (group 1: 0.1 ml saline; group 2: 10% dextrose with PRP; group 3: 10% dextrose with saline) were injected within the carpal tunnel. Electrophysiological and histological findings were evaluated 12 weeks after the injection. The mean median motor latency in group 3 was significantly longer than that in groups 1 and 2. The cross-sectional area of the median nerve and subsynovial connective tissue thickness in group 3 were significantly larger than those in groups 1 and 2. PRP injection may be effective in controlling median nerve injury, as demonstrated by improvement in electrophysiological and histological findings 12 weeks after dextrose injection. Copyright © 2013 Wiley Periodicals, Inc.

  2. Verification of the median-to-ulnar and ulnar-to-median nerve motor fiber anastomosis in the forearm: an electrophysiological study.

    PubMed

    Amoiridis, Georgios; Vlachonikolis, Ioannis G

    2003-01-01

    To estimate the real occurrence of the motor median-to-ulnar nerve anastomosis in the proximal forearm (Martin-Gruber anastomosis, MGA), as its frequency varies between 6 and 44% in the literature and to investigate the incidence of the ulnar-to-median nerve anastomosis in the distal forearm. Compound muscle action potentials (CMAP) recorded over thenar, hypothenar, and first dorsal interosseus muscle on median or ulnar nerve stimulation at wrist and elbow and collision blocks of the median and ulnar nerve were compared in a group of 50 healthy volunteers. Particular precautions were undertaken in order to avoid false positive results due to stimulus spread to the neighboring nerve. Cases of uncertain MGA were classified as either MGA or non-MGA on the basis of posterior probabilities estimated by discriminant analysis. The estimated frequency of MGA was 54% using the potential comparison method and 46% using the collision technique. An ulnar-to-median nerve anastomosis was not found in any subject. While the MGA is very common, the ulnar-to-median nerve anastomosis is a rarity. Standard nerve conduction studies of the median nerve with CMAP recordings solely over thenar will detect less than 14% of MGA cases.

  3. Effect of pioglitazone on nerve conduction velocity of the median nerve in the carpal tunnel in type 2 diabetes patients.

    PubMed

    Chatterjee, Sudip; Sanyal, Debmalya; Das Choudhury, Sourav; Bandyopadhyay, Mili; Chakraborty, Suraj; Mukherjee, Arabinda

    2016-11-15

    To evaluate the impact of pioglitazone pharmacotherapy in median nerve electrophysiology in the carpal tunnel among type 2 diabetes patients. The study was executed in patients with type 2 diabetes, treated with oral drugs, categorized under pioglitazone or non-pioglitazone group (14 in each group), and who received electrophysiological evaluation by nerve conduction velocity at baseline and 3 mo. At 3 mo, pioglitazone-category had inferior amplitude in sensory median nerve [8.5 interquartile range (IQR) = 6.5 to 11.5) vs non-pioglitazone 14.5 (IQR 10.5 to 18.75)] (P = 0.002). Non-pioglitazone category displayed amelioration in amplitude in the sensory median nerve [baseline 13 (IQR = 9 to 16.25) vs 3 mo 8.5 (IQR = 6.5 to 11.5)] (P = 0.01) and amplitude in motor median nerve [baseline 9 (IQR = 4.75 to 11) vs 3 mo 6.75 (IQR = 4.75 to 10.25)] (P = 0.049); and deterioration of terminal latency of in motor ulnar nerve [baseline 2.07 (IQR = 1.92 to 2.25) vs 3 mo 2.16 (IQR = 1.97 to 2.325)] (P = 0.043). There was amelioration of terminal latency in sensory ulnar nerve [baseline 2.45 (IQR = 2.315 to 2.88) vs 3 mo 2.37 (IQR = 2.275 to 2.445) for pioglitazone group (P = 0.038). Treatment with pioglitazone accentuates probability of compressive neuropathy. In spite of comparable glycemic control over 3 mo, patients treated with pioglitazone showed superior electrophysiological parameters for the ulnar nerve. Pioglitazone has favourable outcome in nerve electrophysiology which was repealed when the nerve was subjected to compressive neuropathy.

  4. Effect of pioglitazone on nerve conduction velocity of the median nerve in the carpal tunnel in type 2 diabetes patients

    PubMed Central

    Chatterjee, Sudip; Sanyal, Debmalya; Das Choudhury, Sourav; Bandyopadhyay, Mili; Chakraborty, Suraj; Mukherjee, Arabinda

    2016-01-01

    AIM To evaluate the impact of pioglitazone pharmacotherapy in median nerve electrophysiology in the carpal tunnel among type 2 diabetes patients. METHODS The study was executed in patients with type 2 diabetes, treated with oral drugs, categorized under pioglitazone or non-pioglitazone group (14 in each group), and who received electrophysiological evaluation by nerve conduction velocity at baseline and 3 mo. RESULTS At 3 mo, pioglitazone-category had inferior amplitude in sensory median nerve [8.5 interquartile range (IQR) = 6.5 to 11.5) vs non-pioglitazone 14.5 (IQR 10.5 to 18.75)] (P = 0.002). Non-pioglitazone category displayed amelioration in amplitude in the sensory median nerve [baseline 13 (IQR = 9 to 16.25) vs 3 mo 8.5 (IQR = 6.5 to 11.5)] (P = 0.01) and amplitude in motor median nerve [baseline 9 (IQR = 4.75 to 11) vs 3 mo 6.75 (IQR = 4.75 to 10.25)] (P = 0.049); and deterioration of terminal latency of in motor ulnar nerve [baseline 2.07 (IQR = 1.92 to 2.25) vs 3 mo 2.16 (IQR = 1.97 to 2.325)] (P = 0.043). There was amelioration of terminal latency in sensory ulnar nerve [baseline 2.45 (IQR = 2.315 to 2.88) vs 3 mo 2.37 (IQR = 2.275 to 2.445) for pioglitazone group (P = 0.038). CONCLUSION Treatment with pioglitazone accentuates probability of compressive neuropathy. In spite of comparable glycemic control over 3 mo, patients treated with pioglitazone showed superior electrophysiological parameters for the ulnar nerve. Pioglitazone has favourable outcome in nerve electrophysiology which was repealed when the nerve was subjected to compressive neuropathy. PMID:27895823

  5. Sleep Deprivation Aggravates Median Nerve Injury-Induced Neuropathic Pain and Enhances Microglial Activation by Suppressing Melatonin Secretion

    PubMed Central

    Huang, Chun-Ta; Chiang, Rayleigh Ping-Ying; Chen, Chih-Li; Tsai, Yi-Ju

    2014-01-01

    Study Objectives: Sleep deprivation is common in patients with neuropathic pain, but the effect of sleep deprivation on pathological pain remains uncertain. This study investigated whether sleep deprivation aggravates neuropathic symptoms and enhances microglial activation in the cuneate nucleus (CN) in a median nerve chronic constriction injury (CCI) model. Also, we assessed if melatonin supplements during the sleep deprived period attenuates these effects. Design: Rats were subjected to sleep deprivation for 3 days by the disc-on-water method either before or after CCI. In the melatonin treatment group, CCI rats received melatonin supplements at doses of 37.5, 75, 150, or 300 mg/kg during sleep deprivation. Melatonin was administered at 23:00 once a day. Participants: Male Sprague-Dawley rats, weighing 180-250 g (n = 190), were used. Measurements: Seven days after CCI, behavioral testing was conducted, and immunohistochemistry, immunoblotting, and enzyme-linked immunosorbent assay were used for qualitative and quantitative analyses of microglial activation and measurements of proinflammatory cytokines. Results: In rats who underwent post-CCI sleep deprivation, microglia were more profoundly activated and neuropathic pain was worse than those receiving pre-CCI sleep deprivation. During the sleep deprived period, serum melatonin levels were low over the 24-h period. Administration of melatonin to CCI rats with sleep deprivation significantly attenuated activation of microglia and development of neuropathic pain, and markedly decreased concentrations of proinflammatory cytokines. Conclusions: Sleep deprivation makes rats more vulnerable to nerve injury-induced neuropathic pain, probably because of associated lower melatonin levels. Melatonin supplements to restore a circadian variation in melatonin concentrations during the sleep deprived period could alleviate nerve injury-induced behavioral hypersensitivity. Citation: Huang CT, Chiang RP, Chen CL, Tsai YJ. Sleep

  6. Cerebral changes after injury to the median nerve: a long-term follow up.

    PubMed

    Rosén, Birgitta; Chemnitz, Anette; Weibull, Andreas; Andersson, Gert; Dahlin, Lars B; Björkman, Anders

    2012-04-01

    Injury to the peripheral nerves in the upper extremity results in changes in the nerve, and at multiple sites throughout the central nervous system (CNS). We studied the long-term effects of an injury to the median nerve in the forearm with a focus on changes in the CNS. Four patients with isolated injuries of the median nerve in their 20s were examined a mean of 14 years after the injury. Cortical activation was monitored during tactile stimulation of the fingers of the injured and healthy hand using functional magnetic resonance imaging at 3 Tesla. The neurophysiological state and clinical outcome were also examined. Activation in the primary somatosensory cortex was substantially larger during tactile stimulation of the injured hand than with stimulation of the uninjured hand. We also saw a redistribution of hemispheric dominance. Stimulation of the injured median nerve resulted in a substantially increased dominance of the contralateral hemisphere. However, stimulation of the healthy ulnar nerve resulted in a decreased dominance of the contralateral hemisphere. Neurophysiology showed low sensory amplitudes, velocity, and increased motor latency in the injured nerve. Clinically there were abnormalities predominately in the sensory domain. However, there was an overall improved mean result compared with a five year follow-up in the same subjects. The cortical changes could be the result of cortical reorganisation after a changed afferent signal pattern from the injured nerve. Even though the clinical function improved over time it did not return to normal, and neither did the cortical response.

  7. Anatomic variations in the palmar cutaneous branch of the median nerve among adults in Lagos, Nigeria

    PubMed Central

    Mofikoya, Bolaji O; Ugburo, Andrew O

    2012-01-01

    Dysesthesias due to palmar cutaneous branch of median nerve injuries infrequently follow carpal tunnel release surgeries. Objective: To determine the course of palmar cutaneous branch of the median nerve in wrist of adult Nigerians, identify the common variations, determine its relations to the palmaris longus (PL) in the region of the distal wrist crease. And on these basis, suggest a safe incision for carpal tunnel surgery in Nigerians. Materials and Methods: Detailed anatomic dissection of the palmar cutaneous branch of the median nerve was carried out with the aid of a loupe magnification on 40 Nigerian cadaver wrists. The origin, course in the distal forearm, wrist and proximal palm was traced. Measurements of the distances between the radial and ulnar branches of the nerve and the PL were made. The distance between origin of the nerve and the distal wrist crease was measured as well. The common branching pattern of the nerve was noted. Results: The palmar cutaneous branch of the median nerve was present in all dissected wrists. The mean distance of the radial branch to PL was 0.81 cm (SD ± 0.3 cm), while the ulnar branch was 0.3 cm (SD ± 0.1 cm). from same structure. The mean distance from the origin to the distal wrist crease is 4.5 cm (SD ± 2.1 cm). We noted the terminal distal branching pattern of the nerve to be highly variable. Conclusion: The Palmar cutaneous branch of the median nerve is safe with an incision made at least 0.5 cm ulnar to the PL in carpal tunnel surgeries in Nigerians. PMID:24027400

  8. Memory Effect of the Median Nerve: Can Ultrasound Reliably Depict Carpal Tunnel Release Success?

    PubMed

    Steinkohl, Fabian; Gruber, Leonhard; Gruber, Hannes; Löscher, Wolfgang; Glodny, Bernhard; Pülzl, Petra; Baur, Eva-Maria; Loizides, Alexander

    2017-01-01

    Purpose To evaluate whether ultrasound findings of the median nerve cross-section area (CSA) and wrist-to-forearm ratio (WFR) correlate with neurophysiological and patient-reported outcome after surgery for carpal tunnel syndrome (CTS). Materials and Methods Subjective pain, CSA, WFR, postoperative scar tissue formation and nerve conduction velocity in 21 hands of 20 patients with clinically confirmed CTS were examined before and after carpal tunnel release surgery. Group differences were compared via a 2-sided ratio paired t-test or one-way ANOVA, and correlations were calculated using a linear regression model. Results There were no significant pre- and postoperative changes of the CSA of the median nerve (p = 0.293, 95 % CI 0.826 - 1.063) or WFR (p = 0.230, 95 % CI 0.757 - 1.074). The nerve conduction velocity (p < 0.0001, 95 % CI 0.753 - 0.886) and subjective pain during rest (p = 0.001, 95 % CI 1.615 - 5.797) and exercise (p = 0.008, 95 % CI 0.760 - 4.888) improved significantly, though. There was no correlation between changes in the median nerve CSA and nerve conduction velocity (p = 0.357, r = 0.217, R2 = 0.047) or reported pain intensity (p = 0.441, r = 0.200, R2 = 0.040). Conclusion Contrary to common assumptions, there is no significant reduction of the CSA of the median nerve after successful carpal tunnel release. Morphologic median nerve changes may persist for a longer period regardless of successful surgery and clinical improvement. Accordingly, ultrasound appears unsuitable as the primary means of assessing surgical success due to this "memory effect". Key Points · CSA of the median nerve does not change significantly after successful carpal tunnel release.. · Morphologic median nerve alterations may persist regardless of functional outcome ("memory effect").. · Therefore, ultrasound imaging is not ideally suited to assess the outcome after carpal tunnel release

  9. Median nerve imaging using high-resolution ultrasound in healthy subjects.

    PubMed

    Azman, Drazen; Bosnjak, Jelena; Strineka, Maja; Béné, Raphael; Budisić, Mislav; Lovrencić-Huzjan, Arijana; Demarin, Vida

    2009-09-01

    Although electroneuro- and electromyography are still the leading diagnostic methods for investigation of peripheral nerve function, they do not provide information on their morphology. This study was conducted to evaluate the suitability of ultrasonography in visualization of median nerve in healthy volunteers. Twenty-five asymptomatic volunteers (17 women and 8 men), age range 21-47 years, participated in the study. Body height was measured and handedness ascertained, as well as average time spent daily working on a computer. The device used was Aloka Prosound Alpha10 Premier with a 13-MHz probe, using custom preset for musculoskeletal sonography. The following dimensions of median nerve at the pisiform bone level were measured bilaterally: cross-sectional area (CSA), circumference, and longer and shorter diameter. Using the latter values, the flattening ratio (FR) was calculated. Median nerve and the surrounding soft tissue structures were easily depicted in all study subjects. The mean median nerve CSA was 9.70 mm2 (range 5-15 mm2, SD 2.25 mm2), mean FR (longer/shorter diameter) 4.04 (range 2.16-6.08), and median height 172.72 cm. Only one subject was left-handed. The mean time spent daily working on a computer (overall mean of 3.2 h/day) did not correlate with either CSA or FR for the dominant hand. In four subjects, an aberrant artery accompanying median nerve was visualized. High-resolution sonographic imaging is a fast and noninvasive method for assessment of various morphological properties of median nerve and can be used to enhance diagnostic efficiency.

  10. Extensor indicis proprius opponensplasty for isolated traumatic low median nerve palsy: A case series.

    PubMed

    Al-Qattan, Mohammad M

    2012-01-01

    The standard opponensplasty for isolated low median nerve palsy in nonleprosy patients uses the flexor digitorum superficialis of the ring finger. To report the results of extensor indicis proprius (EIP) opponensplasty in 15 consecutive nonleprosy patients with isolated traumatic low median nerve palsy. A retrospective study of the author's cases of EIP opponensplasty for isolated traumatic median nerve palsy over the past 15 years was conducted. The author used the EIP to restore thumb opposition in all cases of isolated median nerve palsies when the following conditions were present: protective sensibility in the median nerve distribution; normal power of EIP; supple hands; and full passive range of opposition with no contracture of the first web space. There were a total of 15 patients with a mean age of 30 years (range 20 to 45 years). They all had traumatic isolated low median nerve palsy with recovery of at least protective sensation and no recovery of opposition. The tendon was harvested just proximal to the extensor expansion, the flexor carpi ulnaris was used as a pulley and the insertion was to the tendon of abductor pollicis brevis. There were no postoperative complications or extension lag of the donor finger. Using previously published criteria, 12 patients experienced excellent results while the remaining three had a good result. In nonleprosy patients with isolated traumatic low median nerve palsy, the results of this transfer are consistent and there is no need to harvest the EIP tendon distal to the extensor expansion because a single insertion to the abductor pollicis brevis is sufficient.

  11. Day-to-day variability of median nerve location within the carpal tunnel.

    PubMed

    Goetz, Jessica E; Thedens, Daniel R; Kunze, Nicole M; Lawler, Ericka A; Brown, Thomas D

    2010-08-01

    Carpal tunnel syndrome is a commonly encountered entrapment disorder resulting from mechanical insult to the median nerve. Magnetic resonance imaging (MRI)-based investigations have documented typical locations of the median nerve within the carpal tunnel; however, it is unclear whether those locations are consistent within an individual on different days. To determine the day-to-day variability of nerve location, 3.0T MRI scans were acquired from six normal volunteers over multiple sessions on three different days. Half of the scans were acquired with the wrist in neutral flexion and the fingers extended, and the other half were acquired with the wrist in 35 degrees of flexion and the fingers flexed. Prior to half of the scans (in both poses), subjects performed a preconditioning routine consisting of specified hand activities and several repetitions of wrist flexion/extension. The shape, orientation, location, and location radius of variability of the median nerve and three selected flexor tendons were determined for each subject and compared between days. Two of the six subjects had substantial variability in nerve location when the wrist was in neutral, and four of the subjects had high variability in nerve position when the wrist was flexed. Nerve variability was typically larger than tendon variability. The preconditioning routine did not decrease nerve or tendon location variability in either the neutral or the flexed wrist positions. The high mobility and potential for large variability in median nerve location within the carpal tunnel needs to be borne in mind when interpreting MR images of nerve location. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  12. Day-to-Day Variability of Median Nerve Location within the Carpal Tunnel

    PubMed Central

    Goetz, Jessica E.; Thedens, Daniel R.; Kunze, Nicole M.; Lawler, Ericka A.; Brown, Thomas D.

    2010-01-01

    Background Carpal tunnel syndrome is a commonly encountered entrapment disorder resulting from mechanical insult to the median nerve. MRI-based investigations have documented typical locations of the median nerve within the carpal tunnel; however, it is unclear whether those locations are consistent within an individual on different days. Methods To determine the day-to-day variability of nerve location, 3.0T MRI scans were acquired from six normal volunteers over multiple sessions on three different days. Half of the scans were acquired with the wrist in neutral flexion and the fingers extended, and the other half were acquired with the wrist in 35 degrees of flexion and the fingers flexed. Prior to half of the scans (in both poses), subjects performed a preconditioning routine consisting of specified hand activities and several repetitions of wrist flexion/extension. The shape, orientation, location, and location radius of variability of the median nerve and three selected flexor tendons were determined for each subject and compared between days. Findings Two of the six subjects had substantial variability in nerve location when the wrist was in neutral, and four of the subjects had high variability in nerve position when the wrist was flexed. Nerve variability was typically larger than tendon variability. The preconditioning routine did not decrease nerve or tendon location variability in either the neutral or the flexed wrist positions. Interpretation The high mobility and potential for large variability in median nerve location within the carpal tunnel needs to be borne in mind when interpreting MR images of nerve location. PMID:20605292

  13. Analyzing cost-effectiveness of ulnar and median nerve transfers to regain forearm flexion.

    PubMed

    Wali, Arvin R; Park, Charlie C; Brown, Justin M; Mandeville, Ross

    2017-03-01

    OBJECTIVE Peripheral nerve transfers to regain elbow flexion via the ulnar nerve (Oberlin nerve transfer) and median nerves are surgical options that benefit patients. Prior studies have assessed the comparative effectiveness of ulnar and median nerve transfers for upper trunk brachial plexus injury, yet no study has examined the cost-effectiveness of this surgery to improve quality-adjusted life years (QALYs). The authors present a cost-effectiveness model of the Oberlin nerve transfer and median nerve transfer to restore elbow flexion in the adult population with upper brachial plexus injury. METHODS Using a Markov model, the authors simulated ulnar and median nerve transfers and conservative measures in terms of neurological recovery and improvements in quality of life (QOL) for patients with upper brachial plexus injury. Transition probabilities were collected from previous studies that assessed the surgical efficacy of ulnar and median nerve transfers, complication rates associated with comparable surgical interventions, and the natural history of conservative measures. Incremental cost-effectiveness ratios (ICERs), defined as cost in dollars per QALY, were calculated. Incremental cost-effectiveness ratios less than $50,000/QALY were considered cost-effective. One-way and 2-way sensitivity analyses were used to assess parameter uncertainty. Probabilistic sampling was used to assess ranges of outcomes across 100,000 trials. RESULTS The authors' base-case model demonstrated that ulnar and median nerve transfers, with an estimated cost of $5066.19, improved effectiveness by 0.79 QALY over a lifetime compared with conservative management. Without modeling the indirect cost due to loss of income over lifetime associated with elbow function loss, surgical treatment had an ICER of $6453.41/QALY gained. Factoring in the loss of income as indirect cost, surgical treatment had an ICER of -$96,755.42/QALY gained, demonstrating an overall lifetime cost savings due to

  14. Morphological and positional changes of the carpal arch and median nerve during wrist compression.

    PubMed

    Marquardt, Tamara L; Gabra, Joseph N; Li, Zong-Ming

    2015-03-01

    The carpal tunnel is a fibro-osseous structure containing the median nerve and flexor tendons. Its cross-sectional area has been shown to increase during compressive force application to the carpal bones in modeling and in vitro studies. The purpose of this study was to investigate the morphological and positional changes of the carpal arch and median nerve while in vivo compressive force was applied in the radioulnar direction across the wrist. Ultrasound images of the carpal tunnel and its contents were captured for 11 healthy, female volunteers at the distal tunnel level prior to force application and during force application of 10 and 20N. With applied force, the carpal arch width significantly decreased, while the carpal arch height and area significantly increased (P<0.001). The median nerve shape became more rounded as the compressive force magnitude increased, reflected by decreases in the nerve's flattening ratio and increases in its circularity (P<0.001). The applied force also resulted in nerve displacement in the radial-volar direction. This study demonstrates that noninvasively applying radioulnar compressive force across the wrist may potentially provide relief of median nerve compression to patients suffering from carpal tunnel syndrome. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Lipofibromatous Hamartoma of the Median Nerve in Association with or without Macrodactyly.

    PubMed

    Kini, Jyoti R; Kini, Hema; Rau, Aarathi; Kamath, Jagannath; Kini, Anand

    2014-11-05

    Lipofibromatous hamartoma is a rare tumour-like condition involving the peripheral nerves, particularly the median nerve. It commonly affects the volar aspect of the hands, wrists and forearms of young adults. Most patients present either early with macrodactyly or later with a forearm mass lesion or symptoms consistent with compressive neuropathy of the involved nerve. The clinical and histomorphological findings of five patients with lipofibromatous hamartoma of the median nerve are analysed. The presentation, pathological features and differential diagnosis of neural lipofibromas are discussed along with a brief review of the literature. Of the five cases of lipofibromatous hamartoma, all were seen to involve the median nerve, occurring in four women and one man. Three of these cases had associated macrodactyly which was congenital in two and was seen from childhood in one. Microscopic examination showed fibrofatty tissue surrounding and infiltrating along the epineurium and perineurium. The nerve bundles were splayed apart by the infiltrating adipose tissue. Neural fibrolipomatous hamartoma is a benign condition. Most respond to conservative management with surgical exploration, biopsy and carpal tunnel release to decompress the nerve. Correct diagnosis of this uncommon lesion is important as surgical excision of the lesion may lead to loss of neurological function.

  16. Biomechanics of the Median Nerve During Stretching as Assessed by Ultrasonography.

    PubMed

    Martínez-Payá, Jacinto Javier; Ríos-Díaz, José; Del Baño-Aledo, María Elena; García-Martínez, David; de Groot-Ferrando, Ana; Meroño-Gallut, Javier

    2015-12-01

    The objective of this observational cross-sectional study was to investigate the normal motion of the median nerve when stretched during a neurodynamic exercise. In recent years, ultrasonography has been increasingly accepted as an imaging technique for examining peripheral nerves in vivo, offering a reliable and noninvasive method for a precise evaluation of nerve movement. Transverse motion of the median nerve in the arm during a neurodynamic test was measured. A volunteer sample of 22 healthy subjects (11 women) participated in the study. Nerve displacement and deformation were assessed by dynamic ultrasonography. Excellent interobserver agreement was obtained, with kappa coefficient of .7-.8. Ultrasonography showed no lateral motion during wrist extension in 68% of nerves, while 73% moved dorsally, with statistically significant differences between sexes (ORlat = 6.3; 95% CI = 1.4-27.7 and ORdor = 8.3; 95% CI = 1.6-44.6). The cross-sectional area was significantly greater in men (3.6 mm2). Quantitative analysis revealed no other statistically significant differences. Our results provide evidence of substantial individual differences in median nerve transverse displacement in response to a neurodynamic exercise.

  17. Treatment of painful median nerve neuromas with radial and ulnar artery perforator adipofascial flaps.

    PubMed

    Adani, Roberto; Tos, Pierluigi; Tarallo, Luigi; Corain, Massimo

    2014-04-01

    To review the outcomes of 8 patients with painful median nerve neuromas at the wrist treated with external neurolysis and covered with pedicled perforator adipofascial flaps. Between 2004 and 2010, we treated 8 patients, who had a mean age of 37 years, and who had posttraumatic painful median nerve neuromas at the level of the wrist but with retained median nerve function . All of them reported neuropathic pain and had a positive Tinel's sign over the site of the presumed neuroma. The surgical procedure included external neurolysis and coverage with an ulnar artery perforator adipofascial flap (4 patients) or with a radial artery perforator adipofascial flap (4 patients). Patients were reviewed after a mean follow-up of 41 months (range, 18-84 mo). Preoperative and postoperative pain was measured with a visual analog scale. Pain improved from a preoperative mean value of 7.8 to a postoperative mean value of 3.6. There was complete resolution of pain in 5 patients, mild pain persisted in 2 patients, and 1 patient reported no improvement. No complications occurred at the donor site. Vascularized soft tissue coverage of painful median nerve neuromas is an effective treatment. We do not believe that a free flap is of any particular advantage over a local pedicle flap which we suggest using to protect the median nerve. Therapeutic IV. Copyright © 2014 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  18. Cannieu-Riche anastomosis of the ulnar to median nerve in the hand: case report.

    PubMed

    Paraskevas, G; Ioannidis, O; Martoglou, S

    2010-01-01

    We observed in a male cadaver the presence of a new type of very long Cannieu-Riche anastomosis between the proximal portion of the deep branch of the ulnar nerve for the adductor pollicis and ramus of the recurrent branch of the median nerve to the superficial head of the flexor pollicis brevis. The clinical relevance of such a communication is the possible preservation of the function of all or part of thenar muscles from the ulnar nerve in case of median nerve lesion. The ignorance of that anomaly can induce obscure clinical, surgical and electroneuromyographical findings. We report on the incidence, the double innervation and the clinical significance of Cannieu-Riche anastomosis and provide a new classification of the various types of this nerval connection.

  19. The Acupuncture Effect on Median Nerve Morphology in Patients with Carpal Tunnel Syndrome: An Ultrasonographic Study.

    PubMed

    Ural, Fatma Gülçin; Öztürk, Gökhan Tuna

    2017-01-01

    The aim of this study was to explore the acupuncture effect on the cross-sectional area (CSA) of the median nerve at the wrist in patients with carpal tunnel syndrome (CTS) and, additionally, to identify whether clinical, electrophysiological, and ultrasonographic changes show any association. Forty-five limbs of 27 female patients were randomly divided into two groups (acupuncture and control). All patients used night wrist splint. The patients in the acupuncture group received additional acupuncture therapy. Visual analog scale (VAS), Duruöz Hand Index (DHI), Quick Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire scores, electrophysiologic measurements, and median nerve CSAs were noted before and after the treatment in both groups. VAS, DHI, Quick DASH scores, and electrophysiological measurements were improved in both groups. The median nerve CSA significantly decreased in the acupuncture group, whereas there was no change in the control group. After acupuncture therapy, the patients with CTS might have both clinical and morphological improvement.

  20. The usefulness of terminal latency index of median nerve and f-wave difference between median and ulnar nerves in assessing the severity of carpal tunnel syndrome.

    PubMed

    Park, Kang Min; Shin, Kyong Jin; Park, Jinse; Ha, Sam Yeol; Kim, Sung Eun

    2014-04-01

    The calculated electrophysiological parameters, such as terminal latency index (TLI), residual latency, modified F ratio, and F-wave inversion, have been investigated as a diagnostic tool for detection of early stage of carpal tunnel syndrome (CTS) in the literature. However, the correlation of these calculated electrophysiological parameters with the clinical severity of CTS has not been reported. The aim of this study was to determine the correlation of the calculated electrophysiological parameters and clinical severity in patients with CTS. A retrospective study was performed with 212 hands of 106 CTS patients. The CTS hands were classified as asymptomatic, mild, moderate, and severe according to the clinical severity. The distal motor latency and distal motor conduction velocity of median nerve, minimal F-wave latency of median and ulnar nerves, and sensory nerve conduction velocity in the finger-wrist and palm-wrist segment of median nerve (SNCV f-w and SNCV p-w) were obtained in a conventional nerve conduction study. The TLI, residual latency, and modified F ratio of the median nerve and the difference of minimal F-wave latencies between the median and ulnar nerves (F-diff M-U) were calculated. The distal motor latency, residual latency, and F-diff M-U were significantly increased according to the clinical severity of CTS. The motor conduction velocity, SNCV p-w, SNCV f-w, TLI, and modified F ratio were significantly decreased according to the clinical severity of CTS. In analyses of variance and Kruskal-Wallis test, we used the Scheffe test as a post-hoc comparison analysis. The TLI, F-diff M-U, and SNCV f-w showed a significant difference among all groups of each CTS severity. The sensitivity, specificity, and cut-off value of TLI, F-diff M-U, and SNCV f-w between asymptomatic and mild, mild and moderate, and moderate and severe CTS groups were calculated by using receiver operating characteristic curve analysis. The cut-off values of TLI, F-diff M-U, and

  1. Morphological and positional changes of the carpal arch and median nerve during wrist compression

    PubMed Central

    Marquardt, Tamara L.; Gabra, Joseph N.; Li, Zong-Ming

    2015-01-01

    Background The carpal tunnel is a fibro-osseous structure containing the median nerve and flexor tendons. Its cross-sectional area has been shown to increase during compressive force application to the carpal bones in modeling and in vitro studies. The purpose of this study was to investigate the morphological and positional changes of the carpal arch and median nerve while in vivo compressive force was applied in the radioulnar direction across the wrist. Methods Ultrasound images of the carpal tunnel and its contents were captured for 11 healthy, female volunteers at the distal tunnel level prior to force application and during force application of 10 and 20 N. Findings With applied force, the carpal arch width significantly decreased, while the carpal arch height and area significantly increased (P < 0.001). The median nerve shape became more rounded as the compressive force magnitude increased, reflected by decreases in the nerve’s flattening ratio and increases in its circularity (P < 0.001). The applied force also resulted in nerve displacement in the radial-volar direction. Interpretation This study demonstrates that noninvasively applying radioulnar compressive force across the wrist may potentially provide relief of median nerve compression to patients suffering from carpal tunnel syndrome. PMID:25661267

  2. Effects of Wrist Posture and Fingertip Force on Median Nerve Blood Flow Velocity

    PubMed Central

    Wilson, Katherine E.; Tat, Jimmy

    2017-01-01

    Purpose. The purpose of this study was to assess nerve hypervascularization using high resolution ultrasonography to determine the effects of wrist posture and fingertip force on median nerve blood flow at the wrist in healthy participants and those experiencing carpal tunnel syndrome (CTS) symptoms. Methods. The median nerves of nine healthy participants and nine participants experiencing symptoms of CTS were evaluated using optimized ultrasonography in five wrist postures with and without a middle digit fingertip press (0, 6 N). Results. Both wrist posture and fingertip force had significant main effects on mean peak blood flow velocity. Blood flow velocity with a neutral wrist (2.87 cm/s) was significantly lower than flexed 30° (3.37 cm/s), flexed 15° (3.27 cm/s), and extended 30° (3.29 cm/s). Similarly, median nerve blood flow velocity was lower without force (2.81 cm/s) than with force (3.56 cm/s). A significant difference was not found between groups. Discussion. Vascular changes associated with CTS may be acutely induced by nonneutral wrist postures and fingertip force. This study represents an early evaluation of intraneural blood flow as a measure of nerve hypervascularization in response to occupational risk factors and advances our understanding of the vascular phenomena associated with peripheral nerve compression. PMID:28286771

  3. Importance of Tissue Morphology Relative to Patient Reports of Symptoms and Functional Limitations Resulting From Median Nerve Pathology

    PubMed Central

    Evans, Kevin D.; Li, Xiaobai; Sommerich, Carolyn M.; Case-Smith, Jane

    2013-01-01

    Significant data exist for the personal, environmental, and occupational risk factors for carpal tunnel syndrome. Few data, however, explain the interrelationship of tissue morphology to these factors among patients with clinical presentation of median nerve pathology. Therefore, our primary objective was to examine the relationship of various risk factors that may be predictive of subjective reports of symptoms or functional deficits accounting for median nerve morphology. Using diagnostic ultrasonography, we observed real-time median nerve morphology among 88 participants with varying reports of symptoms or functional limitations resulting from median nerve pathology. Body mass index, educational level, and nerve morphology were the primary predictive factors. Monitoring median nerve morphology with ultrasonography may provide valuable information for clinicians treating patients with symptoms of median nerve pathology. Sonographic measurements may be a useful clinical tool for improving treatment planning and provision, documenting patient status, or measuring clinical outcomes of prevention and rehabilitation interventions. PMID:23245784

  4. Importance of tissue morphology relative to patient reports of symptoms and functional limitations resulting from median nerve pathology.

    PubMed

    Roll, Shawn C; Evans, Kevin D; Li, Xiaobai; Sommerich, Carolyn M; Case-Smith, Jane

    2013-01-01

    Significant data exist for the personal, environmental, and occupational risk factors for carpal tunnel syndrome. Few data, however, explain the interrelationship of tissue morphology to these factors among patients with clinical presentation of median nerve pathology. Therefore, our primary objective was to examine the relationship of various risk factors that may be predictive of subjective reports of symptoms or functional deficits accounting for median nerve morphology. Using diagnostic ultrasonography, we observed real-time median nerve morphology among 88 participants with varying reports of symptoms or functional limitations resulting from median nerve pathology. Body mass index, educational level, and nerve morphology were the primary predictive factors. Monitoring median nerve morphology with ultrasonography may provide valuable information for clinicians treating patients with symptoms of median nerve pathology. Sonographic measurements may be a useful clinical tool for improving treatment planning and provision, documenting patient status, or measuring clinical outcomes of prevention and rehabilitation interventions. Copyright © 2013 by the American Occupational Therapy Association, Inc.

  5. Pudendal and median nerve sensory perception threshold: a comparison between normative studies.

    PubMed

    Quaghebeur, Jörgen; Wyndaele, Jean Jacques

    2014-12-01

    For the evaluation of sensory innervation, normative data are necessary as a comparison. To compare our current perception thresholds (CPTs) with normative data from other research. Healthy volunteers were assessed for 2000, 250, and 5 Hz CPTs of the median and pudendal nerve and data were compared with other studies. Normative data in the studied group n = 41 (male: 21; female: 20) for the median nerve, 2 kHz, 250 Hz, and 5 Hz were respectively: 241.85 ± 67.72 (140-444); 106.27 ± 39.12 (45-229); 82.05 ± 43.40 (13-271). Pudendal nerve CPTs 250 Hz were: 126.44 ± 69.46 (6-333). For men 2 kHz: 349.95 ± 125.76 (100-588); 5 Hz: 132.67 ± 51.81 (59-249) and women 2 kHz:226.20 ± 119.65 (64-528); 5 Hz: 92.45 ± 44.66 (35-215). For the median nerve no statistical differences for gender were shown. For the pudendal nerve, only 250 Hz showed no difference for gender (t-test: 0.516). Comparison of our data with CPTs of other normative data showed no agreement for the pudendal nerve. For the median nerve only 2 kHz showed agreement in three studies and for 5 Hz with one study. Comparing normative data of multiple studies shows a variety of results and poor agreement. Therefore, referring to normative data of other studies should be handled with caution.

  6. Acceptable differences in sensory and motor latencies between the median and ulnar nerves.

    PubMed

    Grossart, Elizabeth A; Prahlow, Nathan D; Buschbacher, Ralph M

    2006-01-01

    The median and ulnar nerves are often studied during the same electrodiagnostic examination. The sensory and motor latencies of these nerves have been compared to detect a common electrodiagnostic entity: median neuropathy at the wrist. However, this comparison could also be used to diagnose less common ulnar pathology. For this reason, it is important to establish normal values for comparing median and ulnar sensory and motor latencies. Previous research deriving these differences in latency has had some limitations. The purpose of this study was to derive an improved normative database for the acceptable differences in latency between the median and ulnar sensory and motor nerves of the same limb. Median and ulnar sensory and motor latencies were obtained from 219 and 238 asymptomatic risk-factor-free subjects, respectively. An analysis of variance was performed to determine whether physical characteristics, specifically age, race, gender, height, or body mass index (as an indicator of obesity), correlated with differences in latency. Differences in sensory latencies were unaffected by physical characteristics. The upper limit of normal difference between median and ulnar (median longer than ulnar) onset latency was 0.5 ms (97th percentile), whereas the peak latency value was 0.4 ms (97th percentile). The upper limit of normal difference between ulnar-versus-median (ulnar longer than median) onset latency was 0.3 ms (97th percentile), whereas the peak-latency value was 0.5 ms (97th percentile). The mean difference in motor latencies correlated with age, with older subjects having a greater variability. In subjects aged 50 and over, the mean difference in median-versus-ulnar latency was 0.9 ms +/- 0.4 ms. The upper limit of normal difference (median longer than ulnar) was 1.7 ms (97th percentile). The upper limit of normal ulnar motor latency is attained if the ulnar latency comes within 0.3 ms of the median latency. In individuals less than 50 years of age, the

  7. Blind source separation of neural activities from magnetoencephalogram in periodical median nerve stimuli.

    PubMed

    Kishida, Kuinharu

    2013-01-01

    Neural activities of cortices in periodical median nerve stimuli are studied from magnetoencephalogram. The fractional type of the decorrelation method is used for the blind source separation with temporal structure. The blind source separation method is proposed for selecting neural activities related to somatosensory stimulus from magnetoencephalogram by comparing cross-correlation functions between components of blind source separation.

  8. Magnetic Resonance Imaging Visualizes Median Nerve Entrapment due to Radius Fracture and Allows Immediate Surgical Release

    PubMed Central

    Yanagibayashi, Satoshi; Yamamoto, Naoto; Yoshida, Ryuichi; Sekido, Mitsuru

    2015-01-01

    Median nerve entrapment with forearm fracture is rare, and surgical exploration in the early stage is rarely performed. We report the case of a 19-year-old man presenting with severe pain and numbness of the thumb, index, and middle fingers and half of the ring finger along with weakness of abduction and opposition of the thumb after fracture of the radial shaft. These symptoms remained unimproved despite precise closed reduction and cast immobilization. The radius fracture was barely displaced, but complaints were increasing, particularly when the wrist and/or fingers were stretched. This suggested direct involvement of the median nerve at the fracture site, so magnetic resonance imaging (MRI) of the forearm was performed to identify any entrapment. Short tau inversion recovery MRI visualized significant deviation and entrapment of the median nerve at the fracture site. Surgical release of the entrapment was performed immediately, and complaints resolved shortly thereafter. A positive Tinel sign from the palm to the fingertips and recovery of abduction and opposition of the thumb were seen at 6 months postoperatively. This report highlights the utility of MRI for detecting median nerve entrapment at a fracture site, allowing immediate surgical release. PMID:25685575

  9. Magnetic resonance imaging and T2 relaxometry of human median nerve at 7 Tesla.

    PubMed

    Gambarota, G; Veltien, A; Klomp, D; Van Alfen, N; Mulkern, R V; Heerschap, A

    2007-09-01

    Measurements of T2 relaxation times in tissues have provided a unique, noninvasive method to investigate the microenvironment of water molecules in vivo. As more clinical imaging is performed at higher field strengths, tissue relaxation times need to be reassessed in order to optimize tissue contrast. The purpose of this study was to investigate the water proton T2 relaxation time in human median nerve at 7 T. High-resolution images of the wrist were obtained using a home-built dedicated microstrip coil. Gradient echo images provided a good anatomical delineation of the wrist structure, with a clear definition of the median nerve, tendons, bone, and connective tissue within the wrist in an acquisition time of 2 min. Measurements of the T2 relaxation time were performed with a spin echo imaging sequence. The T2 relaxation time of the median nerve was 18.3 +/- 1.9 ms, which is significantly shorter than the T2 measured in previous studies performed at 1.5 T and 3 T. Further, the T2 relaxation time of the median nerve is shorter than the T2 relaxation time of other tissues, such as brain tissue, at the same field strength. Since the T2 relaxation time of water protons is sensitive to the water microenvironment, relaxation measurements and, in general, a more quantitative magnetic resonance imaging approach might help in detecting and investigating diseases of peripheral nervous system, such as compressive and inflammatory neuropathies, in humans.

  10. Successful Treatment of Complex Regional Pain Syndrome with Pseudoaneurysm Excision and Median Nerve Neurolysis.

    PubMed

    Gillick, John L; Cooper, Jared B; Babu, Sateesh; Das, Kaushik; Murali, Raj

    2016-08-01

    Complex regional pain syndrome (CRPS), formerly referred to as reflex sympathetic dystrophy, is a pain syndrome characterized by severe pain, altered autonomic and motor function, and trophic changes. CRPS is usually associated with soft tissue injury or trauma. It has also been described as a rare complication of arterial access for angiography secondary to pseudoaneurysm formation. A 73-year-old woman underwent catheterization of the left brachial artery for angiography of the celiac artery. The following day, the patient noticed numbness and severe pain in the median nerve distribution of the left upper extremity. Over the next 6 months, the patient developed CRPS in the left hand with pain and signs of autonomic dysfunction. Further work-up revealed the formation of a left brachial artery pseudoaneurysm with impingement on the median nerve. She underwent excision of the pseudoaneurysm with decompression and neurolysis of the left median nerve. Approximately 6 weeks after surgery, the patient had noticed significant improvement in autonomic symptoms. This case involves a unique presentation of CRPS caused by brachial artery angiography and pseudoaneurysm formation. In addition, the case demonstrates the efficacy of pseudoaneurysm excision and median nerve neurolysis in the treatment of CRPS as a rare complication of arterial angiography. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Macrovascular decompression of the median nerve for posttraumatic neuralgic limb pain.

    PubMed

    Pabaney, Aqueel; Hervey-Jumper, Shawn L; Domino, Joseph; Maher, Cormac O; Yang, Lynda J S

    2013-09-01

    Neuropathic pain is rare in children, and few reports provide adequate guidelines for treatment. The authors describe the successful treatment of tardy neuropathic pain via macrovascular decompression in a 15-year-old boy who presented with progressive pain 11 years following trauma to the upper extremity that had required surgical repair of the brachial artery. Examination revealed mild chronic median and ulnar motor neuropathy as well as recent progressive lancinating pain and a Tinel sign at the prior scar. A soft tissue mass in the neurovascular bundle at the site of previous injury was noted on MRI. Surgical exploration demonstrated an altered anatomical relationship of the previously repaired brachial artery and the median nerve, resulting in pulsatile compression of the median nerve by the brachial artery. Neurolysis and decompression of the median nerve with physical separation from the brachial artery resulted in immediate pain relief. This is the first report of macrovascular decompression of a major peripheral nerve with complete symptom resolution. Noninvasive imaging together with a thorough history and physical examination can support identification of this potential etiology of peripheral neuralgic pain. Recognition and treatment of this uncommon problem may yield improved outcomes for children with neuropathic pain.

  12. Functional MRI detection of hemodynamic response of repeated median nerve stimulation.

    PubMed

    Ai, Leo; Oya, Hiroyuki; Howard, Matthew; Xiong, Jinhu

    2013-05-01

    Median nerve stimulation is a commonly used technique in the clinical setting to determine areas of neuronal function in the brain. Neuronal activity of repeated median nerve stimulation is well studied. The cerebral hemodynamic response of the stimulation, on the other hand, is not very clear. In this study, we investigate how cerebral hemodynamics behave over time using the same repeated median nerve stimulation. Ten subjects received constant repeated electrical stimulation to the right median nerve. Each subject had functional magnetic resonance imaging scans while receiving said stimulations for seven runs. Our results show that the blood oxygen level-dependent (BOLD) signal significantly decreases across each run. Significant BOLD signal decreases can also be seen within runs. These results are consistent with studies that have studied the hemodynamic habituation effect with other forms of stimulation. However, the results do not completely agree with the findings of studies where evoked potentials were examined. Thus, further inquiry of how evoked potentials and cerebral hemodynamics are coupled when using constant stimulations is needed. Copyright © 2013 Elsevier Inc. All rights reserved.

  13. Median nerve ultrasound in diabetic peripheral neuropathy with and without carpal tunnel syndrome.

    PubMed

    Hassan, Anhar; Leep Hunderfund, Andrea N; Watson, James; Boon, Andrea J; Sorenson, Eric J

    2013-03-01

    Median nerve ultrasound shows increased cross-sectional area (CSA) in carpal tunnel syndrome (CTS) and diabetic peripheral neuropathy (PN). The role of ultrasound in diagnosing CTS superimposed on diabetic PN is unknown. The objective of this study is to evaluate ultrasound for diagnosis of CTS in diabetic PN. Prospective recruitment of diabetics with electrodiagnostically proven PN, subdivided into cases (with CTS) or controls (without CTS). The gold standard for CTS was clinical diagnosis. NCS were correlated with blinded median nerve CSA ultrasound measurements. Eight cases (CTS) and eight controls (no CTS) were recruited. Nerve conduction studies (NCS): Median nerve distal latencies (antidromic sensory; palmar; lumbrical motor; and lumbrical motor to ulnar interosseous difference) were significantly prolonged in CTS cases. No ultrasound measurement (distal median CSA, wrist-forearm ratio, wrist-forearm difference) reached significance to detect CTS. Area under the curve was greatest for lumbrical distal latency by receiver operator characteristic analysis (0.85). In this pilot study, NCS may be superior to ultrasound for identification of superimposed CTS in diabetic PN patients, but larger numbers are needed for confirmation. Copyright © 2012 Wiley Periodicals, Inc., a Wiley company.

  14. Ultrasound assessment of the effectiveness of carpal tunnel release on median nerve deformation.

    PubMed

    Yoshii, Yuichi; Ishii, Tomoo; Tung, Wen-lin

    2015-05-01

    To assess the biomechanical effect of carpal tunnel release (CTR), we evaluated the deformation and displacement patterns of the median nerve before and after CTR in carpal tunnel syndrome (CTS) patients. Sixteen wrists of 14 idiopathic CTS patients who had open CTR and 26 wrists of 13 asymptomatic volunteers were evaluated by ultrasound. Cross-sectional images of the carpal tunnel during motion from full finger extension to flexion were recorded. The area, perimeter, aspect ratio of a minimum enclosing rectangle, and circularity of the median nerve were measured in finger extension and flexion positions. Deformation indices, determined by the flexion-extension ratio for each parameter, were compared before and after CTR. After CTR, the deformation indices of perimeter and circularity became significantly larger and the aspect ratio became significantly smaller than those before CTR (p < 0.05). Those differences were more obvious when comparing the values between the patients before CTR and the controls. Since the deformation indices after CTR are similar to the patterns of normal subjects, the surrounding structures and environment of the median nerve may be normalized upon CTR. This may be a way to tell how the median nerves recover after CTR. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  15. Effect of wrist angle on median nerve appearance at the proximal carpal tunnel.

    PubMed

    Loh, Ping Yeap; Muraki, Satoshi

    2015-01-01

    This study investigated the effects of wrist angle, sex, and handedness on the changes in the median nerve cross-sectional area (MNCSA) and median nerve diameters, namely longitudinal diameter (D1) and vertical diameter (D2). Ultrasound examination was conducted to examine the median nerve at the proximal carpal tunnel in both dominant and nondominant hands of men (n = 27) and women (n = 26). A total of seven wrist angles were examined: neutral; 15°, 30°, and 45° extension; and 15°, 30°, and 45° flexion. Our results indicated sexual dimorphism and bilateral asymmetry of MNCSA, D1 and D2 measurements. MNCSA was significantly reduced when the wrist angle changed from neutral to flexion or extension positions. At flexion positions, D1 was significantly smaller than that at neutral. In contrast, at extension positions, D2 was significantly smaller than that at neutral. In conclusion, this study showed that MNCSA decreased as the wrist angle changed from neutral to flexion or extension positions in both dominant and nondominant hands of both sexes, whereas deformation of the median nerve differed between wrist flexion and extension.

  16. Effect of Wrist Angle on Median Nerve Appearance at the Proximal Carpal Tunnel

    PubMed Central

    Loh, Ping Yeap; Muraki, Satoshi

    2015-01-01

    This study investigated the effects of wrist angle, sex, and handedness on the changes in the median nerve cross-sectional area (MNCSA) and median nerve diameters, namely longitudinal diameter (D1) and vertical diameter (D2). Ultrasound examination was conducted to examine the median nerve at the proximal carpal tunnel in both dominant and nondominant hands of men (n = 27) and women (n = 26). A total of seven wrist angles were examined: neutral; 15°, 30°, and 45° extension; and 15°, 30°, and 45° flexion. Our results indicated sexual dimorphism and bilateral asymmetry of MNCSA, D1 and D2 measurements. MNCSA was significantly reduced when the wrist angle changed from neutral to flexion or extension positions. At flexion positions, D1 was significantly smaller than that at neutral. In contrast, at extension positions, D2 was significantly smaller than that at neutral. In conclusion, this study showed that MNCSA decreased as the wrist angle changed from neutral to flexion or extension positions in both dominant and nondominant hands of both sexes, whereas deformation of the median nerve differed between wrist flexion and extension. PMID:25658422

  17. Bilateral carpal tunnel syndrome secondary to tophaceous compression of the median nerves.

    PubMed

    Tsai, C Y; Yu, C L; Tsai, S T

    1996-01-01

    A 65-year-old man with long-term gouty arthritis developed bilateral carpal tunnel syndrome. At surgery a chalky substance, which showed negative birefringence on polarized microscopy, was found infiltrating around the intensely inflamed transverse carpal ligaments. In differential diagnosis of carpal tunnel syndrome, tophaceous compression over the median nerve should be taken into consideration.

  18. Effect of the Steindler procedure on the median nerve branches to the medial epicondylar muscles.

    PubMed

    Chantelot, C; Feugas, C; Migaud, H; Guillem, F; Chapnikoff, D; Fontaine, C

    2000-06-01

    Usually the median nerve gives off six branches to the muscles arising from the medial epicondyle, which could be tightened during Steindler's procedure. We studied these branches before and after Steindler's procedure in 20 fresh cadavers and observed a considerable variation in the origin of the branches. The muscular branches arising from the median nerve did not seem to limit the mobilization of the medial epicondyle when performing Steindler's transfer. The limitation of the flexion observed after Steindler's procedure was mainly related to the tension of the transferred forearm flexor muscles. The variability of the origin of the branch to the flexor digitorum superficialis muscle could explain a lesion of this branch when Steindler's procedure is carried out with Brunelli's modification. The lateral transfer and the anterior transfer on to the humeral shaft did not influence the limitation of elbow flexion or result in tightness in any nerve branch to the transferred muscles.

  19. Prevalence of bifid median nerves and persistent median arteries and their association with carpal tunnel syndrome in a sample of latino poultry processors and other manual workers

    PubMed Central

    WALKER, FRANCIS O.; CARTWRIGHT, MICHAEL S.; BLOCKER, JILL N.; ARCURY, THOMAS A.; SUK, JUNG IM; CHEN, HAIYING; SCHULTZ, MARK R.; GRZYWACZ, JOSEPH G.; MORA, DANA C.; QUANDT, SARA A.

    2013-01-01

    Introduction The prevalence of bifid median nerves and persistent median arteries, their co-occurrence, and their relationship to carpal tunnel syndrome (CTS) are only understood partially. Methods We screened 1026 wrists of 513 Latino manual laborers in North Carolina for bifid median nerves and persistent median arteries using electrodiagnosis and ultrasound. Results A total of 8.6% of wrists had a bifid median nerve, and 3.7% of wrists had a persistent median artery independent of subgroup ethnicity, age, gender, or type of work. An association with definite carpal tunnel syndrome was not found. The presence of either anatomic variant was associated with a high likelihood of co-occurrence of another variant in the same or the contralateral wrist. Conclusions The occurrence of median anatomic variants can be determined in field studies using ultrasound. Persistent median arteries and bifid median nerves tend to co-occur but do not put manual laborers at additional risk of developing CTS. PMID:24037717

  20. Prevalence of bifid median nerves and persistent median arteries and their association with carpal tunnel syndrome in a sample of Latino poultry processors and other manual workers.

    PubMed

    Walker, Francis O; Cartwright, Michael S; Blocker, Jill N; Arcury, Thomas A; Suk, Jung I M; Chen, Haiying; Schulz, Mark R; Schultz, Mark R; Grzywacz, Joseph G; Mora, Dana C; Quandt, Sara A

    2013-10-01

    The prevalence of bifid median nerves and persistent median arteries, their co-occurrence, and their relationship to carpal tunnel syndrome (CTS) are only understood partially. We screened 1026 wrists of 513 Latino manual laborers in North Carolina for bifid median nerves and persistent median arteries using electrodiagnosis and ultrasound. A total of 8.6% of wrists had a bifid median nerve, and 3.7% of wrists had a persistent median artery independent of subgroup ethnicity, age, gender, or type of work. An association with definite carpal tunnel syndrome was not found. The presence of either anatomic variant was associated with a high likelihood of co-occurrence of another variant in the same or the contralateral wrist. The occurrence of median anatomic variants can be determined in field studies using ultrasound. Persistent median arteries and bifid median nerves tend to co-occur but do not put manual laborers at additional risk of developing CTS. Copyright © 2013 Wiley Periodicals, Inc.

  1. ANATOMIC STUDY OF THE NERVOUS COMMUNICATION BETWEEN THE MEDIAN AND MUSCULOUCUTANEOUS NERVE

    PubMed Central

    Caetano, Edie Benedito; Vieira, Luiz Ângelo; Cavalheiro, Cristina Schmitt; Razuk, Mauro; Almargo, Marco Antonio Pires; Caetano, Mauricio Ferreira

    2016-01-01

    ABSTRACT Objective: The aim of this study was to analyze the incidence of nerve communication between the musculocutaneous and median nerve. Methods: Anatomical dissection of 40 limbs from 20 fetal cadavers was performed at the Laboratory of Anatomy, Faculdade de Ciências Médicas e da Saúde da Pontifícia Universidade Católica de São Paulo. Results: A communicating branch was found in 10 upper limbs. In nine limbs there was a musculocutaneous-median anastomosis (type I); and in one limb there was a median-musculocutaneous anastomosis (type II). Conclusion: It is very important to know these anatomical variations, especially when considering clinical examination, diagnostic, prognostic and surgical treatment. Level of Evidence IV, Case Series. PMID:28243174

  2. ANATOMIC STUDY OF THE NERVOUS COMMUNICATION BETWEEN THE MEDIAN AND MUSCULOUCUTANEOUS NERVE.

    PubMed

    Caetano, Edie Benedito; Vieira, Luiz Ângelo; Cavalheiro, Cristina Schmitt; Razuk, Mauro; Almargo, Marco Antonio Pires; Caetano, Mauricio Ferreira

    2016-01-01

    The aim of this study was to analyze the incidence of nerve communication between the musculocutaneous and median nerve . Anatomical dissection of 40 limbs from 20 fetal cadavers was performed at the Laboratory of Anatomy, Faculdade de Ciências Médicas e da Saúde da Pontifícia Universidade Católica de São Paulo . A communicating branch was found in 10 upper limbs. In nine limbs there was a musculocutaneous-median anastomosis (type I); and in one limb there was a median-musculocutaneous anastomosis (type II) . It is very important to know these anatomical variations, especially when considering clinical examination, diagnostic, prognostic and surgical treatment. Level of Evidence IV, Case Series.

  3. Sleep deprivation aggravates median nerve injury-induced neuropathic pain and enhances microglial activation by suppressing melatonin secretion.

    PubMed

    Huang, Chun-Ta; Chiang, Rayleigh Ping-Ying; Chen, Chih-Li; Tsai, Yi-Ju

    2014-09-01

    Sleep deprivation is common in patients with neuropathic pain, but the effect of sleep deprivation on pathological pain remains uncertain. This study investigated whether sleep deprivation aggravates neuropathic symptoms and enhances microglial activation in the cuneate nucleus (CN) in a median nerve chronic constriction injury (CCI) model. Also, we assessed if melatonin supplements during the sleep deprived period attenuates these effects. Rats were subjected to sleep deprivation for 3 days by the disc-on-water method either before or after CCI. In the melatonin treatment group, CCI rats received melatonin supplements at doses of 37.5, 75, 150, or 300 mg/kg during sleep deprivation. Melatonin was administered at 23:00 once a day. Male Sprague-Dawley rats, weighing 180-250 g (n = 190), were used. Seven days after CCI, behavioral testing was conducted, and immunohistochemistry, immunoblotting, and enzyme-linked immunosorbent assay were used for qualitative and quantitative analyses of microglial activation and measurements of proinflammatory cytokines. In rats who underwent post-CCI sleep deprivation, microglia were more profoundly activated and neuropathic pain was worse than those receiving pre-CCI sleep deprivation. During the sleep deprived period, serum melatonin levels were low over the 24-h period. Administration of melatonin to CCI rats with sleep deprivation significantly attenuated activation of microglia and development of neuropathic pain, and markedly decreased concentrations of proinflammatory cytokines. Sleep deprivation makes rats more vulnerable to nerve injury-induced neuropathic pain, probably because of associated lower melatonin levels. Melatonin supplements to restore a circadian variation in melatonin concentrations during the sleep deprived period could alleviate nerve injury-induced behavioral hypersensitivity. © 2014 Associated Professional Sleep Societies, LLC.

  4. Median Nerve Stimulation in a Patient with Complex Regional Pain Syndrome Type II.

    PubMed

    Jeon, Ik-Chan; Kim, Min-Su; Kim, Seong-Ho

    2009-09-01

    A 54-year-old man experienced injury to the second finger of his left hand due to damage from a paintball gun shot 8 years prior, and the metacarpo-phalangeal joint was amputated. He gradually developed mechanical allodynia and burning pain, and there were trophic changes of the thenar muscle and he reported coldness on his left hand and forearm. A neuroma was found on the left second common digital nerve and was removed, but his symptoms continued despite various conservative treatments including a morphine infusion pump on his left arm. We therefore attempted median nerve stimulation to treat the chronic pain. The procedure was performed in two stages. The first procedure involved exposure of the median nerve on the mid-humerus level and placing of the electrode. The trial stimulation lasted for 7 days and the patient's symptoms improved. The second procedure involved implantation of a pulse generator on the left subclavian area. The mechanical allodynia and pain relief score, based on the visual analogue scale, decreased from 9 before surgery to 4 after surgery. The patient's activity improved markedly, but trophic changes and vasomotor symptom recovered only moderately. In conclusion, median nerve stimulation can improve chronic pain from complex regional pain syndrome type II.

  5. Superficial brachial artery: A possible cause for idiopathic median nerve entrapment neuropathy.

    PubMed

    Nkomozepi, Pilani; Xhakaza, Nkosi; Swanepoel, Elaine

    2017-02-15

    Nerve entrapment syndromes occur because of anatomic constraints at specific locations in both upper and lower limbs. Anatomical locations prone to nerve entrapment syndromes include sites where a nerve courses through fibro-osseous or fibromuscular tunnels or penetrates a muscle. The median nerve (MN) can be entrapped by the ligament of Struthers; thickened biceps aponeurosis; between the superficial and deep heads of the pronator teres muscle and by a thickened proximal edge of flexor digitorum superficialis muscle. A few cases of MN neuropathies encountered are reported to be idiopathic. The superficial branchial artery (SBA) is defined as the artery running superficial to MN or its roots. This divergence from normal anatomy may be the possible explanation for idiopathic median nerve entrapment neuropathy. This study presents three cases with unilateral presence of the SBA encountered during routine undergraduate dissection at the University of Johannesburg. Case 1: SBA divided into radial and ulnar arteries. Brachial artery (BA) terminated as deep brachial artery. Case 2: SBA continued as radial artery (RA). BA terminated as ulnar artery (UA), anterior and posterior interosseous arteries. Case 3: SBA continued as UA. BA divided into radial and common interosseous arteries. Arteries that take an unusual course are more vulnerable to iatrogenic injury during surgical procedures and may disturb the evaluation of angiographic images during diagnosis. In particular, the presence of SBA may be a course of idiopathic neuropathies.

  6. Computer keyboarding biomechanics and acute changes in median nerve indicative of carpal tunnel syndrome.

    PubMed

    Toosi, Kevin K; Hogaboom, Nathan S; Oyster, Michelle L; Boninger, Michael L

    2015-07-01

    Carpal tunnel syndrome is a common and costly peripheral neuropathy. Occupations requiring repetitive, forceful motions of the hand and wrist may play a role in the development of carpal tunnel syndrome. Computer keyboarding is one such task, and has been associated with upper-extremity musculoskeletal disorder development. The purpose of this study was to determine whether continuous keyboarding can cause acute changes in the median nerve and whether these changes correlate with wrist biomechanics during keyboarding. A convenience sample of 37 healthy individuals performed a 60-minute typing task. Ultrasound images were collected at baseline, after 30 and 60 min of typing, then after 30 min of rest. Kinematic data were collected during the typing task. Variables of interest were median nerve cross-sectional area, flattening ratio, and swelling ratio at the pisiform; subject characteristics (age, gender, BMI, wrist circumference, typing speed) and wrist joint angles. Cross-sectional area and swelling ratio increased after 30 and 60 min of typing, and then decreased to baseline after 30 min of rest. Peak ulnar deviation contributed to changes in cross-sectional area after 30 min of typing. Results from this study confirmed a typing task causes changes in the median nerve, and changes are influenced by level of ulnar deviation. Furthermore, changes in the median nerve are present until cessation of the activity. While it is unclear if these changes lead to long-term symptoms or nerve injury, their existence adds to the evidence of a possible link between carpal tunnel syndrome and keyboarding. Published by Elsevier Ltd.

  7. A study of the sympathetic skin response and sensory nerve action potential after median and ulnar nerve repair.

    PubMed

    Jazayeri, M; Ghavanini, M R; Rahimi, H R; Raissi, G R

    2003-01-01

    The purpose of this study was to compare SSR with sensory nerve action potential (SNAP) responses in regeneration of injured peripheral nerves after nerve repair. We studied 10 male patients with a mean age of 26.7 years. All the patients had complete laceration of median or ulnar nerves. The patients were followed up at least for six months. SSR and SNAP assessment were performed every one to two months. Normal hands were used as controls. SSR was positive after 15.8 +/- 9.4 weeks (mean +/- 2 SD) and SNAP after 27.8 +/- 12.9 weeks (mean +/- 2 SD). The difference was statistically significant (P value < 0.001). This can be due to more rapid growth of sympathetic unmyelinated fibers relative to sensory myelinated fibers. This study also shows that recovery of the sudomotor activity following nerve repair is satisfactory in general and SSR can be used as a useful and sensitive method in the evaluation of sudomotor nerve regeneration.

  8. Long term recovery of median nerve repair using laser-activated chitosan adhesive films.

    PubMed

    Barton, Matthew J; Morley, John W; Stoodley, Marcus A; Shaikh, Sumaiya; Mahns, David A; Lauto, Antonio

    2015-03-01

    Sutures remain the standard peripheral nerve repair technique, whether applied directly or indirectly to nerve tissue. Unfortunately, significant postoperative complications can result, such as inflammation, neuroma formation and foreign body reactions. Photochemical-tissue-bonding (PTB) using rose Bengal (RB) integrated into a chitosan bioadhesive is an alternative nerve repair device that removes the need for sutures. Rats were arranged into three groups: RB-chitosan adhesives-repair, end-to-end epineural suture-repair (surgical standard) and sham laser-irradiated control. Groups were compared through histological assessment, electrophysiological recordings and grip motor strength. RB-chitosan adhesive repaired nerves displayed comparable results when compared to the standard suture-repair based on histological and electrophysiological findings. Functionally, RB-chitosan adhesive was associated with a quicker and more pronounced recovery of grip force when compared to the suture-repair. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. An ultrasonographic assessment of nerve stimulation-guided median nerve block at the elbow: a local anesthetic spread, nerve size, and clinical efficacy study.

    PubMed

    Dufour, Eric; Cymerman, Alexandre; Nourry, Gérard; Balland, Nicolas; Couturier, Christian; Liu, Ngai; Dreyfus, Jean-François; Fischler, Marc

    2010-08-01

    Nerve stimulation is an effective technique for peripheral nerve blockade. However, the local anesthetic (LA) distribution pattern obtained with this blind approach is unknown and may explain its clinical effects. One hundred patients received a median nerve block at the elbow using a nerve stimulator approach. After correct needle placement defined by a minimal stimulating current < or = 0.5 mA (2 Hz, 0.1 millisecond), 6 mL lidocaine 1.5%with epinephrine 1:200,000 was injected. A linear 5- to 13-MHz probe (12L-RS) was used to assess a cross-section area of median nerve, which was calculated by 3 consecutive measurements before and after injection, and LA circumferential spread around the nerve during static and longitudinal examination. Intraneural injection defined as an increase in nerve area was detected using an iterative method for outlier detection. Results of sensory tests (cold and light touch) on 3 nerve territories and of motor blockade were compared with the imaging aspects. We performed clinical neurological examination at 3 days and 1 month after block. Nerve swelling, considered significant when an increase in cross-sectional area was > or = 75%, was observed in 43 patients. Nerve swelling associated with a circumferential LA spread image, present in 37 patients, was associated with a sensory success rate of 86%. The success rate was 34% for 32 patients in whom none of these signs was visualized. A circumferential spread around a nonswollen nerve, present in 25 patients, was followed by a sensory success rate of 76% within the 30-minute evaluation period. No major early neurological complications were observed. Nerve stimulation does not prevent intraneural injection. In the absence of intraneural injection, the presence of circumferential LA spread image seemed predictive of successful sensory block in almost 75% of the cases within the 30-minute evaluation period.

  10. Ultrasonographic assessment of longitudinal median nerve and hand flexor tendon dynamics in carpal tunnel syndrome.

    PubMed

    Korstanje, Jan-Wiebe H; Scheltens-De Boer, Marjan; Blok, Joleen H; Amadio, Peter C; Hovius, Steven E R; Stam, Henk J; Selles, Ruud W

    2012-05-01

    Changes in subsynovial connective tissue (SSCT) in carpal tunnel syndrome (CTS) patients may result in altered dynamics; consequently, quantification of these dynamics might support objective diagnosis of CTS. We measured and compared longitudinal excursion of the flexor digitorum superficialis and profundus tendons, the median nerve, and the SSCT between the most and least affected hands of 51 CTS patients during extension-to-fist motion. Median nerve and flexor digitorum superficialis tendon excursions in the most affected hands were smaller than in the least affected hands of the same patients, whereas the excursions of the flexor digitorum profundus were larger. Based on these excursions, logistic regression models classified between 67% and 86% of the hands correctly as having CTS. The altered hand dynamics in CTS patients may have implications for the pathophysiology and clinical evaluation of CTS, and ultrasound-based classification models may further support the diagnosis of CTS. Copyright © 2012 Wiley Periodicals, Inc.

  11. Pigmented villonodular synovitis of the elbow with rdial, median and ulnar nerve compression

    PubMed Central

    Lu, Hui; Chen, Qiang; Shen, Hui

    2015-01-01

    Pigmented villonodular synovitis (PVNS) is a rare, idiopathic proliferative disorder of the synovium. While, PVNS of elbow is extremely rare. We report an 82-year-old female patient with 20-year-history of gradually increased PVNS in her left elbow. The multiple masses were located in anterior, medial and lateral of elbow. Her radial, median and ulnar nerves were compressed by the tumor. We resected tumor of extra-articular part piecemeally and released the compression of nerves. After the surgery, the patient gained a functional recovery. Two years after surgery she had a tumor recurrence, but without any symptoms of nerve compression syndromes. We discussed its clinical diagnosis, radiological features, MRI findings, pathophysiology, and treatment. PMID:26823718

  12. Pigmented villonodular synovitis of the elbow with rdial, median and ulnar nerve compression.

    PubMed

    Lu, Hui; Chen, Qiang; Shen, Hui

    2015-01-01

    Pigmented villonodular synovitis (PVNS) is a rare, idiopathic proliferative disorder of the synovium. While, PVNS of elbow is extremely rare. We report an 82-year-old female patient with 20-year-history of gradually increased PVNS in her left elbow. The multiple masses were located in anterior, medial and lateral of elbow. Her radial, median and ulnar nerves were compressed by the tumor. We resected tumor of extra-articular part piecemeally and released the compression of nerves. After the surgery, the patient gained a functional recovery. Two years after surgery she had a tumor recurrence, but without any symptoms of nerve compression syndromes. We discussed its clinical diagnosis, radiological features, MRI findings, pathophysiology, and treatment.

  13. Recurrent Primary Synovial Sarcoma of Median Nerve: A Case Report and Literature Review.

    PubMed

    Bhat, A K; Jayakrishnan, K N; Acharya, A M

    2016-10-01

    We report a case of intraneural synovial sarcoma of the median nerve in a 39 year old lady with multiple local recurrences over thirteen years with no distant metastasis. The diagnosis of biphasic type of synovial sarcoma was confirmed by histopathology and immunohistochemistry. At the time of the fourth recurrence below elbow amputation was performed. This case is being reported for its rarity and propensity for local recurrence without distant metastasis.

  14. Morphine and endorphins modulate dopamine turnover in rat median eminence.

    PubMed Central

    Deyo, S N; Swift, R M; Miller, R J

    1979-01-01

    The is evidence that some of the actions of both endogenous and exogenous opioids (e.g., stimulation of prolactin release) are mediated by interaction with catecholaminergic systems. Morphine (1.67, 5, and 15 mg/kg of body weight, intraperitoneally) altered dopamine turnover as measured by the alpha-methyl-p-tyrosine method in the median eminence, neostriatum, and frontal cortex of male Sprague-Dawley rats. The turnover rate of dopamine was reduced in the median eminence and frontal cortex but accelerated in the neostriatum. In the frontal cortex all doses were effective in decreasing dopamine turnover; however, in the median eminence the lowest dose of morphine did not significantly alter dopamine turnover. All three doses accelerated dopamine turnover in the neostriatum. Naloxone effectively reversed the effects of morphine at all doses in all brain areas, whereas it had no effect on turnover when given alone. In the median eminence, neostriatum, and frontal cortex, intraventricular injection of [D-Ala2,D-Leu5]-enkephalin (25 micrograms) or beta-endorphin (15 micrograms) produced the same effects on dopamine turnover as morphine. The actions of these peptides were blocked by naloxone. It is hypothesized that opiates and opioid peptides increase prolactin release by reducing the activity of the tuberoinfundibular dopaminergic system. PMID:288082

  15. Lipofibromatous hamartoma of the median nerve: A case report and review of the literature

    PubMed Central

    Patil, V. S.; Nagle, Sunila

    2009-01-01

    A case of lipofibromatous hamartoma of the median nerve in an adult is described in this article. A 33-year-old male presented with tingling, numbness and swelling in the palm of the left non dominant hand that had been present for a few months. Examination revealed that there was fullness in the volar aspect of the wrist and in the inter-thenar area. Another mass was present at the base of the index finger, which appeared to be involving subcutaneous tissues. The clinical diagnosis was carpal tunnel syndrome due to a space occupying tumor mass in the carpal tunnel. On exploration of the carpal tunnel, a large median nerve was seen 4 cm proximal to the wrist crease line and extending distally until it divided into its branches. Another mass was present at the base of the index finger, which was adherent to the skin. The radial digital nerve of the index finger was normal in size. For the enlarged nerve, an epineurotomy was performed and a biopsy was taken. Another biopsy was taken from the distal mass. His postoperative period was uneventful. In July 2004, at the end of 5 years, the patient had no symptoms and the size of the tumor had not increased. PMID:19881034

  16. Sonographic examination of the median nerve in dialysis patients and after renal transplantation.

    PubMed

    Carolus, Anne Elisabeth; Schenker, Peter; Dombert, Thomas; Fontana, Johann; Viebahn, Richard; Schmieder, Kirsten; Brenke, Christopher

    2015-12-01

    Patients with renal insufficiency are predisposed to develop CTS (carpal tunnel syndrome). In particular, long-term dialysis seems to contribute to changes in median nerve texture which lead to an increased risk for CTS. The current study was designed to evaluate if these structural changes can be detected by HRS (high-resolution sonography). Additionally, the current study aimed to determine if changes are reversible after termination of dialysis. Fifty patients (98 hands) were included in the study. The study population was subdivided into three groups: patients without any history of renal disease (H, n = 20), patients with long-term dialysis (D, n = 10), and patients after renal transplantation (TX, n = 20). None of the patients had any clinical symptoms for a median nerve compression syndrome. The CSA (cross-sectional area) of the median nerve was evaluated both 12 cm proximally of the carpal tunnel inlet and directly at the carpal tunnel inlet. The ratio of those two values, the WFR (wrist forearm ratio), was calculated and analyzed. The CSA demonstrated significantly higher values in dialysis (D) and transplanted (TX) patients compared to the healthy (H) control group (P < 0.001). No significant differences were detectable between the D and TX groups. Specifically, there was no significant difference in the WFR. Patients with chronic renal disease demonstrate significantly higher CSA values compared to their healthy counterparts. Termination of dialysis does not seem to reverse these morphological changes.

  17. [Relationship between ultrasound measurements of the median nerve and electrophysiological severity in carpal tunnel syndrome].

    PubMed

    Bueno-Gracia, Elena; Tricás-Moreno, José Miguel; Fanlo-Mazas, Pablo; Malo-Urriés, Miguel; Haddad-Garay, María; Estébanez-de-Miguel, Elena; Hidalgo-García, César; Ruiz-de-Escudero Zapico, Alazne

    2015-11-16

    Ultrasonography is a tool that has advanced a great deal in the diagnosis of neural compressive pathologies, such as carpal tunnel syndrome (CTS). In order to plan the treatment it is important to establish the severity of the pathology, which means that it would be important to know the capacity of ultrasonography to determine the extent to which the median nerve is compromised at this level. To investigate the correlation between ultrasound measurements and electrophysiological severity in patients with CTS. Ultrasound measurements were performed with 59 subjects (97 wrists) who were referred to have an electroneurogram (ENG) due to suspected CTS. According to the ENG, the subjects were classified as healthy, mild, moderate or severe CTS. The relationship between the ultrasound measurements and the results of the ENG were later analysed in terms of their severity. The ROC (receiver operating characteristic) curves were calculated for the optimal cut-off values in each group, taking into account their severity. Both ultrasound measurements showed a correlation with the severity of the CTS determined by ENG. The cross-sectional area of the median nerve in the wrist (CSA-W) showed the highest correlation (r = 0.613). There is a relation between the ultrasound measurements of the median nerve, especially in the CSA-W, and the severity of CTS in the clinical context. These measurements could be used as complementary data to diagnose CTS and to determine its severity.

  18. The Reliability of Ultrasound Measurements of the Median Nerve at the Carpal Tunnel Inlet.

    PubMed

    Fowler, John R; Hirsch, David; Kruse, Kevin

    2015-10-01

    To determine the interrater and intra-rater reliability of ultrasound (US) measurement of the cross-sectional area (CSA) of the median nerve at the carpal tunnel inlet. Three examiners of varying levels of experience performed US measurements of the CSA of the median nerve at the carpal tunnel inlet of both wrists of 11 healthy volunteers. Each examiner was blinded to the measurements of the other examiners. The measurements were repeated 2 weeks later in random order to test intra-rater reliability. The Lin concordance correlation coefficient (LCCC) for interrater and intra-rater reliability was calculated. The overall inter-rater LCCC was 0.59 (95% confidence interval [CI], 0.41-0.73). Intra-rater LCCC varied based on examiner experience. The senior author had an intra-rater LCCC of 0.91 (95% CI, 0.80-0.96), the hand fellow had an intra-rater LCCC of 0.45 (95% CI, 0.17-0.66), and the first-year resident had an intra-rater LCCC of 0.78 (95% CI, 0.55-0.90). There is moderate agreement among examiners of varying levels of experience when measuring the CSA of the median nerve at the carpal tunnel inlet. Examiner experience affected intra-rater reliability of measurements; an experienced examiner had nearly perfect agreement compared with moderate agreement for less experienced examiners. Copyright © 2015 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  19. Carpal arch and median nerve changes during radioulnar wrist compression in carpal tunnel syndrome patients

    PubMed Central

    Marquardt, Tamara L.; Evans, Peter J.; Seitz, William H.; Li, Zong-Ming

    2015-01-01

    The purpose of this study was to investigate the morphological changes of the carpal arch and median nerve during the application of radiounlarly directed compressive force across the wrist in patients with carpal tunnel syndrome. Radioulnar compressive forces of 10 N and 20 N were applied at the distal level of the carpal tunnel in 10 female patients diagnosed with carpal tunnel syndrome. Immediately prior to force application and after 3 minutes of application, ultrasound images of the distal carpal tunnel were obtained. It was found that applying force across the wrist decreased the carpal arch width (p < 0.001) and resulted in increased carpal arch height (p < 0.01), increased carpal arch curvature (p < 0.001), and increased radial distribution of the carpal arch area (p < 0.05). It was also shown that wrist compression reduced the flattening of the median nerve, as indicated by changes in the nerve’s circularity and flattening ratio (p < 0.001). Statement of clinical significance This study demonstrated that the carpal arch can be non-invasively augmented by applying compressive force across the wrist, and that this strategy may decompress the median nerve providing symptom relief to patients with carpal tunnel syndrome. PMID:26662276

  20. Microneurography in relation to intraneural topography: somatotopic organisation of median nerve fascicles in humans.

    PubMed Central

    Hallin, R G

    1990-01-01

    Microneurography was performed in median nerve sensory fascicles with concentric needle electrodes and with conventional tungsten microneedles. The latter electrodes preferentially recorded activity from the myelinated fibres in the whole fascicle. By contrast, due to its special design, a concentric needle can record activity selectively from even a small part of a fascicle. High amplitude signals in C fibres can be discriminated close to Schwann cells that envelope unmyelinated axons. Apart from being biased for activity in thin fibres, the concentric needles can also record signals from nearby myelinated fibres. The palmar receptive fields of such fibre groups were not congruent with the areas traditionally attributed to multiunit skin afferents in humans, namely the innervation zone(s) of one or two adjacent digital nerve(s). Instead, the multiunit fields often comprised small parts of a digital nerve innervation area, frequently only the pulp of a finger. Single units were always localised within previously screened multiunit areas. Contrary to some previously accepted tenets it is probable that single unit activity in myelinated fibres in these studies is recorded extra-axonally near to a node of Ranvier. The findings also suggest the presence of a somatotopy in human limb nerve fascicles, comparable to that previously established in the spinal cord and the somatosensory cortex. Images PMID:2246655

  1. Effects of grip force on median nerve deformation at different wrist angles

    PubMed Central

    Nakashima, Hiroki; Muraki, Satoshi

    2016-01-01

    The present study investigated the effects of grip on changes in the median nerve cross-sectional area (MNCSA) and median nerve diameter in the radial-ulnar direction (D1) and dorsal-palmar direction (D2) at three wrist angles. Twenty-nine healthy participants (19 men [mean age, 24.2 ± 1.6 years]; 10 women [mean age, 24.0 ± 1.6 years]) were recruited. The median nerve was examined at the proximal carpal tunnel region in three grip conditions, namely finger relaxation, unclenched fist, and clenched fist. Ultrasound examinations were performed in the neutral wrist position (0°), at 30°wrist flexion, and at 30°wrist extension for both wrists. The grip condition and wrist angle showed significant main effects (p < 0.01) on the changes in the MNCSA, D1, and D2. Furthermore, significant interactions (p < 0.01) were found between the grip condition and wrist angle for the MNCSA, D1, and D2. In the neutral wrist position (0°), significant reductions in the MNCSA, D1, and D2 were observed when finger relaxation changed to unclenched fist and clenched fist conditions. Clenched fist condition caused the highest deformations in the median nerve measurements (MNCSA, approximately −25%; D1, −13%; D2, −12%). The MNCSA was significantly lower at 30°wrist flexion and 30°wrist extension than in the neutral wrist position (0°) at unclenched fist and clenched fist conditions. Notably, clenched fist condition at 30°wrist flexion showed the highest reduction of the MNCSA (−29%). In addition, 30°wrist flexion resulted in a lower D1 at clenched fist condition. In contrast, 30°wrist extension resulted in a lower D2 at both unclenched fist and clenched fist conditions. Our results suggest that unclenched fist and clenched fist conditions cause reductions in the MNCSA, D1, and D2. More importantly, unclenched fist and clenched fist conditions at 30°wrist flexion and 30°wrist extension can lead to further deformation of the median nerve. PMID:27688983

  2. Shear Strain and Motion of the Subsynovial Connective Tissue and Median Nerve During Single Digit Motion

    PubMed Central

    Yoshii, Yuichi; Zhao, Chunfeng; Henderson, Jacqueline; Zhao, Kristin D.; An, Kai-Nan; Amadio, Peter C.

    2010-01-01

    Purpose The objective of this study was to measure the relative motion of the middle finger flexor digitorum superficialis tendon, its adjacent subsynovial connective tissue, and the median nerve during single digit motion within the carpal tunnel in human cadaver specimens, and estimate the relative motions of these structures in different wrist positions. Methods Using fluoroscopy during simulated single digit flexion, we measured the relative motion of the middle finger flexor digitorum superficialis (FDS) tendon, subsynovial connective tissue and median nerve within the carpal tunnel in twelve human cadavers. Measurements were obtained for three wrist positions: neutral; 60 degrees flexion; and 60 degrees extension. After testing with an intact carpal tunnel was completed, the flexor retinaculum was cut with a scalpel and the same testing procedure was repeated for each wrist position. The relative motions of the tendon, subsynovial connective tissue and median nerve were compared using a shear index, defined as the ratio of the difference in motion along the direction of tendon excursion between two tissues divided by tendon excursion, expressed as a percentage. Results Both tendon-subsynovial connective tissue and tendon-nerve shear index were significantly higher in the 60 degrees of wrist flexion and extension positions, compared to the neutral position. After division of the flexor retinaculum, the shear index in the 60 degrees of wrist extension position remained significantly different, compared to the neutral position. Conclusions In summary, we have found that the relative motion between a tendon and subsynovial connective tissue in the carpal tunnel is maximal at extremes of wrist motion. These positions may predispose the subsynovial connective tissue to shear injury. PMID:19121732

  3. Inadvertent Harvest of the Median Nerve Instead of the Palmaris Longus Tendon.

    PubMed

    Leslie, Bruce M; Osterman, A Lee; Wolfe, Scott W

    2017-07-19

    The palmaris longus tendon is frequently used as a tendon graft or ligament replacement. In rare instances the median nerve has been inadvertently harvested instead of the palmaris longus for use as a tendon. Nineteen cases in which the median nerve had been mistakenly harvested instead of the palmaris longus tendon were collected from members of the American Society for Surgery of the Hand (ASSH) Listserve. Surgeons involved in the subsequent care of the subject who had had an inadvertent harvest were contacted or the chart was reviewed. The reason for the initial procedure, the skill level of the primary surgeon, and when the inadvertent harvest was recognized were documented. When possible, the method of harvest and subsequent treatment were also documented. The most common initial procedure was a reconstruction of the elbow ulnar collateral ligament, followed by basal joint arthroplasty, tendon reconstruction, and reconstruction of the ulnar collateral ligament of the thumb metacarpophalangeal joint. Only 7 of the inadvertent harvests were recognized intraoperatively; in the remaining 12 cases the nerve was used as a tendon graft. The sensory loss was not recognized as being due to the inadvertent harvest until the first postoperative visit (2 subjects), 3 to 4 weeks (2 subjects), 2 to 3 months (2 subjects), 5 to 7 months (2 subjects), 1 year (1 subject), 3 years (1 subject), or 10 years (1 subject). Preoperative clinical identification of the presence or absence of a palmaris longus did not necessarily prevent an inadvertent harvest. Knowledge of the relevant anatomy is crucial to avoiding inadvertent harvest of the median nerve instead of the palmaris longus tendon.

  4. Median nerve stimulation reduces ventricular arrhythmias induced by dorsomedial hypothalamic stimulation.

    PubMed

    Zhao, Shuang; Tang, Min; Yuan, Kexin; Gu, Jingli; Yu, Jun; Long, Xiaoyang; Liu, Miaomiao; Cao, Ji-Min; Zhang, Shu

    2016-12-01

    This study tested the hypothesis that median nerve stimulation (MNS) prevents ventricular arrhythmias (VAs) induced by dorsomedial hypothalamus stimulation (DMHS) and investigated the electrophysiological mechanisms underlying the anti-arrhythmic effects of MNS by recording left stellate ganglion activity (LSGA). Eighteen rabbits were anesthetized, the median nerve was anchored by stimulating electrodes, and a bipolar electrode was implanted into the LSG to record nerve activity. The DMH was stimulated to induce arrhythmia. All animals underwent six repetitions of DMHS (30 s). The 18 rabbits were divided into the following 3 groups: a control group, which underwent only DMHS (n = 6); an MNS group, which underwent MNS during both the third and fourth DMHS repetitions (n = 6); and an LSGA-recording group, for which LSGA was recorded at baseline, immediately following DMHS and again immediately following MNS and DMHS (n = 6). Repeated DMHS-induced multiple VAs, in the rabbits. Compared with the DMHS-only group, the concurrent administration of MNS during DMHS significantly reduced the incidence of VAs (7 ± 3 and 9 ± 2 beats for the third and fourth DMHS + MNS repetitions vs. 29 ± 8 and 27 ± 9 beats for the first two DMHS repetitions, p < 0.05). The total duration of the abnormal discharges of the LSG (ADLSG) following MNS and DMHS was significantly reduced compared with that of the DMHS-only group (40 ± 18 vs. 14 ± 6 s, p < 0.05). MNS reduced VAs induced by DMHS, which is thought to be mediated through suppressing of ADLSG. Median nerve electrical stimulation prevented ventricular arrhythmias induced by DMHS through the mechanism of suppressing abnormal discharges of left stellate ganglion.

  5. Enhancement of median nerve regeneration by mesenchymal stem cells engraftment in an absorbable conduit: improvement of peripheral nerve morphology with enlargement of somatosensory cortical representation

    PubMed Central

    Oliveira, Julia T.; Bittencourt-Navarrete, Ruben Ernesto; de Almeida, Fernanda M.; Tonda-Turo, Chiara; Martinez, Ana Maria B.; Franca, João G.

    2014-01-01

    We studied the morphology and the cortical representation of the median nerve (MN), 10 weeks after a transection immediately followed by treatment with tubulization using a polycaprolactone (PCL) conduit with or without bone marrow-derived mesenchymal stem cell (MSC) transplant. In order to characterize the cutaneous representation of MN inputs in primary somatosensory cortex (S1), electrophysiological cortical mapping of the somatosensory representation of the forepaw and adjacent body parts was performed after acute lesion of all brachial plexus nerves, except for the MN. This was performed in ten adult male Wistar rats randomly assigned in three groups: MN Intact (n = 4), PCL-Only (n = 3), and PCL+MSC (n = 3). Ten weeks before mapping procedures in animals from PCL-Only and PCL+MSC groups, animal were subjected to MN transection with removal of a 4-mm-long segment, immediately followed by suturing a PCL conduit to the nerve stumps with (PCL+MSC group) or without (PCL-Only group) injection of MSC into the conduit. After mapping the representation of the MN in S1, animals had a segment of the regenerated nerve processed for light and transmission electron microscopy. For histomorphometric analysis of the nerve segment, sample size was increased to five animals per experimental group. The PCL+MSC group presented a higher number of myelinated fibers and a larger cortical representation of MN inputs in S1 (3,383 ± 390 fibers; 2.3 mm2, respectively) than the PCL-Only group (2,226 ± 575 fibers; 1.6 mm2). In conclusion, MSC-based therapy associated with PCL conduits can improve MN regeneration. This treatment seems to rescue the nerve representation in S1, thus minimizing the stabilization of new representations of adjacent body parts in regions previously responsive to the MN. PMID:25360086

  6. Enhancement of median nerve regeneration by mesenchymal stem cells engraftment in an absorbable conduit: improvement of peripheral nerve morphology with enlargement of somatosensory cortical representation.

    PubMed

    Oliveira, Julia T; Bittencourt-Navarrete, Ruben Ernesto; de Almeida, Fernanda M; Tonda-Turo, Chiara; Martinez, Ana Maria B; Franca, João G

    2014-01-01

    We studied the morphology and the cortical representation of the median nerve (MN), 10 weeks after a transection immediately followed by treatment with tubulization using a polycaprolactone (PCL) conduit with or without bone marrow-derived mesenchymal stem cell (MSC) transplant. In order to characterize the cutaneous representation of MN inputs in primary somatosensory cortex (S1), electrophysiological cortical mapping of the somatosensory representation of the forepaw and adjacent body parts was performed after acute lesion of all brachial plexus nerves, except for the MN. This was performed in ten adult male Wistar rats randomly assigned in three groups: MN Intact (n = 4), PCL-Only (n = 3), and PCL+MSC (n = 3). Ten weeks before mapping procedures in animals from PCL-Only and PCL+MSC groups, animal were subjected to MN transection with removal of a 4-mm-long segment, immediately followed by suturing a PCL conduit to the nerve stumps with (PCL+MSC group) or without (PCL-Only group) injection of MSC into the conduit. After mapping the representation of the MN in S1, animals had a segment of the regenerated nerve processed for light and transmission electron microscopy. For histomorphometric analysis of the nerve segment, sample size was increased to five animals per experimental group. The PCL+MSC group presented a higher number of myelinated fibers and a larger cortical representation of MN inputs in S1 (3,383 ± 390 fibers; 2.3 mm(2), respectively) than the PCL-Only group (2,226 ± 575 fibers; 1.6 mm(2)). In conclusion, MSC-based therapy associated with PCL conduits can improve MN regeneration. This treatment seems to rescue the nerve representation in S1, thus minimizing the stabilization of new representations of adjacent body parts in regions previously responsive to the MN.

  7. Cortical characterization and inter-dipole distance between unilateral median versus ulnar nerve stimulation of both hands in MEG.

    PubMed

    Theuvenet, Peter J; van Dijk, Bob W; Peters, Maria J; van Ree, Jan M; Lopes da Silva, Fernando L; Chen, Andrew C N

    2006-01-01

    Contralateral somatosensory evoked fields (SEF) by whole head MEG after unilateral median and ulnar nerve stimulation of both hands were studied in 10 healthy right-handed subjects. Major parameters describing cortical activity were examined to discriminate median and ulnar nerve evoked responses. Somatic sensitivity showed high similarity in the 4 study conditions for both hand and nerve. The brain SEFs consisted of 7-8 major peak stages with consistent responses in all subjects at M20, M30, M70 and M90. Comparable inter-hemispheric waveform profile but high inter-subject variability was found. Median nerve induced significantly shorter latencies in the early activities than those of the ulnar nerve. The 3D cortical maps in the post stimulus 450 ms timeframe showed for both nerves two polarity reversals, an early and a late one which is a new finding. Dipole characteristics showed differential sites for the M20 and M30 in the respective nerve. Higher dipole moments evoked by the median nerve were noticed when compared to the ulnar. Furthermore, the results of the dipole distances between both nerves for M20 were calculated to be at 11.17 mm +/- 4.93 (LH) and 16.73 mm +/- 5.66 (RH), respectively after right hand versus left hand stimulation. This study showed substantial differences in the cortical responses between median and ulnar nerve. Especially the dipole distance between median and ulnar nerve on the cortex was computed accurately for the first time in MEG. Little is known however of the cortical responses in chronic pain patients and the parameter(s) that may change in an individual patient or a group. These results provide precise basis for further evaluating cortical changes in functional disorders and disease sequelae related to median and ulnar nerves.

  8. Reliability of a digital electroneurometer for the determination of motor latency of the median nerve.

    PubMed

    Cook, T M; Rosecrance, J C; Brokman, S J; Rulon, A S; Wise, C A

    1991-06-01

    Measurement of distal motor latencies of the median nerve are often part of electrodiagnostic studies used to verify a diagnosis of peripheral neuropathy. Since electrodiagnostic studies are time consuming, expensive, and impractical for large-scale screening of at-risk individuals, a portable digital electroneurometer was developed for measuring motor latencies as a screening tool for early detection of nerve compression syndromes, including carpal tunnel syndrome. The purpose of this study was to determine the intertester and intratester reliability of a digital electroneurometer in subjects with (n=12) and without (n=20) clinical signs of carpal tunnel syndrome. This study addressed only the reliability and not the validity of this device. Using a repeated measures design, three evaluators performed two distal motor latency tests on the median nerve of each of the subjects. Pearson product-moment correlations for intratester reliability ranged from 0.94 to 0.99, and the intraclass correlation coefficient for intertester reliability was 0.96. Two examiners obtained statistically larger latency values on the second test, although these differences are judged to be clinically insignificant. Use of an electroneurometer may expand motor latency testing to a wider variety of settings.

  9. Effect of median-nerve electrical stimulation on BOLD activity in acute ischemic stroke patients.

    PubMed

    Manganotti, P; Storti, S F; Formaggio, E; Acler, M; Zoccatelli, G; Pizzini, F B; Alessandrini, F; Bertoldo, A; Toffolo, G M; Bovi, P; Beltramello, A; Moretto, G; Fiaschi, A

    2012-01-01

    To investigate blood oxygenation level-dependent (BOLD) activation during somatosensory electrical stimulation of the median nerve in acute stroke patients and to determine its correlation with ischemic damage and clinical recovery over time. Fourteen acute stroke patients underwent functional magnetic resonance imaging (fMRI) during contralesional median-nerve electrical stimulation 12-48 h after stroke. Findings were then validated by diffusion tensor imaging (DTI) and motor evoked potential by transcranial magnetic stimulation (TMS). Poor clinical recovery at three months was noted in four patients with no activation in the early days after stroke, whereas good clinical recovery was observed in eight patients with a normal activation pattern in the primary sensory motor area in the acute phase. In two patients BOLD activation correlated weakly with clinical recovery. Findings from TMS and DTI partially correlated with clinical recovery and functional scores. Clinically relevant insights into the "functional reserve" of stroke patients gained with peripheral nerve stimulation during fMRI may carry prognostic value already in the acute period of a cerebrovascular accident. BOLD activation maps could provide insights into the functional organization of the residual systems and could contribute to medical decision making in neurological and rehabilitative treatment. Copyright © 2011 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  10. Current threshold for nerve stimulation depends on electrical impedance of the tissue: a study of ultrasound-guided electrical nerve stimulation of the median nerve.

    PubMed

    Sauter, Axel R; Dodgson, Michael S; Kalvøy, Håvard; Grimnes, Sverre; Stubhaug, Audun; Klaastad, Oivind

    2009-04-01

    Understanding the mechanisms causing variation in current thresholds for electrical nerve stimulation may improve the safety and success rate of peripheral nerve blocks. Electrical impedance of the tissue surrounding a nerve may affect the response to nerve stimulation. In this volunteer study, we investigated the relationship between impedance and current threshold needed to obtain a neuromuscular response. Electrical nerve stimulation and impedance measurements were performed for the median nerve in the axilla and at the elbow in 29 volunteers. The needletip was positioned at a distance of 5, 2.5, and 0 mm from the nerve as judged by ultrasound. Impulse widths of 0.1 and 0.3 ms were used for nerve stimulation. A significant inverse relationship between impedance and current threshold was found at the elbow, at nerve-to-needle distances of 5 and 2.5 mm (P = 0.001 and P = 0.036). Impedance values were significantly lower in the axilla (mean 21.1, sd 9.7 kohm) than at the elbow (mean 36.6, sd 13.4 kohm) (P < 0.001). Conversely, current thresholds for nerve stimulation were significantly higher in the axilla than at the elbow (P < 0.001, P < 0.001, P = 0.024). A mean ratio of 1.82 was found for the measurements of current thresholds with 0.1 versus 0.3 ms impulse duration. Our results demonstrate an inverse relationship between impedance measurements and current thresholds and suggest that current settings used for nerve stimulation may require adjustment based on the tissue type. Further studies should be performed to investigate the clinical impact of our findings.

  11. A fluid-immersed multi-body contact finite element formulation for median nerve stress in the carpal tunnel.

    PubMed

    Ko, Cheolwoong; Brown, Thomas D

    2007-10-01

    Carpal tunnel syndrome (CTS) is among the most important of the family of musculoskeletal disorders caused by chronic peripheral nerve compression. Despite the large body of research in many disciplinary areas aimed at reducing CTS incidence and/or severity, means for objective characterization of the biomechanical insult directly responsible for the disorder have received little attention. In this research, anatomical image-based human carpal tunnel finite element (FE) models were constructed to enable study of median nerve mechanical insult. The formulation included large-deformation multi-body contact between the nerve, the nine digital flexor tendons, and the carpal tunnel boundary. These contact engagements were addressed simultaneously with nerve and tendon fluid-structural interaction (FSI) with the synovial fluid within the carpal tunnel. The effects of pertinent physical parameters on median nerve stress were explored. The results suggest that median nerve stresses due to direct structural contact are typically far higher than those from fluid pressure.

  12. Schwannoma of the median nerve mimicking carpal tunnel syndrome in a pregnant patient. Case report.

    PubMed

    Giasna, Giokits-Kakavouli; Micu, Mihaela C; Micu, Romeo

    2016-12-05

    In patients with symptoms of a peripheral neuropathy especially during pregnancy, use of imaging techniques such as Ultrasound (US) and Magnetic Resonance Imaging (MRI) may be essential for the diagnostic accomplishment. A 30-weekspregnant diabetic female attending US evaluation due to intermittent hand pain, numbness, and weakness bilaterally. Although, the US evaluation revealed the median nerve (MN) normal size, echogenicity and echo-texture within the right carpal tunnel; the US assessment applied proximally to the carpal tunnel, revealed a hypoechoic tumor-like mass and increased MN cross section area. In transverse view, the MN was detected as an eccentric, hypoechoic structure compressed by the aforementioned mass. A presence of MN schwannoma or neurofibroma was suspected. US has been proved to be extremely useful to determine location, extent as well as the type of nerve lesion.

  13. [Median nerve constrictive operation combined with tendon transfer to treat brain paralysis convulsive deformity of hand].

    PubMed

    Ma, Shanjun; Zhou, Tianjian

    2014-05-01

    To evaluate the effectiveness of the median nerve constrictive operation combined with tendon transfer to treat the brain paralysis convulsive deformity of the hand. The clinical data from 21 cases with brain paralysis convulsive deformity of the hand were analyzed retrospectively between August 2009 and April 2012. Of them, there were 13 males and 8 females with an average age of 15 years (range, 10-29 years). The causes of the convulsive cerebral palsy included preterm deliveries in 11 cases, hypoxia asphyxia in 7, traumatic brain injury in 2, and encephalitis sequela in 1. The disease duration was 2-26 years (mean, 10.6 years). All the 21 patients had cock waists, crooking fingers, and contracture of adductors pollicis, 12 had the forearm pronation deformity. According to Ashworth criteria, there were 2 cases at level I, 5 cases at level II, 8 cases at level III, 4 cases at level IV, and 2 cases at level V. All patients had no intelligence disturbances. The forearm X-ray film showed no bone architectural changes before operation. The contraction of muscle and innervation was analyzed before operation. The median nerve constrictive operation combined with tendon transfer was performed. The functional activities and deformity improvement were evaluated during follow-up. After operation, all the patients' incision healed by first intension, without muscle atrophy and ischemic spasm. All the 21 cases were followed up 1.5-4.5 years (mean, 2.3 years). No superficial sensory loss occurred. The effectiveness was excellent in 13 cases, good in 6 cases, and poor in 2 cases, with an excellent and good rate of 90.4% at last follow-up. The median nerve constrictive operation combined with tendon transfer to treat brain paralysis convulsive deformity of the hand can remove and prevent the recurrence of spasm, achieve the orthopedic goals, to assure the restoration of motor function and the improvement of the life quality.

  14. Median Nerve Somatosensory Evoked Potential in HTLV-I Associated Myelopathy

    PubMed Central

    Boostani, Reza; Poorzahed, Ali; Ahmadi, Zahra; Mellat, Ali

    2016-01-01

    Introduction HTLV-I Associated Myelopathy/Tropical Spastic Paraparesis (HAM/TSP) is a progressive Myelopathy that mainly involves the corticospinal tract. Despite pronounced involvement of the lower limbs, patients also have abnormalities in their upper limbs. So, we studied somatosensory-evoked potentials (SSEPs) of the median nerve in HAM/TSP patients to determine the extent of the involvement of the pathway of the central nervous system, especially the cervical spinal cord. Methods In this cross sectional study, 48 patients with HAM/TSP who were referred to Qaem Hospital in Mashhad from October 2010 to October 2011 were evaluated for various indices, including SSEPs of the median nerve for N9, N11, N13, and N20 waveforms and also N11–13 and N13–20 Inter Peak Latency (IPL), severity of disease (based on Osama criteria), disease duration (less or more than 2 years), age, and gender. SPSS software was used for data analysis. The t-test was used for quantitative data, and the chi-squared test was used for the qualitative variables. Results Thirty-four patients (70.2%) were females. The mean age was 45.6 ± 14.2 years. About SSEPs indices of the median nerve, N9 and N11 were normal in all patients, but N13 (50%), N20 (16.7%), IPL11–13 (58.3%), and IPL13–20 (22.9%) were abnormal. No significant relationships were found between age, gender, disease duration, and SSEPs indices (p > 0.05), but IPL11–13 and IPL13–20 had significant relationships with disease disability (p = 0.017 and p = 0.01, respectively). Conclusion Despite the lack of obvious complaints of upper limbs, SSEPs indices of the median nerve from the cervical spinal cord to the cortex were abnormal, which indicated extension of the lesion from the thoracic spinal cord up to the cervical spinal cord and thalamocortical pathways. Also, abnormalities in the cervical spinal cord had a direct correlation with the severity of disability in patients with HAM/TSP. PMID:27382445

  15. In-continuity neuroma of the median nerve after surgical release for carpal tunnel syndrome: case report.

    PubMed

    Depaoli, R; Coscia, D R; Alessandrino, F

    2015-03-01

    Iatrogenic injuries of the median nerve after surgical release for carpal tunnel syndrome resulting in the formation of a neuroma are rare. We present here the case of two patients, one with a bifid median nerve, showing in-continuity neuroma after surgical release for carpal tunnel syndrome. The patients reported persistent post-operative pain and showing symptoms. In both cases, ultrasound showed an in-continuity neuroma with a hypoechoic and enlarged median nerve at the carpal tunnel. The case report shows that ultrasound may be helpful in confirming the clinical diagnosis of neuroma and it is useful for evaluation of the percentage of the area affected by the tear.

  16. Median nerve T2 assessment in the wrist joints: preliminary study in patients with carpal tunnel syndrome and healthy volunteers.

    PubMed

    Cha, Jang Gyu; Han, Jong Kyu; Im, Soo Bin; Kang, Sung Jin

    2014-10-01

    To perform a prospective quantitative analysis of median nerve T2 values and cross-sectional area (CSA) in patients with carpal tunnel syndrome (CTS) as compared to asymptomatic volunteers. Twelve CTS patients with positive nerve conduction results and 12 healthy volunteers (controls) were enrolled and underwent axial T2 mapping of the wrist joints. Median nerve T2 values and CSAs at the distal radioulnar joint, pisiform, and hook of hamate levels were compared between the groups. The T2 values at the proximal and distal carpal tunnel were higher in the CTS patients than in the controls (P < 0.05). The T2 values at the distal radioulnar joint did not differ between the groups (P = 0.99). The CSAs of the median nerve at all levels of the carpal tunnel were significantly larger in the CTS patients than in the controls (P < 0.05). In conclusion, our study demonstrated that median nerve T2 assessment is feasible and that T2 assessment may offer functional information about the median nerve in the carpal tunnel and has the potential to be a promising complementary method for evaluation of CTS patients. A future study with larger sample sizes is necessary to investigate the potential effect of median nerve T2 assessment to a reliable tool in the diagnosis of CTS. © 2013 Wiley Periodicals, Inc.

  17. The cholesterol levels in median nerve and post-mortem interval evaluation.

    PubMed

    Vacchiano, G; Maldonado, A Luna; Ros, M Matas; Di Lorenzo, P; Pieri, M

    2016-08-01

    Cholesterol levels in the median nerve were studied at various post-mortem intervals (PMIs). Single median nerve samples were collected from the wrists of 36 subjects during forensic autopsies of subjects with known circumstances and times of death. Although the absolute values varied, increments in cholesterol concentration were recorded. Subsequently, 16 subjects who did not suffer of any neurological and/or metabolic diseases with known times and circumstances of death were enrolled. For each enrolled subject, two samples were collected from the wrist at an interval of approximately two hours (t1 and t2). The obtained results revealed a gradual increase in cholesterol level with increasing time since death. The cholesterol concentration data obtained for each subject at t1 and t2 were correlated with the time since death, a linear interpolation was applied, and the PMI was back-calculated. Similar trends were obtained for the samples collected at similar PMIs; thus, three groups were considered: PMI<48h, 4878h. Good correlation coefficients were obtained, especially for the first group (R(2)=0.9362) for which the PMI could be calculated with an error that ranged from -4 to 5.9h. Although it requires further confirmation via analyses of larger numbers of samples, the method proposed here can currently be applied to PMI determinations. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  18. [Developmental study of somatosensory evoked potentials in the median nerve in children].

    PubMed

    Lehovský, M; Hotová, Z; Kraus, J

    1990-05-01

    By evaluation of the findings in 134 healthy children aged one month to 14 years the authors obtained normal values of SEP of the median nerve and investigated developmental changes which involved among others an increased rate of conduction along the fibres of the peripheral neuron and changes of the distance between electrodes. From the findings ensued that the conduction velocity in mixed fibres of the median nerve in the portion wrist- Erb's point increased most in children aged 2-4 years where it increased to as much as 10 ms-1, while at the age of 1 month to 2 years the increase was 6 ms-1. This difference can be explained by a different maturity of fibres transmitting the impulses. The great scatter in the youngest children confirmed this view. The latency of the cortical response (N 18) in the youngest children was longest and declined gradually. At the age of 2-4 years it was even lower than in older children which may be explained by a more rapid transmission of the impulse in this age group than was the increment of distances between electrodes. Later, on the other hand, the growth of the extremities was more manifested. The above changes were less apparent in latencies of the spinal wave (N 13) and in values of the central conduction time where some part may have been played also by the relative maturity of structures of the brain stem.

  19. Acute effects of neural mobilization and infrared on the mechanics of the median nerve

    PubMed Central

    Nunes, Monara Kedma; Fontenele dos Santos, Gabrielly; Martins e Silva, Diandra Caroline; Mota de Freitas, Ana Cláudia; Henriques, Isadora Ferreira; Andrade, Peterson Marco; Machado, Dionis de Castro; Teixeira, Silmar; Neves, Marco Orsini; Dias, Gildário; Silva-Júnior, Fernando; Bastos, Victor Hugo

    2016-01-01

    [Purpose] This study analyzed the acute effects of infrared and neural mobilization on the median nerve on the range of elbow extension of the dominant limb. [Subjects and Methods] Forty participants from university, neurologically asymptomatic, 12 males and 28 females (22.8 ± 1.9 years), were randomly divided into four groups: Group 1 (control) rested for 25 minutes in the supine position; Group 2 received the specific neural mobilization for the median nerve; Group 3 received an application of infrared for 15 minutes on the forearm; Group 4 received the same application of infrared followed by neural mobilization. The goniometric parameters of elbow extension were evaluated after the intervention. [Results] Significant differences of extension value were observed between Group 1 and Group 3 (15.75 degrees), and between Group 1 and Group 4 (14.60 degrees), and the average higher in Group 3 (26.35 degrees). [Conclusion] This research provides new experimental evidence that NM in relation to superficial heat produces an immediate effect on elbow range of motion versus NM isolated. PMID:27390402

  20. Acute effects of neural mobilization and infrared on the mechanics of the median nerve.

    PubMed

    Nunes, Monara Kedma; Fontenele Dos Santos, Gabrielly; Martins E Silva, Diandra Caroline; Mota de Freitas, Ana Cláudia; Henriques, Isadora Ferreira; Andrade, Peterson Marco; Machado, Dionis de Castro; Teixeira, Silmar; Neves, Marco Orsini; Dias, Gildário; Silva-Júnior, Fernando; Bastos, Victor Hugo

    2016-06-01

    [Purpose] This study analyzed the acute effects of infrared and neural mobilization on the median nerve on the range of elbow extension of the dominant limb. [Subjects and Methods] Forty participants from university, neurologically asymptomatic, 12 males and 28 females (22.8 ± 1.9 years), were randomly divided into four groups: Group 1 (control) rested for 25 minutes in the supine position; Group 2 received the specific neural mobilization for the median nerve; Group 3 received an application of infrared for 15 minutes on the forearm; Group 4 received the same application of infrared followed by neural mobilization. The goniometric parameters of elbow extension were evaluated after the intervention. [Results] Significant differences of extension value were observed between Group 1 and Group 3 (15.75 degrees), and between Group 1 and Group 4 (14.60 degrees), and the average higher in Group 3 (26.35 degrees). [Conclusion] This research provides new experimental evidence that NM in relation to superficial heat produces an immediate effect on elbow range of motion versus NM isolated.

  1. Ultrasound-guided hydrodissection decreases gliding resistance of the median nerve within the carpal tunnel.

    PubMed

    Evers, Stefanie; Thoreson, Andrew R; Smith, Jay; Zhao, Chunfeng; Geske, Jennifer R; Amadio, Peter C

    2017-06-16

    The aim of this study was to assess alterations in median nerve (MN) biomechanics within the carpal tunnel resulting from ultrasound-guided hydrodissection in a cadaveric model. Twelve fresh frozen human cadaver hands were used. MN gliding resistance was measured at baseline and posthydrodissection, by pulling the nerve proximally and then returning it to the origin. Six specimens were treated with hydrodissection, and 6 were used as controls. In the hydrodissection group there was a significant reduction in mean peak gliding resistance of 92.9 ± 34.8 mN between baseline and immediately posthydrodissection (21.4% ± 10.5%; P = 0.001). No significant reduction between baseline and the second cycle occurred in the control group: 9.6 ± 29.8 mN (0.4% ± 5.3%; P = 0.467). Hydrodissection can decrease the gliding resistance of the MN within the carpal tunnel, at least in wrists unaffected by carpal tunnel syndrome. A clinical trial of hydrodissection seems justified. Muscle Nerve, 2017. © 2017 Wiley Periodicals, Inc.

  2. Accuracy of in-office nerve conduction studies for median neuropathy: a meta-analysis.

    PubMed

    Strickland, James W; Gozani, Shai N

    2011-01-01

    Carpal tunnel syndrome is the most common focal neuropathy. It is typically diagnosed clinically and confirmed by abnormal median nerve conduction across the wrist (median neuropathy [MN]). In-office nerve conduction testing devices facilitate performance of nerve conduction studies (NCS) and are used by hand surgeons in the evaluation of patients with upper extremity symptoms. The purpose of this meta-analysis was to determine the diagnostic accuracy of this testing method for MN in symptomatic patients. We searched the MEDLINE database for prospective cohort studies that evaluated the diagnostic accuracy of in-office NCS for MN in symptomatic patients with traditional electrodiagnostic laboratories as reference standards. We assessed included studies for quality and heterogeneity in diagnostic performance and determined pooled statistical outcome measures when appropriate. We identified 5 studies with a total of 448 symptomatic hands. The pooled sensitivity and specificity were 0.88 (95% confidence interval [CI], 0.83-0.91) and 0.93 (95% CI, 0.88-0.96), respectively. Specificities exhibited heterogeneity. The diagnostic odds ratios were homogeneous, with a pooled value of 62.0 (95% CI, 30.1-127). This meta-analysis showed that in-office NCS detects MN with clinically relevant accuracy. Performance was similar to interexaminer agreement for MN within a traditional electrodiagnostic laboratory. There was some variation in diagnostic operating characteristics. Therefore, physicians using this technology should interpret test results within a clinical context and with attention to the pretest probability of MN, rather than in absolute terms. Copyright © 2011 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  3. A Human Hair Keratin Hydrogel Scaffold Enhances Median Nerve Regeneration in Nonhuman Primates: An Electrophysiological and Histological Study

    PubMed Central

    Pace, Lauren A.; Plate, Johannes F.; Mannava, Sandeep; Barnwell, Jonathan C.; Koman, L. Andrew; Li, Zhongyu; Smith, Thomas L.

    2014-01-01

    A human hair keratin biomaterial hydrogel scaffold was evaluated as a nerve conduit luminal filler following median nerve transection injury in 10 Macaca fascicularis nonhuman primates (NHP). A 1 cm nerve gap was grafted with a NeuraGen® collagen conduit filled with either saline or keratin hydrogel and nerve regeneration was evaluated by electrophysiology for a period of 12 months. The keratin hydrogel-grafted nerves showed significant improvement in return of compound motor action potential (CMAP) latency and recovery of baseline nerve conduction velocity (NCV) compared with the saline-treated nerves. Histological evaluation was performed on retrieved median nerves and abductor pollicis brevis (APB) muscles at 12 months. Nerve histomorphometry showed a significantly larger nerve area in the keratin group compared with the saline group and the keratin APB muscles had a significantly higher myofiber density than the saline group. This is the first published study to show that an acellular biomaterial hydrogel conduit filler can be used to enhance peripheral nerve regeneration and motor recovery in an NHP model. PMID:24083825

  4. A human hair keratin hydrogel scaffold enhances median nerve regeneration in nonhuman primates: an electrophysiological and histological study.

    PubMed

    Pace, Lauren A; Plate, Johannes F; Mannava, Sandeep; Barnwell, Jonathan C; Koman, L Andrew; Li, Zhongyu; Smith, Thomas L; Van Dyke, Mark

    2014-02-01

    A human hair keratin biomaterial hydrogel scaffold was evaluated as a nerve conduit luminal filler following median nerve transection injury in 10 Macaca fascicularis nonhuman primates (NHP). A 1 cm nerve gap was grafted with a NeuraGen® collagen conduit filled with either saline or keratin hydrogel and nerve regeneration was evaluated by electrophysiology for a period of 12 months. The keratin hydrogel-grafted nerves showed significant improvement in return of compound motor action potential (CMAP) latency and recovery of baseline nerve conduction velocity (NCV) compared with the saline-treated nerves. Histological evaluation was performed on retrieved median nerves and abductor pollicis brevis (APB) muscles at 12 months. Nerve histomorphometry showed a significantly larger nerve area in the keratin group compared with the saline group and the keratin APB muscles had a significantly higher myofiber density than the saline group. This is the first published study to show that an acellular biomaterial hydrogel conduit filler can be used to enhance peripheral nerve regeneration and motor recovery in an NHP model.

  5. A study of median nerve entrapment neuropathy at wrist in uremic patients.

    PubMed

    Shende, V S; Sharma, R D; Pawar, S M; Waghmare, S N

    2015-01-01

    Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy seen in uremic patients. The study was undertaken to estimate the frequency of CTS in uremic patients and to identify the most sensitive electrodiagnostic test. Study was conducted on 80 subjects of age 30-60 years. End-stage kidney disease patients were recruited for the clinical evaluation, motor nerve conduction studies (NCS), sensory NCS, F wave study and median-versus-ulnar comparison studies (palm-to-wrist mixed comparison study, digit 4 sensory latencies study and lumbrical-interossei comparison study). Among three different diagnostic modalities, frequency of CTS was found to be 17.5% with clinical evaluation, 15% with routine NCS studies and 25% with median-versus-ulnar comparison studies. Among the median-versus-ulnar comparison studies, lumbrical-interossei comparison study was found to be most sensitive (90%). The comparative tests for CTS are more sensitive compared to routine NCS and clinical examination. Among the comparative tests, lumbrical-interossei comparison study is the most sensitive. Early diagnosis of CTS may help patients of uremia to seek proper treatment at an appropriate time.

  6. A study of median nerve entrapment neuropathy at wrist in uremic patients

    PubMed Central

    Shende, V. S.; Sharma, R. D.; Pawar, S. M.; Waghmare, S. N.

    2015-01-01

    Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy seen in uremic patients. The study was undertaken to estimate the frequency of CTS in uremic patients and to identify the most sensitive electrodiagnostic test. Study was conducted on 80 subjects of age 30–60 years. End-stage kidney disease patients were recruited for the clinical evaluation, motor nerve conduction studies (NCS), sensory NCS, F wave study and median-versus-ulnar comparison studies (palm-to-wrist mixed comparison study, digit 4 sensory latencies study and lumbrical-interossei comparison study). Among three different diagnostic modalities, frequency of CTS was found to be 17.5% with clinical evaluation, 15% with routine NCS studies and 25% with median-versus-ulnar comparison studies. Among the median-versus-ulnar comparison studies, lumbrical-interossei comparison study was found to be most sensitive (90%). The comparative tests for CTS are more sensitive compared to routine NCS and clinical examination. Among the comparative tests, lumbrical-interossei comparison study is the most sensitive. Early diagnosis of CTS may help patients of uremia to seek proper treatment at an appropriate time. PMID:26199474

  7. Significant CMAP decrement by repetitive nerve stimulation is more frequent in median than ulnar nerves of patients with amyotrophic lateral sclerosis.

    PubMed

    Yamashita, Satoshi; Sakaguchi, Hideya; Mori, Akira; Kimura, En; Maeda, Yasushi; Hirano, Teruyuki; Uchino, Makoto

    2012-03-01

    Several studies have shown a significant amplitude decrement in compound muscle action potentials (CMAPs) on repetitive nerve stimulation (RNS) of muscles involved in amyotrophic lateral sclerosis (ALS). In ALS, muscle wasting preferentially affects the thenar muscles (APB) rather than the hypothenar muscles (ADM). We performed RNS studies in the APB and ADM muscles of 32 ALS patients to determine whether the effect of RNS differs between the median and ulnar nerves. The decremental responses to RNS were greater in the APB than in the ADM. Reduced CMAP amplitude was negatively correlated with CMAP decrement in median but not in ulnar nerves. The greater CMAP decrement in median nerve is attributable to preferential involvement of the APB in the pathophysiology of ALS or some underlying difference in the biology of the two muscles/nerves. Further investigations will better our understanding of the pathophysiology of ALS. Copyright © 2011 Wiley Periodicals, Inc.

  8. Charcot-Marie-Tooth 1A Concurrent with Schwannomas of the Spinal Cord and Median Nerve

    PubMed Central

    Kwon, Joo Young; Chung, Ki Wha; Park, Eun Kyung; Park, Sun Wha

    2009-01-01

    We identified Charcot-Marie-Tooth disease type 1A (CMT1A) in a family with schwannomas in the spinal cord and median nerve. The CMT1A in this family showed an autosomal dominant pattern, like other CMT patients with PMP22 duplication, and the family also indicated a possible genetic predisposition to schwannomas by 'mother-to-son' transmission. CMT1A is mainly caused by duplication of chromosome 17p11.2-p12 (PMP22 gene duplication). A schwannoma is a benign encapsulated tumor originating from a Schwann cell. A case of hereditary neuropathy with liability to pressure palsies (HNPP) concurrent with schwannoma has been previously reported. Although it seems that the co-occurrence of CMT1A and schwannomas in a family would be the result of independent events, we could not completely ignore the possibility that the coincidence of two diseases might be due to a shared genetic background. PMID:19654968

  9. Distribution patterns of the muscular branch of the median nerve in the thenar region.

    PubMed Central

    Olave, E; Prates, J C; Del Sol, M; Sarmento, A; Gabrielli, C

    1995-01-01

    Studies on the distribution patterns of the muscular branch of the median nerve to the thenar muscles are scarce. Available accounts give only general descriptions. To establish the distribution pattern more precisely, we dissected 60 palmar regions from 30 cadavers of adult individuals, ranging in age from 23 to 77 y. The distribution pattern of the muscular branch was classified into 3 types. In 50% of subjects there were branches to the superficial head of flexor pollicis brevis (FPB), abductor pollicis brevis (APB) and opponens pollicis (OP) (type I). In 40% there were branches only to APB and OP (type II). In the remainder (type III) the muscular branch provided independent branches to APB, OP and FPB, to APB and OP, or to APB and FPB, after dividing precociously. Types I and II were further subdivided according to the site, direction and number of the individual branches. Images Fig. 4 Fig. 5 Fig. 6 PMID:7649846

  10. Steady-state activation in somatosensory cortex after changes in stimulus rate during median nerve stimulation.

    PubMed

    Manganotti, Paolo; Formaggio, Emanuela; Storti, Silvia Francesca; Avesani, Mirko; Acler, Michele; Sala, Francesco; Magon, Stefano; Zoccatelli, Giada; Pizzini, Francesca; Alessandrini, Franco; Fiaschi, Antonio; Beltramello, Alberto

    2009-11-01

    Passive electrical stimulation activates various human somatosensory cortical systems including the contralateral primary somatosensory area (SI), bilateral secondary somatosensory area (SII) and bilateral insula. The effect of stimulation frequency on blood oxygenation level-dependent (BOLD) activity remains unclear. We acquired 3-T functional magnetic resonance imaging (fMRI) in eight healthy volunteers during electrical median nerve stimulation at frequencies of 1, 3 and 10 Hz. During stimulation BOLD signal changes showed activation in the contralateral SI, bilateral SII and bilateral insula. Results of fMRI analysis showed that these areas were progressively active with the increase of rate of stimulation. As a major finding, the contralateral SI showed an increase of peak of BOLD activation from 1 to 3 Hz but reached a plateau during 10-Hz stimulation. Our finding is of interest for basic research and for clinical applications in subjects unable to perform cognitive tasks in the fMRI scanner.

  11. Bilobed splitting of median nerve somatosensory evoked p14 potential under deep hypothermia.

    PubMed

    Wagner, Wolfgang

    2002-01-01

    To further elucidate temperature related changes in subcortical components of somatosensory evoked potentials (SEP) in intraoperative monitoring. Intraoperative monitoring of subcortical median nerve SEP under deep hypothermia is described in a patient undergoing intracranial giant aneurysm surgery. The P14 potential was recorded from Fz-Pgz (front to nasopharynx). At a body core temperature of less than 17 degrees C, P14 showed a bilobed splitting that was reversible with rewarming. A comparison with latencies of other subcortical potentials of presynaptic and postsynaptic origin, recorded at the neck, speaks in favor of a presynaptic generation of the first P14 wave and a postsynaptic origin of the latter P14 wave. Deep hypothermia may separate presynaptic and postsynaptic electric activity of evoked potentials that overlap at normal body temperature. Such possible phenomena must be kept in mind to correctly interprete monitoring data at very low body temperatures and may help in better understanding the generation of different SEP components.

  12. A widely displaced Galeazzi-equivalent lesion with median nerve compromise.

    PubMed

    Galanopoulos, Ilias; Fogg, Quentin; Ashwood, Neil; Fu, Katherine

    2012-08-18

    We present the case of a 14-year-old boy with a right distal radial fracture accompanied by a severely displaced complete distal ulnar physeal separation and associated median nerve compromise. This injury is known as Galeazzi-equivalent lesion in children and is an extremely rare injury associated with growth arrest. Recognition of the lesion can be difficult but wide displacement may be associated with other significant injuries such as neurovascular compromise. Prompt intervention reversed the neurological symptoms. At 10-month postoperation there was neither growth arrest nor loss of motion. Complete separation of the ulna physis remains often because of soft tissue interposition or capsule problems and prompt reduction is recommended in the literature as a priority.

  13. A widely displaced Galeazzi-equivalent lesion with median nerve compromise

    PubMed Central

    Galanopoulos, Ilias; Fogg, Quentin; Ashwood, Neil; Fu, Katherine

    2012-01-01

    We present the case of a 14-year-old boy with a right distal radial fracture accompanied by a severely displaced complete distal ulnar physeal separation and associated median nerve compromise. This injury is known as Galeazzi-equivalent lesion in children and is an extremely rare injury associated with growth arrest. Recognition of the lesion can be difficult but wide displacement may be associated with other significant injuries such as neurovascular compromise. Prompt intervention reversed the neurological symptoms. At 10-month postoperation there was neither growth arrest nor loss of motion. Complete separation of the ulna physis remains often because of soft tissue interposition or capsule problems and prompt reduction is recommended in the literature as a priority. PMID:22907852

  14. Ultrasound elastographic evaluation of the median nerve in hemodialysis with carpal tunnel syndrome.

    PubMed

    Xin, Hua; Hu, Hai-Yang; Liu, Bin; Liu, Xiang; Li, Xia; Li, Jie

    2017-01-01

    The aim of this study was to compare the elasticity of the median nerve (MN) between hemodialysis (HD) patients without carpal tunnel syndrome (CTS) and with CTS, and to evaluate the diagnostic usefulness of the elasticity of the MN in HD-CTS. The MN in 22 HD patients without CTS and 49 HD-CTS patients was studied. The cross-sectional area (CSA) and the elasticity of the MN, which was measured as the subcutaneous fat/median nerve (SF/MN) strain ratio, were evaluated. The mean SF/MN strain ratio in the groups that had received hemodialysis for 0-5, >5-10, and >10-15 years was 1.4 ± 0.28, 1.7 ± 0.18, and 2.0 ± 0.67, respectively. The mean CSA of the MN in the three groups was 9.9 ± 1.30, 11.6 ± 1.61, and 13.4 ± 2.14 mm(2), respectively. The presence of CTS was predicted by means of SF/MN strain ratio and CSA cutoff values of 1.8 and 11 mm(2), respectively. Both the SF/MN strain ratio and the CSA in the patients with CTS were higher than those in the patients without CTS (P < 0.05). The sensitivity and specificity of the SF/MN strain ratio and CSA of the MN were 75 and 92 % and 79.2 and 84 %, respectively. Sonoelastography helps to improve the diagnostic accuracy of the ultrasonographic assessment of CTS.

  15. Ultrasound imaging of the median nerve as a prognostic factor for carpal tunnel decompression.

    PubMed

    Bland, Jeremy D P; Rudolfer, Stephan M

    2014-05-01

    The diagnostic value of ultrasound imaging in carpal tunnel syndrome is established, but reports on its prognostic value have been contradictory. This investigation was an observational study of subjective surgical results, evaluated by symptom severity and functional status scales, and an ordinal scale for overall outcome, for 145 carpal tunnel decompressions in relation to preoperative measurement of median nerve cross-sectional area. The surgical success rate was 86%. In univariate analyses no significant correlation existed between outcome and preoperative cross-sectional area, nor with preoperative nerve conduction studies or patient variables, except for body mass index and gender. A multivariate model including electrophysiological, imaging, and patient variables was moderately predictive of success with an area under the receiver operating characteristic curve of 0.82. Cross-sectional area alone is unlikely to be a sufficiently reliable predictor of outcome for use in counseling individual patients, but imaging results may be useful in multivariate prognostic models. Copyright © 2013 Wiley Periodicals, Inc.

  16. Communication between the musculocutaneous and median nerves in the arm: an anatomical study and clinical implications

    PubMed Central

    Ballesteros, Luis Ernesto; Forero, Pedro Luis; Buitrago, Edna Rocío

    2014-01-01

    Objective To determine the frequency and features of communication between the musculocutaneous nerve (MCN) and median nerve (MN) in a sample of the Colombian population, and assess its clinical implication. Methods The arms of 53 cadaver specimens that had been subjected to necropsy at the National Institute of Forensic Medicine, in Bucaramanga, Colombia, were studied. The structures of the anterior compartment of the arm were dissected and characterized regarding the presence of communication between the MCN and MN. Results A communicating branch was found in 21/106 upper limbs (19.8%), occurring bilaterally in 10 (47.6%) and unilaterally in 11 (52.4%), without significant difference regarding the side of occurrence (p = 0.30). In 17% of the cases, there was MCN-MN communication in which the communicating branch was seen leaving the MCN after piercing the coracobrachialis muscle (Type I). In 2.8%, the connection was from the MN to the MCN (Type II). The length of the communicating branch was 57.8 ± 33.4 mm. The distances from the proximal and distal points of this branch to the coracoid process were 138 ± 39.4 mm and 188 ± 48.3 mm, respectively. The communicating branch was located mostly in the middle third of the arm. Conclusions The frequency of MCN-MN communication observed in the present study is in the middle of the range of what was reported in previous studies. MCN-MN connections need to be taken into account in diagnosing and managing peripheral nerve lesions of the upper limbs. PMID:26535190

  17. The influence of wrist posture, grip type, and grip force on median nerve shape and cross-sectional area.

    PubMed

    Cowley, Jeffrey C; Leonardis, Joshua; Lipps, David B; Gates, Deanna H

    2017-05-01

    During grasping, the median nerve undergoes mechanical stress in the carpal tunnel which may contribute to carpal tunnel syndrome. This study investigated the effects of wrist posture, grip type, and grip force on the shape and cross-sectional area of the median nerve. Ultrasound examination was used to obtain cross-sectional images of the dominant wrist of 16 healthy subjects (8 male) at the proximal carpal tunnel during grasping. The cross-sectional area, circularity, and axis lengths of the median nerve were assessed in 27 different conditions (3 postures × 3 grip types × 3 force levels). There were no significant changes in median nerve cross-sectional area (P > 0.05). There were significant interactions across posture, grip type, and grip force affecting nerve circularity and axis lengths. When the wrist was flexed, increasing grip force caused the median nerve to shorten in the mediolateral direction and lengthen in the anteroposterior direction (P < 0.04), becoming more circular. These effects were significant during four finger pinch grip and chuck grip (P < 0.05) but not key grip (P > 0.07). With the wrist extended, the nerve became more flattened (less circular) as grip force increased during four finger pinch grip and chuck grip (P < 0.04) but not key grip (P > 0.3). Circularity was lower during the four finger pinch compared to chuck or key grip (P < 0.03). The findings suggest that grip type and wrist posture significantly alter the shape of the median nerve. Clin. Anat. 30:470-478, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  18. Nerve damage in leprosy: An electrophysiological evaluation of ulnar and median nerves in patients with clinical neural deficits: A pilot study.

    PubMed

    Kar, Sumit; Krishnan, Ajay; Singh, Neha; Singh, Ramji; Pawar, Sachin

    2013-04-01

    Leprosy involves peripheral nerves sooner or later in the course of the disease leading to gross deformities and disabilities. Sadly, by the time it becomes clinically apparent, the nerve damage is already quite advanced. However, if the preclinical damage is detected early in the course of disease, it can be prevented to a large extent. We conducted an electrophysiological pilot study on 10 patients with clinically manifest leprosy, in the Dermatology Department of Mahatma Gandhi Institute of Medical Sciences, Sewagram. This study was done to assess the nerve conduction velocity, amplitude and latency of ulnar and median nerves. We found reduced conduction velocities besides changes in latency and amplitude in the affected nerves. Changes in sensory nerve conduction were more pronounced. Also, sensory latencies and amplitude changes were more severe than motor latencies and amplitude in those presenting with muscle palsies. However, further studies are going on to identify parameters to detect early nerve damage in leprosy.

  19. Transverse Ultrasound Assessment of Median Nerve Deformation and Displacement in the Human Carpal Tunnel during Wrist Movements

    PubMed Central

    Wang, Yuexiang; Zhao, Chunfeng; Passe, Sandra M.; Filius, Anika; Thoreson, Andrew R.; An, Kai-Nan; Amadio, Peter C.

    2013-01-01

    The symptoms of carpal tunnel syndrome, a compression neuropathy of the median nerve at the wrist, are aggravated by wrist motion, but the effect of these motions on median nerve motion are unknown. In order to better understand the biomechanics of the abnormal nerve, it is first necessary to understand normal nerve movement. The purpose of this study was to evaluate the deformation and displacement of the normal median nerve at the proximal carpal tunnel level on transverse ultrasound images during different wrist movements, in order to have a baseline for comparison with abnormal movements. Dynamic ultrasound images were obtained in both wrists of 10 asymptomatic volunteers during wrist maximal flexion, extension and ulnar deviation. In order to simplify the analysis, the initial and final shape and position of the median nerve were measured and analyzed. The circularity of the median nerve was significantly increased and the aspect ratio and perimeter were significantly decreased in the final image compared to that in the first image during wrist flexion with finger extension, wrist flexion with finger flexion and wrist ulnar deviation with finger extension (p<0.01). There were significant differences in median nerve displacement vector between finger flexion, wrist flexion with finger extension and wrist ulnar deviation with finger extension (all p<0.001). The mean amplitudes of the median nerve motion in wrist flexion with finger extension (2.36±0.79 NU), wrist flexion with finger flexion (2.46±0.84 NU) and wrist ulnar deviation with finger extension (2.86±0.51 NU) were higher than those in finger flexion (0.82±0.33 NU), wrist extension with finger extension (0.77±0.46 NU) and wrist extension with finger flexion (0.81±0.58 NU) (p<0.0001). In the normal carpal tunnel, wrist flexion and ulnar deviation could induce significant transverse displacement and deformation of the median nerve. PMID:24210862

  20. Transverse ultrasound assessment of median nerve deformation and displacement in the human carpal tunnel during wrist movements.

    PubMed

    Wang, Yuexiang; Zhao, Chunfeng; Passe, Sandra M; Filius, Anika; Thoreson, Andrew R; An, Kai-Nan; Amadio, Peter C

    2014-01-01

    The symptoms of carpal tunnel syndrome, a compression neuropathy of the median nerve at the wrist, are aggravated by wrist motion, but the effect of these motions on median nerve motion are unknown. To better understand the biomechanics of the abnormal nerve, it is first necessary to understand normal nerve movement. The purpose of this study was to evaluate the deformation and displacement of the normal median nerve at the proximal carpal tunnel level on transverse ultrasound images during different wrist movements, to have a baseline for comparison with abnormal movements. Dynamic ultrasound images of both wrists of 10 asymptomatic volunteers were obtained during wrist maximal flexion, extension and ulnar deviation. To simplify the analysis, the initial and final shape and position of the median nerve were measured and analyzed. The circularity of the median nerve was significantly increased and the aspect ratio and perimeter were significantly decreased in the final image compared with the first image during wrist flexion with finger extension, wrist flexion with finger flexion and wrist ulnar deviation with finger extension (p < 0.01). There were significant differences in median nerve displacement vector between finger flexion, wrist flexion with finger extension and wrist ulnar deviation with finger extension (all p's < 0.001). The mean amplitudes of median nerve motion in wrist flexion with finger extension (2.36 ± 0.79 normalized units [NU]), wrist flexion with finger flexion (2.46 ± 0.84 NU) and wrist ulnar deviation with finger extension (2.86 ± 0.51 NU) were higher than those in finger flexion (0.82 ± 0.33 NU), wrist extension with finger extension (0.77 ± 0.46 NU) and wrist extension with finger flexion (0.81 ± 0.58 NU) (p < 0.0001). In the normal carpal tunnel, wrist flexion and ulnar deviation could induce significant transverse displacement and deformation of the median nerve. Copyright © 2014 World Federation for Ultrasound

  1. A novel classification of musculocutaneous nerve variations: The relationship between the communicating branch and transposed innervation of the brachial flexors to the median nerve.

    PubMed

    Hayashi, Mari; Shionoya, Kento; Hayashi, Shogo; Hatayama, Naoyuki; Kawata, Shinichi; Qu, Ning; Hirai, Shuichi; Miyaso, Hidenobu; Itoh, Masahiro

    2017-01-01

    The musculocutaneous nerve innervates the brachial flexors; i.e., the coracobrachialis, biceps brachii, and brachialis. The musculocutaneous and median nerve sometimes share a communicating branch and also muscular branches to brachial flexors are sometimes transposed to median nerve. Because these variations constitute a potentially important clinical and surgical issue, we evaluated 130 upper limbs of 65 cadavers and 184 cases of musculocutaneous and median nerve variations in the literature and devised a novel system of classification that covers each pattern of variation. Our proposed classification was applicable in all of our cases and those previously reported. In addition, transposed innervation of the brachial flexors from the musculocutaneous nerve to the communicating branches was observed in one limb in our case series. In this case and all previously reported cases of transposed innervation of the brachial flexors, communicating branches between the musculocutaneous and median nerve were found and no brachial flexor branch arose from the musculocutaneous nerve distal to the communicating branches. Consequently, we established that, as per our novel classification, all patterns of communicating branches could be classified into five types and the patterns of transposed innervation of the brachial flexors into three types. Copyright © 2016 Elsevier GmbH. All rights reserved.

  2. Mechanisms responsible for the effect of median nerve electrical stimulation on traumatic brain injury-induced coma: orexin-A-mediated N-methyl-D-aspartate receptor subunit NR1 upregulation

    PubMed Central

    Feng, Zhen; Du, Qing

    2016-01-01

    Electrical stimulation of the median nerve is a noninvasive technique that facilitates awakening from coma. In rats with traumatic brain injury-induced coma, median nerve stimulation markedly enhances prefrontal cortex expression of orexin-A and its receptor, orexin receptor 1. To further understand the mechanism underlying wakefulness mediated by electrical stimulation of the median nerve, we evaluated its effects on the expression of the N-methyl-D-aspartate receptor subunit NR1 in the prefrontal cortex in rat models of traumatic brain injury-induced coma, using immunohistochemistry and western blot assays. In rats with traumatic brain injury, NR1 expression increased with time after injury. Rats that underwent electrical stimulation of the median nerve (30 Hz, 0.5 ms, 1.0 mA for 15 minutes) showed elevated NR1 expression and greater recovery of consciousness than those without stimulation. These effects were reduced by intracerebroventricular injection of the orexin receptor 1 antagonist SB334867. Our results indicate that electrical stimulation of the median nerve promotes recovery from traumatic brain injury-induced coma by increasing prefrontal cortex NR1 expression via an orexin-A-mediated pathway. PMID:27482224

  3. Mechanisms responsible for the effect of median nerve electrical stimulation on traumatic brain injury-induced coma: orexin-A-mediated N-methyl-D-aspartate receptor subunit NR1 upregulation.

    PubMed

    Feng, Zhen; Du, Qing

    2016-06-01

    Electrical stimulation of the median nerve is a noninvasive technique that facilitates awakening from coma. In rats with traumatic brain injury-induced coma, median nerve stimulation markedly enhances prefrontal cortex expression of orexin-A and its receptor, orexin receptor 1. To further understand the mechanism underlying wakefulness mediated by electrical stimulation of the median nerve, we evaluated its effects on the expression of the N-methyl-D-aspartate receptor subunit NR1 in the prefrontal cortex in rat models of traumatic brain injury-induced coma, using immunohistochemistry and western blot assays. In rats with traumatic brain injury, NR1 expression increased with time after injury. Rats that underwent electrical stimulation of the median nerve (30 Hz, 0.5 ms, 1.0 mA for 15 minutes) showed elevated NR1 expression and greater recovery of consciousness than those without stimulation. These effects were reduced by intracerebroventricular injection of the orexin receptor 1 antagonist SB334867. Our results indicate that electrical stimulation of the median nerve promotes recovery from traumatic brain injury-induced coma by increasing prefrontal cortex NR1 expression via an orexin-A-mediated pathway.

  4. Ultrasound assessment of the displacement and deformation of the median nerve in the human carpal tunnel with active finger motion.

    PubMed

    Yoshii, Yuichi; Villarraga, Hector R; Henderson, Jacqueline; Zhao, Chunfeng; An, Kai-Nan; Amadio, Peter C

    2009-12-01

    Peripheral nerves are mobile structures, stretching and translating in response to changes in the position of adjuvant anatomic structures. The objective of this study was to develop a novel method to characterize the relative motion and deformation of the median nerve on cross-sectional ultrasound images of the carpal tunnel during active finger motion. Fifteen volunteers without a history of carpal tunnel syndrome or wrist trauma were recruited. An ultrasound scanner and a linear array transducer were used to evaluate the motion of the median nerve and the flexor tendons within the carpal tunnel during motion from full extension to full flexion by the four fingers (fist motion) and by the long finger alone. The displacement of the median nerve relative to the long-finger flexor digitorum superficialis tendon as well as the perimeter, cross-sectional area, circularity, and aspect ratio of a minimum enclosing rectangle of the median nerve were measured. The data were compared between single-digit motion and fist motion and between extension and flexion positions. The distance between the long-finger flexor digitorum superficialis tendon and the median nerve with isolated long-finger flexion was decreased in the ulnar-radial direction and increased in the palmar-dorsal direction as compared with the distance with four-finger flexion (p < 0.01). Compared with the values with fist motion, the aspect ratio was decreased and the circularity was increased with long-finger motion (p < 0.01). This report presents a method with which to assess displacement and deformation of the median nerve on a cross-sectional ultrasound image during different finger motions. This method may be useful to assess pathological changes within the carpal tunnel, and we plan to perform a similar study of patients with carpal tunnel syndrome on the basis of these preliminary data.

  5. Effect of heat, cold, and pressure on the transverse carpal ligament and median nerve: a pilot study.

    PubMed

    Laymon, Michael; Petrofsky, Jerrold; McKivigan, James; Lee, Haneul; Yim, JongEun

    2015-02-11

    This study quantified the effects of heat, cold, and pressure on the median nerve and transverse carpal ligament in subjects without carpal tunnel syndrome. Subjects were individuals ages 20-50 who had no symptoms of carpal tunnel disease. Imaging ultrasound was used to measure the clearance around the median nerve, transverse ligament elasticity, nerve conduction velocity, thickness of the carpal ligament, and area of the median nerve. Pressure was applied to the carpal ligament to assess the effects of increasing pressure on these structures. On 3 separate days, 10 subjects had ThermaCare heat or cold packs applied, for either 60 or 120 minutes for heat or 20 minutes for cold, to the palmer surface of the hand. Tissue changes were recorded as a response to pressure applied at 0, 5, 10, and 20 N. The size of the nerve and ligaments were not significantly altered by pressure with the hand at room temperature and after cold exposure. After heat, the nerve, ligaments, and tendons showed significantly more elasticity. Application of cold to the hand may reduce compression of the carpal ligament and nerve.

  6. Effect of Heat, Cold, and Pressure on the Transverse Carpal Ligament and Median Nerve: A Pilot Study

    PubMed Central

    Laymon, Michael; Petrofsky, Jerrold; McKivigan, James; Lee, Haneul; Yim, JongEun

    2015-01-01

    Background This study quantified the effects of heat, cold, and pressure on the median nerve and transverse carpal ligament in subjects without carpal tunnel syndrome. Material/Methods Subjects were individuals ages 20–50 who had no symptoms of carpal tunnel disease. Imaging ultrasound was used to measure the clearance around the median nerve, transverse ligament elasticity, nerve conduction velocity, thickness of the carpal ligament, and area of the median nerve. Pressure was applied to the carpal ligament to assess the effects of increasing pressure on these structures. On 3 separate days, 10 subjects had ThermaCare heat or cold packs applied, for either 60 or 120 minutes for heat or 20 minutes for cold, to the palmer surface of the hand. Results Tissue changes were recorded as a response to pressure applied at 0, 5, 10, and 20 N. The size of the nerve and ligaments were not significantly altered by pressure with the hand at room temperature and after cold exposure. After heat, the nerve, ligaments, and tendons showed significantly more elasticity. Conclusions Application of cold to the hand may reduce compression of the carpal ligament and nerve. PMID:25669437

  7. NMR properties of human median nerve at 3 T: proton density, T1, T2, and magnetization transfer.

    PubMed

    Gambarota, Giulio; Mekle, Ralf; Mlynárik, Vladimír; Krueger, Gunnar

    2009-04-01

    To measure the proton density (PD), the T1 and T2 relaxation time, and magnetization transfer (MT) effects in human median nerve at 3 T and to compare them with the corresponding values in muscle. Measurements of the T1 and T2 relaxation time were performed with an inversion recovery and a Carr-Purcell-Meiboom-Gill (CPMG) imaging sequence, respectively. The MT ratio was measured by acquiring two sets of 3D spoiled gradient-echo images, with and without a Gaussian saturation pulse. The median nerve T1 was 1410 +/- 70 msec. The T2 decay consisted of two components, with average T2 values of 26 +/- 2 msec and 96 +/- 3 msec and normalized amplitudes of 78 +/- 4% and 22 +/- 4%, respectively. The dominant component is likely to reflect myelin water and connective tissue, and the less abundant component originates possibly from intra-axonal water protons. The value of proton density of MRI-visible protons in median nerve was 81 +/- 3% that of muscle. The MT ratio in median nerve (40.3 +/- 2.0%) was smaller than in muscle (45.4 +/- 0.5%). MRI-relevant properties, such as PD, T1 and T2 relaxation time, and MT ratio were measured in human median nerve at 3 T and were in many respects similar to those of muscle.

  8. Improving the radial nerve neurodynamic test: An observation of tension of the radial, median and ulnar nerves during upper limb positioning.

    PubMed

    Manvell, Joshua J; Manvell, Nicole; Snodgrass, Suzanne J; Reid, Susan A

    2015-12-01

    The radial nerve neurodynamic test (ULNT2b), used to implicate symptoms arising from the radial nerve, is proposed to selectively increase strain of the nerve without increasing strain of adjacent tissue, though this has not been established. This study aimed to determine the upper limb position that results in: (1) the greatest tension of the radial nerve and (2) the greatest difference in tension between the radial nerve and the other two major nerves of the upper limb: median and ulnar. Tension (N) of the radial, median and ulnar nerves was measured simultaneously using three buckle force transducers during seven upper limb positions in the axilla of ten embalmed whole body human cadavers (n = 20 limbs). Repeated measures analysis of variance (ANOVA) with Bonferroni post-hoc tests determined differences in tension between nerves and between limb positions. A Composite position consisting of ULNT2b (scapular depression, shoulder internal rotation, elbow extension, forearm pronation, wrist flexion) with the addition of shoulder abduction 40° and extension 25°, wrist ulnar deviation and thumb flexion demonstrated significantly greater tension of the radial nerve than any other tested position (mean tension 11.32N; 95% CI 10.25, 12.29, p < 0.01), including ULNT2b (2.20N; 1.84, 2.57; p < 0.01). Additionally, the Composite position demonstrated the greatest difference in tension between the radial and median (mean difference 4.88N; 95% CI 3.16, 6.61; p < 0.01) and radial and ulnar nerves (9.26N, 7.54, 10.99; p < 0.01). This position constitutes a biomechanically plausible test to detect neuropathic pain related to the radial nerve.

  9. Bilateral variations of brachial plexus involving the median nerve and lateral cord: An anatomical case study with clinical implications.

    PubMed

    Butz, James J; Shiwlochan, Devina G; Brown, Kevin C; Prasad, Alathady M; Murlimanju, Bukkambudhi V; Viswanath, Srikanteswara

    2014-01-01

    During the routine dissection of upper limbs of a Caucasian male cadaver, variations were observed in the brachial plexus. In the right extremity, the lateral cord was piercing the coracobrachialis muscle. The musculocutaneous nerve and lateral root of the median nerve were observed to be branching inferior to the lower attachment of coracobrachialis muscle. The left extremity exhibited the passage of the median nerve through the flat tendon of the coracobrachialis muscle near its distal insertion into the medial surface of the body of humerus. A variation in the course and branching of the nerve might lead to variant or dual innervation of a muscle and, if inappropriately compressed, could result in a distal neuropathy. Identification of these variants of brachial plexus plays an especially important role in both clinical diagnosis and surgical practice.

  10. Upper-extremity peripheral nerve injuries: a Louisiana State University Health Sciences Center literature review with comparison of the operative outcomes of 1837 Louisiana State University Health Sciences Center median, radial, and ulnar nerve lesions.

    PubMed

    Murovic, Judith A

    2009-10-01

    Data from three Louisiana State University Health Sciences Center (LSUHSC) publications were summarized for median, radial, and ulnar nerve injuries. Lesion types, repair techniques, and outcomes were compared for 1837 upper-extremity nerve lesions. Sharp laceration injury repair outcomes at various levels for median and radial nerves were equally good (91% each) and better than those for the ulnar nerve (73%). Secondary suture and graft repair outcomes were better for the median nerve (78% and 68%, respectively) than for the radial nerve (69% and 67%, respectively) and ulnar nerve (69% and 56%, respectively). In-continuity lesions with positive nerve action potentials during intraoperative testing underwent neurolysis with good results for the median (97%), radial (98%), and ulnar nerves (94%). For radial, median, and ulnar nerve in-continuity lesions with negative intraoperative nerve action potentials, good results occurred after suture repair in 88%, 86%, and 75% and after graft repair in 86%, 75% and 56%, respectively. Good outcomes after median and radial nerve repairs are attributable to the following factors: the median nerve's innervation of proximal, large finger, and thumb flexors; and the radial nerve's similar innervation of proximal muscles that do not perform delicate movements. This is contrary to the ulnar nerve's major nerve supply to the distal fine intrinsic hand muscles, which require more extensive innervation. The radial nerve also has a motor fiber predominance, reducing cross-motor/sensory reinnervation, and radial nerve-innervated muscles perform similar functions, decreasing the chance of innervation of muscles with opposite functions.

  11. Effect of neurotrophic factor, MDP, on rats' nerve regeneration.

    PubMed

    Fornazari, A A; Rezende, M R de; Mattar Jr, R; Taira, R I; Santos, G B dos; Paulos, R G

    2011-04-01

    Our objective was to determine the immune-modulating effects of the neurotrophic factor N-acetylmuramyl-L-alanyl-D-isoglutamine (MDP) on median nerve regeneration in rats. We used male Wistar rats (120-140 days of age, weighing 250-332 g) and compared the results of three different techniques of nerve repair: 1) epineural neurorrhaphy using sutures alone (group S - 10 rats), 2) epineural neurorrhaphy using sutures plus fibrin tissue adhesive (FTA; group SF - 20 rats), and 3) sutures plus FTA, with MDP added to the FTA (group SFM - 20 rats). Functional assessments using the grasp test were performed weekly for 12 weeks to identify recovery of flexor muscle function in the fingers secondary to median nerve regeneration. Histological analysis was also utilized. The total number and diameter of myelinated fibers were determined in each proximal and distal nerve segment. Two indices, reported as percentage, were calculated from these parameters, namely, the regeneration index and the diameter change index. By the 8th week, superiority of group SFM over group S became apparent in the grasping test (P = 0.005). By the 12th week, rats that had received MDP were superior in the grasping test compared to both group S (P < 0.001) and group SF (P = 0.001). Moreover, group SF was better in the grasping test than group S (P = 0.014). However, no significant differences between groups were identified by histological analysis. In the present study, rats that had received MDP obtained better function, in the absence of any significant histological differences.

  12. Influence of stimulation intensity on paired-pulse suppression of human median nerve somatosensory evoked potentials.

    PubMed

    Gatica Tossi, Mario A; Lillemeier, Ann-Sophie; Dinse, Hubert R

    2013-06-19

    Paired-pulse stimulation, the application of two stimuli in close succession, is a useful tool to investigate cortical excitability. Suppression of the second response after short interstimulus intervals characterizes paired-pulse behavior. Although paired-pulse suppression is often studied as a marker of cortical excitability in humans, little is known about the influence of stimulation intensity on paired-pulse suppression. To systematically explore the effect of stimulus intensity on paired-pulse suppression of median nerve somatosensory evoked potentials (MNSEPs), we recorded single-pulse or paired-pulse MNSEPs in healthy volunteers using stimulation intensities ranging from the sensory threshold to 1.2 times the motor threshold using interstimulus intervals of 10, 30, and 100 ms. Of the various somatosensory evoked potential components, only the N20-P25 component showed an effect of intensity, where higher intensities resulted in stronger paired-pulse suppression. However, when only intermediate intensities were considered, paired-pulse suppression was not or only weakly influenced. Our data suggest that stimulation intensity in contrast to single pulse-evoked MNSEPs has only a weak influence on the paired-pulse suppression of early MNSEPs. Paired-pulse suppression is believed to arise from inhibition generated by intracortical networks. The lack of intensity dependence within the range tested can be considered as a step toward creating invariance against fluctuations of stimulus intensity. Thus, intracortical computations as apparent in paired-pulse behavior might be characterized by different properties compared with feed-forward processing.

  13. Median nerve stimulation modulates extracellular signals in the primary motor area of a macaque monkey.

    PubMed

    Papazachariadis, Odysseas; Dante, Vittorio; Ferraina, Stefano

    2013-08-29

    Aiming to better define the functional influence of somatosensory stimuli on the primary motor cortex (M1) of primates, we investigated changes in extracellular neural activity induced by repetitive median nerve stimulation (MNS). We described neural adaptation and signal integration in both the multiunit activity (MUA) and the local field potential (LFP). To identify integration of initial M1 activity in the MNS response, we tested the correlation between peak amplitude responses and band energy preceding the peaks. Most of the sites studied in the M1 resulted responsive to MNS. MUA response peak amplitude decreased significantly in time in all sites during repetitive MNS, LFP response peak amplitude instead resulted more variable. Similarly, correlation analysis with the initial activity revealed a significant influence when tested using MUA peak amplitude modulation and a less significant correlation when tested using LFP peak amplitude. Our findings improve current knowledge on mechanisms underlying early M1 changes consequent to afferent somatosensory stimuli. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  14. High frequency oscillations after median nerve stimulations in healthy children and adolescents.

    PubMed

    Zanini, Sergio; Del Piero, Ivana; Martucci, Lucia; Restuccia, Domenico

    2017-10-01

    The aim of the present research was to address somatosensory high frequency oscillations (400-800Hz) in healthy children and adolescents in comparison with healthy adults. We recorded somatosensory evoked potentials following median nerve stimulation in nineteen resting healthy children/adolescents and in nineteen resting healthy adults with eyes closed. We administered six consecutive stimulation blocks (500 sweeps each). The presynaptic component of high frequency oscillations amplitudes was smaller in healthy children/adolescents than in healthy adults (no difference between groups was found as far as the postsynaptic component was concerned). Healthy children/adolescents had smaller presynaptic component than the postsynaptic one (the postsynaptic component amplitude was 145% of the presynaptic one), while healthy adults showed the opposite (reduction of the postsynaptic component to 80% of the presynaptic one). No habituation phenomena concerning high frequency oscillation amplitudes were registered in neither healthy children/adolescents nor healthy adults. These findings suggest that healthy children/adolescents present with significantly different pattern of somatosensory high frequency oscillations compared with healthy adults' ones. This different pattern is reasonably expression of higher cortical excitability of the developing brain cortex. Copyright © 2017 ISDN. Published by Elsevier Ltd. All rights reserved.

  15. The use of cross-correlation analysis between high-frequency ultrasound images to measure longitudinal median nerve movement.

    PubMed

    Dilley, A; Greening, J; Lynn, B; Leary, R; Morris, V

    2001-09-01

    Impaired nerve movement can lead to nerve injury (e.g., carpal tunnel syndrome). A noninvasive method to measure nerve movement in longitudinal section would enable an extensive analysis of nerve entrapment syndromes. A method has been developed using cross-correlation between successive high-frequency ultrasound (US) images to measure longitudinal movement of nerve and muscle. Control "phantom" experiments demonstrated the accuracy and reliability of this method at velocities of 1-10 mm/s. Increasing the frame interval between the compared frames enabled the accurate calculation of slower velocities. The correlation algorithm successfully measured relative movement when the US transducer was moved 1-3 mm over the surface of the forearm. Median nerve movement was repeatedly measured in the forearm during 30 degrees passive wrist extension in three subjects (range 2.63-4.12 mm) and index finger extension in seven subjects (range 1.59-4.48 mm). Median nerve movement values were consistent with those from cadaver studies.

  16. Reliability of the grip strength coefficient of variation for detecting sincerity in normal and blocked median nerve in healthy adults.

    PubMed

    Wachter, N J; Mentzel, M; Hütz, R; Gülke, J

    2017-04-01

    In the assessment of hand and upper limb function, detecting sincerity of effort (SOE) for grip strength is of major importance to identifying feigned loss of strength. Measuring maximal grip strength with a dynamometer is very common, often combined with calculating the coefficient of variation (CV), a measure of the variation over the three grip strength trials. Little data is available about the relevance of these measurements in patients with median nerve impairment due to the heterogeneity of patient groups. This study examined the reliability of grip strength tests as well as the CV to detect SOE in healthy subjects. The power distribution of the individual fingers and the thenar was taken into account. To assess reliability, the measurements were performed in subjects with a median nerve block to simulate a nerve injury. The ability of 21 healthy volunteers to exert maximal grip force and to deliberately exert half-maximal force to simulate reduced SOE in a power grip was examined using the Jamar(®) dynamometer. The experiment was performed in a combined setting with and without median nerve block of the same subject. The force at the fingertips of digits 2-5 and at the thenar eminence was measured with a sensor glove with integrated pressure receptors. For each measurement, three trials were recorded subsequently and the mean and CV were calculated. When exerting submaximal force, the subjects reached 50-62% of maximal force, regardless of the median nerve block. The sensor glove revealed a significant reduction of force when exerting submaximal force (P1 sensor) with (P<0.032) and without median nerve block (P<0.017). An increase in CV at submaximal force was found, although it was not significant. SOE can be detected with the CV at the little finger at using a 10% cut-off (sensitivity 0.84 and 0.92 without and with median nerve block, respectively). These findings suggest low reliability of the power grip measurement with the Jamar(®) dynamometer, as

  17. Normal and sonographic anatomy of selected peripheral nerves. Part I: Sonohistology and general principles of examination, following the example of the median nerve

    PubMed Central

    Sudoł-Szopińska, Iwona

    2012-01-01

    Ultrasonography is an established method for imaging peripheral nerves. It serves to supplement the physical examination, electromyography, and magnetic resonance imaging. It enables the identification of post-traumatic changes of nerves, neuropathies secondary to compression syndromes, inflammatory or neoplastic nerve lesions as well as the evaluation of postoperative complications. In certain situations, this technique is the imaging method of choice. It is increasingly used in anesthesiology for regional anesthesia. As in the case of other ultrasound imaging studies, the examination of peripheral nerves is non-invasive, well-tolerated by patients, and relatively inexpensive. This article presents the histological structure of peripheral nerves and their appearance in ultrasonography. It also presents the examination technique, following the example of the median nerve, and includes a series of diagrams and ultrasound images. The interpretation of the shape, echogenicity, thickness and vascularity of nerves is described, as well as their relation to the surrounding tissues. The “elevator technique”, which consists of locating a set nerve at a characteristic anatomic point, and following it proximally or distally, has been explained. The undisputed benefits of the ultrasound examination have been presented, including its advantages over other diagnostic methods. These advantages include the dynamic component of the ultrasound examination and the possibility of correlating the patient's symptoms with the ultrasound images. As an example, the proper anatomy and the ultrasonographic appearance of the median nerve were described. This nerve's course is presented, its divisions, and characteristic reference points, so as to facilitate its location and identification, and enable subsequent use of the aforementioned “elevator technique”. This article opens a series of publications concerning anatomy, technique of examination and pathologies of peripheral nerves

  18. Normal and sonographic anatomy of selected peripheral nerves. Part I: Sonohistology and general principles of examination, following the example of the median nerve.

    PubMed

    Kowalska, Berta; Sudoł-Szopińska, Iwona

    2012-06-01

    Ultrasonography is an established method for imaging peripheral nerves. It serves to supplement the physical examination, electromyography, and magnetic resonance imaging. It enables the identification of post-traumatic changes of nerves, neuropathies secondary to compression syndromes, inflammatory or neoplastic nerve lesions as well as the evaluation of postoperative complications. In certain situations, this technique is the imaging method of choice. It is increasingly used in anesthesiology for regional anesthesia. As in the case of other ultrasound imaging studies, the examination of peripheral nerves is non-invasive, well-tolerated by patients, and relatively inexpensive. This article presents the histological structure of peripheral nerves and their appearance in ultrasonography. It also presents the examination technique, following the example of the median nerve, and includes a series of diagrams and ultrasound images. The interpretation of the shape, echogenicity, thickness and vascularity of nerves is described, as well as their relation to the surrounding tissues. The "elevator technique", which consists of locating a set nerve at a characteristic anatomic point, and following it proximally or distally, has been explained. The undisputed benefits of the ultrasound examination have been presented, including its advantages over other diagnostic methods. These advantages include the dynamic component of the ultrasound examination and the possibility of correlating the patient's symptoms with the ultrasound images. As an example, the proper anatomy and the ultrasonographic appearance of the median nerve were described. This nerve's course is presented, its divisions, and characteristic reference points, so as to facilitate its location and identification, and enable subsequent use of the aforementioned "elevator technique". This article opens a series of publications concerning anatomy, technique of examination and pathologies of peripheral nerves.

  19. Morphology and metamorphosis of the peptidergic Va neurons and the median nerve system of the fruit fly, Drosophila melanogaster.

    PubMed

    Santos, Jonathan G; Pollák, Edit; Rexer, Karl-Heinz; Molnár, László; Wegener, Christian

    2006-10-01

    Metamorphosis is a fundamental developmental process and has been intensively studied for various neuron types of Drosophila melanogaster. However, detailed accounts of the fate of identified peptidergic neurons are rare. We have performed a detailed study of the larval morphology and pupal remodelling of identified peptidergic neurons, the CAPA-expressing Va neurons of D. melanogaster. In the larva, Va neurons innervate abdominal median and transverse nerves that are typically associated with perisympathetic organs (PSOs), major neurohaemal release sites in insects. Since median and transverse nerves are lacking in the adult, Va neurites have to undergo substantial remodelling during metamorphosis. We have examined the hitherto uncharacterised gross morphology of the thoracic PSOs and the abdominal median and transverse nerves by scanning electron microscopy and found that the complete reduction of these structures during metamorphosis starts around pupal stage P7 and is completed at P9. Concomitantly, neurite pruning of the Va neurons begins at P6 and is preceded by the high expression of the ecdysone receptor (EcR) subtype B1 in late L3 larvae and the first pupal stages. New neuritic outgrowth mainly occurs from P7-P9 and coincides with the expression of EcR-A, indicating that the remodelling of the Va neurons is under ecdysteroid control. Immunogold-labelling has located the CAPA peptides to large translucent vesicles, which are released from the transverse nerves, as suggested by fusion profiles. Hence, the transverse nerves may serve a neurohaemal function in D. melanogaster.

  20. Short-Latency Median-Nerve Somatosensory-Evoked Potentials and Induced Gamma-Oscillations in Humans

    ERIC Educational Resources Information Center

    Fukuda, Miho; Nishida, Masaaki; Juhasz, Csaba; Muzik, Otto; Sood, Sandeep; Chugani, Harry T.; Asano, Eishi

    2008-01-01

    Recent studies have suggested that cortical gamma-oscillations are tightly linked with various forms of physiological activity. In the present study, the dynamic changes of intracranially recorded median-nerve somatosensory-evoked potentials (SEPs) and somatosensory-induced gamma-oscillations were animated on a three-dimensional MR image, and the…

  1. Diagnostic Value of Virtual Touch Tissue Imaging Quantification for Evaluating Median Nerve Stiffness in Carpal Tunnel Syndrome.

    PubMed

    Zhang, Chen; Li, Miao; Jiang, Jue; Zhou, Qi; Xiang, Li; Huang, Yajuan; Ban, Wenrui; Peng, Wei

    2017-09-01

    To measure the shear wave velocity (SWV) of the median nerve by Virtual Touch tissue imaging quantification (VTIQ; Siemens AG, Erlangen, Germany) through the beginning of the carpal tunnel and to determine whether VTIQ could be used to diagnose carpal tunnel syndrome. This study recruited 49 consecutive patients (72 wrists) with a definitive diagnosis of carpal tunnel syndrome and 23 healthy volunteers (46 wrists). We measured the median nerve diameter and cross-sectional area by 2-dimensional sonography and the SWV by VTIQ. The interobserver variability was analyzed, and diagnostic values were evaluated by drawing a receiver operating characteristic curve. The median nerve SWV was significantly higher in the carpal tunnel syndrome group (3.857 m/s) than the control group (2.542 m/s; P < .05). A 3.0-m/s SWV cutoff value revealed sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 83.3%, 91.3%, 93.8%, 77.8%, and 86.4%, respectively. The interobserver agreement was excellent for the SWV measurements. The median nerve SWV at the carpal tunnel inlet is significantly higher in patients with carpal tunnel syndrome, for whom VTIQ appears to be a highly reproducible diagnostic technique. © 2017 by the American Institute of Ultrasound in Medicine.

  2. Short-Latency Median-Nerve Somatosensory-Evoked Potentials and Induced Gamma-Oscillations in Humans

    ERIC Educational Resources Information Center

    Fukuda, Miho; Nishida, Masaaki; Juhasz, Csaba; Muzik, Otto; Sood, Sandeep; Chugani, Harry T.; Asano, Eishi

    2008-01-01

    Recent studies have suggested that cortical gamma-oscillations are tightly linked with various forms of physiological activity. In the present study, the dynamic changes of intracranially recorded median-nerve somatosensory-evoked potentials (SEPs) and somatosensory-induced gamma-oscillations were animated on a three-dimensional MR image, and the…

  3. Laser welding of rat's facial nerve.

    PubMed

    Hwang, Kun; Kim, Sun Goo; Kim, Dae Joong; Lee, Chang Hyun

    2005-11-01

    The aim of this study is to compare regeneration of the severed nerves that were repaired by laser welding with those repaired by microsurgical suturing and evaluate the value in use of laser nerve welding in the head and neck area. In 12 rats the buccal branches of the facial nerves on the both sides were transected, and CO2 laser welding of the epineurium was performed on the right side and microsurgical suture technique was applied on the left side. In six rats Cholera Toxin B Subunit (CTb) was injected in the epineurium distal to the nerve anastomosis site at postoperative week 4. Another six rats were treated exactly in the same way in postoperative week 8. Six normal rats were used as controls. Intact facial nerve was observed after injection of CTb as well. Neurons of facial nuclei labeled positively by CTb were detected immunohistochemically, and the numbers were counted. CTb-positive neurons in the control group were 1311 +/- 258 (n = 6). CTb-positive neurons in the group (n = 6) with laser nerve welding were 1174 +/- 122 in postoperative week 4 and 1562 +/- 565 in postoperative week 8. CTb-positive neurons in the group (n = 6) with microsurgical suture were 1066 +/- 89 in postoperative week 4 and 1443 +/- 531 in postoperative week 8. CTb-positive neurons were seen significantly more in the group with laser welding than in the group with microsurgical suture in postoperative week (P = 0.028), but there was not much difference in postoperative week 8 (P = 0.463). None of 12 rats showed dehiscence at the nerve anastomosis done by laser welding. This study shows that nerve regeneration is more apparent in the nerve repaired by laser welding than in that repaired by microsurgical suture.

  4. Longitudinal Gliding of the Median Nerve in the Carpal Tunnel: Ultrasound Cadaveric Evaluation of Conventional and Novel Concepts of Nerve Mobilization.

    PubMed

    Meng, Stefan; Reissig, Lukas F; Beikircher, Reinhard; Tzou, Chieh-Han John; Grisold, Wolfgang; Weninger, Wolfgang J

    2015-12-01

    To evaluate median nerve excursion during conventional nerve gliding exercises and newly developed exercises, primarily comprising abduction and adduction of the fingers. Descriptive study. Anatomical dissection facility. Random sample of upper extremities of fresh whole-body human cadavers (N=18). Cadavers with neuromuscular diseases in the medical record or anatomic variations were excluded. Conventional and new nerve gliding exercises. Distances between markers applied into the nerve and markers in the periosteum were visualized with ultrasound and measured. Comparisons of nerve excursions between different exercises were performed. Conventional exercises led to substantial nerve gliding proximal to the carpal tunnel and between the head of the pronator teres (12 and 13.8mm, respectively), but it led to far less in the carpal tunnel (6.6mm). With our novel exercises, we achieved nerve gliding in the carpal tunnel of 13.8mm. No substantial marker movement could be detected during lateral flexion of the cervical spine. Although conventional nerve gliding exercises only lead to minimal nerve excursions in the carpal tunnel, our novel exercises with the abduction and adduction of the fingers result in substantial longitudinal gliding throughout the arm. Clinical trials will have to deliver the clinical evidence. Copyright © 2015 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  5. Ultrasound elastographic evaluation of the median nerve in pregnant women with carpal tunnel syndrome.

    PubMed

    Ogur, T; Yakut, Z I; Teber, M A; Alp, F; Turan, A; Tural, A; Gelisen, O

    2015-01-01

    To evaluate the median nerve (MN) in pregnant women with carpal tunnel syndrome (CTS) by using ultrasound elastography. 30 wrists of 20 pregnant women with CTS and 25 wrists of 14 healthy control pregnant women were evaluated by ultrasound and ultrasound elastography (UE). The MN in the patients' wrist was imaged to measure the cross-sectional area and longitudinally to calculate the elasticity value (EV) at four different locations (proximal carpal tunnel (CT) at the level of the pisiform, distal CT at the level of the hamate, middle of the CT and forearm at one centimeter above the CT). Clinical classification was performed according to a historic and objective scale of CTS. In the healthy pregnant women and pregnant women with CTS, MN area and EV were analyzed statistically by comparing with parity and clinical grade. There was a statistically significant difference for MN area between the patient and control groups (p = 0.001). A positive relationship was found between parity in pregnancy and clinical grade of the CTS (p = 0.035, Pearson's correlation coefficient = 0.386). Although MN elasticity for both groups was nearly the same in the proximal region of the CT, these values were decreased in the middle of the CT. MN elasticity values were smaller in the distal region of CT, and it was statistically significant in pregnant women with CTS (p = 0.02). Ultrasound elastography, which is a non-invasive, inexpensive and a favorable diagnosis technique, may be useful in the diagnosis of CTS, especially in conditions in which an invasive procedure would be problem, as in pregnancy.

  6. Clinical and electrodiagnostic abnormalities of the median nerve in Army dental assistants before and after training as preventive dental specialists.

    PubMed

    Greathouse, David G; Root, Tiffany M; Carrillo, Carla R; Jordan, Chelsea L; Pickens, Bryan B; Sutlive, Thomas G; Shaffer, Scott W; Moore, Josef F

    2011-01-01

    Dentists and dental hygienists have been reported as having a high prevalence of upper-extremity musculoskeletal disorders, including carpal tunnel syndrome. Unfortunately, previous research has not involved the impact of preventive dental specialist training on dental assistants. Therefore, the purpose of this study was to determine the presence of median and ulnar neuropathies in US Army dental assistants before and after training as preventive dental specialists. Thirty-five US Army dental assistants (24 female, 11 male; age range 18-41 years) volunteered for the study. Twenty-eight preventive dental specialist students completed both the pretraining and posttraining data collections. Subjects were evaluated during the first and last weeks of their 12-week course. Subjects completed a history form, were interviewed, and underwent a physical examination. Nerve conduction status of the median and ulnar nerves of both upper extremities were obtained by performing motor, sensory, comparison (unilateral median to ulnar distal motor and sensory latencies), and F-wave nerve conduction studies (NCS). Descriptive statistics for subject demographics and pre to post physical examination and nerve conduction variables were calculated. Chi square (χ²) analysis was also conducted to determine if a significant shift in the prevalence of neuropathies occurred following dental training. With the exception of comparison studies, pre-NCS and post-NCS electrophysiological variables were normal. Specifically, 9 subjects (26%) involving 14 hands (20%) were found to have meaningful (>1.0 millisecond) delayed median to ulnar distal motor latency comparisons in the pretraining assessment. Additionally, there was no statistically significant shift in the prevalence of electrodiagnostic abnormalities of the median nerve following the 12-week training program (χ²=0.280, P=.60). The prevalence of clinical and electrodiagnostic abnormalities of the median nerve in this sample of US Army

  7. Three-dimensional properties of GnRH neuroterminals in the median eminence of young and old rats1

    PubMed Central

    Yin, Weiling; Mendenhall, John M.; Monita, Monique; Gore, Andrea C.

    2010-01-01

    The decapeptide GnRH that regulates reproduction in all vertebrates is stored in, and secreted from, large dense-core secretory vesicles in nerve terminals in the median eminence. GnRH is released from these terminals with biological rhythms that are critical for the maintenance of normal reproduction. During reproductive aging in female rats, there is a loss of GnRH pulses and a diminution of the GnRH surge. However, information about the specific role of GnRH nerve terminals is lacking, particularly in the context of aging. We sought to gain novel ultrastructural information about GnRH neuroterminals by performing three-dimensional (3D) reconstructions of GnRH neuroterminals and their surrounding microenvironment in the median eminence of young (4-5 month) and old (22-24 month) ovariectomized Sprague-Dawley female rats. Median eminence tissues were freeze-plunge embedded, and serial ultrathin sections were collected on slot grids for immunogold labeling of GnRH immunoreactivity. Sequential images were used to create 3D models of GnRH terminals. These reconstructions provided novel perspectives into the morphological properties of GnRH terminals, and their neural and glial environment. We also noted that the cytoarchitectural features of the median eminence became disorganized with aging. Quantitative measures showed a significant decrease in the apposition between GnRH terminal membranes and glial cells. Our data suggest reproductive aging in rats is characterized by structural organizational changes to the GnRH terminal microenvironment in the median eminence. PMID:19757493

  8. Simultaneous Median-Radial Nerve Electrical Stimulation Revisited: An Accurate Approach to Carpal Tunnel Syndrome Diagnosis and Severity.

    PubMed

    Rodrigues, Thaís; Winckler, Pablo B; Félix-Torres, Vitor; Schestatsky, Pedro

    2016-12-01

    To assess the accuracy of an unusual test for CTS investigation and correlate it with clinical symptoms. Initially, we applied a visual analog scale for CTS discomfort (CTS-VAS) and performed a standard electrophysiologic test for CTS diagnosis (median-ulnar velocity comparison). Posteriorly, a blinded neurophysiologist performed the orthodromic simultaneous median-radial nerve stimulation (SMRS) at the thumb, with recording of both action potentials over the lateral aspect of the wrist. All hands (106) showed median-radial action potential splitting using the SMRS technique, in which was possible to measure the interpeak latencies (IPLs) between action potentials. The IPL and median nerve conduction velocity were different according to CTS intensity (Bonferroni; P < 0.001). There was significant correlation between IPL and median nerve conduction velocity (Spearman; r = -0.51; P < 0.01). In the same way, there was a significant correlation between IPL and median nerve conduction velocity with CTS-VAS (r = 0.6 and r = -0.3, respectively). The duration and unpleasantness of the SMRS procedure were lower when compared with standard approach (t Student < 0.001 for both comparisons). Twenty-nine symptomatic patients (39 hands) who did not fulfill criteria for CTS based on standard approach showed abnormal IPLs. The SMRS technique is a simple, sensitive, and tolerable approach for CTS diagnosis. Apart from that, the data from SMRS correlated better with clinical impact of CTS in comparison with the standard approach. Therefore, this method might be useful as adjunct to standard electrophysiologic approaches in clinical practice.

  9. [Initial positive deflection of the compound muscle action potential in the median nerve conduction studies can be originated from lumbrical muscles in patients with carpal tunnel syndrome].

    PubMed

    Matsumoto, S; Hasegawa, O

    2000-05-01

    In motor nerve conduction studies we sometimes encounter a small initial positive deflection (IPD) of the compound muscle action potential (CMAP). This potential represents a volume conduction from nearby muscles other than the objective muscle. We demonstrated recordings of motor nerve conduction studies from two patients with carpal tunnel syndrome (CTS). In patients with CTS IPDs can be recorded from a surface electrode above the abductor pollicis brevis when intense stimuli to the median nerve provoked a stimulus spread to the ulnar nerve. However, without this stimulus spread to the ulnar nerve, IPDs can be observed by contraction of median nerve innervated muscles. In the CTS thenar branch of the median nerve is apt to be more severely damaged than lumbrical branch. In such an occasion volume conduction from the lumbrical muscles is relatively large, which gives rise to the IPD in the CMAP recorded from abductor pollicis brevis. We reported two cases of IDPs originated from lumbrical muscles. The peak latencies were identical between IDP of abductor pollicis brevis recording and negative potential of lumbrical recording. These potentials didn't change by median nerve stimulation at the elbow 3 msec after the ulnar nerve stimulation at the wrist (collision technique). Finally, we repeat that IPDs in the median nerve conduction studies can be originated from not only the stimulus spread to the ulnar nerve but also the median nerve innervated lumbrical muscles in patients with CTS.

  10. Vibration testing: a pilot study investigating the intra-tester reliability of the Vibrameter for the Median and Ulnar nerves.

    PubMed

    James, Gill; Scott, Claire

    2012-08-01

    The measurement of vibration thresholds (VTs) is a sensitive test for identifying and monitoring neuropathies. Such a test needs established reliability. The purpose of this research was to evaluate the intra-tester reliability of VT measurements of the Median and Ulnar nerves in asymptomatic participants. A double blinded repeated measures study was carried out. The VTs of the Median and Ulnar nerves were measured on two occasions with seven days between measurements. Participants were trained in identifying the sensation before commencing measurement. 22 participants who fulfilled the inclusion criteria were recruited. Intra-rater reliability was analysed used the intra-class correlation. The median nerve showed excellent reliability (ICC = .922; standard error of the mean = .0225 μm; 'true' SEM = .045 μm; smallest real difference = .062 μm). Ulnar nerve reliability was 'substantial' (ICC = .632; standard error of the mean = .0225 μm; 'true' SEM = .055 μm; smallest real difference = .085 μm). The VT measurements showed excellent to substantial reliability. The Vibrameter has the potential for excellent reliability providing manual therapists practice the technique of using it. It could usefully be considered by manual therapists to support their practice.

  11. Peripheral median nerve stimulation for the treatment of iatrogenic complex regional pain syndrome (CRPS) type II after carpal tunnel surgery.

    PubMed

    Mirone, G; Natale, M; Rotondo, M

    2009-06-01

    We report on the use and follow-up of direct peripheral nerve stimulation of the median nerve for the treatment of iatrogenic complex regional pain syndrome (CRPS). A 56-year-old woman presented with CRPS type II in the right forearm and hand, which had started after multiple carpal tunnel surgeries and had lasted for 2 years. The visual analogue scale (VAS) score was 8-10 out of 10. After a successful 15-day trial of median nerve peripheral nerve stimulation via a quadripolar lead in the right carpal tunnel space, an implantable pulse generator was inserted in the right infraclavicular space. The VAS score decreased to 1-2 out of 10 and the patient regained the ability to sleep. After 36 months of follow-up, the patient was still experiencing good pain relief without other treatment. We conclude that peripheral nerve stimulation is easy to use in pain management and could offer a valid treatment option for iatrogenic CRPS type II.

  12. Anatomical study of the motor branches of the median nerve to the forearm and guidelines for selective neurectomy.

    PubMed

    Parot, Catalina; Leclercq, Caroline

    2016-07-01

    The median nerve is responsible for the motor innervation of most of the muscles usually involved in upper limb spasticity. Selective neurectomy is one of the treatments utilized to reduce spasticity. The purpose of this study was to describe the variations of the motor branches of the median nerve in the forearm and draw recommendations for an appropriate planning of selective neurectomy. The median nerve was dissected in the forearm of 20 fresh cadaver upper limbs. Measurements included number, origin, division, and entry point of each motor branch into the muscles. One branch for the pronator teres was the most common pattern. In 9/20 cases, it arose as a common trunk with other branches. A single trunk innervated the flexor carpi radialis with a common origin with other branches in 17/20 cases. Two, three or four branches innervated the flexor digitorum superficialis, the first one frequently through a common trunk with other branches. They were very difficult to identify unless insertions of pronator teres and flexor digitorum superficialis were detached. The flexor digitorum profundus received one to five branches and flexor pollicis longus one to two branches from the anterior interosseous nerve. There is no regular pattern of the motor branches of the median nerve in the forearm. Our findings differ in many points from the classical literature. Because of the frequency of common trunks for different muscles, we recommend the use of peroperative electrical stimulation. Selective neurotomy of flexor digitorum superficialis is technically difficult, because the entry point of some of their terminal branches occurs just below the arch and deep to the muscle belly.

  13. In vivo impedance measurements on nerves and surrounding skeletal muscles in rats and human body.

    PubMed

    Prokhorov, E; Llamas, F; Morales-Sánchez, E; González-Hernández, J; Prokhorov, A

    2002-05-01

    The aim of the work was to use impedance measurements to find the location of nerves under the human skin. In vivo impedance measurements were performed on exposed nervous and muscular tissues of rats. Similarly, the impedance measurements were also performed on the skin of six men, over the median nerve at the wrist, as well as 4-5 mm away from this location. Results obtained with rats have shown that the relative permittivity and conductivity of nerves are larger (by almost two orders of magnitude) than those observed for the muscular tissues surrounding the nerve. The results obtained on human skin in the frequency range of 20-200 kHz, when the electrodes were placed over the nerve, show lower resistance and higher capacitance than in the other areas measured. These preliminary results indicate that it may be possible to use impedance measurements to find the location of exposed nerves and also nerves under the skin.

  14. Prevalence of ulnar-to-median nerve motor fiber anastomosis (Riché-Cannieu communicating branch) in hand: An electrophysiological study.

    PubMed

    Ahadi, Tannaz; Raissi, Gholam Reza; Yavari, Masood; Majidi, Lobat

    2016-01-01

    Two main muscles studied in the hand for evaluation of median nerve injuries are opponens pollicis (OP) and abductor pollicis brevis (APB). However, Riché-Cannieu communicating branch (RCCB) may limit the use of these muscles in electrodiagnosis. This condition is confusing in the case of median nerve injuries. This study was conducted to evaluate the prevalence of RCCB. Twenty-three consecutive cases of complete median nerve injury were studied. Evoked responses via stimulation of median and ulnar nerves in the wrist and recording with needle in the thenar area were studied. Of the patients, 82.6% exhibited RCCB. In 14 (60.8%) cases the OP and in 19(82.6%) cases APB was supplied by the ulnar nerve. RCCB was detected to be 60.8% in OP and 82.6% in APB, so OP is preferable to APB in the study of median nerve.

  15. From the brachial plexus to the hand, multiple connections between the median and ulnar nerves may serve as bypass routes for nerve fibres.

    PubMed

    Yang, H; Gil, Y; Kim, S; Bang, J; Choi, H; Lee, H Y

    2016-07-01

    Axons from the median and ulnar nerves can pass to each other through aberrant connections between them. Multiple interconnections between the nerves may provide a detour route for nerve fibres going to the hand. We investigated the incidence of variations and the associations between them in 90 cadaveric upper limbs. In 91% of upper limbs, one to five variations were found, with several statistically significant associations. The contribution of the C8 nerve to the lateral cord was positively associated with an accessory contribution of the lateral cord to the ulnar nerve. The latter variation showed positive association with the occurrence of any of the variations in the hand itself. Ulnar innervation of the superficial head of the flexor pollicis brevis was positively associated with the Riche-Cannieu communication. The co-existence of the variations and their associations may be the explanation for unusual clinical findings related to median and ulnar conduction, which appear contrary to anatomical knowledge. © The Author(s) 2016.

  16. Diagnostic biopsy of the pronator teres and a motor branch of the median nerve: indications and technique.

    PubMed

    Dy, Christopher J; Lange, Dale J; Jones, Kristofer J; Garg, Rohit; DiCarlo, Edward F; Wolfe, Scott W

    2012-12-01

    Biopsy of muscle tissue and motor nerve is helpful in the neurological evaluation of patients who present with upper limb and/or diffuse motor weakness. The procedure is indicated to supplement clinical, serological, and imaging diagnostic work-up of myopathic and neuropathic disorders. We describe a surgical technique and clinical series of biopsy of the pronator teres muscle and a motor branch of the median nerve. We performed a retrospective review of 20 patients who underwent biopsy of the pronator teres and a motor branch of the median nerve as part of a clinical, serological, and radiographic evaluation for weakness of the upper extremity. All of the biopsies were performed by a single surgeon. The surgical technique is described. Follow-up visits with both the surgeon and the neurologist were reviewed to evaluate preoperative and postoperative neurological function to identify any changes in nerve or muscle function and any postoperative complications. Biopsied tissue was sufficient for pathological diagnosis in all 20 patients. Diagnoses included multifocal motor neuropathy in 14 patients, amyotrophic lateral sclerosis in 3 patients (2 sporadic; 1 familial), inclusion body myositis (1 patient), inflammatory myopathy (1 patient), and chronic inflammatory demyelinating polyneuropathy (1 patient). At a mean follow-up of 11 weeks (range, 5-31 wk), there were 6 minor surgical complications, all of which were superficial hematomas that resolved with use of a compressive wrap. Biopsy of the pronator teres and a motor branch of the median nerve was safe and effective. The technique is particularly useful when considering the diagnosis of multifocal motor neuropathy affecting the upper extremity. Copyright © 2012 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  17. Effect of hand size on the stimulation intensities required for median and ulnar sensory nerve conduction studies.

    PubMed

    Thanakiatpinyo, Thanitta; Srisawasdi, Gulapar

    2013-05-01

    To examine the effect of hand size on median and ulnar sensory nerve conduction study (NCS) stimulation intensities and pain scores. Prospective, single group design to compare main outcomes by using a standard distance of 14cm versus the proximal wrist crease in 3 different hand sizes. Electrodiagnostic laboratory in a department of rehabilitation medicine. Healthy volunteers (N=25) aged 20 to 30 years. Hand size was determined, based on the distance between the proximal wrist crease and the base of the long finger, resulting in 3 groups (≤11cm, >11-12cm, >12cm) with 12 hands per group. Antidromic median and ulnar sensory NCSs were performed. The nerves were randomly stimulated at the proximal wrist crease and 14cm from the recording electrode. Supramaximal stimulation intensities and 10-cm visual analog scale (VAS) pain scores at each stimulating site were recorded and compared. Thirty-six hands from 25 young healthy volunteers were studied. There was no correlation between the body mass index (BMI) and stimulation intensity, and BMI and VAS (r<0.3) in both median and ulnar nerves. Overall analysis showed that the stimulation intensity and VAS at 14cm were significantly greater than at the proximal wrist crease. Subgroup analysis showed the same result in all groups for the median sensory NCS, but in only the small hand group for the ulnar sensory NCS. When the same distance is used for NCSs regardless of patient size, smaller individuals required greater stimulation and reported greater discomfort. This may reflect greater nerve depth and suggests that one size fits all may not be the best approach with NCSs. Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  18. Median Nerve Injury Due to High-Pressure Water Jet Injection: A Case Report and Review of Literature.

    PubMed

    Emre, Ufuk; Unal, Aysun

    2009-08-01

    High-pressure injuries that occur accidentally are potentially destructive injuries that often affect the nondominant hands of young men. A variety of products such as paint, gasoline, grease, fuel oil, cement, thinner and solvents have been reported as destructive agents. High-pressure water jet injection injuries to soft tissues have rarely been reported. In this study, we present the first case of median nerve injury due to high-pressure water jet injection by a water spray gun.

  19. Longitudinal design for sonographic measurement of median nerve swelling with controlled exposure to physical work using an animal model

    PubMed Central

    Roll, Shawn C.; Evans, Kevin D.; Volz, Kevin R.; Sommerich, Carolyn M.

    2013-01-01

    This study examined the feasibility of a longitudinal design to sonographically measure swelling of the median nerve due to controlled exposure to a work task and to evaluate the relationship of changes in morphology to diagnostic standards. Fifteen macaca fascicularis pinched a lever in various wrist positions at a self-regulated pace (8 hours/day, 5 days/week, 18–20 weeks). Nerve conduction velocity (NCV) and cross-sectional area (CSA) were obtained every two weeks from baseline through working and a 6-week recovery. Trending across all subjects showed that NCV slowed and CSA at the carpal tunnel increased in the working arm, while no changes were observed in CSA either at the forearm or for any measure in the non-working arm. There was a small negative correlation between NCV and CSA in the working arm. This study provides validation that swelling can be observed using a longitudinal design. Longitudinal human studies are needed to describe the trajectory of nerve swelling for early identification of median nerve pathology. PMID:24139197

  20. Longitudinal design for sonographic measurement of median nerve swelling with controlled exposure to physical work using an animal model.

    PubMed

    Roll, Shawn C; Evans, Kevin D; Volz, Kevin R; Sommerich, Carolyn M

    2013-12-01

    In the study described here, we examined the feasibility of a longitudinal design to measure sonographically swelling of the median nerve caused by controlled exposure to a work task and to evaluate the relationship of changes in morphology to diagnostic standards. Fifteen macaques, Macaca fascicularis, pinched a lever in various wrist positions at a self-regulated pace (8 h/d, 5 d/wk, 18-20 wk). Nerve conduction velocity (NCV) and cross-sectional area (CSA) were measured every 2 wk from baseline through working and a 6-wk recovery. Trending across all subjects revealed that NCV slowed and CSA at the carpal tunnel increased in the working arm, whereas no changes were observed in CSA either at the forearm or for any measure in the non-working arm. There was a small negative correlation between NCV and CSA in the working arm. This study provides validation that swelling can be observed using a longitudinal design. Longitudinal human studies are needed to describe the trajectory of nerve swelling for early identification of median nerve pathology. Copyright © 2013 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  1. Nerve Cross-Bridging to Enhance Nerve Regeneration in a Rat Model of Delayed Nerve Repair

    PubMed Central

    2015-01-01

    There are currently no available options to promote nerve regeneration through chronically denervated distal nerve stumps. Here we used a rat model of delayed nerve repair asking of prior insertion of side-to-side cross-bridges between a donor tibial (TIB) nerve and a recipient denervated common peroneal (CP) nerve stump ameliorates poor nerve regeneration. First, numbers of retrogradely-labelled TIB neurons that grew axons into the nerve stump within three months, increased with the size of the perineurial windows opened in the TIB and CP nerves. Equal numbers of donor TIB axons regenerated into CP stumps either side of the cross-bridges, not being affected by target neurotrophic effects, or by removing the perineurium to insert 5-9 cross-bridges. Second, CP nerve stumps were coapted three months after inserting 0-9 cross-bridges and the number of 1) CP neurons that regenerated their axons within three months or 2) CP motor nerves that reinnervated the extensor digitorum longus (EDL) muscle within five months was determined by counting and motor unit number estimation (MUNE), respectively. We found that three but not more cross-bridges promoted the regeneration of axons and reinnervation of EDL muscle by all the CP motoneurons as compared to only 33% regenerating their axons when no cross-bridges were inserted. The same 3-fold increase in sensory nerve regeneration was found. In conclusion, side-to-side cross-bridges ameliorate poor regeneration after delayed nerve repair possibly by sustaining the growth-permissive state of denervated nerve stumps. Such autografts may be used in human repair surgery to improve outcomes after unavoidable delays. PMID:26016986

  2. Nerve cross-bridging to enhance nerve regeneration in a rat model of delayed nerve repair.

    PubMed

    Gordon, Tessa; Hendry, Michael; Lafontaine, Christine A; Cartar, Holliday; Zhang, Jennifer J; Borschel, Gregory H

    2015-01-01

    There are currently no available options to promote nerve regeneration through chronically denervated distal nerve stumps. Here we used a rat model of delayed nerve repair asking of prior insertion of side-to-side cross-bridges between a donor tibial (TIB) nerve and a recipient denervated common peroneal (CP) nerve stump ameliorates poor nerve regeneration. First, numbers of retrogradely-labelled TIB neurons that grew axons into the nerve stump within three months, increased with the size of the perineurial windows opened in the TIB and CP nerves. Equal numbers of donor TIB axons regenerated into CP stumps either side of the cross-bridges, not being affected by target neurotrophic effects, or by removing the perineurium to insert 5-9 cross-bridges. Second, CP nerve stumps were coapted three months after inserting 0-9 cross-bridges and the number of 1) CP neurons that regenerated their axons within three months or 2) CP motor nerves that reinnervated the extensor digitorum longus (EDL) muscle within five months was determined by counting and motor unit number estimation (MUNE), respectively. We found that three but not more cross-bridges promoted the regeneration of axons and reinnervation of EDL muscle by all the CP motoneurons as compared to only 33% regenerating their axons when no cross-bridges were inserted. The same 3-fold increase in sensory nerve regeneration was found. In conclusion, side-to-side cross-bridges ameliorate poor regeneration after delayed nerve repair possibly by sustaining the growth-permissive state of denervated nerve stumps. Such autografts may be used in human repair surgery to improve outcomes after unavoidable delays.

  3. Constituent ratio of motor fibers from the C5-C7 spinal nerves in the radial nerve is greater in pup rats than in adult rats.

    PubMed

    Nie, Mingbo; Chen, Liang; Gu, Yudong

    2012-06-01

    Clinically, injuries of C5-C7 of the brachial plexus cause falling of the wrist and fingers in infants but not in adults unless 4 consecutive spinal nerves are injured. The purpose of this study was to compare the constituent difference of spinal nerves in the radial nerve between pup and adult rats.A group of 16 pup rats and a group of 16 adult rats were each divided into 2 groups of 8 (P1 and A1 groups, C5-C6 were divided; P2 and A2 groups, C5-C7 were divided]). A nerve conduction study and histological examination were performed to evaluate radial nerve innervation to the extensor digitorum communis muscle after dividing the spinal nerves. Retrograde tracing with 5% cholera toxin B for anterior horn motoneurons of the spinal cord innervating the radial nerve was performed in 8 pup rats and 8 adult rats. Results showed that the division of C5-C7 caused more significant damage to radial nerve innervation to the extensor digitorum communis in pups than in adults, although the division of C5-C6 did not. In pups, the percentages (median with interquartile) of anterior horn motoneurons of the spinal cord innervating the radial nerve were 36.4 (28.3-38.5) in C5-C6, 28.1 (24.5-32.5) in C7, and 37.5 (36.5-39.3) in C8-T1. In adults, they were 24.2 (23.6-27.8) in C5-C6, 21.8 (19.5-26.3) in C7, and 50.7 (48.7-55.5) C8-T1.This study implies that C7 innervation in the radial nerve in humans may be more critical to the function of this nerve in infants than in adults.

  4. Comparison of the Nerve Conduction Parameters in Proximally and Distally Located Muscles Innervated by the Bundles of Median and Ulnar Nerves.

    PubMed

    Ongun, Nedim; Oguzhanoglu, Attila

    The aim of this study was to investigate and compare the conduction parameters of nerve bundles of median and ulnar nerves that innervate proximal and distal muscles. Thirty male and 30 female healthy volunteers between 18 and 70 years of age were enrolled in the study. The conduction parameters were recorded from the proximally located flexor carpi ulnaris, pronator teres and the flexor carpi radialis muscles to the distally located abductor digiti minimi and abductor pollicis brevis muscles for the ulnar and median nerves. Each nerve was stimulated at the region above the elbow and at the axillary region separately. The Student t test was used for statistical analysis, and Levene's test was used to assess whether or not the group variances exhibited a uniform distribution. The conduction velocities were faster (78.27 ± 6.55 vs. 67.83 ± 6.76 m/s, and 74.57 ± 5.66 and 74.23 ± 5.88 vs. 66.38 ± 6.85 m/s) and the durations of compound muscle action potential (CMAP) response were longer (15.65 ± 2.43 vs. 13.55 ± 1.78 ms, and 16.38 ± 2.39 and 16.04 ± 2.34 vs. 13.40 ± 1.79 ms) in proximally located muscles than in distally located muscles that are innervated either by ulnar or median nerves (p < 0.001). However, the CMAP amplitudes were smaller (2.52 ± 1.16 vs. 5.81 ± 3.13 mV, and 2.90 ± 1.20 and 3.59 ± 1.66 vs. 6.88 ± 2.77 mV) in proximal muscles than in distal muscles (p < 0.001). There was no significant difference (p > 0.05) between males and females regarding conduction velocities and CMAP amplitudes recorded from proximal and distal muscles. Proximal muscles innervated by median or ulnar nerves had lower CMAP amplitude values, longer CMAP durations and higher conduction velocities than distal muscles. These findings could reveal a temporal dispersion and phase cancellation due to desynchronized conduction during nerve stimulation. © 2016 S. Karger AG, Basel.

  5. Lipofibromatous hamartoma of the median nerve: a comprehensive review and systematic approach to evaluation, diagnosis, and treatment.

    PubMed

    Tahiri, Youssef; Xu, Liqin; Kanevsky, Jonathan; Luc, Mario

    2013-10-01

    Many modalities exist for diagnosing and treating lipofibromatous hamartoma (LFH), with no clear consensus. This is the first comprehensive study to review the existing literature on LFH of the median nerve and to suggest a systematic approach to its diagnosis and treatment. An electronic and manual search was conducted on Medline, Embase, Google Scholar, Current Contents, and Science Citation Index for original and review articles in English or French, from 1946 to November 2012. After 2 levels of screening, 106 references containing case reports were retained. Data extraction included patient demographics, clinical information, diagnostic modalities, treatment, and follow-up. A total of 180 cases were reported in the literature. One third of patients had associated macrodactyly (32%). Gender distribution is equal in LFH with or without macrodactyly, with most patients (71%) presenting before age 30 years. The main presenting symptom is an enlargement (88%) over the volar forearm, wrist, or hand, with or without digital hypertrophy, followed by paresthesia (39%). A soft, mobile, nontender, nonfluctuant mass with variable degree of compressive median neuropathy is found on physical examination. Biopsy, which reveals abundant mature fat cells and fibrous connective tissue infiltrating between nerve fascicles and the space between the epineurium and the perineurium, is not necessary because the pathognomonic features of the mass on magnetic resonance imaging offer an accurate diagnosis. Treatment of nerve compression symptoms and macrodactyly should be addressed separately. Carpal tunnel release is the mainstay of treatment for neuropathy, and ray or digital amputation, wedge osteotomy, middle phalangectomy with arthroplasty, and epiphysiodesis are suggested options in the management of macrodactyly. Based on our review of the literature, we propose an algorithm for the diagnosis and treatment of LFH of the median nerve with or without macrodactyly. Copyright © 2013

  6. Shear strain and motion of the subsynovial connective tissue and median nerve during single-digit motion.

    PubMed

    Yoshii, Yuichi; Zhao, Chunfeng; Henderson, Jacqueline; Zhao, Kristin D; An, Kai-Nan; Amadio, Peter C

    2009-01-01

    The objective of this study was to measure the relative motion of the middle finger flexor digitorum superficialis (FDS) tendon, its adjacent subsynovial connective tissue (SSCT), and the median nerve during single-digit motion within the carpal tunnel in human cadaver specimens and to estimate the relative motions of these structures in different wrist positions. Using fluoroscopy during simulated single-digit flexion, we measured the relative motion of the middle finger FDS tendon, SSCT, and median nerve within the carpal tunnel in 12 human cadavers. Measurements were obtained for 3 wrist positions: neutral, 60 degrees flexion, and 60 degrees extension. After testing with an intact carpal tunnel was completed, the flexor retinaculum was cut with a scalpel, and the same testing procedure was repeated for each wrist position. The relative motions of the tendon, SSCT, and median nerve were compared using a shear index, defined as the ratio of the difference in motion along the direction of tendon excursion between 2 tissues divided by tendon excursion, expressed as a percentage. Both tendon-SSCT and tendon-nerve shear index were significantly higher in the 60 degrees of wrist flexion and extension positions than in the neutral position. After division of the flexor retinaculum, the shear index in the 60 degrees wrist extension position remained significantly different from that of the neutral position. We have found that the relative motion between a tendon and SSCT in the carpal tunnel is maximal at extremes of wrist motion. These positions may predispose the SSCT to shear injury.

  7. Ultrasonography of the Transverse Movement and Deformation of the Median Nerve and Its Relationships With Electrophysiological Severity in the Early Stages of Carpal Tunnel Syndrome.

    PubMed

    Park, Donghwi

    2017-04-19

    To date, there have been conflicting suggestions regarding the initial pathogenesis of carpal tunnel syndrome (CTS). It has been characterized as either inflammation of the median nerve caused by compression or noninflammatory fibrosis of the subsynovial connective tissue (SSCT). To investigate the initial pathogenesis of CTS, we compared the deformation and displacement of the median nerve in accordance with the electrophysiological severity between patients with CTS (via the Bland scale) and healthy controls. Cross-sectional, case-control study. General teaching hospital, rehabilitation unit. Thirteen hands of 10 healthy participants and 39 hands of 27 patients with CTS were recruited and classified into 4 groups (stage 0-3) according to the severity of the electrodiagnostic test results. Ultrasound images of the median nerve in response to the wrist and finger motions were analyzed. We measured the deformation of the median nerve (the maximal change values of the median nerve area, and aspect ratio of the minimum-enclosing rectangle [MER]) and movement of the median nerve (the maximal change value of the median nerve displacement) in response to the motions of wrists and finger. The maximal change value of the median nerve displacement was normalized with respect to the width of the wrist. Moreover, the maximal change values of the median nerve area, and the aspect ratio of the MER, were also normalized to the median nerve area and the aspect ratio of the MER in wrist-neutral position with finger extension. CTS patients in stage 3 showed a significantly lower normalized maximal change of the median nerve movement compared with CTS patients in stages 0, 1, and 2 (P <.001). Regarding the deformation of the median nerve, however, there were statistically significant differences among all groups (area, P < .001; MER, P <.001). According to multivariate logistic regression analysis, the normalized maximal change of the aspect ratio of the MER is a meaningful

  8. Clinical and electrodiagnostic abnormalities of the median nerve in US Army Dental Assistants at the onset of training.

    PubMed

    Shaffer, Scott W; Moore, Rebecca; Foo, Shannon; Henry, Nathan; Moore, Josef H; Greathouse, David G

    2012-01-01

    Dental personnel including dentists, dental hygienists, and dental assistants have been reported as having a high prevalence of upper-extremity musculoskeletal disorders, including carpal tunnel syndrome. Previous research has not involved dental assistant students at the onset of dental training. Therefore, the purpose of this study was to determine the presence of median and ulnar neuropathies in US Army dental assistants at the onset of their training. Fifty-five US Army Soldiers (28 female, 27 male) enrolled in the Dental Assistant (68E) course, volunteered to participate in the study. The mean age of the dental assistant students was 24±7.2 years (range 18-41 years). There were 45 right handed dental assistant students, and the mean length of time in the Army prior to dental training was 27 months (range 3-180 months). Subjects were evaluated during the first week of their 10-week dental assistant course. Subjects completed a history form, were interviewed, and underwent a physical examination. Electrophysiological status of the median and ulnar nerves of both upper extremities was obtained by performing motor and sensory nerve conduction studies. Descriptive statistics for subject demographics and nerve conduction study variables were calculated. Six of the 55 subjects (11%) presented with abnormal electrophysiologic values suggestive of median mononeuropathy at or distal to the wrist. Five of the subjects had abnormal electrophysiologic values in both hands. Five of these 6 subjects had clinical examination findings consistent with the electrophysiological findings. The ulnar nerve electrophysiologic assessment was normal in all subjects sampled. The prevalence of median mononeuropathies in this sample of Army dental assistants at the onset of training is greater than 5% prevalence reported in previous healthy populations and is less than 26% prevalence in previous research examining Army dental assistants with dental work experience. Median neuropathy at

  9. Surgical repair of a 30 mm long human median nerve defect in the distal forearm by implantation of a chitosan-PGA nerve guidance conduit.

    PubMed

    Gu, Jianhui; Hu, Wen; Deng, Aidong; Zhao, Qing; Lu, Shibi; Gu, Xiaosong

    2012-02-01

    This paper describes a clinical case study in which a chitosan/polyglycolic acid nerve guidance conduit (chitosan-PGA NGC) was utilized to repair a 30 mm long median nerve defect in the right distal forearm of a 55 year-old male patient. Thirty-six months after the nerve repair, the palm abduction of the thumb and the thumb-index digital opposition recovered, facilitating the patient to accomplish fine activities, such as handling chopsticks. Static two-point discrimination measured 14, 9 and 9 mm in the thumb, index and middle fingers of the right hand. Reproducible compound muscle action potentials were recorded on the right abductor pollicis. The ninhydrin test, a classical method for assessing sympathetic nerve function, showed partial recovery of the perspiration function of the injured thumb, index and middle fingers. This repair case suggested a possible strategy for the clinical reconstruction of extended defects in human peripheral nerve trunks by the implantation of chitosan-PGA NGCs. Copyright © 2011 John Wiley & Sons, Ltd.

  10. Sensory reanimation of the hand by transfer of the superficial branch of the radial nerve to the median and ulnar nerve.

    PubMed

    Schenck, Thilo L; Lin, Shenyu; Stewart, Jessica K; Koban, Konstantin C; Aichler, Michaela; Rezaeian, Farid; Giunta, Riccardo E

    2016-12-01

    It remains a surgical challenge to treat high-grade nerve injuries of the upper extremity. Extra-anatomic reconstructions through the transfer of peripheral nerves have gained clinical importance over the past decades. This contribution outlines the anatomic and histomorphometric basis for the transfer of the superficial branch of the radial nerve (SBRN) to the median nerve (MN) and the superficial branch of the ulnar nerve (SBUN). The SBRN, MN, and SBUN were identified in 15 specimens and the nerve transfer performed. A favorable site for coaptation was chosen and its location described using relevant anatomical landmarks. Histomorphometric characteristics of donor and target were compared to evaluate the chances of a clinical success. A suitable location for dissecting the SBRN was identified prior to its first bifurcation. Coaptations were possible near the pronator quadratus muscle, approximately 22 cm distal to the lateral epicondyle of the humerus. The MN and SBUN had to be dissected interfasciculary over 82 ± 5.7 mm and 49 ± 5.5 mm, respectively. Histomorphometric analysis revealed sufficient donor-to-recipient axon ratios for both transfers and identified the SBRN as a suitable donor with high axon density. Our anatomic and histomorphometric results indicate that the SBRN is a suitable donor for the MN and SBUN at wrist level. The measurements show feasibility of this procedure and shall help in planning this sensory nerve transfer. High axon density in the SBRN identifies it or its branches an ideal candidate for sensory reanimation of fingers and thumbs.

  11. Subchronic stimulation performance of transverse intrafascicular multichannel electrodes in the median nerve of the Göttingen minipig.

    PubMed

    Harreby, Kristian R; Kundu, Aritra; Yoshida, Ken; Boretius, Tim; Stieglitz, Thomas; Jensen, Winnie

    2015-02-01

    This work evaluated the subchronic stimulation performance of an intraneural multichannel electrode (transverse intrafascicular multichannel electrode, TIME) in a large human-sized nerve. One or two TIMEs were implanted in the right median nerve above the elbow joint in four pigs for a period of 32 to 37 days (six TIMEs in total). The ability of the contact sites to recruit five muscles in the forelimb was assessed via their evoked electromyographic responses. Based on these responses, a selectivity index was defined. Four TIMEs were able to selectively recruit a subset of muscles throughout the implantation period. The required recruitment current significantly increased, while there was a tendency for the recruitment selectivity to decrease over time. Histological assessment showed that all TIMEs remained inside the nerve and that they were located between fascicles. The average thickness of the encapsulation of the electrode was estimated to be 115.4 ± 51.5 μm (mean ± SD). This study demonstrates the feasibility of keeping the TIME electrodes fixed and functional inside a large polyfascicular human-sized nerve in a subchronic setting. Copyright © 2014 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  12. Rat-derived processed nerve allografts support more axon regeneration in rat than human-derived processed nerve xenografts.

    PubMed

    Wood, Matthew D; Kemp, Stephen W P; Liu, Edward H; Szynkaruk, Mark; Gordon, Tessa; Borschel, Gregory H

    2014-04-01

    Processed nerve allografts are increasingly used as "off the shelf" nerve replacements for surgically bridging nerve gaps. Benchmarking the regenerative capacity of a commercially available human-derived nerve or xenograft in a rat nerve injury model would provide a convenient platform for future studies seeking to modify the processed nerve graft. Human and rat processed nerve grafts were used to bridge a 14 mm defect in a Sprague-Dawley rat sciatic nerve. Reversed autografts served as a positive control group. Twelve weeks following surgery, the distal nerve stumps were retrograde labeled and harvested for histology and histomorphometry. The cross-sectional areas of the human- and rat-derived processed nerve grafts were similar. Neuron counts and myelinated axon counts following use of the human-derived processed xenografts were decreased compared with those obtained from both the rat-derived processed nerve allografts and the autografts; the rat-derived processed nerve allografts were statistically equivalent to autografts. Measures of nerve fiber diameter and myelination revealed inferior axon regeneration maturity in both processed nerve grafts compared with autografts. Processed xenografts showed significantly reduced regeneration compared with autografts or processed allografts indicating that cross-species immunological reactions are important considerations in this rat model.

  13. Changes in Clinical Symptoms, Functions, and the Median Nerve Cross-Sectional Area at the Carpal Tunnel Inlet after Open Carpal Tunnel Release

    PubMed Central

    Koh, Young-Do; Kim, Jong Oh; Choi, Shin Woo

    2016-01-01

    Background The aim of this study was to investigate the relationship between clinical symptoms and cross-sectional area (CSA) of the median nerve at the carpal tunnel inlet before and after open carpal tunnel release (CTR). Methods Thirty-two patients (53 hands) that underwent open CTR for idiopathic carpal tunnel syndrome were prospectively enrolled. Median nerve CSA at the carpal tunnel inlet was measured preoperatively and at 2 and 12 weeks after CTR by high resolution ultrasonography. The Boston carpal tunnel questionnaire (BCTQ) was also completed at these times. Results BCTQ symptom (BCTQ-S) score was significantly improved at 2 weeks postoperatively, but BCTQ function (BCTQ-F) score and CSA were significantly improved at 12 weeks postoperatively. Preoperative CSA was significantly correlated with preoperative BCTQ-S and BCTQ-F scores but was not significantly correlated with postoperative BCTQ scores or postoperative changes in BCTQ scores. Postoperative median nerve CSA was not significantly correlated with postoperative BCTQ-S or BCTQ-F scores, and postoperative changes in median nerve CSA were not significantly correlated with postoperative changes in BCTQ-S or BCTQ-F scores. Conclusions The study shows clinical symptoms resolve rapidly after open CTR, but median nerve swelling and clinical function take several months to recover. In addition, preoperative median nerve swelling might predict preoperative severities of clinical symptoms and functional disabilities. However, postoperative reductions in median nerve swelling were not found to reflect postoperative reductions in clinical symptoms or functional disabilities. PMID:27583113

  14. [Electroneuromyographic study of the median nerve: peculiarities of M-response from the anterior forearm muscles during stimulation of the brachial plexus].

    PubMed

    Khodulev, V I; Nechipurenko, N I; Antonov, I P

    2006-01-01

    Motor fibers of the median nerve innervating the anterior forearm muscles during stimulation of the brachial plexus have been studied. A role of forearm muscles innervated by the cubital and radial nerves in the formation of the M-response recorded from the anterior forearm muscles has been determined. Surface stimulating and recording electrodes have been used, with the active recording electrode being placed on the border between the upper and the middle one third of the anterior forearm surface and the reference electrode--in the area of the lower one third of the forearm. Nerve stimulation was conducted at 5 points: in the region of elbow flexion (median nerve); in the border between the middle and the lower one third of the inner side of the shoulder (median and cubital nerves); in the Erb's point or in the axillary space (brachial plexus); in the sulcus of ulnar nerve (cubital nerve); on the border between the middle and the lower one third of the outer shoulder surface (radial nerve). During stimulation of the brachial plexus, the M-response recorded from the anterior forearm muscles is caused mostly by the median nerve. The radial nerve also exerts a significant influence on development of the M-response. A role of the cubital nerve is minimal (p>0.05). The M-response recorded from the anterior forearm surface during brachial plexus stimulation is a result of summed potentials of motor units both of the anterior forearm muscles innervated by the median and cubital nerves and of the lateral and posterior groups innervated by the radial nerve.

  15. Clinical and electrophysiological comparison of different methods of soft tissue coverage of the median nerve in recurrent carpal tunnel syndrome.

    PubMed

    Stütz, Nicolas M; Gohritz, Andreas; Novotny, Alexander; Falkenberg, Udo; Lanz, Ulrich; van Schoonhoven, Jörg

    2008-03-01

    To evaluate the clinical and electrophysiological results of 26 patients treated with either a hypothenar fat flap or a synovial flap to prevent recurrent scar compression of the median nerve after previously failed carpal tunnel decompression. A total of 26 patients underwent flap coverage as a result of a nerve tethering attributable to a position within scar; 15 were covered by a synovial flap and 11 by a hypothenar fat flap. Only patients in whom the median nerve was significantly enveloped in scar tissue were included. All candidates underwent a thorough clinical examination and nerve conduction test. The pre- and postoperative nerve conduction tests and the results of the two groups were statistically compared. The reduction rates of brachial nocturnal pain and pillar pain were 25 and 25%, respectively, in the synovial flap group and 64 and 37%, respectively, in the hypothenar fat flap group. The reduction rates of a positive Tinel's sign (25%) and a positive Phalen's test (13%) were lower in the synovial flap group compared with hypothenar fat flap coverage (55% Tinel's sign, 46% Phalen's test). Thenar atrophy and paresthesia were reduced in 44 and 62%, respectively, in the synovial flap group and in 46 and 64%, respectively, in the hypothenar fat flap group. The overall patient satisfaction (73%) and the Disabilities of the Arm, Shoulder and Hand score (31 points) appeared superior in the hypothenar fat flap group compared with the synovial flap group (56%; 37 points). Nerve conduction tests demonstrated a significant improvement when comparing the pre- and postoperative measurements in both groups. Distal motor latency decreased in the hypothenar fat flap group from 6.81 ms to 4.92 msec (P = 0.01; mean value) and in the synovial flap group from 6.04 ms to 4.43 msec (P < 0.001; mean value). Coverage by an ulnar-based hypothenar fat flap appeared to produce superior clinical results compared with coverage with synovial tissue from adjacent flexor tendons

  16. Intensity sensitive modulation effect of theta burst form of median nerve stimulation on the monosynaptic spinal reflex.

    PubMed

    Yeh, Kuei-Lin; Fong, Po-Yu; Huang, Ying-Zu

    2015-01-01

    The effects of electrical stimulation of median nerve with a continuous theta burst pattern (EcTBS) on the spinal H-reflex were studied. Different intensities and durations of EcTBS were given to the median nerve to 11 healthy individuals. The amplitude ratio of the H-reflex to maximum M wave (H/M ratio), corticospinal excitability and inhibition measured using motor evoked potentials (MEPs), short-interval intracortical inhibition and facilitation (SICI/ICF), spinal reciprocal inhibition (RI), and postactivation depression (PAD) were measured before and after EcTBS. In result, the H/M ratio was reduced followed by EcTBS at 90% H-reflex threshold, and the effect lasted longer after 1200 pulses than after 600 pulses of EcTBS. In contrast, EcTBS at 110% threshold facilitated the H/M ratio, while at 80% threshold it had no effect. Maximum M wave, MEPs, SICI/ICF, RI, and PAD all remained unchanged after EcTBS. In conclusion, EcTBS produced lasting effects purely on the H-reflex, probably, through effects on postsynaptic plasticity. The effect of EcTBS depends on the intensity and duration of stimulation. EcTBS is beneficial to research on mechanisms of human plasticity. Moreover, its ability to modulate spinal excitability is expected to have therapeutic benefits on neurological disorders involving spinal cord dysfunction.

  17. Dorsolateral subthalamic neuronal activity enhanced by median nerve stimulation characterizes Parkinson's disease during deep brain stimulation with general anesthesia.

    PubMed

    Tsai, Sheng-Tzung; Chuang, Wei-Yi; Kuo, Chung-Chih; Chao, Paul C P; Chen, Tsung-Ying; Hung, Hsiang-Yi; Chen, Shin-Yuan

    2015-12-01

    Deep brain stimulation (DBS) surgery under general anesthesia is an alternative option for patients with Parkinson's disease (PD). However, few studies are available that report whether neuronal firing can be accurately recorded during this condition. In this study the authors attempted to characterize the neuronal activity of the subthalamic nucleus (STN) and elucidate the influence of general anesthetics on neurons during DBS surgery in patients with PD. The benefit of median nerve stimulation (MNS) for localization of the dorsolateral subterritory of the STN, which is involved in sensorimotor function, was explored. Eight patients with PD were anesthetized with desflurane and underwent contralateral MNS at the wrist during microelectrode recording of the STN. The authors analyzed the spiking patterns and power spectral density (PSD) of the background activity along each penetration track and determined the spatial correlation to the target location, estimated mated using standard neurophysiological procedures. The dorsolateral STN spiking pattern showed a more prominent bursting pattern without MNS and more oscillation with MNS. In terms of the neural oscillation of the background activity, beta-band oscillation dominated within the sensorimotor STN and showed significantly more PSD during MNS (p < 0.05). Neuronal firing within the STN could be accurately identified and differentiated when patients with PD received general anesthetics. Median nerve stimulation can enhance the neural activity in beta-band oscillations, which can be used as an index to ensure optimal electrode placement via successfully tracked dorsolateral STN topography.

  18. Wake-promoting actions of median nerve stimulation in TBI-induced coma: An investigation of orexin-A and orexin receptor 1 in the hypothalamic region.

    PubMed

    Zhong, Ying-Jun; Feng, Zhen; Wang, Liang; Wei, Tian-Qi

    2015-09-01

    A coma is a serious complication, which can occur following traumatic brain injury (TBI), for which no effective treatment has been established. Previous studies have suggested that neural electrical stimulation, including median nerve stimulation (MNS), may be an effective method for treating patients in a coma, and orexin‑A, an excitatory hypothalamic neuropeptide, may be involved in wakefulness. However, the exact mechanisms underlying this involvement remain to be elucidated. The present study aimed to examine the arousal‑promoting role of MNS in rats in a TBI‑induced coma and to investigate the potential mechanisms involved. A total of 90 rats were divided into three groups, comprising a control group, sham‑stimulated (TBI) group and a stimulated (TBI + MNS) group. MNS was performed on the animals, which were in a TBI‑induced comatose state. Changes in the behavior of the rats were observed following MNS. Subsequently, hypothalamic tissues were extracted from the rats 6, 12 and 24 h following TBI or MNS, respectively. The expression levels of orexin‑A and orexin receptor‑1 (OX1R) in the hypothalamus were examined using immunohistochemistry, western blotting and an enzyme‑linked immunosorbent assay. The results demonstrated that 21 rats subjected to TBI‑induced coma exhibited a restored righting reflex and response to pain stimuli following MNS. In addition, ignificant differences in the expression levels of orexin‑A and OXIR were observed among the three groups and among the time‑points. Orexin‑A and OX1R were upregulated following MNS. The rats in the stimulated group reacted to the MNS and exhibited a re‑awakening response. The results of the present study indicated that MNS may be a therapeutic option for TBI‑induced coma. The mechanism may be associated with increasing expression levels of the excitatory hypothalamic neuropeptide, orexin-A, and its receptor, OX1R, in the hypothalamic region.

  19. Ultrasonographic Median Nerve Changes After Repeated Wheelchair Transfers in Persons With Paraplegia: Relationship With Subject Characteristics and Transfer Skills.

    PubMed

    Hogaboom, Nathan S; Diehl, Jessica A; Oyster, Michelle L; Koontz, Alicia M; Boninger, Michael L

    2016-04-01

    Wheelchair users with spinal cord injuries are susceptible to peripheral neuropathies from overuse, yet no studies have established a relationship between median neuropathy and wheelchair transfers. A more thorough understanding of how transfers and technique contribute to pathologic conditions may guide interventions that curtail its development. To evaluate the effects of repeated transfers on ultrasound markers for carpal tunnel syndrome (CTS) in people with spinal cord injuries and to relate changes to subject characteristics and transfer skills. Cross-sectional, repeated measures. Research laboratory and national wheelchair sporting events. A convenience sample of 30 wheelchair users with nonprogressive paraplegia were recruited via research registries and at the 2013 National Veterans Wheelchair Games and 2014 Paralyzed Veterans of America Buckeye Games. Participants were older than 18 years and could complete transfers independently within 30 seconds without use of their leg muscles. Demographic questionnaires and physical examinations for CTS were completed. Quantitative ultrasound techniques were used to measure changes in the median nerve after a repeated-transfers protocol. The Transfer Assessment Instrument (TAI) was completed to quantify transfer ability. Median nerve cross-sectional area at the level of the pisiform (PCSA) and swelling ratio (SR), transfer quality, and skills via the TAI. PCSA increased after repeated transfers (P < .025). Participants who used safe hand positions had a lower baseline SR (β = -0.728; P < .01). Participants with a higher body weight had a lower baseline SR provided they performed higher quality transfers. Participants who scooted to the front of the seat prior to transferring (TAI item 7; β = 0.144; P < .05) and who weighed more (β = 0.142; P < .05) exhibited greater increases in PCSA in response to transfers. An acute increase was observed in median nerve CSA at the pisiform after repeated wheelchair transfers

  20. 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.

  1. Do anthropometric measurements of the hand impact the histological structure of the human median nerve at the level of the carpal tunnel?

    PubMed

    Tomaszewski, Krzysztof A; Tomaszewska, Iwona M; Kurzydło, Wojciech; Skrzat, Janusz; Matuszyk, Aleksandra; Kłosiński, Michał; Mizia, Ewa

    2012-01-01

    The literature lacks data on the histological structure of the median nerve on the level of the carpal tunnel, and its possible correlations with the anthropometric measurements of the hand. The aim of this study was to assess the anthropometric measurements of human cadaver hands and their median nerves histological structure and whether a correlation existed between these two. This study has been conducted using cadavers stored in a 10% solution of formaldehyde at the Department of Anatomy of the Jagiellonian University Medical College (JUMC) and cadavers from the Department of Forensic Medicine JUMC. Before dissection anthropometric measurements were carried out. After dissection the median nerves were stained with haematoxylin and eosin and histological slides were prepared. These were later photographed (16 x magnification) and analysed using ImageJ software. The studied group comprised 8 women and 22 men (age between 23-92 years). Anthropometric measurements comparison by gender revealed statistically significantly larger CR-CU, MR-MU and TS-ID distances in men then in women. When comparing sides, the cross-sectional area (CSA) of the right median nerve (0.216 +/- 0.06 cm2) was statistically significantly larger (p = 0.017) then the CSA of the left median nerve (0.173 +/- 0.05 cm2). No correlation was noted between the anthropometric and histological measurements obtained in this study. Anthropometric measurements of the hand do not impact the histological structure of the human median nerve at the level of the carpal tunnel. Nerve bundles of the median nerve, at the level of the carpal tunnel, display no particular type of arrangement.

  2. Waterjet dissection of peripheral nerves: an experimental study of the sciatic nerve of rats.

    PubMed

    Tschan, Christoph A; Keiner, Doerthe; Müller, Harald D; Schwabe, Kerstin; Gaab, Michael R; Krauss, Joachim K; Sommer, Clemens; Oertel, Joachim

    2010-12-01

    Although waterjet dissection has been well evaluated in intracranial pathologies, little is known of its qualities in peripheral nerve surgery. Theoretically, the precise dissection qualities could support the separation of nerves from adjacent tissues and improve the preservation of nerve integrity in peripheral nerve surgery. To evaluate the potential of the new waterjet dissector in peripheral nerve surgery. Waterjet dissection with pressures of 20 to 80 bar was applied on the sciatic nerves of 101 rats. The effect of waterjet dissection on the sciatic nerve was evaluated by clinical tests, neurophysiological examinations, and histopathological studies up to 12 weeks after surgery. With waterjet pressures up to 30 bar, the sciatic nerve was preserved in its integrity in all cases. Functional damaging was observed at pressures of 40 bar and higher. However, all but 1 rat in the 80 bar subgroup showed complete functional regeneration at 12 weeks after surgery. Histopathologically, small water bubbles were observed around the nerves. At 40 bar and higher, the sciatic nerves showed signs of direct nerve injury. However, all these animals showed nerve regeneration after 12 weeks, as demonstrated by histological studies. Sciatic nerves were preserved functionally and morphologically at pressures up to 30 bar. Between 40 and 80 bar, reliable functional and morphological nerve regeneration occurred. Waterjet pressures up to 30 bar might be applied safely under clinical conditions. This technique might be well suited to separate intact peripheral nerves from adjacent tumor or scar tissue. Further studies will have to show the clinical relevance of these dissection qualities.

  3. Variation in rat sciatic nerve anatomy: implications for a rat model of neuropathic pain.

    PubMed

    Asato, F; Butler, M; Blomberg, H; Gordh, T

    2000-03-01

    We discovered a variation of rat sciatic nerve anatomy as an incidental finding during the anatomical exploration of the nerve lesion site in a rat neuropathic pain model. To confirm the composition and distribution of rat sciatic nerve, macroscopic anatomical investigation was performed in both left and right sides in 24 adult Sprague-Dawley rats. In all rats, the L4 and L5 spinal nerves were fused tightly to form the sciatic nerve. However, the L6 spinal nerve did not fuse with this nerve completely as a part of the sciatic nerve, but rather sent a thin branch to it in 13 rats (54%), whereas in the remaining 11 rats (46%), L6 ran separately along with the sciatic nerve. Also, the L3 spinal nerve sent a thin branch to the L4 spinal nerve or sciatic nerve in 6 rats (25%). We conclude that the components of sciatic nerve in Sprague-Dawley rats vary from L3 to L6; however, the major components are L4 and L5 macroscopically. This finding is in contrast to the standard textbooks of rat anatomy which describe the sciatic nerve as having major contributions from L4, L5, and L6.

  4. Relative longitudinal motion of the finger flexors, subsynovial connective tissue, and median nerve before and after carpal tunnel release in a human cadaver model.

    PubMed

    Yamaguchi, Taihei; Osamura, Naoki; Zhao, Chunfeng; An, Kai-Nan; Amadio, Peter C

    2008-01-01

    The normal gliding environment in the carpal tunnel is complex. The median nerve and flexor tendons are surrounded by a multilayered subsynovial tissue. To date, observations of the relative motions of the flexor tendon, median nerve and multilayered subsynovial tissue have been through a surgically released open carpal tunnel. The purpose of this study was to compare the motions of these tissues in an intact and open carpal tunnel. We measured the relative motion of the middle finger flexor digitorum superficialis tendon, its surrounding subsynovial connective tissue (SSCT) and the median nerve in 8 human cadavers. The flexor retinaculum was used as a fixed reference point. The motions were compared for simulated isolated middle finger and simulated fist motion as measured fluoroscopically in the closed carpal tunnel and directly in the open carpal tunnel. While the simulated isolated finger motion produced significantly less SSCT and median nerve motion (p<.05), there was no difference in flexor digitorum superficialis, SSCT, or nerve motion when comparing the fluoroscopic measurements in the closed carpal tunnel with the direct visual measurements in the open carpal tunnel. Relative motion of the flexor tendons, SSCT, and median nerve within the carpal tunnel follows a certain pattern, which may indicate the physiological state of the SSCT. This relative motion pattern was not affected by flexor retinaculum release.

  5. Determination of the median nerve residual latency values in the diagnosis of carpal tunnel syndrome in comparison with other electrodiagnostic parameters.

    PubMed

    Khosrawi, Saeid; Dehghan, Farnaz

    2013-11-01

    Along with conventional electrodiagnostic studies, several other indexes including residual latency (RL) were introduced in patients with different types of peripheral neuropathies. RL is the time difference between measured and predicted distal conduction times. This study was performed to determine the values of the median nerve RL and to investigate its sensitivity and specificity in the diagnosis of carpal tunnel syndrome (CTS). The study was carried out among 100 hands of 75 healthy volunteers and 64 patients who had a positive history of pain or paresthesia in upper extremities and 2 of 3 signs suggesting CTS. Information including age, gender and results of sensory and motor nerve conduction velocity, compound motor action potential of proximal and distal stimulation and RL were recorded for analysis. Normal range of the median nerve RL was found to be 1.03-2.65 (mean = 1.84 ± 0.41). The cut-off point of median RL was 2.37 for CTS diagnosis with sensitivity of 85.9% (95% of confidence interval [CI]: 84.4-87.5%) and specificity of 91.1% (95% CI: 87.8-92.2%). In mild cases of CTS, which conventional nerve conduction studies (NCSs) shows abnormalities only in sensory studies, RL may better demonstrate the effect on the median nerve motor fibers. We conclude that RL measurement of the median nerve may raise the sensitivity of NCSs for the diagnosis of CTS.

  6. Multichannel SEP-recording after paired median nerve stimulation suggests origin of paired-pulse inhibition rostral of the brainstem.

    PubMed

    Höffken, Oliver; Lenz, Melanie; Tegenthoff, Martin; Schwenkreis, Peter

    2010-01-14

    Paired-pulse techniques are a common tool to investigate the excitability of the cerebral cortex. Whereas in the motor system short interval intracortical inhibition assessed by paired-pulse transcranial magnetic stimulation clearly could be demonstrated to be generated within the motor cortex, the mechanism of paired-pulse inhibition measured over the somatosensory cortex after paired-pulse median nerve stimulation is less clear. The aim of this study was to further investigate the level of somatosensory processing where this paired-pulse inhibition is generated. We applied single and paired electrical stimulation of the median nerve with an interstimulus interval of 30ms. Somatosensory evoked potentials were recorded over the brachial plexus, the cranial cervical medulla and the primary somatosensory cortex. We analyzed peak-to-peak amplitudes evoked by the second stimulus of paired-pulse stimulation after digital subtraction of a single pulse (A2s), and referred it to the first response before linear subtraction (A1). Paired-pulse inhibition was expressed as a ratio (A2s/A1) of the amplitudes of the second (A2s) and the first (A1) peaks. We found a significant reduction of A2s as compared to A1 over S1, but no significant difference between A1 and A2s over brachial plexus and cranial medulla. In addition, the cortical amplitude ratio A2s/A1 was significantly reduced compared to the amplitude ratios over cranial medulla and brachial plexus. These results suggest that the underlying inhibitory mechanisms are generated rostral to the brainstem nuclei, probably due to the activity of thalamic or intracortical inhibitory interneurons. Copyright 2009 Elsevier Ireland Ltd. All rights reserved.

  7. Fibrolipomatous hamartoma of the median nerve: A cause of acute bilateral carpal tunnel syndrome in a three-year-old child: A case report and comprehensive literature review

    PubMed Central

    Senger, Jenna-Lynn; Classen, Dale; Bruce, Garth; Kanthan, Rani

    2014-01-01

    A three-year-old boy was investigated for inexplicable incessant crying. On examination, his left wrist was mildly swollen (three to four months) and sensitive. Exploration and carpal tunnel decompression of the left wrist with incisional biopsy was performed for the presence of a fusiform swelling intimately associated with the median nerve. Histopathology revealed the presence of enlarged nerve bundles admixed with mature fat cells and diffuse fibroblastic proliferation. Three months later, he underwent urgent contralateral carpal tunnel decompression for a similar presentation. The final diagnosis was bilateral fibrolipomatous hamartoma (FLH) of the median nerves causing acute bilateral compression neuropathy. FLH of the median nerve is an extremely unusual cause of acute bilateral carpal tunnel syndrome in a young child presenting with ‘incessant crying’. A comprehensive review of FLH including epidemiology, etiology, clinical presentation, differential diagnosis, imaging, pathology, treatment and prognosis is discussed. PMID:25332651

  8. N10 potential as an antidromic motor evoked potential in a median nerve short-latency somatosensory evoked potential study.

    PubMed

    Inoue, Ken; Mimori, Yasuyo; Nakamura, Shigenobu

    2002-01-01

    When stimulating the mixed nerve to record evoked potential, both sensory and motor fibers are activated before entering the spinal cord. The N10 potential has been described as an antidromic motor evoked potential based on results obtained by recording at the anterior midneck. In the present study, we examined the changes in latencies of Erb's potential, N10, and N13 by stimulating the median nerve distally at the wrist and proximally at the elbow. The conduction velocity of N10 calculated by the difference between N10 latencies at the two stimulation points was consistent with motor conduction velocity, although N13 conduction velocity estimated by the same method reflected a sensory conduction velocity. A positive relation was also observed between the indirect latency from the stimulation point to the anterior root as calculated using the equation (F - M - 1) / 2 (ms) and the direct latency to the negative peak of the N10 potential. Our data support the notion that N10 represents antidromic motor potential originating in the spinal entry zone of the anterior root.

  9. Assessment of the kinetic trajectory of the median nerve in the wrist by high-frequency ultrasound.

    PubMed

    Lin, Yi-Hsun; Hsieh, Mei-Yu; Su, Fong-Chin; Wang, Shyh-Hau

    2014-04-28

    Carpal tunnel syndrome (CTS) is typically diagnosed by physical examination or nerve conduction measurements. With these diagnostics however it is difficult to obtain anatomical information in the carpal tunnel. To further improve the diagnosis of CTS, an attempt using 30 MHz high-frequency ultrasound to noninvasively detect the local anatomical structures and the kinetic trajectory of the median nerve (MN) in the wrist was explored. Measurements were performed on the right wrist of 14 asymptomatic volunteers. The kinetic trajectory of the MN corresponding to flexion (from 0° to 90°) and extension (from 90° to 0°) movements of the fingers were detected by a cross correlation-based motion tracking technique. The average displacements of the MN according to finger movements were measured to be 3.74 and 2.04 mm for male and female subjects, respectively. Moreover, the kinetic trajectory of the MN in both the ulnar-palmar and total directions generally follows a sigmoidal curve tendency. This study has verified that the use of high-frequency ultrasound imaging and a motion tracking technique to sensitively detect the displacement and kinetic trajectory of the MN for the assessment of CTS patients is feasible.

  10. Median nerve stimulation prevents atrial electrical remodelling and inflammation in a canine model with rapid atrial pacing.

    PubMed

    Zhao, Qingyan; Zhang, Shudi; Zhao, Hongyi; Zhang, Shujuan; Dai, Zixuan; Qian, Yongsheng; Zhang, Youjing; Wang, Xi; Tang, Yanhong; Huang, Congxin

    2017-03-31

    Studies have shown that stellate ganglion nerve activity has association with atrial electrical remodelling and atrial fibrillation (AF) inducibility, while median nerve stimulation (MNS) decreases cardiac sympathetic drive. In this study, we tested the hypothesis that MNS suppresses atrial electrical remodelling and AF vulnerability. The atrial effective refractory period (AERP) and AF inducibility at baseline and after 3 h of rapid atrial pacing were determined in dogs undergoing MNS (n = 7), MNS+ application of methyllycaconitine (n = 7) or sham procedure (n = 6). Then, the levels of tumour necrosis factor-alpha (TNF-a), interleukin-6 (IL-6), and acetylcholine (Ach) in the plasma and atrial tissues were measured. The control dogs (n = 4) were assigned to measure atrial inflammation cytokines. Short-term rapid atrial pacing induced shortening of the AERP, an increase in AERP dispersion, and an increase AF vulnerability in the sham dogs, which were all suppressed by MNS. Levels of TNF-a and IL-6 were higher, and Ach levels were lower in the left and the right atrium in the sham dogs than in the MNS dogs. Methyllycaconitine blunted the effects of MNS on the AERP, AERP dispersion, the AF vulnerability, and TNF-a and IL-6 levels in the atrium, but had no impact on the levels of Ach. The effects of MNS on atrial electrical remodelling and AF inducibility might be associated with the cholinergic anti-inflammatory pathway.

  11. Assessment of the Kinetic Trajectory of the Median Nerve in the Wrist by High-Frequency Ultrasound

    PubMed Central

    Lin, Yi-Hsun; Hsieh, Mei-Yu; Su, Fong-Chin; Wang, Shyh-Hau

    2014-01-01

    Carpal tunnel syndrome (CTS) is typically diagnosed by physical examination or nerve conduction measurements. With these diagnostics however it is difficult to obtain anatomical information in the carpal tunnel. To further improve the diagnosis of CTS, an attempt using 30 MHz high-frequency ultrasound to noninvasively detect the local anatomical structures and the kinetic trajectory of the median nerve (MN) in the wrist was explored. Measurements were performed on the right wrist of 14 asymptomatic volunteers. The kinetic trajectory of the MN corresponding to flexion (from 0° to 90°) and extension (from 90° to 0°) movements of the fingers were detected by a cross correlation-based motion tracking technique. The average displacements of the MN according to finger movements were measured to be 3.74 and 2.04 mm for male and female subjects, respectively. Moreover, the kinetic trajectory of the MN in both the ulnar-palmar and total directions generally follows a sigmoidal curve tendency. This study has verified that the use of high-frequency ultrasound imaging and a motion tracking technique to sensitively detect the displacement and kinetic trajectory of the MN for the assessment of CTS patients is feasible. PMID:24787637

  12. The effect of time after shear injury on the subsynovial connective tissue and median nerve within the rabbit carpal tunnel.

    PubMed

    Vanhees, Matthias; Chikenji, Takako; Thoreson, Andrew R; Zhao, Chunfeng; Schmelzer, James D; Low, Philip A; An, Kai-Nan; Amadio, Peter C

    2013-03-01

    The most prominent nonneurological finding in the common compression neuropathy carpal tunnel syndrome (CTS) is fibrosis of the subsynovial connective tissue (SSCT). Recently, a rabbit model of CTS has been developed, based on the hypothesis that SSCT injury and subsequent fibrosis cause nerve compression. The purpose of this study was to evaluate the effects in this model at earlier and later time points than have heretofore been reported. Sixty rabbits were operated on and observed at two different time periods: 6 and 24 weeks. Nerve electrophysiology (EP), SSCT histology, and SSCT mechanical properties were assessed. There was no significant difference in median motor nerve amplitude or latency at either time point. The total cell density in the SSCT was significantly higher at 6 and 24 weeks compared to controls. The mean size of the collagen fibrils in the SSCT was higher 6 and 24 weeks after surgery compared to controls. Both the ultimate load and the total energy absorption of the SSCT were significantly higher at 6 and 24 weeks compared to controls. In this model, there were signs of SSCT fibrosis and histology changes at 6 weeks, which persist after 24 weeks. Thus, this model leads to sustained SSCT fibrosis, which is one characteristic of human CTS. However, no significant EP changes were found at these two time points, which is in contrast to the findings reported previously for this model at 12 weeks. The significance of the differences in EP findings will be the subject of future studies.

  13. The role of median nerve terminal latency index in the diagnosis of carpal tunnel syndrome in comparison with other electrodiagnostic parameters.

    PubMed

    Vahdatpour, Babak; Khosrawi, Saeid; Chatraei, Maryam

    2016-01-01

    Carpal tunnel syndrome (CTS) considers the most common compression neuropathy, which nerve conduction studies (NCSs) used for its detection routinely and universally. This study was performed to determine the value of the median TLI and other NCS variables and to investigate their sensitivity and specificity in the diagnosis of CTS. The study was carried out among 100 hands of healthy volunteers and 50 hands of patients who had a positive history of paresthesia and numbness in upper extremities. Information including age, gender, and result of sensory and motor nerve conduction velocity (MNCV), peak latency difference of median and ulnar nerves of fourth digit (M4-U4 peak latency difference), and TLI were recorded for analysis. Sensitivity and specificity of electro diagnostic parameters in the diagnosis of CTS was investigated. Normal range of the median nerve TLI was 0.43 ± 0.077. There was no significant difference between two groups for MNCV means (P = 0. 45). Distal sensory latency and distal motor latency (DML) of median nerve and fourth digit median-ulnar peak latency differences (PM4-PU4) for CTS group was significantly higher (P < 0.001) and mean for sensory nerve conduction velocity was significantly higher in control group (P < 0.001). The most sensitive electrophysiological finding in CTS patients was median TLI (82%), but the most specific one was DML (98%). Although in early stages of CTS, we usually expect only abnormalities in the sensory studies, but TLI may better demonstrate the effect on median nerve motor fiber even in mild cases of CTS.

  14. The ulnar test: a method for the quantitative functional assessment of posttraumatic ulnar nerve recovery in the rat.

    PubMed

    Papalia, Igor; Tos, Pierluigi; Scevola, Anna; Raimondo, Stefania; Geuna, Stefano

    2006-06-30

    The assessment of recovery of the neuromuscular function following nerve lesion and repair is one of the main goals of peripheral nerve researchers. The forelimb model has recently seen an increase in its employment for experimental nerve repair studies especially because of the availability of the grasping test for assessing the functional recovery of one of its major nerves, the median nerve. Nerve repair studies sometimes require the use of more than one nerve to simulate severe clinical situations and, in this case, the ulnar nerve is often used together with the median nerve. However, a test for assessing ulnar nerve functional recovery is yet not available. To fill this gap, we have developed and experimentally tested a method for the functional assessment of posttraumatic ulnar nerve recovery in the rat. Animal testing using this method is simple, quick and provides the animal with minimal distress. The method proved to be effective in detecting the date on which recovery starts after ulnar nerve impairment and in following its improvement, over time. The availability of this new test is expected to further increase the employment of forelimb experimental nerve models instead of the more disabling hindlimb models.

  15. Ultrasound measurement of median nerve cross-sectional area at the inlet and outlet of carpal tunnel after carpal tunnel release compared to electrodiagnostic findings.

    PubMed

    Inui, Atsuyuki; Nishimoto, Hanako; Mifune, Yutaka; Kokubu, Takeshi; Sakata, Ryosuke; Kurosaka, Masahiro

    2016-09-01

    Ultrasound measurement of the cross-sectional area (CSA) of the median nerve can give information about regeneration of the nerve after carpal tunnel release (CTR), but the changes at selected follow-up points up to 1 year compared to electrodiagnostic findings are not known. We postoperatively measured the CSA of the median nerve with ultrasound and compared the measurements with electrophysiological findings over 12 months after open CTR. In 21 hands that underwent open CTR, the CSA of the median nerve was measured at the inlet (proximal CSA) and outlet (distal CSA) of the carpal tunnel at 3- 6- and 12-month follow-up. The respective ratios [(CSA postoperatively/CSA preoperatively) × 100] were calculated and correlated with distal motor latency (DML) and sensory nerve conduction velocity (SCV). The proximal CSA ratio was 88.9, 84.5, and 78.4 % at 3-, 6-, and 12-month follow-up, respectively. Each value was significantly lower than that before surgery. The distal CSA ratio was 104.3, 99.1, and 91.8 % at 3-, 6-, and 12-month follow-up, respectively. The values were not significantly different compared to preoperative values. The proximal CSA of the median nerve decreased continuously over the time after CTR while the distal CSA increased up to 3 months before it decreased continuously, too.

  16. Transverse plane tendon and median nerve motion in the carpal tunnel: ultrasound comparison of carpal tunnel syndrome patients and healthy volunteers.

    PubMed

    van Doesburg, Margriet H M; Henderson, Jacqueline; Mink van der Molen, Aebele B; An, Kai-Nan; Amadio, Peter C

    2012-01-01

    The median nerve and flexor tendons are known to translate transversely in the carpal tunnel. The purpose of this study was to investigate these motions in differential finger motion using ultrasound, and to compare them in healthy people and carpal tunnel syndrome patients. Transverse ultrasounds clips were taken during fist, index finger, middle finger and thumb flexion in 29 healthy normal subjects and 29 CTS patients. Displacement in palmar-dorsal and radial-ulnar direction was calculated using Analyze software. Additionally, the distance between the median nerve and the tendons was calculated. We found a changed motion pattern of the median nerve in middle finger, index finger and thumb motion between normal subjects and CTS patients (p<0.05). Also, we found a changed motion direction in CTS patients of the FDS III tendon in fist and middle finger motion, and of the FDS II and flexor pollicis longus tendon in index finger and thumb motion, respectively (p<0.05). The distance between the median nerve and the FDS II or FPL tendon is significantly greater in patients than in healthy volunteers for index finger and thumb motion, respectively (p<0.05). Our results suggest a changed motion pattern of the median nerve and several tendons in carpal tunnel syndrome patients compared to normal subjects. Such motion patterns may be useful in distinguishing affected from unaffected individuals, and in studies of the pathomechanics of carpal tunnel syndrome.

  17. Comparison of Median Nerve Cross-sectional Area on 3-T MRI in Patients With Carpal Tunnel Syndrome.

    PubMed

    Ikeda, Mikinori; Okada, Mitsuhiro; Toyama, Masahiko; Uemura, Takuya; Takamatsu, Kiyohito; Nakamura, Hiroaki

    2017-01-01

    This study correlated morphologic abnormalities of idiopathic carpal tunnel syndrome (CTS) with the severity of CTS using 3-T magnetic resonance imaging (MRI). The relationship of the severity of CTS and the cross-sectional area of the median nerve (CSA) was assessed at several levels. Seventy wrists of 35 patients (27 women and 8 men) with unilateral idiopathic CTS underwent nerve conduction study and 3-T MRI of the wrist. The CSA at 4 levels (distal radioulnar joint, body of scaphoid, tubercule of scaphoid, and hook of hamate) and the thickness of the transverse carpal ligament at 3 levels in both affected and unaffected hands were measured using 3-T MRI and correlated with the severity of CTS assessed with distal motor latency. The CSA in the affected hand at the scaphoid body level was significantly higher than in the unaffected hand. The CSA at the scaphoid body level was positively correlated with distal motor latency in the affected hand. The CSA in the affected hand at the scaphoid tubercule level was significantly lower than in the unaffected hand. The CSA had a negative correlation with distal motor latency at the scaphoid tubercule level. The CSA at the distal radioulnar joint and the hamate hook was not significantly different between the affected hand and the unaffected hand. The CSA at the distal radioulnar joint level and hook level were not correlated significantly with distal motor latency in the affected hand. The mean CSA of the affected hand at the scaphoid body level was highest in 4 levels. [Orthopedics. 2017; 40(1):e77-e81.]. Copyright 2016, SLACK Incorporated.

  18. Does the median preoptic nucleus contribute to sympathetic hyperactivity in spontaneously hypertensive rats?

    PubMed

    Mourão, Aline A; Moreira, Marina C S; Melo, Aryanne B S; Lopes, Paulo R; Rebelo, Ana C S; Rosa, Daniel A; Freiria-Oliveira, André H; Colombari, Eduardo; Pedrino, Gustavo R

    2016-02-01

    The present study sought to determine the involvement of median preoptic nucleus (MnPO) in the regulation of the cardiovascular function and renal sympathetic activity in normotensive (NT) and spontaneously hypertensive rats (SHR). MnPO inhibition evoked by Muscimol (4mM) nanoinjections, elicited fall in MAP and renal sympathoinhibition in NT-rats. Surprisingly, in SHRs these responses were greater than in NT-rats. These results demonstrated, for the first time that MnPO was involved in the tonic control of sympathetic activity in NT and SHRs. Furthermore, our data suggest the MnPO involvement in the increased sympathetic outflow and consequent arterial hypertension observed in SHRs.

  19. Human cortical potentials evoked by stimulation of the median nerve. II. Cytoarchitectonic areas generating long-latency activity.

    PubMed

    Allison, T; McCarthy, G; Wood, C C; Williamson, P D; Spencer, D D

    1989-09-01

    1. The anatomic generators of human median nerve somatosensory evoked potentials (SEPs) in the 40 to 250-ms latency range were investigated in 54 patients by means of cortical-surface and transcortical recordings obtained during neurosurgery. 2. Contralateral stimulation evoked three groups of SEPs recorded from the hand representation area of sensorimotor cortex: P45-N80-P180, recorded anterior to the central sulcus (CS) and maximal on the precentral gyrus; N45-P80-N180, recorded posterior to the CS and maximal on the postcentral gyrus; and P50-N90-P190, recorded near and on either side of the CS. 3. P45-N80-P180 inverted in polarity to N45-P80-N180 across the CS but was similar in polarity from the cortical surface and white matter in transcortical recordings. These spatial distributions were similar to those of the short-latency P20-N30 and N20-P30 potentials described in the preceding paper, suggesting that these long-latency potentials are generated in area 3b of somatosensory cortex. 4. P50-N90-P190 was largest over the anterior one-half of somatosensory cortex and did not show polarity inversion across the CS. This spatial distribution was similar to that of the short-latency P25-N35 potentials described in the preceding paper and, together with our and Goldring et al. 1970; Stohr and Goldring 1969 transcortical recordings, suggest that these long-latency potentials are generated in area 1 of somatosensory cortex. 5. SEPs of apparently local origin were recorded from several regions of sensorimotor cortex to stimulation of the ipsilateral median nerve. Surface and transcortical recordings suggest that the ipsilateral potentials are generated not in area 3b, but rather in other regions of sensorimotor cortex perhaps including areas 4, 1, 2, and 7. This spatial distribution suggests that the ipsilateral potentials are generated by transcallosal input from the contralateral hemisphere. 6. Recordings from the periSylvian region were characterized by P100 and N

  20. Human cortical potentials evoked by stimulation of the median nerve. I. Cytoarchitectonic areas generating short-latency activity.

    PubMed

    Allison, T; McCarthy, G; Wood, C C; Darcey, T M; Spencer, D D; Williamson, P D

    1989-09-01

    1. The anatomic generators of human median nerve somatosensory evoked potentials (SEPs) in the 40 to 250-ms latency range were investigated in 54 patients by means of cortical-surface and transcortical recordings obtained during neurosurgery. 2. Contralateral stimulation evoked three groups of SEPs recorded from the hand representation area of sensorimotor cortex: P45-N80-P180, recorded anterior to the central sulcus (CS) and maximal on the precentral gyrus; N45-P80-N180, recorded posterior to the CS and maximal on the postcentral gyrus; and P50-N90-P190, recorded near and on either side of the CS. 3. P45-N80-P180 inverted in polarity to N45-P80-N180 across the CS but was similar in polarity from the cortical surface and white matter in transcortical recordings. These spatial distributions were similar to those of the short-latency P20-N30 and N20-P30 potentials described in the preceding paper, suggesting that these long-latency potentials are generated in area 3b of somatosensory cortex. 4. P50-N90-P190 was largest over the anterior one-half of somatosensory cortex and did not show polarity inversion across the CS. This spatial distribution was similar to that of the short-latency P25-N35 potentials described in the preceding paper and, together with our and Goldring et al. 1970; Stohr and Goldring 1969 transcortical recordings, suggest that these long-latency potentials are generated in area 1 of somatosensory cortex. 5. SEPs of apparently local origin were recorded from several regions of sensorimotor cortex to stimulation of the ipsilateral median nerve. Surface and transcortical recordings suggest that the ipsilateral potentials are generated not in area 3b, but rather in other regions of sensorimotor cortex perhaps including areas 4, 1, 2, and 7. This spatial distribution suggests that the ipsilateral potentials are generated by transcallosal input from the contralateral hemisphere. 6. Recordings from the periSylvian region were characterized by P100 and N

  1. The rat caudal nerves: a model for experimental neuropathies.

    PubMed

    Schaumburg, Herbert H; Zotova, Elena; Raine, Cedric S; Tar, Moses; Arezzo, Joseph

    2010-06-01

    This study provides a detailed investigation of the anatomy of the rat caudal nerve along its entire length, as well as correlated nerve conduction measures in both large and small diameter axons. It determines that rodent caudal nerves provide a simple, sensitive experimental model for evaluation of the pathophysiology of degeneration, recovery, and prevention of length-dependent distal axonopathy. After first defining the normal anatomy and electrophysiology of the rat caudal nerves, acrylamide monomer, a reliable axonal toxin, was administered at different doses for escalating time periods. Serial electrophysiological recordings were obtained, during intoxication, from multiple sites along caudal and distal sciatic nerves. Multiple sections of the caudal and sciatic nerves were examined with light and electron microscopy. The normal distribution of conduction velocities was determined and acrylamide-induced time- and dose-related slowing of velocities at the vulnerable ultraterminal region was documented. Degenerative morphological changes in the distal regions of the caudal nerves appeared well before changes in the distal sciatic nerves. Our study has shown that (1) rat caudal nerves have a complex neural structure that varies along a distal-to-proximal gradient and (2) correlative assessment of both morphology and electrophysiology of rat caudal nerves is easily achieved and provides a highly sensitive index of the onset and progression of the length-dependent distal axonopathy.

  2. Lipofibromatous hamartoma of the median nerve in patients with macrodactyly: diagnosis and treatment of a rare disease causing carpal tunnel syndrome.

    PubMed

    Ulrich, Dietmar; Ulrich, Franziska; Schroeder, Michael; Pallua, Norbert

    2009-09-01

    Lipofibromatous hamartoma is a very rare benign peripheral nerve tumour. It is mostly encountered in the proximal extremities of young adults, involving the median nerve in the majority of cases. We present two patients with macrodactyly and carpal tunnel syndrome caused by lipofibromatous hamartoma of the median nerve and discuss diagnosis and treatment of the disease. A 10-year-old girl with a congenital progressive macrodactyly of her right index finger presented with a slowly growing mass in her right palm and pain and numbness, along with motor and sensory deficits in the median nerve distribution. Treatment consisted of carpal tunnel release, epineurolysis and partial excision of the fibrofatty tissue. The second patient, a 25-year-old man presented with a swelling in his left palm and findings compatible with carpal tunnel syndrome. Intraoperatively, the lesion presented as sausage-shaped enlargement of the median nerve by fibrofatty tissue. After carpal tunnel release, a partial excision of the mass with epineurolysis was performed. In both patients, histology showed nerve bundles separated by abundant fibrofatty tissue. In the girl, a proliferation of dysplastic perineurial cells could be observed. The suspected diagnosis for patients with macrodactyly and clinical signs of carpal tunnel syndrome should be lipofibromatous hamartoma. A carefully taken history, physical examination, X-ray, and MRI are important for its correct diagnosis. The surgical management remains controversial. Treatment should include decompression of the median nerve at points of compression, partial excision of the fibrofatty tissue, and debulking of soft tissue. In some cases, an epineurolysis can be additionally performed.

  3. Ultrasound for diagnosis of carpal tunnel syndrome: comparison of different methods to determine median nerve volume and value of power Doppler sonography.

    PubMed

    Dejaco, Christian; Stradner, Martin; Zauner, Dorothea; Seel, Werner; Simmet, Nicole Elisabeth; Klammer, Alexander; Heitzer, Petra; Brickmann, Kerstin; Gretler, Judith; Fürst-Moazedi, Florentine C; Thonhofer, Rene; Husic, Rusmir; Hermann, Josef; Graninger, Winfried B; Quasthoff, Stefan

    2013-12-01

    To compare ultrasound measurement of median nerve cross-sectional area (CSA) at different anatomical landmarks and to assess the value of power Doppler signals within the median nerve for diagnosis of carpal tunnel syndrome (CTS). A prospective study of 135 consecutive patients with suspected CTS undergoing two visits within 3 months. A final diagnosis of CTS was established by clinical and electrophysiological findings. CSA was sonographically measured at five different levels at forearm and wrist; and CSA wrist to forearm ratios or differences were calculated. Intraneural power Doppler signals were semiquantitatively graded. Diagnostic values of different ultrasound methods were compared by receiver operating characteristic curves using SPSS. CTS was diagnosed in 111 (45.5%) wrists; 84 (34.4%) had no CTS and 49 (20.1%) were possible CTS cases. Diagnostic values were comparable for all sonographic methods to determine median nerve swelling, with area under the curves ranging from 0.75 to 0.85. Thresholds of 9.8 and 13.8 mm(2) for the largest CSA of the median nerve yielded a sensitivity of 92% and a specificity of 92%. A power Doppler score of 2 or greater had a specificity of 90% for the diagnosis of CTS. Sonographic median nerve volumetry revealed a good reliability with an intraclass correlation coefficient of 0.90 (95% CI 0.79 to 0.95). Sonographic assessment of median nerve swelling and vascularity allows for a reliable diagnosis of CTS. Determination of CSA at its maximal shape offers an easily reproducible tool for CTS classification in daily clinical practice.

  4. Transverse Ultrasound Assessment of the Displacement of the Median Nerve in the Carpal Tunnel during Wrist and Finger Motion in Healthy Volunteers.

    PubMed

    Nanno, Mitsuhiko; Sawaizumi, Takuya; Kodera, Norie; Tomori, Yuji; Takai, Shinro

    2015-01-01

    The purpose of this study was to investigate the displacement of the median nerve in the carpal tunnel during finger motion at varied wrist positions using transverse ultrasound in healthy volunteers, in order to clarify the appropriate position of a wrist splint in treating carpal tunnel syndrome. Fifty wrists of 25 asymptomatic volunteers were evaluated by transverse ultrasound. The location of the median nerve in the carpal tunnel was examined at 5 wrist positions (neutral, 60° dorsiflexion, 60° palmar flexion, 40° ulnar flexion, 10° radial flexion) with all 5 fingers in full extension, all 5 fingers in full flexion, and isolated thumb in full flexion, respectively. The median nerve was located significantly (p<0.05) more dorsally at the wrist dorsal flexion position, more ulnopalmarly at the wrist palmar flexion position, more radially at the wrist radial flexion position, and more radially at the wrist ulnar flexion position than at the wrist neutral position in all 5 fingers at full extension. The median nerve moved the most significantly dorsally among all wrist positions during finger motion at the wrist dorsal flexion position (p<0.05). Conversely, the median nerve moved the most significantly ulnopalmarly at the wrist palmar flexion position with all 5 fingers in full flexion among all wrist positions during finger motion (p<0.05). This latter wrist and finger position induced significant displacement of the median nerve toward the transverse carpal ligament, and compressed it between the flexor tendons and the transverse carpal ligament. This study showed that there is a significant relationship between the median nerve displacement in the carpal tunnel and the motion of the wrist and fingers. This finding suggests that the compression or the shearing stress of the median nerve caused by the movement of the flexor tendons is reduced in the wrist dorsal flexion position compared with other wrist positions. This wrist dorsal flexion position could be

  5. Presence or absence of palmaris longus and fifth superficial flexor digitorum; is there any effect on median nerve surface area in wrist sonography.

    PubMed

    Enhesari, Ahmad; Saied, Alireza; Mohammadpoor, Lotfollah; Ayatollahi Mousavi, Alia; Arabnejhad, Fateme

    2014-12-01

    Carpal tunnel syndrome (CTS) describes a set of symptoms caused by compression of the median nerve in the wrist, which is the most common site of nerve compression in the upper limb. This syndrome is a primary source of pain and reduced function in these patients, and the cause is compression of the median nerve where it passes beneath the flexor retinaculum in the wrist. The aim of the present cross sectional study is to assess the absence of palmaris longus and fifth superficial flexor digitorum tendon as normal anatomic variations on the sonographic measurement of median nerve surface area in healthy individuals' wrists. Ninety-three healthy volunteers underwent clinical evaluation for determining the presence of tendons in both wrists and sonographic measurement of median nerve surface area. In 41 of 186 (22%) hands, the palmaris longus tendon was absent and absence of the fifth flexor digitorum tendon was noted in eight (4.30 %). The median surface area in the hands without palmaris longus was meaningfully lower than the hands with it (P = 0.025), while the difference in the median surface area was not statistically significant with regard to presence of the fifth flexor digitorum tendon (P = 0.324). Based upon the findings of the present study, it seems that the median surface area as a sonographic finding is probably related to presence or absence of the palmaris longus tendon, so that hands with the tendon present have larger surface areas. In addition, it seems that this sonographic finding does not depend on the function of the fifth superficial flexor digitorum tendon. Therefore, no correlation between CTS and the presence of palmaris longus tendon should be observed.

  6. The effects of stimulus rates on the amplitude of median nerve somatosensory evoked potentials: the developmental change.

    PubMed

    Araki, A; Takada, A; Yasuhara, A; Kobayashi, Y

    1999-03-01

    We examined the effects of stimulus rates on the somatosensory evoked potential (SEP) amplitudes following median nerve stimulation at the wrist in 42 children. We divided these subjects into five groups according to their age (0-6 months, 7-12 months, 1-3 years, 4-6 years and more than 7 years) and measured the peak-to-peak amplitude of every component (N9, P10, N11, P13/14, N18, N20, P23, N30) at stimulus rates of 1.0, 3.5 and 5.5 Hz. From N9 to N18, there was no significant change in amplitude nor latency with stimulus rate change in all groups. The amplitude attenuation was found at the N20 and N30 peaks in the young group (0 months to 3 years) and at P23 in all groups with an increasing stimulus rate. The attenuation rate of P23 amplitude was influenced by the age of subjects, being greater in younger groups and greatest in the youngest group (0-6 months). The differences of amplitude attenuation rate between this group and the rest were statistically significant. The results of this study indicate that the amplitudes of the cortical components of SEP in children are greatly influenced by the stimulus rate. Thus when we discuss the amplitude of cortical waves in childhood, we should also pay attention to the stimulus rates.

  7. The effect of tendon excursion velocity on longitudinal median nerve displacement: differences between carpal tunnel syndrome patients and controls.

    PubMed

    Filius, Anika; Thoreson, Andrew R; Wang, Yuexiang; Passe, Sandra M; Zhao, Chunfeng; An, Kai-Nan; Amadio, Peter C

    2015-04-01

    The subsynovial connective tissue (SSCT) is a viscoelastic structure connecting the median nerve (MN) and the flexor tendons in the carpal tunnel. Increased strain rates increases stiffness in viscoelastic tissues, and thereby its capacity to transfer shear load. Therefore, tendon excursion velocity may impact the MN displacement. In carpal tunnel syndrome (CTS) the SSCT is fibrotic and may be ruptured, and this may affect MN motion. In this study, ultrasonography was performed on 14 wrists of healthy controls and 25 wrists of CTS patients during controlled finger motions performed at three different velocities. Longitudinal MN and tendon excursion were assessed using a custom speckle tracking algorithm and compared across the three different velocities. CTS patients exhibited significantly less MN motion than controls (p ≤ 0.002). While in general, MN displacement increased with increasing tendon excursion velocity (p ≤ 0.031). These findings are consistent with current knowledge of SSCT mechanics in CTS, in which in some patients the fibrotic SSCT appears to have ruptured from the tendon surface. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  8. Neuromuscular electrical stimulation of the median nerve facilitates low motor cortex excitability in patients with spinocerebellar ataxia.

    PubMed

    Chen, Chih-Chung; Chuang, Yu-Fen; Yang, Hsiao-Chu; Hsu, Miao-Ju; Huang, Ying-Zu; Chang, Ya-Ju

    2015-02-01

    The neuromodulation of motor excitability has been shown to improve functional movement in people with central nervous system damage. This study aimed to investigate the mechanism of peripheral neuromuscular electrical stimulation (NMES) in motor excitability and its effects in people with spinocerebellar ataxia (SCA). This single-blind case-control study was conducted on young control (n=9), age-matched control (n=9), and SCA participants (n=9; 7 SCAIII and 2 sporadic). All participants received an accumulated 30 min of NMES (25 Hz, 800 ms on/800 ms off) of the median nerve. The central motor excitability, measured by motor evoked potential (MEP) and silent period, and the peripheral motor excitability, measured by the H-reflex and M-wave, were recorded in flexor carpi radialis (FCR) muscle before, during, and after the NMES was applied. The results showed that NMES significantly enhanced the MEP in all 3 groups. The silent period, H-reflex and maximum M-wave were not changed by NMES. We conclude that NMES enhances low motor excitability in patients with SCA and that the mechanism of the neuromodulation was supra-segmental. These findings are potentially relevant to the utilization of NMES for preparation of motor excitability. The protocol was registered at Clinicaltrials.gov (NCT02103075). Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  9. Perineural Dexmedetomidine as an Adjuvant Reduces the Median Effective Concentration of Lidocaine for Obturator Nerve Blocking: A Double-Blinded Randomized Controlled Trial.

    PubMed

    Lu, Yuechun; Sun, Jian; Zhuang, Xinqi; Lv, Guoyi; Li, Yize; Wang, Haiyun; Wang, Guolin

    2016-01-01

    Research suggests that the addition of dexmedetomidine to local anesthetics can prolong peripheral nerve blocks; however, it is not known whether dexmedetomidine can reduce the quantity of local anesthetic needed. We hypothesized that adding dexmedetomidine as an adjuvant to an obturator nerve block could reduce the median effective concentration of lidocaine. In this double-blinded randomized trial, 60 patients scheduled for elective transurethral resection of bladder tumors on the lateral wall were randomly divided into two groups: the control group (C group, n = 30) and the dexmedetomidine group (D group, n = 30). Two main branches of the obturator nerve (i.e., anterior and posterior) were identified using neural stimulation at the inguinal level, with only lidocaine used for the C group and 1 μg/kg dexmedetomidine combined with lidocaine used for the D group. The median effective concentration was determined by an up-and-down sequential trial. The ratio of two consecutive concentrations was 1.2. The median effective concentration (95% confidence interval) of lidocaine was 0.57% (0.54%-0.62%) in the C group and 0.29% (0.28%-0.38%) in the D group. The median effective concentration of lidocaine was significantly lower in the D group than in the C group (p < 0.05). These results indicate that dexmedetomidine (1 μg/kg) in combination with lidocaine for obturator nerve block decreases the median effective concentration of lidocaine. ClinicalTrials.gov NCT02066727.

  10. Does the ratio of the carpal tunnel inlet and outlet cross-sectional areas in the median nerve reflect carpal tunnel syndrome severity?

    PubMed Central

    Zhang, Li; Rehemutula, Aierken; Peng, Feng; Yu, Cong; Wang, Tian-bin; Chen, Lin

    2015-01-01

    Although ultrasound measurements have been used in previous studies on carpal tunnel syndrome to visualize injury to the median nerve, whether such ultrasound data can indicate the severity of carpal tunnel syndrome remains controversial. The cross-sectional areas of the median nerve at the tunnel inlet and outlet can show swelling and compression of the nerve at the carpal. We hypothesized that the ratio of the cross-sectional areas of the median nerve at the carpal tunnel inlet to outlet accurately reflects the severity of carpal tunnel syndrome. To test this, high-resolution ultrasound with a linear array transducer at 5–17 MHz was used to assess 77 patients with carpal tunnel syndrome. The results showed that the cut-off point for the inlet-to-outlet ratio was 1.14. Significant differences in the inlet-to-outlet ratio were found among patients with mild, moderate, and severe carpal tunnel syndrome. The cut-off point in the ratio of cross-sectional areas of the median nerve was 1.29 between mild and more severe (moderate and severe) carpal tunnel syndrome patients with 64.7% sensitivity and 72.7% specificity. The cut-off point in the ratio of cross-sectional areas of the median nerve was 1.52 between the moderate and severe carpal tunnel syndrome patients with 80.0% sensitivity and 64.7% specificity. These results suggest that the inlet-to-outlet ratio reflected the severity of carpal tunnel syndrome. PMID:26330845

  11. Effects of Alcohol Injection in Rat Sciatic Nerve

    PubMed Central

    Mazoch, Mathew J.; Cheema, Gulraiz A.; Suva, Larry J.; Thomas, Ruth L.

    2015-01-01

    Background Previous studies have shown that the injection of dehydrated alcohol has been successful for the treatment of Morton's neuroma in the foot. In this study, we determined the cellular effect of injection of alcohol into and around the sciatic nerve of rats, and measured the extent of cell necrosis and/or any associated histologic or inflammatory changes. Methods Twenty-two male (~375g) Wistar rats were randomized into two groups each receiving alcohol injections into or around the sciatic nerve after nerve exposure under sterile technique. Group 1 rats were injected with a 0.5ml solution of 0.5% Marcaine in the left sciatic nerve as a control group. In the right sciatic nerve a 0.5ml solution of 4% ethanol with 0.5% Marcaine was injected. Group 2 rats received 0.5ml of 20%ethanol with 0.5% Marcaine injected into the left sciatic nerve and 0.5 ml of 30% ethanol with 0.5% Marcaine injected into the right sciatic nerve. In each group, the rats were placed in 3 subgroups: intraneural, perineural, perimuscular injections. All rats were sacrificed and tissue harvested for histologic evaluation at day 10 post injection. Results No evidence of alcohol-associated cell necrosis, apoptosis or apparent inflammation was observed in histologic specimens of any injected nerves, perineural tissue, or muscles in controls or experimental groups regardless of concentration of ethanol injected on day 10. Conclusion We concluded that alcohol injection (≤30% ethanol) into and/or around the sciatic nerve or the adjacent muscle of rats has no histologic evidence of necrosis or inflammation to the nerve or surrounding tissue. There was no observable histological change in apoptosis, or cell number, in response to the alcohol injection. PMID:25097192

  12. The Prevalence of Anatomical Variations of the Median Nerve in the Carpal Tunnel: A Systematic Review and Meta-Analysis

    PubMed Central

    Roy, Joyeeta; Vikse, Jens; Ramakrishnan, Piravin Kumar; Walocha, Jerzy A.; Tomaszewski, Krzysztof A.

    2015-01-01

    Background and Objective The course and branches of the median nerve (MN) in the wrist vary widely among the population. Due to significant differences in the reported prevalence of such variations, extensive knowledge on the anatomy of the MN is essential to avoid iatrogenic nerve injury. Our aim was to determine the prevalence rates of anatomical variations of the MN in the carpal tunnel and the most common course patterns and variations in its thenar motor branch (TMB). Study Design A systematic search of all major databases was performed to identify articles that studied the prevalence of MN variations in the carpal tunnel and the TMB. No date or language restrictions were set. Extracted data was classified according to Lanz's classification system: variations in the course of the single TMB—extraligamentous, subligamentous, and transligamentous (type 1); accessory branches of the MN at the distal carpal tunnel (type 2); high division of the MN (type 3); and the MN and its accessory branches proximal to the carpal tunnel (type 4). Pooled prevalence rates were calculated using MetaXL 2.0. Results Thirty-one studies (n = 3918 hands) were included in the meta-analysis. The pooled prevalence rates of the extraligamentous, subligamentous, and transligamentous courses were 75.2% (95%CI:55.4%-84.7%), 13.5% (95%CI:3.6%-25.7%), and 11.3% (95%CI:2.4%-23.0%), respectively. The prevalence of Lanz group 2, 3, and 4 were 4.6% (95%CI:1.6%-9.1%), 2.6% (95%CI:0.1%-2.8%), and 2.3% (95%CI:0.3%-5.6%), respectively. Ulnar side of branching of the TMB was found in 2.1% (95%CI:0.9%-3.6%) of hands. The prevalence of hypertrophic thenar muscles over the transverse carpal ligament was 18.2% (95%CI:6.8%-33.0%). A transligamentous course of the TMB was more commonly found in hands with hypertrophic thenar muscles (23.4%, 95%CI:5.0%-43.4%) compared to those without hypertrophic musculature (1.7%, 95%CI:0%-100%). In four studies (n = 423 hands), identical bilateral course of the TMB was

  13. Repeatability and Minimal Detectable Change in Longitudinal Median Nerve Excursion Measures During Upper Limb Neurodynamic Techniques in a Mixed Population: A Pilot Study Using Musculoskeletal Ultrasound Imaging.

    PubMed

    Paquette, Philippe; Lamontagne, Martin; Higgins, Johanne; Gagnon, Dany H

    2015-07-01

    This study determined test-retest reliability and minimum detectable change in longitudinal median nerve excursion during upper limb neurodynamic tests (ULNTs). Seven participants with unilateral or bilateral carpal tunnel syndrome and 11 healthy participants were randomly tested with two ULNTs (i.e., tensioner and slider). Each ULNT was performed three times each at 45° and 90° of shoulder abduction on two separate visits. Video sequences of median nerve excursion, recorded by a physical therapist using ultrasound imaging, were quantified using computer software. The generalizability theory, encompassing a G-Study and a D-study, measured the dependability coefficient (Φ) along with standard error of measurement (SEM) accuracy and allowed various testing protocols to be proposed. The highest reliability (Φ = 0.84) and lowest minimal measurement error (SEM = 0.58 mm) of the longitudinal median nerve excursion were reached during the ULNT-slider performed with 45° of shoulder abduction and when measures obtained from three different image sequences recorded during a single visit were averaged. It is recommended that longitudinal median nerve excursion measures computed from three separate image sequences recorded during a single visit be averaged in clinical practice. Ideally, adding a second visit (six image sequences) is also suggested in research protocols. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  14. BOLD-fMRI with median nerve electrical stimulation predict hemodynamic improvement after revascularization in patients with moyamoya disease.

    PubMed

    Qiao, Peng-Gang; Han, Cong; Qian, Tianyi; Li, Gong-Jie; Yin, Hong

    2017-10-01

    To assess the severity of cerebral hemodynamic impairment and hemodynamic improvements, after revascularization in moyamoya disease (MMD) by means of blood-oxygen-level dependent functional magnetic resonance imaging (BOLD-fMRI). BOLD-fMRI with median nerve electrical stimulation based on echo planar imaging was performed in 73 volunteers with MMD and 15 healthy volunteers using a 3.0 Tesla MRI scanner. Twenty-four MMD patients were reexamined after encephaloduroarteriosynangiosis. Time-signal intensity curves of the activated area of the contralateral primary somatosensory cortex were computed. Negative response time (Tnr) and peak (Pnr), positive response time (Tpr) and peak (Ppr), and time to negative peak (TTPn) and positive peak (TTPp) were measured. Compared with nonparesthesia group and the asymptomatic side of paresthesia group, the patients with paresthesia showed extended Tnr (22.04 ± 3.34 s versus 9.57 ± 2.27 s and 12.67 ± 2.69 s, P = 0.0096), decreased Pnr (-0.47 ± 0.06 versus -0.30 ± 0.09 and -0.33 ± 0.09, P = 0.010), delayed TTPn (9.04 ± 1.39 s versus 3.66 ± 0.79 s and 4.88 ± 1.10 s, P = 0.0064), shortened Tpr (22.75 ± 2.30 s versus 36.85 ± 2.68 s and 33 ± 2.49 s, P = 0.0010), and decreased Ppr (0.62 ± 0.08 versus 0.99 ± 0.15 and 0.97 ± 0.11, P = 0.0149) when subjected to median nerve electrical stimulation in the symptomatic side. After surgery, the patients with paresthesia showed shorter Tnr (1.53 ± 1.66 s versus 17.88 ± 22.61 s, P = 0.0002), increased Pnr (-0.14 ± 0.17 versus -0.44 ± 0.53, P = 0.0178), advanced TTPn (1.29 ± 1.21 s versus 7.29 ± 8.21 s, P = 0.0005), extended Tpr (36.94 ± 6.41 s versus 25.18 ± 15.51 s, P = 0.0091), increased Ppr (1.21 ± 0.87 versus 0.77 ± 0.60, P = 0.0201), and advanced TTPp (11.18 ± 4.70 s versus 27.29 ± 20.00 s, P = 0.0046). Bold-fMRI is

  15. Effects of ozone on sciatic nerve in rat.

    PubMed

    Lin, Q; Chen, H; Lu, C; Wang, B; Zhang, Y; He, X; Yu, B

    2011-09-01

    This study evaluated the influence of ozone on rat sciatic nerve structure and function. Thirty Wistar rats were randomly divided into six groups (n = 5). In groups I to IV, 1ml of ozone (O(3)) 10 μg/ml, 30 μg/ml, 50 μg/ml, 8 0 μg/ml was injected at the junction of gluteus maximus margin and lateral edge of the long head of biceps femoris respectively, in group V, 1 ml of pure O(2) was injected at the same point, and group V had puncture without any injection. Ozone was manufactured by an ozone generator (Ozone Line Co, Italy). The rats were investigated by both gross measurement and behavioral changes. One day, one week and three weeks after injection, rat hindlimb footprints were measured and the sciatic nerve function index (SFI) was calculated, and after three weeks, all right sciatic nerves were exposed under anesthesia. Near neural stimulation of the rat sciatic nerve was calculated and nerve conduction velocity, latency and maximum amplitude recorded. Animals were sacrificed for pathology, and ipsilateral triceps surae were taken for wet weight. No serious behavioral abnormalities were observed in any animal. SFI comparison in the various times and various groups showed no significant differences (p<0.05), and nerve conduction velocity, latency and maximum amplitude difference amongst the groups was not significant (p<0.05). There were no abnormalities in peripheral nerves pathologically after injection. Our initial study suggests that ozone concentrations from 10 μg/ml to 80 μg/ml injected around rat's peripheral nerve will not cause serious sequelae or serious damage to the structure and function of peripheral nerve. This finding provides evidence of the safety of ozone injected around the peripheral nerve.

  16. Effects of Median Nerve Neural Mobilization in Treating Cervicobrachial Pain: A Randomized Waiting List-controlled Clinical Trial.

    PubMed

    Rodríguez-Sanz, David; López-López, Daniel; Unda-Solano, Francisco; Romero-Morales, Carlos; Sanz-Corbalán, Irene; Beltrán-Alacreu, Hector; Calvo-Lobo, César

    2017-07-22

    There is a current lack of sufficiently high-quality randomized controlled clinical trials that measure the effectiveness of neural tissue mobilization techniques such as median nerve neural mobilization (MNNM) and their specific effects on cervicobrachial pain (CP). This study aim was to compare the effectiveness of MNNM in subjects with CP versus a waiting list control group (WLCG). A single-blinded, parallel, randomized controlled clinical trial was performed (NCT02596815). Subjects were recruited with a medical diagnosis of CP corroborated by magnetic resonance imaging. In total, 156 individuals were screened, 60 subjects were recruited, and 51 completed the trial. Pain intensity reported using the Numeric Rating Scale for Pain (NRSP; primary outcome), cervical range of motion (CROM) and functionality using the Quick-DASH scale were the outcome measurements. Assessments were conducted at baseline and 1-hour after treatment (1, 15 and 30 intervention days). Therefore, MNNM was implemented with 30-days of follow-up. The NRSP values of the MNNM group were significantly (p<0.0001; 95% CI) superior to those obtained in the WLCG. Subjects treated with MNNM reported an NRSP decrease of 3.08 points at discharge. CROM and Quick-DASH outcome values were significantly (p˂0.0001; 95%CI) improved only in the MNNM group. Hedges' g showed a very large effect of the MNNM intervention. MNNM may be superior to no treatment in reducing pain and increasing function in the affected upper limb of subjects with CP. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  17. Detection of catecholamine and luteinizing hormone-releasing hormone (LH-RH) containing nerve endings in the median eminence and the organon vasculosum laminae terminalis by fluorescence histochemistry and immunohistochemistry on the same microscopic sections.

    PubMed

    Ibata, Y; Watanabe, K; Kinoshita, H; Kubo, S; Sano, Y; Sin, S; Hashimura, E; Imagawa, K

    1979-02-01

    Distribution of catecholamine (CA) and LH-RH nerve endings in the median eminence (ME) and the organon vasculosum laminae terminalis (OVLT) of the rat was investigated by application of fluorescence histochemistry and immunohistochemistry on the same sections of the tissue. In the ME, those two kinds of endings coexisted in the lateral portion of the middle part of ME, and in the wall of tuberoinfundibular sulcus, where they might be considered to have functional correlation. In the OVLT they were also distributed in fairly near distance, but they were not so closely associated as observed in the ME.

  18. Median preoptic nucleus and subfornical organ drive renal sympathetic nerve activity via a glutamatergic mechanism within the paraventricular nucleus.

    PubMed

    Llewellyn, Tamra; Zheng, Hong; Liu, Xuefei; Xu, Bo; Patel, Kaushik P

    2012-02-15

    The paraventricular nucleus (PVN) of the hypothalamus is involved in the neural control of sympathetic drive, but the precise mechanism(s) that influences the PVN is not known. The activation of the PVN may be influenced by input from higher forebrain areas, such as the median preoptic nucleus (MnPO) and the subfornical organ (SFO). We hypothesized that activation of the MnPO or SFO would drive the PVN through a glutamatergic pathway. Neuroanatomical connections were confirmed by the recovery of a retrograde tracer in the MnPO and SFO that was injected bilaterally into the PVN in rats. Microinjection of 200 pmol of N-methyl-d-aspartate (NMDA) or bicuculline-induced activation of the MnPO and increased renal sympathetic activity (RSNA), mean arterial pressure, and heart rate in anesthetized rats. These responses were attenuated by prior microinjection of a glutamate receptor blocker AP5 (4 nmol) into the PVN (NMDA - ΔRSNA 72 ± 8% vs. 5 ± 1%; P < 0.05). Using single-unit extracellular recording, we examined the effect of NMDA microinjection (200 pmol) into the MnPO on the firing activity of PVN neurons. Of the 11 active neurons in the PVN, 6 neurons were excited by 95 ± 17% (P < 0.05), 1 was inhibited by 57%, and 4 did not respond. The increased RSNA after activation of the SFO by ANG II (1 nmol) or bicuculline (200 pmol) was also reduced by AP5 in the PVN (for ANG II - ΔRSNA 46 ± 7% vs. 17 ± 4%; P < 0.05). Prior microinjection of ANG II type 1 receptor blocker losartan (4 nmol) into the PVN did not change the response to ANG II or bicuculline microinjection into the SFO. The results from this study demonstrate that the sympathoexcitation mediated by a glutamatergic mechanism in the PVN is partially driven by the activation of the MnPO or SFO.

  19. Estimation and pharmacodynamic consequences of the minimum effective anesthetic volumes for median and ulnar nerve blocks: a randomized, double-blind, controlled comparison between ultrasound and nerve stimulation guidance.

    PubMed

    Ponrouch, Matthieu; Bouic, Nicolas; Bringuier, Sophie; Biboulet, Philippe; Choquet, Olivier; Kassim, Michèle; Bernard, Nathalie; Capdevila, Xavier

    2010-10-01

    Nerve stimulation and ultrasound guidance are the most popular techniques for peripheral nerve blocks. However, the minimum effective anesthetic volume (MEAV) in selected nerves for both techniques and the consequences of decreasing the local anesthetic volume on the pharmacodynamic characteristics of nerve block remain unstudied. We designed a randomized, double-blind controlled comparison between neurostimulation and ultrasound guidance to estimate the MEAV of 1.5% mepivacaine and pharmacodynamics in median and ulnar nerve blocks. Patients scheduled for carpal tunnel release were randomized to ultrasound guidance (UG) or neurostimulation (NS) groups. A step-up/step-down study model (Dixon method) was used to determine the MEAV with nonprobability sequential dosing based on the outcome of the previous patient. The starting dose of 1.5% mepivacaine was 13 and 11 mL for median and ulnar nerves at the humeral canal. Block success/failure resulted in a decrease/increase of 2 mL. A blinded physician assessed sensory blockade at 2-minute intervals for 20 minutes. Block onset time and duration were noted. The MEAV50 (SD) of the median nerve was lower in the UG group 2 (0.1) mL (95% confidence interval [CI] = [1, 96] to [2, 04]) than in the NS group 4 (3.8) mL (95% CI = [2, 4] to [5, 6]) (P = 0.017). There was no difference for the ulnar nerve between UG group 2 (0.1) mL (95% CI = [1, 96] to [2, 04]) and NS group 2.4 (0.6) mL (95% CI = [2, 1] to [2, 7]). The duration of sensory blockade was significantly correlated to local anesthetic volume, but onset time was not modified. Ultrasound guidance selectively provided a 50% reduction in the MEAV of mepivacaine 1.5% for median nerve sensory blockade in comparison with neurostimulation. Decreasing the local anesthetic volume can decrease sensory block duration but not onset time.

  20. Effects of swimming exercise on nerve regeneration in a rat sciatic nerve transection model

    PubMed Central

    Liao, Chien-Fu; Yang, Tse-Yen; Chen, Yung-Hsiang; Yao, Chun-Hsu; Way, Tzong-Der; Chen, Yueh-Sheng

    2017-01-01

    Background: Swimming is commonly considered to be an efficient rehabilitation exercise to treat peripheral nerve injury. However, the most effective resistance level and exercise duration is still unclear. We investigated the effects and mechanisms of swimming at various exertion levels in a rat sciatic nerve transection model. Methods: Sciatic nerve transection rats were randomized into the following four groups based on swimming duration (from the 7th day to the 28th day post-surgery): sedentary control group (SC), S10 group (10 min/3 times/week), S20 group (20 min/3 times/week), and S30 group (30 min/3 times/week) (n = 10 each). Axon regeneration, electrophysiological properties, muscular weights, macrophage infiltration, and nerve repair associated maker, calcitonin gene-related peptide (CGRP), were measured. Results: Dramatic higher successful percentages of nerve regeneration across the 10-mm gaps in swimming groups compared to the SC group. Total area of nerve regeneration significantly improved in the S10 group; however, electrophysiological properties, muscular weights, and macrophage infiltration in the regenerated nerves of rats did not differ significantly between the various exercise groups. CGRP expression was significantly increased in the spinal cord of rats in the S20 group. Conclusions: Our data indicated that CGRP-related axonal regeneration improved significantly with moderate swimming. These results should inspire new studies in physiotherapeutic practice for related human treatment. PMID:28474579

  1. The prevalence of accessory heads of the flexor pollicis longus and the flexor digitorum profundus muscles in Egyptians and their relations to median and anterior interosseous nerves.

    PubMed

    El Domiaty, M A; Zoair, M M; Sheta, A A

    2008-02-01

    Entrapment neuropathy in the forearm is not uncommon. Surgical interference for nerve decompression should be preceded by accurate diagnosis of the exact cause and site of the nerve entrapment. The aim of the present study was to investigate the prevalence of accessory heads of the flexor pollicis longus and flexor digitorum profundus muscles (FPLah) and (FDPah) in Egyptians and their topographical relationship with both the median nerve and its anterior interosseous branch. A total of 42 upper limbs of embalmed cadavers, 36 from males and 6 from females, were examined to elucidate the prevalence of both the FPLah and the FDPah muscles, their origin, insertion, nerve supply and morphology. The distribution of these two muscles in the right and left male and female upper limbs and their relationship to the anterior interosseous and median nerves were recorded. The total lengths of both accessory muscles and the lengths of their fleshy bellies and tendons were also measured. The FPLah was found to be present more frequently (61.9%) than it was absent, whereas the FDPah was observed in only 14.24% of the specimens examined. The combination of the accessory muscles in the same forearm was noticed in 9.52% of cases. As regards side, the FPLah appeared in 77.7% of the right forearms and in 50% of the left, while the FDPah was found in only 25% of the left forearms. The accessory muscles showed no single morphology, as the FPLah appeared fusiform in 53.8%, slender in 30.8% and voluminous fusiform in 15.4%, while the FDPah was slender in 66.6% and triangular in 33.3% of specimens. The FPLah arose mainly from the under surface of flexor digitorum superficialis, while the FDPah took its origin from the under surface of flexor digitorum superficialis or from the medial epicondyle. The insertion of the FPLah was mainly into the upper third of the FPL tendon, while the FDPah tendon joined the tendons of the flexor digitorum profundus muscle to the index or middle and ring

  2. Mesenchymal Stem Cells Enhance Nerve Regeneration in a Rat Sciatic Nerve Repair and Hindlimb Transplant Model

    PubMed Central

    Cooney, Damon S.; Wimmers, Eric G.; Ibrahim, Zuhaib; Grahammer, Johanna; Christensen, Joani M.; Brat, Gabriel A.; Wu, Lehao W.; Sarhane, Karim A.; Lopez, Joseph; Wallner, Christoph; Furtmüller, Georg J.; Yuan, Nance; Pang, John; Sarkar, Kakali; Lee, W. P. Andrew; Brandacher, Gerald

    2016-01-01

    This study investigates the efficacy of local and intravenous mesenchymal stem cell (MSC) administration to augment neuroregeneration in both a sciatic nerve cut-and-repair and rat hindlimb transplant model. Bone marrow-derived MSCs were harvested and purified from Brown-Norway (BN) rats. Sciatic nerve transections and repairs were performed in three groups of Lewis (LEW) rats: negative controls (n = 4), local MSCs (epineural) injection (n = 4), and systemic MSCs (intravenous) injection (n = 4). Syngeneic (LEW-LEW) (n = 4) and allogeneic (BN-LEW) (n = 4) hindlimb transplants were performed and assessed for neuroregeneration after local or systemic MSC treatment. Rats undergoing sciatic nerve cut-and-repair and treated with either local or systemic injection of MSCs had significant improvement in the speed of recovery of compound muscle action potential amplitudes and axon counts when compared with negative controls. Similarly, rats undergoing allogeneic hindlimb transplants treated with local injection of MSCs exhibited significantly increased axon counts. Similarly, systemic MSC treatment resulted in improved nerve regeneration following allogeneic hindlimb transplants. Systemic administration had a more pronounced effect on electromotor recovery while local injection was more effective at increasing fiber counts, suggesting different targets of action. Local and systemic MSC injections significantly improve the pace and degree of nerve regeneration after nerve injury and hindlimb transplantation. PMID:27510321

  3. Severe, traumatic soft-tissue loss in the antecubital fossa and proximal forearm associated with radial and/or median nerve palsy: nerve recovery after coverage with a pedicled latissimus dorsi muscle flap.

    PubMed

    Al-Qattan, M M

    2001-02-01

    A total of 6 patients with complex, traumatic wounds of the antecubital fossa and proximal forearm were included in this study. All patients presented with radial and/or median nerve palsies in addition to their soft-tissue defect. Except for 1 patient with a 15-cm defect of the radial nerve, all other traumatized nerves appeared in-continuity at the time of surgery. However, the nerve injury was severe enough to induce Wallerian degeneration (i.e., axonotmesis in traumatized nerves in-continuity). Three patients required brachial artery reconstruction with a reverse saphenous vein graft. Wound coverage was accomplished using a pedicled latissimus dorsi muscle flap, which was covered with a split-thickness skin graft. Successful reconstruction was obtained in all patients. Follow-up ranged from 2 to 6 years. The range of motion at the elbow and forearm was considered excellent in 5 patients and good in the remaining patient who had an intra-articular fracture. Motor recovery of traumatized nerves in-continuity was observed in all but 1 patient who had persistent partial anterior interosseous nerve palsy. The grip strength of the injured hand measured 70% to 85% of the contralateral uninjured hand. Median nerve sensory recovery was excellent in all patients. The versatility of the pedicled latissimus dorsi muscle flap for coverage of these complex wounds with traumatized neurovascular bundles around the elbow is discussed.

  4. Regeneration of facial nerve defects with xenogeneic acellular nerve grafts in a rat model.

    PubMed

    Zhu, Guochen; Lou, Weihua

    2014-04-01

    Because of ease of harvest and low immunogenicity, xenogeneic acellular nerve graft (XANG) may be an alternative to autologous nerve to repair facial nerve defects. Facial nerve defects of Wistar rats were repaired by XANG, and nerve gap regeneration was investigated by electrophysiological test, horseradish peroxidase (HRP) retrograde tracing and histomorphometric analysis, as compared to autograft. Twenty weeks after the grafting, electrophysiology showed that whisker pad muscles responded to the electrical stimuli given at the site proximal to the transplantation in 2 groups. Some HRP-labeled facial motorneurons were located on the facial nucleus of the operated side, and an abundance of myelinated axons were found at the middle of the grafts and obvious motor endplates in the target muscles in 2 groups, although they were inferior to the contralateral side in numbers. XANG represents an alternative approach for the reconstruction of peripheral facial nerve defects. Copyright © 2013 Wiley Periodicals, Inc.

  5. Effects of ciguatoxin on nerve excitability in rats (Part I).

    PubMed

    Cameron, J; Flowers, A E; Capra, M F

    1991-01-01

    Ciguatera poisoning is the most common fish food poisoning encountered in man. Electrophysiological studies were performed on the ventral nerve of the tail on adult rats following intraperitoneal injection of toxic fish extract. Significant slowing of both mixed and motor nerve conduction velocities and F wave responses were recorded. Motor and mixed nerve amplitudes were significantly reduced. Both absolute and supernormal periods were significantly prolonged together with an exaggeration of the supernormal response. These findings indirectly suggest that ciguatoxin acts on mammalian nerve by prolonging sodium channel activation.

  6. Motor cortex neuroplasticity associated with lingual nerve injury in rats.

    PubMed

    Adachi, Kazunori; Lee, Jye-Chang; Hu, James W; Yao, Dongyuan; Sessle, Barry J

    2007-09-01

    The aim of this study was to determine if lingual nerve trauma affects the features of face primary motor cortex (MI) defined by intracortical microstimulation (ICMS). The left lingual nerve was transected in adult male rats by an oral surgical procedure; sham rats (oral surgery but no nerve transection) as well as naive intact rats served as control groups. ICMS was applied at post-operative days 0, 7, 14, 21, and 28 to map the jaw and tongue motor representations in face MI by analyzing ICMS-evoked movements and electromyographic activity recorded in the genioglossus (GG) and anterior digastric (AD) muscles. There were no statistically significant effects of acute (day 0) nerve transection or sham procedure (p > 0.05). The surgery in the sham animals was associated with limited post-operative change; this was reflected in a significant (p < 0.05) increase in the number of GG sites in left MI at post-operative day 14 compared to day 0. However, nerve transection was associated with significant increases in the total number of AD and GG sites in left or right MI or specifically the number of GG sites in rats at post-operative days 21 or 28 compared to earlier time periods. There were also significant differences between nerve-transected and sham groups at post-operative days 7, 14, or 21. These findings suggest that lingual nerve transection is associated with significant time-dependent neuroplastic changes in the tongue motor representations in face MI.

  7. Localization of cervical and cervicomedullary stimulation leads for pain treatment using median nerve somatosensory evoked potential collision testing.

    PubMed

    Balzer, Jeffrey R; Tomycz, Nestor D; Crammond, Donald J; Habeych, Miguel; Thirumala, Parthasarathy D; Urgo, Louisa; Moossy, John J

    2011-01-01

    Spinal cord stimulation (SCS) is being currently used to treat medically refractory pain syndromes involving the face, trunk, and extremities. Unlike thoracic SCS surgery, during which patients can be awakened from conscious sedation to confirm good lead placement, safe placement of paddle leads in the cervical spine has required general anesthesia. Using intraoperative neurophysiological monitoring, which is routinely performed during these cases at the authors' institution, the authors developed an electrophysiological technique to intraoperatively lateralize lead placement in the cervical epidural space. Data from 44 patients undergoing median and tibial nerve somatosensory evoked potential (SSEP) monitoring during cervical laminectomy or hemilaminectomy for placement or replacement of dorsal column stimulators were retrospectively reviewed. Paddle leads were positioned laterally or just off midline and parallel to the axis of the cervical spinal cord to effectively treat what was most commonly a predominant unilateral pain syndrome. During SSEP recording, the spinal cord stimulator was activated at 1.0 V and increased in increments of 1.0 V to a maximum of 6.0 V. A unilateral reduction or abolishment of SSEP amplitude was regarded as an indicator of lateralized placement of the stimulator. A bilateral diminutive effect on SSEPs was interpreted as a midline or near midline lead placement. Epidural stimulation abolished or significantly reduced SSEP amplitudes in all patients undergoing placement for a unilateral pain syndrome. In 15 patients, electrodes were repositioned intraoperatively to achieve the most robust SSEP amplitude reduction or abolishment using the lowest epidural stimulation intensity. In all cases in which a significant unilateral reduction in SSEP was observed, the patient reported postoperative sensory alterations in target locations predicted by intraoperative SSEP changes. Placement of cervical spinal cord stimulators for bilateral pain

  8. Sonography assessment of the median nerve during cervical lateral glide and lateral flexion. Is there a difference in neurodynamics of asymptomatic people?

    PubMed

    Brochwicz, Peter; von Piekartz, Harry; Zalpour, Christoff

    2013-06-01

    There is clinical evidence that cervical lateral glide (CLG) improves neurodynamics and alleviates pain in patients who suffer from neurogenic arm pain. Cervical lateral flexion (CLF) is also a treatment method and a means of testing neurodynamics. However, for both techniques nerve movement has not yet been investigated using ultrasound imaging (US). The purpose of this study was to quantify median nerve movement in the arm during CLG and CLF. For this study 27 healthy participants were recruited. Longitudinal movement of the median nerve was measured using US during CLG and CLF with the shoulder in 30° abduction in the middle and distal forearm (Fad). Data could be obtained from 11 participants (6 women and 5 men, average age 25.6 years, ± 2.25) at the middle forearm (Fam) and from 9 participants (5 women and 4 men, average age 27.2 years, ± 2.75) at the Fad. When applying CLF, the median nerve moved 2.3 mm (SEM ± 0.1 mm) at the Fam. At the same measuring point the median nerve moved 3.3 mm (SEM ± 0.3 mm, p = 0.005) by applying CLG. At the Fad the difference between CLF and CLF amounted to 0.6 mm (CLF: 1.9 mm (SEM ± 0.2 mm, CLG: 2.5 mm (SEM ± 0.2 mm, p ≤ 0.05). The movements during CLG are larger than during CLF. This difference is statistically significant. However, the statistical relevance cannot be extrapolated to a clinical relevance.

  9. Median preoptic nucleus and subfornical organ drive renal sympathetic nerve activity via a glutamatergic mechanism within the paraventricular nucleus

    PubMed Central

    Llewellyn, Tamra; Zheng, Hong; Liu, Xuefei; Xu, Bo

    2012-01-01

    The paraventricular nucleus (PVN) of the hypothalamus is involved in the neural control of sympathetic drive, but the precise mechanism(s) that influences the PVN is not known. The activation of the PVN may be influenced by input from higher forebrain areas, such as the median preoptic nucleus (MnPO) and the subfornical organ (SFO). We hypothesized that activation of the MnPO or SFO would drive the PVN through a glutamatergic pathway. Neuroanatomical connections were confirmed by the recovery of a retrograde tracer in the MnPO and SFO that was injected bilaterally into the PVN in rats. Microinjection of 200 pmol of N-methyl-d-aspartate (NMDA) or bicuculline-induced activation of the MnPO and increased renal sympathetic activity (RSNA), mean arterial pressure, and heart rate in anesthetized rats. These responses were attenuated by prior microinjection of a glutamate receptor blocker AP5 (4 nmol) into the PVN (NMDA − ΔRSNA 72 ± 8% vs. 5 ± 1%; P < 0.05). Using single-unit extracellular recording, we examined the effect of NMDA microinjection (200 pmol) into the MnPO on the firing activity of PVN neurons. Of the 11 active neurons in the PVN, 6 neurons were excited by 95 ± 17% (P < 0.05), 1 was inhibited by 57%, and 4 did not respond. The increased RSNA after activation of the SFO by ANG II (1 nmol) or bicuculline (200 pmol) was also reduced by AP5 in the PVN (for ANG II − ΔRSNA 46 ± 7% vs. 17 ± 4%; P < 0.05). Prior microinjection of ANG II type 1 receptor blocker losartan (4 nmol) into the PVN did not change the response to ANG II or bicuculline microinjection into the SFO. The results from this study demonstrate that the sympathoexcitation mediated by a glutamatergic mechanism in the PVN is partially driven by the activation of the MnPO or SFO. PMID:22160544

  10. Characterization of melatonin binding sites in the Harderian gland and median eminence of the rat

    SciTech Connect

    Lopez-Gonzalez, M.A.; Calvo, J.R.; Rubio, A.; Goberna, R.; Guerrero, J.M. )

    1991-01-01

    The characterization of specific melatonin binding sites in the Harderian gland (HG) and median eminence (ME) of the rat was studied using ({sup 125}I)melatonin. Binding of melatonin to membrane crude preparations of both tissues was dependent on time and temperature. Thus, maximal binding was obtained at 37{degree}C after 30-60 min incubation. Binding was also dependent on protein concentration. The specific binding of ({sup 125}I)melatonin was saturable, exhibiting only the class of binding sites in both tissues. The dissociation constants (Kd) were 170 and 190 pM for ME and HG, respectively. The concentration of the binding sites in ME was 8 fmol/mg protein, and in the HG 4 fmol/mg protein. In competition studies, binding of ({sup 125}I)melatonin to ME or HG was inhibited by increasing concentration of native melatonin; 50% inhibition was observed at about 702 and 422 nM for ME and HG, respectively. Additionally, the ({sup 125}I)melatonin binding to the crude membranes was not affected by the addition of different drugs such as norepinephrine, isoproterenol, phenylephrine, propranolol, or prazosin. The results confirm the presence of melatonin binding sites in median eminence and show, for the first time, the existence of melatonin binding sites in the Harderian gland.

  11. Communications between the palmar digital branches of the median and ulnar nerves: A study in human fetuses and a review of the literature.

    PubMed

    Unver Dogan, Nadire; Uysal, Ismihan Ilknur; Karabulut, Ahmet Kagan; Seker, Muzaffer; Ziylan, Taner

    2010-03-01

    In this study, median nerves (MNs) and ulnar nerves (UNs) were dissected in 200 palmar sides of hands (left and right) of 100 (50 male, 50 female) spontaneously aborted fetuses with no detectable malformations. The fetuses, whose gestational ages ranged from 13 to 40 weeks, were dissected under an operating microscope. The MN divided first into a lateral ramus and a medial ramus and then formed a common digital nerve. The first common digital nerve trifurcated in all of the studied cases. The branching patterns were classified into two types (Type 1 and Type 2) based on the relationship with the flexor retinaculum (behind/distal of it). A communication branch between the UNs and MNs in the palmar surface of the hand was found in 59 hands (29.5%). The proper palmar digital nerves were numbered from p1 to p10, starting from the radial half of the thumb to the ulnar half of the little finger, and these nerves exhibited six types of variations. The present data obtained from human fetuses will aid in elucidating the developmental anatomy of the nervous system and provide hand surgeons with a more complete anatomical picture to help them to avoid iatrogenic injuries.

  12. Intrinsic properties of the sodium sensor neurons in the rat median preoptic nucleus

    PubMed Central

    Voisin, Aurore N.; Mouginot, Didier

    2012-01-01

    The essential role of the median preoptic nucleus (MnPO) in the integration of chemosensory information associated with the hydromineral state of the rat relies on the presence of a unique population of sodium (Na+) sensor neurons. Little is known about the intrinsic properties of these neurons; therefore, we used whole cell recordings in acute brain slices to determine the electrical fingerprints of this specific neural population of rat MnPO. The data collected from a large sample of neurons (115) indicated that the Na+ sensor neurons represent a majority of the MnPO neurons in situ (83%). These neurons displayed great diversity in both firing patterns induced by transient depolarizing current steps and rectifying properties activated by hyperpolarizing current steps. This diversity of electrical properties was also present in non-Na+ sensor neurons. Subpopulations of Na+ sensor neurons could be distinguished, however, from the non-Na+ sensor neurons. The firing frequency was higher in Na+ sensor neurons, showing irregular spike discharges, and the amplitude of the time-dependent rectification was weaker in the Na+ sensor neurons than in non-Na+ sensor neurons. The diversity among the electrical properties of the MnPO neurons contrasts with the relative function homogeneity (Na+ sensing). However, this diversity might be correlated with a variety of direct synaptic connections linking the MnPO to different brain areas involved in various aspects of the restoration and conservation of the body fluid homeostasis. PMID:22874426

  13. [Simplified sciatic nerve approach by the posterior route at the median gluteus-femoral sulcus region, with a neurostimulator.].

    PubMed

    Fonseca, Neuber Martins; Ferreira, Fernando Xavier; Ruzi, Roberto Araújo; Pereira, Gulherme Carnaval Souza

    2002-11-01

    The sciatic nerve may be blocked by several routes, all of them with advantages and disadvantages. It is the largest human nerve in diameter and length, being the prolongation of the upper sacral plexus fascicle (L4, L5, S2 and S3). It leaves the pelvis through the foramen ischiadicum majus, passing below the piriform muscle and going down between the greater trochanter and the ischial tuberosity, continuing along the femoral dorsum, anterior to biceps femoris and semitendinous muscles, to the lower femoral third, where it is divided in two major branches called tibial and common fibular nerves. It becomes superficial at the lower border of the gluteus maximus muscle. Based on this anatomic description, we developed a posterior approach with the following advantages: easy identification of the surface anatomy, superficial level of the nerve at this location; and less discomfort to patients since a 5 cm needle may be used. Seventeen ASA I - III patients aged 21 to 79 years, weighing 55 to 90 kg, undergoing leg or foot surgery were studied. After monitoring, patients were placed in the prone position and blockade was performed at the middle point of the sulcus gluteus (skin fold between nates and posterior thigh), with the aid of a neurostimulator, using 1% plain lidocaine (300 mg). Onset time, blockade performing time, and tibial, common fibular and cutaneous femoris posterior nerves anesthesia were evaluated. Saphenous nerve was also blocked with 5 ml of 1% lidocaine whenever needed. Adequate anesthesia was obtained in all cases. There was no patient with cutaneous femoris posterior nerve anesthesia. Blockade performing time was 8.58 +/- 5.71 min. Onset time was 5.88 +/- 1.6 min. Sensory and motor block duration was 4.05 +/- 1.1 and 2.9 +/- 0.8 hours, respectively. This new approach is effective and easy. However, it is not indicated when the cutaneous femoris posterior nerve anesthesia is necessary.

  14. Activation of Neurokinin 3 Receptors in the Median Preoptic Nucleus Decreases Core Temperature in the Rat

    PubMed Central

    Dacks, Penny A.; Krajewski, Sally J.

    2011-01-01

    Estrogens have pronounced effects on thermoregulation, as illustrated by the occurrence of hot flushes secondary to estrogen withdrawal in menopausal women. Because neurokinin B (NKB) gene expression is markedly increased in the infundibular (arcuate) nucleus of postmenopausal women, and is modulated by estrogen withdrawal and replacement in multiple species, we have hypothesized that NKB neurons could play a role in the generation of flushes. There is no information, however, on whether the primary NKB receptor [neurokinin 3 receptor (NK3R)] modulates body temperature in any species. Here, we determine the effects of microinfusion of a selective NK3R agonist (senktide) into the rat median preoptic nucleus (MnPO), an important site in the heat-defense pathway. Senktide microinfusion into the rat MnPO decreased core temperature in a dose-dependent manner. The hypothermia induced by senktide was similar in ovariectomized rats with and without 17β-estradiol replacement. The hypothermic effect of senktide was prolonged in rats exposed to an ambient temperature of 29.0 C, compared with 21.5 C. Senktide microinfusion also altered tail skin vasomotion in rats exposed to an ambient temperature of 29.0 but not 21.5 C. Comparisons of the effects of senktide at different ambient temperatures indicated that the hypothermia was not secondary to thermoregulatory failure or a reduction in cold-induced thermogenesis. Other than a very mild increase in drinking, senktide microinfusion did not affect behavior. Terminal fluorescent dextran microinfusion showed targeting of the MnPO and adjacent septum, and immunohistochemical studies revealed that senktide induced a marked increase in Fos-activation in the MnPO. Because MnPO neurons expressed NK3R-immunoreactivity, the induction of MnPO Fos by senktide is likely a direct effect. By demonstrating that NK3R activation in the MnPO modulates body temperature, these studies support the hypothesis that hypothalamic NKB neurons could be

  15. Acute and Subchronic Toxicity Study of the Median Septum of Juglans regia in Wistar Rats

    PubMed Central

    Ravanbakhsh, Asma; Mahdavi, Majid; Jalilzade-Amin, Ghader; Javadi, Shahram; Maham, Masoud; Mohammadnejad, Daryosh; Rashidi, Mohammad Reza

    2016-01-01

    Purpose: Median septum of Juglans regia L. (Juglandaceae) with anti-diabetic effects has been used in Iranian traditional medicine. The present study estimates both oral acute and subchronic toxicities. Methods: In the oral acute toxicity study, female Wistar rats were treated with doses of 10, 100, 1000, 1600, 2900 and 5000 mg/ kg of the Juglans regia septum of methanol extract (JRSME), and were monitored for 14 days. In subchronic study, JRSME was administered by gavage at dose of 1000 mg/kg daily in Wistar rats for 28 days. Antioxidant status and biochemical examinations were fulfilled, and the vital organs were subjected to pathological analyses. Results: The extract did not produce any toxic signs or deaths; the medium lethal dose must be higher than 5000 mg/kg. In subchronic study, No significant morphological and histopathological changes were observed in the studied tissues. There was a significant increase in serum malondialdehyde (MDA) level in treated group compared to control after 4 weeks of JRSME intake. The treatment of rats resulted in a significant reduction of serum urea level (p<0.05), kidney’s xanthine dehydrogenase (XDH) activity (p<0.001) and elevation of aldehyde oxidase (AO) activity (p<0.05) in kidney. In the treated group, the mean diameter of glomerulus and proximal urine tube epithelium stature was slightly greater than control group. A significant increase in serum MDA level is subject for further studies. Conclusion: This study showed that the extract has no acute or subacute adverse effects with dose of 1000 mg/kg. The administration of JRSME may improve kidney structure and function and help in treatment of some chronic diseases. PMID:28101461

  16. Sciatic nerve regeneration in rats subjected to ketogenic diet.

    PubMed

    Liśkiewicz, Arkadiusz; Właszczuk, Adam; Gendosz, Daria; Larysz-Brysz, Magdalena; Kapustka, Bartosz; Łączyński, Mariusz; Lewin-Kowalik, Joanna; Jędrzejowska-Szypułka, Halina

    2016-01-01

    Ketogenic diet (KD) is a high-fat-content diet with insufficiency of carbohydrates that induces ketogenesis. Besides its anticonvulsant properties, many studies have shown its neuroprotective effect in central nervous system, but its influence on peripheral nervous system has not been studied yet. We examined the influence of KD on regeneration of peripheral nerves in adult rats. Fifty one rats were divided into three experimental (n = 15) and one control (n = 6) groups. Right sciatic nerve was crushed and animals were kept on standard (ST group) or ketogenic diet, the latter was introduced 3 weeks before (KDB group) or on the day of surgery (KDA group). Functional (CatWalk) tests were performed once a week, and morphometric (fiber density, axon diameter, and myelin thickness) analysis of the nerves was made after 6 weeks. Body weight and blood ketone bodies level were estimated at the beginning and the end of experiment. Functional analysis showed no differences between groups. Morphometric evaluation showed most similarities to the healthy (uncrushed) nerves in KDB group. Nerves in ST group differed mostly from all other groups. Ketone bodies were elevated in both KD groups, while post-surgery animals' body weight was lower as compared to ST group. Regeneration of sciatic nerves was improved in KD - preconditioned rats. These results suggest a neuroprotective effect of KD on peripheral nerves.

  17. Differential recruitment of high frequency wavelets (600 Hz) and primary cortical response (N20) in human median nerve somatosensory evoked potentials.

    PubMed

    Klostermann, F; Nolte, G; Losch, F; Curio, G

    1998-11-06

    Human median nerve somatosensory evoked potentials contain a burst of high-frequency (600 Hz) wavelets superimposed on the primary cortical response (N20). These presumably reflect highly-synchronized repetitive thalamic and/or intracortical population spike bursts and are diminished in non-REM sleep with N20 persisting. Here the burst/N20 relation in awake subjects was examined by using eight different intensities of electric median nerve stimuli. In all subjects the amplitude recruitment of both N20 and burst could be modeled adequately as a sigmoidal function of stimulus intensity. While 8/10 subjects showed a parallel recruitment, 2/10 subjects required significantly higher stimulation intensities for burst than for N20 recruitment. This dampened burst recruitment possibly reflects slight vigilance fluctuations in open-eyed awake subjects; a further increase of burst thresholds could explain the burst attenuation when entering shallow sleep.

  18. [A case of transient postoperative median nerve palsy due to the use of the wrist holder to stabilize an intra-arterial catheter].

    PubMed

    Ohata, Hiroto; Iida, Yuko; Kito, Kazuhiro; Kawamura, Michika; Yamashita, Mika; Ohta, Shuichiro; Ueda, Norio; Iida, Hiroki

    2013-06-01

    We experienced a case of right median nerve palsy at the distal forearm following abdominal surgery. We postulate that the cause of the median nerve palsy is overextension of the wrist by the inappropriate fixation with a holder. The patient was a 46-year-old man with habit of smoking receiving low-anterior resection of the rectum under general and epidural anesthesia in lithotomy position. During surgery his upper limbs were placed on padded arm board abducted about 80 degrees and affixed with soft cotton. His forearms were slightly supinated, whereas his elbows were not over-extended. A 22 G cannula was inserted in the right radial artery and the right wrist was fixed with plastic-holder with soft pad. This position was maintained throughout the operation approximetly for 250 minutes. During anesthesia any special events regarding hemodynamic variables were not observed. He complained of numbness in the palmar side of the digits 1-3 on his right hand without motor disturbance 4 hours after the operation. Examination by the anesthesiologist revealed median nerve palsy. Fortunately, this symptom gradually but completely resolved over the next few days. The possible causes of this neuropathy include the overextension of the wrist or the unexpected extension of the elbow beyond the acceptable range by the supination of forearm, which was induced by the attachment used to stabilize an intra-arterial catheter. Therefore, in the current case we should have returned the wrists promptly to the neutral position following arterial catheter placement to prevent the median nerve palsy. This case suggests the importance of holding the proper position of the arm during surgery.

  19. A polylactic acid non-woven nerve conduit for facial nerve regeneration in rats.

    PubMed

    Matsumine, Hajime; Sasaki, Ryo; Yamato, Masayuki; Okano, Teruo; Sakurai, Hiroyuki

    2014-06-01

    This study developed a biodegradable nerve conduit with PLA non-woven fabric and evaluated its nerve regeneration-promoting effect. The buccal branch of the facial nerve of 8 week-old Lewis rats was exposed, and a 7 mm nerve defect was created. A nerve conduit made of either PLA non-woven fabric (mean fibre diameter 460 nm), or silicone tube filled with type I collagen gel, or an autologous nerve, was implanted into the nerve defect, and their nerve regenerative abilities were evaluated 13 weeks after the surgery. The number of myelinated neural fibres in the middle portion of the regenerated nerve was the highest for PLA tubes (mean ± SD, 5051 ± 2335), followed by autologous nerves (4233 ± 590) and silicone tubes (1604 ± 148). Axon diameter was significantly greater in the PLA tube group (5.17 ± 1.69 µm) than in the silicone tube group (4.25 ± 1.60 µm) and no significant difference was found between the PLA tube and autograft (5.53 ± 1.93 µm) groups. Myelin thickness was greatest for the autograft group (0.65 ± 0.24 µm), followed by the PLA tube (0.54 ± 0.18 µm) and silicone tube (0.38 ± 0.12 µm) groups, showing significant differences among the three groups. The PLA non-woven fabric tube, composed of randomly-connected PLA fibres, is porous and has a number of advantages, such as sufficient strength to maintain luminal structure. The tube has demonstrated a comparable ability to induce peripheral nerve regeneration following autologous nerve transplantation. Copyright © 2012 John Wiley & Sons, Ltd.

  20. Long-term outcome of the repair of 50 mm long median nerve defects in rhesus monkeys with marrow mesenchymal stem cells-containing, chitosan-based tissue engineered nerve grafts.

    PubMed

    Hu, Nan; Wu, Hong; Xue, Chengbin; Gong, Yanpei; Wu, Jian; Xiao, Zhaoqun; Yang, Yumin; Ding, Fei; Gu, Xiaosong

    2013-01-01

    Despite great progress in the fields of tissue engineering and stem cell therapy, the translational and preclinical studies are required to accelerate the clinical application of tissue engineered nerve grafts, as an alternative to autologous nerve grafts, for peripheral nerve repair. Rhesus monkeys (non-human primates) are more clinically relevant and more suitable for scaling up to humans as compared to other mammalians. Based on this premise, and considering a striking similarity in the anatomy and function between human and monkey hands, here we used chitosan/PLGA-based, autologous marrow mesenchymal stem cells (MSCs)-containing tissue engineered nerve grafts (TENGs) for bridging a 50-mm long median nerve defect in rhesus monkeys. At 12 months after grafting, locomotive activity observation, electrophysiological assessments, and FG retrograde tracing tests indicated that the recovery of nerve function by TENGs was more efficient than that by chitosan/PLGA scaffolds alone; histological and morphometric analyses of regenerated nerves further confirmed that the morphological reconstruction by TENGs was close to that by autografts and superior to that by chitosan/PLGA scaffolds alone. In addition, blood test and histopathological examination demonstrated that TENGs featured by addition of autologous MSCs could be safely used in the primate body. These findings suggest the efficacy of our developed TENGs for peripheral nerve regeneration and their promising perspective for clinical applications. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Induction of rat facial nerve regeneration by functional collagen scaffolds.

    PubMed

    Cao, Jiani; Xiao, Zhifeng; Jin, Wei; Chen, Bing; Meng, Danqing; Ding, Wenyong; Han, Sufang; Hou, Xiaoshan; Zhu, Tiansheng; Yuan, Baoyu; Wang, Jing; Liang, Weibang; Dai, Jianwu

    2013-01-01

    Nerve conduit provides a promising strategy for nerve regeneration, and the proper microenvironment in the lumen could improve the regeneration. Our previous work had demonstrated that linear ordered collagen scaffold (LOCS) could effectively guide the oriented growth of axons. Laminin is known as an important nerve growth promoting factor and can facilitate the growth cone formation. In addition, ciliary neurotrophic factor (CNTF) and brain-derived neurotrophic factor (BDNF) can effectively improve the nerve regeneration after nerve injuries. However, in practice, diffusion caused by the body fluids is the major obstacle in their applications. To retain CNTF or BDNF on the scaffolds, we produced collagen binding CNTF (CBD-CNTF), collagen binding BDNF (CBD-BDNF) and laminin binding CNTF (LBD-CNTF), laminin binding BDNF (LBD-BDNF) respectively. In this work, we developed laminin modified LOCS fibers (L × LOCS) by chemical cross-linking LOCS fibers with laminin. Collagen binding or laminin binding neurotrophic factors were combined with LOCS or L × LOCS, and then filled them into the collagen nerve conduit. They were found to guide the ordered growth of axons, and improve the nerve functional recovery in the rat facial nerve transection model. The combination of CNTF and BDNF greatly enhanced the facial nerve regeneration and functional recovery.

  2. Carbon dioxide laser-assisted nerve repair: effect of solder and suture material on nerve regeneration in rat sciatic nerve.

    PubMed

    Menovsky, Tomas; Beek, Johan F

    2003-01-01

    In order to further improve and explore the role of lasers for nerve reconstruction, this study was designed to investigate regeneration of sharply transected peripheral nerves repaired with a CO(2) milliwatt laser in combination with three different suture materials and a bovine albumin protein solder as an adjunct to the welding process. Unilateral sciatic nerve repair was performed in 44 rats. In the laser group, nerves were gently apposed, and two stay sutures (10-0 nylon, 10-0 polyglycolic acid, or 25 microm stainless steel) were placed epi/perineurially. Thereafter, the repair site was fused at 100 mW with pulses of 1.0 s. In the subgroup of laser-assisted nerve repair (LANR), albumen was used as a soldering agent to further reinforce the repair site. The control group consisted of nerves repaired by conventional microsurgical suture repair (CMSR), using 4-6 10-0 nylon sutures. Evaluation was performed at 1 and 6 weeks after surgery, and included qualitative and semiquantitative light microscopy. LANR performed with a protein solder results in a good early peripheral nerve regeneration, with an optimal alignment of nerve fibers and minimal connective tissue proliferation at the repair site. All three suture materials produced a foreign body reaction; the least severe was with polyglycolic acid sutures. CMSR resulted in more pronounced foreign-body granulomas at the repair site, with more connective-tissue proliferation and axonal misalignment. Furthermore, axonal regeneration in the distal nerve segment was better in the laser groups. Based on these results, CO(2) laser-assisted nerve repair with soldering in combination with absorbable sutures has the potential of allowing healing to occur with the least foreign-body reaction at the repair site. Further experiments using this combination are in progress.

  3. Age- and time-dependent effects on functional outcome and cortical activation pattern in patients with median nerve injury: a functional magnetic resonance imaging study.

    PubMed

    Fornander, Lotta; Nyman, Torbjörn; Hansson, Thomas; Ragnehed, Mattias; Brismar, Tom

    2010-07-01

    The authors conducted a study to determine age- and time-dependent effects on the functional outcome after median nerve injury and repair and how such effects are related to changes in the pattern of cortical activation in response to tactile stimulation of the injured hand. The authors studied 11 patients with complete unilateral median nerve injury at the wrist repaired with epineural suture. In addition, 8 patients who were reported on in a previous study were included in the statistical analysis. In the entire study cohort, the mean age at injury was 23.3 +/- 13.4 years (range 7-57 years) and the time after injury ranged from 1 to 11 years. Sensory perception was measured with the static 2-point discrimination test and monofilaments. Functional MR imaging was conducted during tactile stimulation (brush strokes) of Digits II-III and IV-V of both hands, respectively. Tactile sensation was diminished in the median territory in all patients. The strongest predictor of 2-point discrimination was age at injury (p < 0.0048), and when this was accounted for in the regression analysis, the other age- and time-dependent predictors had no effect. The activation ratios (injured/healthy hand) for Digit II-III and Digit IV-V stimulation were positively correlated (rho 0.59, p < 0.011). The activation ratio for Digit II-III stimulation correlated weakly with time after injury (p < 0.041). The activation ratio of Digits IV-V correlated weakly with both age at injury (p < 0.048) and time after injury (p < 0.033), but no predictor reached significance in the regression model. The mean ratio of ipsi- and contralateral hemisphere activation after stimulation of the injured hand was 0.55, which was not significantly different from the corresponding ratio of the healthy hand (0.66). Following a median nerve injury (1-11 years after injury) there may be an initial increase in the volume of the cortical representation, which subsequently declines during the restoration phase. These

  4. Blockade of median raphe nucleus α1-adrenoceptor subtypes increases food intake in rats.

    PubMed

    da Silva, Eduardo Simão; Flores, Rafael Appel; Cella, Elisa Carolina; Levone, Brunno Rocha; Taschetto, Ana Paula; Kochenborger, Larissa; Terenzi, Mariana Graciela; Faria, Moacir Serralvo; Paschoalini, Marta Aparecida

    2014-09-01

    Previous studies have shown that the blockade of α1-adrenoceptors in the median raphe nucleus (MnR) of free-feeding animals increases food intake. Since there is evidence for the presence of α1A-, α1B- and α1D-adrenoceptors in the MnR of rats, this study investigated the involvement of MnR α1-adrenoceptor subtypes in the control of feeding behavior, looking for possible differences on the role of each α1-adrenoceptor in feeding. Male adult rats weighing 280-300 g with guide cannulae chronically implanted above the MnR were injected with antagonists of α1A- (RS100329, 0, 2, 4 or 20 nmol), α1B- (Rec 15/2615, 0, 2, 4 or 20 nmol) or α1D-adrenoceptor (BMY 7378, 0, 2, 4 or 20 nmol). Subsequently, behavioral evaluation of ingestive and non-ingestive parameters was monitored for 1h and the amount of food and water ingested was assessed for 4h. The highest dose (20 nmol) of RS100329 and BMY 7378 increased food intake, feeding duration and frequency, and decreased the latency to start feeding. During the second hour 2 nmol dose of Rec 15/2615 increased food intake and all doses of BMY 7378 decreased water intake. No behavioral alterations were observed during the fourth hour. The results corroborate previous work from our lab in which we describe the involvement of α1-adrenoceptors of MnR on food intake control. Moreover, we show evidence that α1A- and α1D-adrenoceptors mediate feeding responses to adrenaline injections and that the behavioral modifications are of considerable duration, persisting up to 2h after injection of the antagonists. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Peripheral nerve regeneration following transection injury to rat sciatic nerve by local application of adrenocorticotropic hormone.

    PubMed

    Mohammadi, Rahim; Yadegarazadi, Mohammad-Javad; Amini, Keyvan

    2014-09-01

    The objective of this study was to assess local effect of adrenocorticotropic hormone (ACTH) on the functional recovery of the sciatic nerve in a transection model. Sixty male healthy white Wistar rats were randomized into four experimental groups of 15 animals each: In the sham-operated group (SHAM), the sciatic nerve was exposed and manipulated. In the transected group (TC), the left sciatic nerve was transected and the cut nerve ends were fixed in the adjacent muscle. In the silicone graft group (SIL) a 10-mm defect was made and bridged using a silicone tube. The graft was filled with phosphated-buffer saline alone. In the treatment group a silicone tube (SIL/ACTH) was filled with 10 μL ACTH (0.1 mg/mL). Each group was subdivided into three subgroups of five animals each and regenerated nerve fibres were studied at 4, 8 and 12 weeks post operation. Behavioral testing, functional, gastrocnemius muscle mass and morphometric indices showed earlier regeneration of axons in SIL/ACTH than in SIL group (p < 0.05). Immunohistochemistry clearly showed more positive location of reactions to S-100 in SIL/ACTH than in SIL group. ACTH improved functional recovery and morphometric indices of sciatic nerve. This finding supports role of ACTH after peripheral nerve repair and may have clinical implications for the surgical management of patients after nerve transection.

  6. Electrical stimulation accelerates nerve regeneration and functional recovery in delayed peripheral nerve injury in rats.

    PubMed

    Huang, Jinghui; Zhang, Yongguang; Lu, Lei; Hu, Xueyu; Luo, Zhuojing

    2013-12-01

    The present study aims to investigate the potential of brief electrical stimulation (ES; 3 V, 20 Hz, 20 min) in improving functional recovery in delayed nerve injury repair (DNIR). The sciatic nerve of Sprague Dawley rats was transected, and the repair of nerve injury was delayed for different time durations (2, 4, 12 and 24 weeks). Brief depolarizing ES was applied to the proximal nerve stump when the transected nerve stumps were bridged with a hollow nerve conduit (5 mm in length) after delayed periods. We found that the diameter and number of regenerated axons, the thickness of myelin sheath, as well as the number of Fluoro-Gold retrograde-labeled motoneurons and sensory neurons were significantly increased by ES, suggesting that brief ES to proximal nerve stumps is capable of promoting nerve regeneration in DNIR with different delayed durations, with the longest duration of 24 weeks. In addition, the amplitude of compound muscle action potential (gastrocnemius muscle) and nerve conduction velocity were also enhanced, and gastrocnemius muscle atrophy was partially reversed by brief ES, indicating that brief ES to proximal nerve stump was able to improve functional recovery in DNIR. Furthermore, brief ES was capable of increasing brain-derived neurotrophic factor (BDNF) expression in the spinal cord in DNIR, suggesting that BDNF-mediated neurotrophin signaling might be one of the contributing factors to the beneficial effect of brief ES on DNIR. In conclusion, the present findings indicate the potential of using brief ES as a useful method to improve functional recovery for delayed repair of peripheral nerve lesions. © 2013 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  7. Perineural dexmedetomidine effects on sciatic nerve in rat.

    PubMed

    Yektaş, Abdulkadir; Çabalar, Murat; Sar, Mehmet; Alagöl, Ayşin; Çelik, Duygu Sultan; Yayla, Vildan; Tolga, Deniz

    The present study was designed to test the hypothesis that high dose dexmedetomidine would increase the duration of antinociception to a thermal stimulus in a rat model of sciatic nerve blockade without causing nerve damage. The rats were anesthetized with isoflurane. After electromyography (EMG) recordings, right sciatic nerves were explored and perineural injections were delivered: Group D (n=7), 40μgμgkg(-1) dexmedetomidine administration, Group II (n=6), (0.2mL) saline administration, Group III (n=2), only surgically exploration of the right sciatic nevre. Time to paw withdrawal latency (PAW) to a thermal stimulus for both paws and an assessment of motor function were measured every 30min after the nerve block until a return to baseline. The compound muscle action potential (CMAP) of right and left sciatic nerves were recorded 10 times per each nerve once more after perineural injections at 14 day. After EMG recordings, right and the part of left sciatic nerve were excised at a length of at minimum 15mm for histopathological examination. Comparison of right/left CMAP amplitude ratios before and 14 days after the procedure showed a statistically significant difference (p=0.000). There were no differences in perineural inflammation between the Group D, Group S, and Group E at 14 days.

  8. [Perineural dexmedetomidine effects on sciatic nerve in rat].

    PubMed

    Yektaş, Abdulkadir; Çabalar, Murat; Sar, Mehmet; Alagöl, Ayşin; Çelik, Duygu Sultan; Yayla, Vildan; Tolga, Deniz

    The present study was designed to test the hypothesis that high dose dexmedetomidine would increase the duration of antinociception to a thermal stimulus in a rat model of sciatic nerve blockade without causing nerve damage. The rats were anesthetized with isoflurane. After electromyography (EMG) recordings, right sciatic nerves were explored and perineural injections were delivered: Group D (n=7), 40μgμgkg(-1) dexmedetomidine administration, Group II (n=6), (0.2mL) saline administration, Group III (n=2), only surgically exploration of the right sciatic nevre. Time to paw withdrawal latency (PAW) to a thermal stimulus for both paws and an assessment of motor function were measured every 30min after the nerve block until a return to baseline. The compound muscle action potential (CMAP) of right and left sciatic nerves were recorded 10 times per each nerve once more after perineural injections at 14 day. After EMG recordings, right and the part of left sciatic nerve were excised at a length of at minimum 15mm for histopathological examination. Comparison of right/left CMAP amplitude ratios before and 14 days after the procedure showed a statistically significant difference (p=0.000). There were no differences in perineural inflammation between the Group D, Group S, and Group E at 14 days.

  9. Curcumin promotes nerve regeneration and functional recovery after sciatic nerve crush injury in diabetic rats.

    PubMed

    Ma, Junxiong; Yu, Hailong; Liu, Jun; Chen, Yu; Wang, Qi; Xiang, Liangbi

    2016-01-01

    Curcumin is capable of promoting peripheral nerve regeneration in normal condition. However, it is unclear whether its beneficial effect on nerve regeneration still exists under diabetic mellitus. The present study was designed to investigate such a possibility. Diabetes in rats was developed by a single dose of streptozotocin at 50 mg/kg. Immediately after nerve crush injury, the diabetic rats were intraperitoneally administrated daily for 4 weeks with curcumin (50 mg/kg, 100 mg/kg and 300 mg/kg), or normal saline, respectively. The axonal regeneration was investigated by morphometric analysis and retrograde labeling. The functional recovery was evaluated by electrophysiological studies and behavioral analysis. Axonal regeneration and functional recovery was significantly enhanced by curcumin, which were significantly better than those in vehicle saline group. In addition, high doses of curcumin (100 mg/kg and 300 mg/kg) achieved better axonal regeneration and functional recovery than low dose (50 mg/kg). In conclusion, curcumin is capable of promoting nerve regeneration after sciatic nerve crush injury in diabetes mellitus, highlighting its therapeutic values as a neuroprotective agent for peripheral nerve injury repair in diabetes mellitus. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  10. Effect of Frankincense Extract on Nerve Recovery in the Rat Sciatic Nerve Damage Model

    PubMed Central

    Jiang, Xiaowen; Ma, Jun; Wei, Qingwei; Feng, Xinxin; Qiao, Lu; Liu, Lin; Zhang, Binqing; Yu, Wenhui

    2016-01-01

    This study investigated the effect of frankincense extract on peripheral nerve regeneration in a crush injury rat model. Forty-eight Sprague-Dawley rats were randomly divided into four groups: control and frankincense extract low-, medium-, and high-dose groups. At days 7, 14, 21, and 28 following the surgery, nerve regeneration and functional recovery were evaluated using the sciatic functional index (SFI), expression of GAP-43, and the proliferation of Schwann cells (SCs) in vivo and in vitro. At day 7, the SFI in the frankincense extract high-dose group was significantly improved compared with the control group. After day 14, SFI was significantly improved in the medium- and high-dose groups. There was no significant difference in GAP-43 expression among the groups at day 7. However, after day 14, expression of GAP-43 in the high-dose group was higher than that in the control group. Histological evaluation showed that the injured nerve of frankincense extract high-dose group recovered better than the other groups 28 days after surgery. Further, S100 immunohistochemical staining, MTT colorimetry, and flow cytometry assays all showed that frankincense extract could promote the proliferation of SCs. In conclusion, frankincense extract is able to promote sciatic nerve regeneration and improve the function of a crushed sciatic nerve. This study provides a new direction for the repair of peripheral nerve injury. PMID:27143985

  11. [Central projections of the rat recurrent laryngeal nerve].

    PubMed

    Pascual-Font, A; Maranillo, E; Merchán, A; Vázquez, T; Sañudo, J R; Valderrama-Canales, F J

    2006-01-01

    Laryngeal nerves contain the fibres that control the laryngeal function. The studies carried out on the rat with the purpose of having a better knowledge of the functional components and the real origin of the fibres conveyed by the recurrent laryngeal nerve (RLN) are few and in disagreement. No one of such papers were developed using biotinylated dextrane amines (BDA), a powerful tool for tracing neural pathways. The aim of our study was to identify in the rat using BDA, the nuclei of real origin of the fibres of the RLN, knowing in this way the functional components of this nerve. The study has been developed in 31 adult male Sprague-Dawley rats, applying the BDA into the lesioned RLN. The results obtained in all the animals show that the rat's RLN does not contain afferent fibres, whereas the efferent fibres were originated within the ipsilateral nucleus ambiguus (NA). So, in the rat, the RLN seems to contain exclusively efferent fibres, probably been the superior laryngeal nerve who conveyed the afferent fibres.

  12. Mandibular branch of the facial nerve in wistar rats: new experimental model to assess facial nerve regeneration.

    PubMed

    Bento, Ricardo Ferreira; Salomone, Raquel; Nascimento, Silvia Bona do; Ferreira, Ricardo Jose Rodriguez; Silva, Ciro Ferreira da; Costa, Heloisa Juliana Zabeu Rossi

    2014-07-01

    Introduction The ideal animal model for nerve regeneration studies is the object of controversy, because all models described by the literature have advantages and disadvantages. Objective To describe the histologic and functional patterns of the mandibular branch of the facial nerve of Wistar rats to create a new experimental model of facial nerve regeneration. Methods Forty-two male rats were submitted to a nerve conduction test of the mandibular branch to obtain the compound muscle action potential. Twelve of these rats had the mandibular branch surgically removed and submitted to histologic analysis (number, partial density, and axonal diameter) of the proximal and distal segments. Results There was no statistically significant difference in the functional and histologic variables studied. Conclusion These new histologic and functional standards of the mandibular branch of the facial nerve of rats establish an objective, easy, and greatly reproducible model for future facial nerve regeneration studies.

  13. Mandibular Branch of the Facial Nerve in Wistar Rats: New Experimental Model to Assess Facial Nerve Regeneration

    PubMed Central

    Bento, Ricardo Ferreira; Salomone, Raquel; Nascimento, Silvia Bona do; Ferreira, Ricardo Jose Rodriguez; Silva, Ciro Ferreira da; Costa, Heloisa Juliana Zabeu Rossi

    2014-01-01

    Introduction The ideal animal model for nerve regeneration studies is the object of controversy, because all models described by the literature have advantages and disadvantages. Objective To describe the histologic and functional patterns of the mandibular branch of the facial nerve of Wistar rats to create a new experimental model of facial nerve regeneration. Methods Forty-two male rats were submitted to a nerve conduction test of the mandibular branch to obtain the compound muscle action potential. Twelve of these rats had the mandibular branch surgically removed and submitted to histologic analysis (number, partial density, and axonal diameter) of the proximal and distal segments. Results There was no statistically significant difference in the functional and histologic variables studied. Conclusion These new histologic and functional standards of the mandibular branch of the facial nerve of rats establish an objective, easy, and greatly reproducible model for future facial nerve regeneration studies. PMID:25992106

  14. Inhibitory Effect of Acupuncture on Vibration-Induced Finger Flexion Reflex in Humans: Comparisons Among Radial, Median, and Ulnar Nerve Stimulation.

    PubMed

    Yajima, Hiroyoshi; Takayama, Miho; Kawase, Akiko; Takakura, Nobuari; Izumizaki, Masahiko; Homma, Ikuo

    2013-08-01

    Vibration-induced finger flexion reflex (VFR) is inhibited with acupuncture to TE 5 or LI 4 at the skin innervated by the radial nerve. The aim of this study was to determine if acupoints in regions innervated by the radial nerve are specific to inhibit VFR. This experiment was performed using a crossover design with 3 acupuncture groups (needle insertion to the right LU 11, PC 9, or SI 1) and a control group (no needle treatment). Each acupoint was randomly needled on separate days. Ten healthy volunteers were recruited for this study. VFR was induced by applying vibration on the volar side of the right middle fingertip. An acupuncture needle was inserted in the acupoint and retained for 5 minutes. For the main outcome measure, maximum finger flexion force (MFFF) was measured during vibration and was compared among four groups. MFFFs in the acupuncture groups were significantly lower (p<0.05) than that in the control group. However, no significant difference was observed in MFFFs in the three intervention groups after acupuncture to LU 11, PC 9, and SI 1. Acupuncture to the right LU 11, PC 9, or SI 1 point inhibited the ipsilateral VFR, which suggests that afferent inputs from the radial nerve with needle insertion were not specific, compared with those from the median and ulnar nerves to suppress neuronal activities in the VFR reflex circuits.

  15. 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

  16. Multidimensional ultrasound imaging of the wrist: Changes of shape and displacement of the median nerve and tendons in carpal tunnel syndrome.

    PubMed

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

    2015-09-01

    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. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  17. 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.

  18. 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.

  19. BA3b and BA1 activate in a serial fashion after median nerve stimulation: direct evidence from combining source analysis of evoked fields and cytoarchitectonic probabilistic maps.

    PubMed

    Papadelis, Christos; Eickhoff, Simon B; Zilles, Karl; Ioannides, Andreas A

    2011-01-01

    This study combines source analysis imaging data for early somatosensory processing and the probabilistic cytoarchitectonic maps (PCMs). Human somatosensory evoked fields (SEFs) were recorded by stimulating left and right median nerves. Filtering the recorded responses in different frequency ranges identified the most responsive frequency band. The short-latency averaged SEFs were analyzed using a single equivalent current dipole (ECD) model and magnetic field tomography (MFT). The identified foci of activity were superimposed with PCMs. Two major components of opposite polarity were prominent around 21 and 31 ms. A weak component around 25 ms was also identified. For the most responsive frequency band (50-150 Hz) ECD and MFT revealed one focal source at the contralateral Brodmann area 3b (BA3b) at the peak of N20. The component ~25 ms was localised in Brodmann area 1 (BA1) in 50-150 Hz. By using ECD, focal generators around 28-30 ms located initially in BA3b and 2 ms later to BA1. MFT also revealed two focal sources - one in BA3b and one in BA1 for these latencies. Our results provide direct evidence that the earliest cortical response after median nerve stimulation is generated within the contralateral BA3b. BA1 activation few milliseconds later indicates a serial mode of somatosensory processing within cytoarchitectonic SI subdivisions. Analysis of non-invasive magnetoencephalography (MEG) data and the use of PCMs allow unambiguous and quantitative (probabilistic) interpretation of cytoarchitectonic identity of activated areas following median nerve stimulation, even with the simple ECD model, but only when the model fits the data extremely well. Copyright © 2010 Elsevier Inc. All rights reserved.

  20. Carpal Tunnel Syndrome Assessment with Ultrasonography: Value of Inlet-to-Outlet Median Nerve Area Ratio in Patients versus Healthy Volunteers

    PubMed Central

    Liu, Fang; Zhu, Jiaan; Ye, Dongmei; Feng, Xianxuan; Xu, Yiming; Wang, Gang; Bai, Yuehong

    2015-01-01

    Objective To evaluate the diagnostic value of the Inlet-to-outlet median nerve area ratio (IOR) in patients with clinically and electrophysiologically confirmed carpal tunnel syndrome (CTS). Methods Forty-six wrists in 46 consecutive patients with clinical and electrodiagnostic evidence of CTS and forty-four wrists in 44 healthy volunteers were examined with ultrasonography. The cross-sectional area (CSA) of the median nerve was measured at the carpal tunnel inlet (the level of scaphoid-pisiform) and outlet (the level of the hook of the hamate), and the IOR was calculated for each wrist. Ultrasonography and electrodiagnostic tests were performed under blinded conditions. Electrodiagnostic testing combined with clinical symptoms were considered to be the gold standard test. Receiver operating characteristic (ROC) curves were used to evaluate the diagnostic value between the inlet CSA and IOR. Results The study population included 16 men and 30 women (mean age, 45.3 years; range, 18–83 years). The control population included 18 men and 26 women (mean age, 50.4 years; range, 18–79 years). The mean inlet CSA was 8.7 mm2 in healthy controls and 14.6mm2 in CTS group (P<0.001). The mean IOR in healthy volunteers (1.0) was smaller than that in patients (1.6, P<0.001). Receiver operating characteristic analysis revealed a diagnostic advantage to using the IOR rather than the inlet CSA (P<0.01). An IOR cutoff value of ≥ 1.3 would yield 93% specificity and 91% sensitivity in the diagnosis of CTS. Conclusion The IOR of median nerve area promises to be an effective means in the diagnosis of CTS. A large-scale, randomized controlled trial is required to determine how and when this parameter will be used. PMID:25617835

  1. Misdirection of regenerating motor axons after nerve injury and repair in the rat sciatic nerve model

    PubMed Central

    de Ruiter, Godard C. W.; Malessy, Martijn J. A.; Alaid, Awad O.; Spinner, Robert J.; Engelstad, JaNean K.; Sorenson, E. J.; Kaufman, K. R.; Dyck, Peter J.; Windebank, Anthony J.

    2010-01-01

    Misdirection of regenerating axons is one of the factors that can explain the poor results often found after nerve injury and repair. In this study, we quantified the degree of misdirection and the effect on recovery of function after different types of nerve injury and repair in the rat sciatic nerve model; crush injury, direct coaptation, and autograft repair. Sequential tracing with retrograde labeling of the peroneal nerve before and 8 weeks after nerve injury and repair was performed to quantify the accuracy of motor axon regeneration. Digital video analysis of ankle motion was used to investigate the recovery of function. In addition, serial compound action potential recordings and nerve and muscle morphometry were performed. In our study, accuracy of motor axon regeneration was found to be limited; only 71% (±4.9%) of the peroneal motoneurons were correctly directed 2 months after sciatic crush injury, 42% (±4.2%) after direct coaptation, and 25% (±6.6%) after autograft repair. Recovery of ankle motion was incomplete after all types of nerve injury and repair and demonstrated a disturbed balance of ankle plantar and dorsiflexion. The number of motoneurons from which axons had regenerated was not significantly different from normal. The number of myelinated axons was significantly increased distal to the site of injury. Misdirection of regenerating motor axons is a major factor in the poor recovery of nerves that innervate different muscles. The results of this study can be used as basis for developing new nerve repair techniques that may improve the accuracy of regeneration. PMID:18448099

  2. Cortical plasticity induced by different degrees of peripheral nerve injuries: a rat functional magnetic resonance imaging study under 9.4 Tesla

    PubMed Central

    2013-01-01

    Background Major peripheral nerve injuries not only result in local deficits but may also cause distal atrophy of target muscles or permanent loss of sensation. Likewise, these injuries have been shown to instigate long-lasting central cortical reorganization. Methods Cortical plasticity changes induced after various types of major peripheral nerve injury using an electrical stimulation technique to the rat upper extremity and functional magnetic resonance imaging (fMRI) were examined. Studies were completed out immediately after injury (acute stage) and at two weeks (subacute stage) to evaluate time affect on plasticity. Results After right-side median nerve transection, cortical representation of activation of the right-side ulnar nerve expanded intra-hemispherically into the cortical region that had been occupied by the median nerve representation After unilateral transection of both median and ulnar nerves, cortical representation of activation of the radial nerve on the same side of the body also demonstrated intra-hemispheric expansion. However, simultaneous electrical stimulation of the contralateral uninjured median and ulnar nerves resulted in a representation that had expanded both intra- and inter-hemispherically into the cortical region previously occupied by the two transected nerve representations. Conclusions After major peripheral nerve injury, an adjacent nerve, with similar function to the injured nerve, may become significantly over-activated in the cortex when stimulated. This results in intra-hemispheric cortical expansion as the only component of cortical plasticity. When all nerves responsible for a certain function are injured, the same nerves on the contralateral side of the body are affected and become significantly over-activated during a task. Both intra- and inter-hemispheric cortical expansion exist, while the latter dominates cortical plasticity. PMID:23659705

  3. Sulodexide prevents peripheral nerve damage in streptozotocin induced diabetic rats.

    PubMed

    Jin, Heung Yong; Lee, Kyung Ae; Song, Sun Kyung; Liu, Wei Jing; Choi, Ji Hae; Song, Chang Ho; Baek, Hong Sun; Park, Tae Sun

    2012-01-15

    We investigated whether sulodexide has additional protective effects against peripheral nerve damage caused by microvascular dysfunction in a rat model of diabetes. Female Sprague-Dawley (SD) rats were divided into the following 4 groups (n=7-9/group): Normal, Normal+Sulodexide (sulodexide 10mg/kg), diabetic group, and diabetic+Sulodexide (sulodexide 10mg/kg). We assessed current perception threshold, skin blood flow, superoxide dismutase, and proteinuria in experimental rats after oral administration of sulodexide for 20 weeks. We also performed morphometric analysis of sciatic nerves and intraepidermal nerve fibers of the foot. Superoxide dismutase activity in the blood and sciatic nerve were increased significantly after sulodexide treatment in the diabetic group. Current perception threshold was reduced at 2000 Hz (633.3 ± 24.15 vs 741.2 ± 23.5 μA, P<0.05) and skin blood flow was improved (10.90 ± 0.67 vs 8.85 ± 0.49 TPU, P<0.05) in the diabetic+Sulodexide group compared with the diabetic group. The mean myelinated axon area was significantly larger (56.6 ± 2.2 vs 49.8 ± 2.7 μm(2), P<0.05) and the intraepidermal nerve fiber density was significantly less reduced (6.27 ± 0.24 vs 5.40 ± 0.25/mm, P<0.05) in the diabetic+Sulodexide group compared to the diabetic group. Our results demonstrate that sulodexide exhibits protective effects against peripheral nerve damage in a rat experimental model of diabetes. Therefore, these findings suggest that sulodexide is a potential new therapeutic agent for diabetic peripheral neuropathy.

  4. Right median nerve electrical stimulation for acute traumatic coma (the Asia Coma Electrical Stimulation trial): study protocol for a randomised controlled trial.

    PubMed

    Wu, Xiang; Zhang, Chao; Feng, Junfeng; Mao, Qing; Gao, Guoyi; Jiang, Jiyao

    2017-07-10

    Traumatic brain injury (TBI) has become the most common cause of death and disability in persons between 15 and 30 years of age, and about 10-15% of patients affected by TBI will end up in a coma. Coma caused by TBI presents a significant challenge to neuroscientists. Right median nerve electrical stimulation has been reported as a simple, inexpensive, non-invasive technique to speed recovery and improve outcomes for traumatic comatose patients. This multicentre, prospective, randomised (1:1) controlled trial aims to demonstrate the efficacy and safety of electrical right median nerve stimulation (RMNS) in both accelerating emergence from coma and promoting long-term outcomes. This trial aims to enrol 380 TBI comatose patients to partake in either an electrical stimulation group or a non-stimulation group. Patients assigned to the stimulation group will receive RMNS in addition to standard treatment at an amplitude of 15-20 mA with a pulse width of 300 μs at 40 Hz ON for 20 s and OFF for 40 s. The electrical treatment will last for 8 h per day for 2 weeks. The primary endpoint will be the percentage of patients regaining consciousness 6 months after injury. The secondary endpoints will be Extended Glasgow Outcome Scale, Coma Recovery Scale-Revised and Disability Rating Scale scores at 28 days, 3 months and 6 months after injury; Glasgow Coma Scale, Glasgow Coma Scale Motor Part and Full Outline of Unresponsiveness scale scores on day 1 and day 7 after enrolment and 28 days, 3 months and 6 months after injury; duration of unconsciousness and mechanical ventilation; length of intensive care unit and hospital stays; and incidence of adverse events. Right median nerve electrical stimulation has been used as a safe, inexpensive, non-invasive therapy for neuroresuscitation of coma patients for more than two decades, yet no trial has robustly proven the efficacy and safety of this treatment. The Asia Coma Electrical Stimulation (ACES) trial has the

  5. Differences in risk factors for neurophysiologically confirmed carpal tunnel syndrome and illness with similar symptoms but normal median nerve function: a case-control study.

    PubMed

    Coggon, David; Ntani, Georgia; Harris, E Clare; Linaker, Cathy; Van der Star, Richard; Cooper, Cyrus; Palmer, Keith T

    2013-08-15

    To explore whether risk factors for neurophysiologically confirmed carpal tunnel syndrome (CTS) differ from those for sensory symptoms with normal median nerve conduction, and to test the validity and practical utility of a proposed definition for impaired median nerve conduction, we carried out a case-control study of patients referred for investigation of suspected CTS. We compared 475 patients with neurophysiological abnormality (NP+ve) according to the definition, 409 patients investigated for CTS but classed as negative on neurophysiological testing (NP-ve), and 799 controls. Exposures to risk factors were ascertained by self-administered questionnaire. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were estimated by logistic regression. NP+ve disease was associated with obesity, use of vibratory tools, repetitive movement of the wrist or fingers, poor mental health and workplace psychosocial stressors. NP-ve illness was also related to poor mental health and occupational psychosocial stressors, but differed from NP+ve disease in showing associations also with prolonged use of computer keyboards and tendency to somatise, and no relation to obesity. In direct comparison of NP+ve and NP-ve patients (the latter being taken as the reference category), the most notable differences were for obesity (OR 2.7, 95 % CI 1.9-3.9), somatising tendency (OR 0.6, 95% CI 0.4-0.9), diabetes (OR 1.6, 95% CI 0.9-3.1) and work with vibratory tools (OR 1.4, 95% CI 0.9-2.2). When viewed in the context of earlier research, our findings suggest that obesity, diabetes, use of hand-held vibratory tools, and repeated forceful movements of the wrist and hand are causes of impaired median nerve function. In addition, sensory symptoms in the hand, whether from identifiable pathology or non-specific in origin, may be rendered more prominent and distressing by hand activity, low mood, tendency to somatise, and psychosocial stressors at work. These differences in associations with

  6. Nerve Growth Factor Decreases in Sympathetic and Sensory Nerves of Rats with Chronic Heart Failure

    PubMed Central

    Lu, Jian

    2014-01-01

    Nerve growth factor (NGF) plays a critical role in the maintenance and survival of both sympathetic and sensory nerves. Also, NGF can regulate receptor expression and neuronal activity in the sympathetic and sensory neurons. Abnormalities in NGF regulation are observed in patients and animals with heart failure (HF). Nevertheless, the effects of chronic HF on the levels of NGF within the sympathetic and sensory nerves are not known. Thus, the ELISA method was used to assess the levels of NGF in the stellate ganglion (SG) and dorsal root ganglion (DRG) neurons of control rats and rats with chronic HF induced by myocardial infarction. Our data show for the first time that the levels of NGF were significantly decreased (P < 0.05) in the SG and DRG neurons 6–20 weeks after ligation of the coronary artery. In addition, a close relation was observed between the NGF levels and the left ventricular function. In conclusion, chronic HF impairs the expression of NGF in the sympathetic and sensory nerves. Given that sensory afferent nerves are engaged in the sympathetic nervous responses to somatic stimulation (i.e. muscle activity during exercise) via a reflex mechanism, our data indicate that NGF is likely responsible for the development of muscle reflex-mediated abnormal sympathetic responsiveness observed in chronic HF. PMID:24913185

  7. Two-Stage Nerve Graft in Severe Scar: A Time-Course Study in a Rat Model.

    PubMed

    Zadegan, Shayan Abdollah; Firouzi, Masoumeh; Nabian, Mohammad Hossein; Zanjani, Leila Oriady; Ashtiani, Ahmad Mohebbi; Kamrani, Reza Shahryar

    2015-04-01

    Peripheral nerve repair outcomes are suboptimal in the presence of severe soft tissue injury and excessive scarring paralleling the process in tendon reconstruction of the hand. Inspired by the advantages of the two-stage technique in tendon grafting and with encouraging preliminary results, we aimed to investigate the two-stage nerve grafting technique as an alternative method of secondary nerve repair. Thirty female rats (~200 g) were randomly distributed into two groups (n=15). A 15 mm gap was created in the sciatic nerve of the animals and an excessive extraneural scar was induced using the "mincing" method. In this method, a thin strip of muscle was removed, minced in a petri dish and returned to the peripheral nerve. In the two-stage nerve graft group, a silicone tube was interposed in the first stage. After 4 weeks, in the second stage, the silicone tube was removed and a median nerve autograft was interposed through the newly formed vascularized sheath. In the conventional graft group, two nerve ends were protected with silicone caps in the first stage. After 4 weeks the caps were removed and the median graft was interposed. Behavioral assessments were performed at week 15 after surgery with the withdrawal reflex latency (WRL) and extensor postural thrust (EPT) and at the 3, 6 and 15-week time points with the TOA (toe out angle). Masson Trichrome staining method was used for histological assessments at week 15. According to the EPT and WRL, the two-stage nerve graft showed significant improvement (P=0.020 and P=0.017 respectively). The TOA showed no significant difference between the two groups. The total vascular index was significantly higher in the two-stage nerve graft group (P<0.001). Two-stage nerve graft using a silicone tube enhances vascularity of the graft and improves functional recovery.

  8. [Central projections of the rat superior laryngeal nerve].

    PubMed

    Pascual-Font, A; Maranillo, E; Merchán, A; Vázquez, T; Safiudo, J R; Valderrama-Canales, F

    2006-01-01

    Laryngeal nerves contain the fibres that control the laryngeal function. On the rat, the studies on the functional components and the real origin of the fibres conveyed by the superior laryngeal nerve (SLN) are few. No one of such works were developed using biotinylated dextrane amines (BDA), a powerful tool for tracing neural pathways. The aim of our study was to identify by using BDA, in the rat, the nuclei of real origin of the fibres of the SLN, knowing in this way the functional components of this nerve. The study has been developed in 11 adult male Sprague-Dawley rats, applying the BDA into the damaged SLN. The results obtained in all the animals shown that the rat SLN carries efferent fibres originated within the ipsilateral nucleus ambiguous (NA) and dorsal nucleus of the vagus (DNV), and that afferent fibres reach the tractus solitari and the nucleus tractus solitari. So, in the rat, the SLN seems to convey efferent fibres from the NA and DNV and, probably, all the laryngeal afferent fibres.

  9. Contralateral trigeminal nerve lesion reduces polyneuronal muscle innervation after facial nerve repair in rats.

    PubMed

    Angelov, D N; Skouras, E; Guntinas-Lichius, O; Streppel, M; Popratiloff, A; Walther, M; Klein, J; Stennert, E; Neiss, W F

    1999-04-01

    Functional recovery after facial nerve surgery is poor. Axotomized motoneurons (hyperexcitable upon intracellular current injections, but unable to discharge upon afferent stimulation) outgrow supernumerary branches which are misrouted towards improper muscles. We hypothesized that alterations in the trigeminal input to axotomized electrophysiologically silent facial motoneurons might improve specificity of reinnervation. To test this we compared, in the rat, behavioural, electrophysiological, and morphological parameters after transection and suture of the buccal facial nerve (buccal-buccal anastomosis, BBA) with those after BBA plus excision of the ipsi- or contralateral infraorbital nerve (ION). After BBA, the mystacial vibrissae dropped and remained motionless until 18-21 days post operation (days PO). After BBA plus ipsilateral ION excision, there was no recovery of vibrissae whisking at all. Following BBA plus contralateral ION excision, full restoration of whisking occurred at 7-10 days PO. Electromyography of whiskerpad muscles showed normal waveform and amplitude was also most rapidly restored after BBA plus contralateral ION excision. Neuron counts after retrograde tracing showed that the intact buccal nerve contained axons of the superior (91%) and inferior (9%) buccolabial nerves. After BBA, the superior nerve comprised 56%, the inferior 21%, and 23% of the motoneurons projected within both nerves. After BBA plus ipsilateral ION excision, misdirection worsened and values changed to 48, 39 and 13%, respectively. After BBA plus contralateral ION excision, portions improved to 69, 23 and 8%. We conclude that, by reducing the redundant axon branching, lesion of contralateral ION provides the best conditions for recovery of vibrissae rhythmical whisking after reconstructive surgery on the facial nerve.

  10. Respiratory motor responses to cranial nerve afferent stimulation in rats.

    PubMed

    Hayashi, F; McCrimmon, D R

    1996-10-01

    It was hypothesized that, because rats appear to lack a prominent disynaptic projection from the dorsal respiratory group to phrenic motoneurons (Phr), they would lack the short-latency excitation of Phr output seen in cats in response to stimulation of some cranial nerve afferents. Single-pulse superior laryngeal nerve (SLN) stimulation elicited a short-latency bilateral excitation of glossopharyngeal (IX) and hypoglossal (XII) nerves and an ipsilateral excitation of pharyngeal branch of vagus (PhX) in 67% of rats, but no excitation of Phr. Vagus (X) stimulation elicited a bilateral excitation of Phr and a predominantly ipsilateral excitation of IX and PhX. Single-pulse stimulation of SLN or X also elicited longer-latency, bilateral decreases in activity of all recorded nerves. Repetitive stimulation (50 Hz) of SLN or X suppressed inspiratory activity and prolonged expiration. Lung inflation (7.5 cmH2O) inhibited Phr and PhX activity; X stimulation inhibited Phr but prolonged PhX activity. In conclusion, rats predictably lack the SLN-induced short latency Phr excitation but exhibit other short latency reflexes for which the underlying circuitry is not clear.

  11. Irreducible dorsal distal radius fracture-dislocation with accompanying dorsal displacement of flexor tendons and median nerve: A rare type of injury.

    PubMed

    Songür, Murat; Şahin, Ercan; Zehir, Sinan; Kalem, Mahmut

    2014-01-01

    High energy distal radius fractures may cause significant soft tissue injuries. Dorsal displacement of median nerve and flexor tendons to dorsal compartment between distal radioulnar joint was an unreported type of soft tissue injury. 35-Year male admitted following fall from height diagnosed as closed distal radius fracture with dorsal displacement. The patient had no flexion and extension of all fingers with loss of sensation. Radial artery pulse was not palpable. Radiography and CT imaging revealed distal radius fracture with dorsal displacement with dorsal carpal dislocation. After failure of closed reduction, operative treatment was performed. At surgery, flexor tendons and median nerve was found to be placed at dorsal compartment. Reduction of the soft tissues was facilitated by distraction of distal radioulnar joint. Dorsal displacement of volar structures as the result of fracture dislocation was found to be an unreported type of injury. Difficulty during reduction of dorsally displaced structures is an important feature of the case. For severely displaced and deformed distal radial fractures and fracture dislocations, threshold for operative treatment should be kept low. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. Modulation of postural tremors at the wrist by supramaximal electrical median nerve shocks in essential tremor, Parkinson's disease and normal subjects mimicking tremor.

    PubMed

    Britton, T C; Thompson, P D; Day, B L; Rothwell, J C; Findley, L J; Marsden, C D

    1993-10-01

    The response of postural wrist tremors to supramaximal median nerve stimulation was examined in patients with hereditary essential tremor (n = 10) and Parkinson's disease (n = 9), and in normal subjects mimicking wrist tremor (n = 8). The average frequency of on-going tremor was the same in all three groups. Supramaximal peripheral nerve shocks inhibited and then synchronised the rhythmic electromyographic (EMG) activity of all types of tremor. The duration of inhibition ranged from 90 to 210ms, varying inversely with the frequency of on-going tremor. There was no significant difference in mean duration of inhibition or in the timing of the first peak after stimulation on the average rectified EMG records between the three groups. The degree to which supramaximal peripheral nerve shocks could modulate the timing of rhythmic EMG bursts in the forearm flexor muscles was also quantified by deriving a resetting index. No significant difference in mean resetting index of the three groups was found. These results suggest that such studies cannot be used to differentiate between the common causes of postural wrist tremors.

  13. Refining the Sensory and Motor Ratunculus of the Rat Upper Extremity Using fMRI and Direct Nerve Stimulation

    PubMed Central

    Cho, Younghoon R.; Pawela, Christopher P.; Li, Rupeng; Kao, Dennis; Schulte, Marie L.; Runquist, Matthew L.; Yan, Ji-Geng; Matloub, Hani S.; Jaradeh, Safwan S.; Hudetz, Anthony G.; Hyde, James S.

    2008-01-01

    It is well understood that the different regions of the body have cortical representations in proportion to the degree of innervation. Our current understanding of the rat upper extremity has been enhanced using functional MRI (fMRI), but these studies are often limited to the rat forepaw. The purpose of this study is to describe a new technique that allows us to refine the sensory and motor representations in the cerebral cortex by surgically implanting electrodes on the major nerves of the rat upper extremity and providing direct electrical nerve stimulation while acquiring fMRI images. This technique was used to stimulate the ulnar, median, radial, and musculocutaneous nerves in the rat upper extremity using four different stimulation sequences that varied in frequency (5 Hz vs. 10 Hz) and current (0.5 mA vs. 1.0 mA). A distinct pattern of cortical activation was found for each nerve. The higher stimulation current resulted in a dramatic increase in the level of cortical activation. The higher stimulation frequency resulted in both increases and attenuation of cortical activation in different regions of the brain, depending on which nerve was stimulated. PMID:17969116

  14. [Morphometry of the recurrent laryngeal nerves of the rat].

    PubMed

    Pascual-Font, A; Merchán, A; Maranillo, E; Brillas, A; Sañudo, J R; Valderrama-Canales, F J

    2006-12-01

    In mammals the recurrent laryngeal nerves are dissimilar in length between both sides. This asymmetry involves different time of arrival of the stimulus to the laryngeal musculature controlled by each nerve. Thus, several explanations have been addressed to elucidate the closest of the glottis at the same time despite the unlike length of the nerves. However, previous works on the topic lack of several important data. The present study compares, in two groups of 10 and 6 rats, the length and the composition of myelinated fibers in the recurrent laryngeal nerves of both sides, by means of light microscopy and a computerized morphometric analysis. The results show a mean difference of 0,84 cm longer the left than the right recurrent laryngeal nerve. No statistical differences were observed in the number of myelinated fibers between both sides. However, the myelinated fibers of the right side were statistically bigger in diameter than the fibers of the left side. The data are discussed in the context of the mechanisms for the compensation of the dissimilar length of both recurrent laryngeal nerves.

  15. Low-energy laser action on median and radial nerve post-traumatic lesion after surgical suture

    NASA Astrophysics Data System (ADS)

    Antipa, Ciprian; Bunila, Daniela; Crangulescu, Nicolae; Nacu, Mihaela; Podoleanu, Adrian Gh.; Stanciulescu, Viorica; Vasiliu, Virgil V.

    1996-01-01

    The low energy laser (LEL) biostimulatory effects on nervous tissue regeneration are well known. Thirty two patients with medial and/or radial nerve traumatic forearm lesion after surgical suture were divided into two groups: A-18 patients were treated with LEL; B-14 patients, witness, were treated with placebo lasers and classical medical and physical therapy. Lasers used were: HeNe, 632.5 nm wavelength, 2 mW power, and GaAlAs diode laser, 880 nm wavelength, pulsed emission with an output power 2 mW. Before, during, and after treatment EMG was done in order to measure objectively the efficiency of the treatment. We obtained good results after 4 - 5 months at 14 patients (77.7%) from group A and about the same results at 10 patients (71.3%) from group B, but after at least 8 months the good results were noticed concerning the improvements of EMG registration and on movements and force of the fingers. Finally we can say that the favorable results were obtained in at least twice shorter time with LEL treatment than with classical therapy.

  16. (-)-Epigallocatechin-3-gallate (EGCG) attenuates peripheral nerve degeneration in rat sciatic nerve crush injury.

    PubMed

    Renno, Waleed M; Al-Maghrebi, May; Alshammari, Ahmad; George, Preethi

    2013-02-01

    Recently, we have shown that green tea (GT) consumption improves both reflexes and sensation in unilateral chronic constriction injury to the sciatic nerve. Considering the substantial neuroprotective properties of GT polyphenols, we sought to investigate whether (-)-epigallocatechin-3-gallate (EGCG) could protect the sciatic nerve and improve functional impairments induced by a crushing injury. We also examined whether neuronal cell apoptosis induced by the crushing injury is affected by EGCG treatment. Histological examination of sciatic nerves from EGCG-treated (50mg/kg; i.p.) showed that axonotmized rats had a remarkable axonal and myelin regeneration with significant decrease in the number of myelinated axonal fibers compared to vehicle-treated crush group. Similarly, ultrastructural evaluation of EGCG-treated nerves displayed normal unmyelinated and myelinated axons with regular myelin sheath thickness and normalized appearance of Schmidt-Lantermann clefts. Extracellular matrix displayed normal collagen fibers appearance with distinctively organized distribution similar to sham animals. Analysis of foot position and extensor postural thrust test showed a progressive and faster recovery in the EGCG-treated group compared to vehicle-treated animals. EGCG-treated rats showed significant increase in paw withdrawal thresholds to mechanical stimulation compared to vehicle-treated crush group. EGCG treatment also restored the mRNA expression of Bax, Bcl-2 and survivin but not that of p53 to sham levels on days 3 and 7 post-injury. Our results demonstrate that EGCG treatment enhanced functional recovery, advanced morphological nerve rescue and accelerated nerve regeneration following crush injury partly due to the down regulation of apoptosis related genes.

  17. IDPN impairs post-traumatic regeneration of rat sciatic nerve.

    PubMed

    Morbin, M; Monaco, S; Zanette, G; Rizzuto, N

    1993-12-01

    The role played by cytoskeletal proteins in nerve regeneration was investigated in a model in which the axonal transport of neurofilaments (NF) is almost selectively impaired. The administration of beta, beta'-iminodipropionitrile (IDPN), a synthetic lathyrogenic compound, induces an axonopathy characterized by proximal axonal enlargements, due to NF accumulation, and by diffuse atrophic changes associated with spatial segregation of NF from microtubules (MT). We investigated post-axotomy regeneration of rat sciatic nerve following IDPN administration. Changes induced by IDPN, as examined in the proximal and distal nerve stump at 15 and 30 days after lesion, consisted of a statistically significant reduction of the mean axonal diameter (P < 0.0001) as compared to control rats. In addition, the number of regenerating myelinated fibres was smaller in dosed rats (P < 0.001) 15 days after crush, whereas at the later stage the number of axons approached that of control animals. Electrophysiological investigation revealed a delay in target reinnervation in dosed rats. Regenerating IDPN axons, both 15 and 30 days after crush contained fewer NF (P < 0.001), while the number of MT was slightly increased as compared to controls. Taken together, our results suggest that severe alteration of NF transport, coupled with mild alteration of other components of cytoskeletal proteins, impairs the longitudinal and radial growth of regenerating myelinated axons and confirm that the number of NF is the major determinant of the cross-sectional area of each segment of the axon.

  18. Using multiple high-count electrode arrays in human median and ulnar nerves to restore sensorimotor function after previous transradial amputation of the hand.

    PubMed

    Clark, Gregory A; Wendelken, Suzanne; Page, David M; Davis, Tyler; Wark, Heather A C; Normann, Richard A; Warren, David J; Hutchinson, Douglas T

    2014-01-01

    Peripheral nerve interfaces that can record from and stimulate large numbers of different nerve fibers selectively and independently may help restore intuitive and effective motor and sensory function after hand amputation. To this end, and extending previous work in two subjects, two 100-electrode Utah Slanted Electrode Arrays (USEAs) were implanted for four weeks in the residual ulnar and median nerves of a 50-year-old male whose left, dominant hand had been amputated 21 years previously. Subsequent experiments involved 1) recording from USEAs for real-time control of a virtual prosthetic hand; 2) stimulation to evoke somatosensory percepts; and 3) closed-loop sensorimotor control. Overall, partial motor control and sensation were achieved using USEAs. 1) Isolated action potentials recorded from nerve motor fibers, although sparse at these distal implant sites, were activated during fictive movements of the phantom hand. Unlike in our previous two subjects, electromyographic (EMG) activity contributed to most online recordings and decodes, but was reduced in offline analyses using common average referencing. Online and offline Kalman-filter decodes of thresholded neural or EMG spikes independently controlled different digits of the virtual hand with one or two degrees of freedom. 2) Microstimulation through individual electrodes of the two USEAs evoked up to 106 different percepts, covering much of the phantom hand. The subject discriminated among five perceived stimulus locations, and between two somatosensory submodalities at a single location. 3) USEA-evoked percepts, mimicking contact with either a near or distal virtual target, were used to terminate movements of the virtual hand controlled with USEA recordings comprised wholly or mostly of EMG. These results further indicate that USEAs can help restore sensory and motor function after hand loss.

  19. Behavioral evaluation of regenerated rat sciatic nerve by a nanofibrous PHBV conduit filled with Schwann cells as artificial nerve graft.

    PubMed

    Biazar, Esmaeil; Heidari Keshel, Saeed; Pouya, Majid

    2013-10-01

    The aim of this study is to develop a nanofibrous polymeric nerve conduit with Schwann cells (SCs) and to evaluate its efficiency on the promotion of functional and locomotive activities in rats. The conduits were implanted into a 30-mm gap in the sciatic nerves of the rats. Four months after surgery, the rats were monitored and evaluated by behavioral analyses such as toe out angle, toe spreading analysis, walking track analysis, extensor postural thrust, open-field analysis, swimming test and nociceptive function, four months post surgery. Four months post-operatively, the results from behavioral analyses demonstrated that in the grafted groups especially in the grafted group with SCs, the rat sciatic nerve trunk had been reconstructed with functional recovery such as walking, swimming and recovery of nociceptive function. This study proves the feasibility of artificial conduit with SCs for nerve regeneration by bridging a longer defect in the rat model.

  20. Plexin a4 expression in adult rat cranial nerves.

    PubMed

    Gutekunst, Claire-Anne; Gross, Robert E

    2014-11-01

    PlexinsA1-A4 participate in class 3 semaphorin signaling as co-receptors to neuropilin 1 and 2. PlexinA4 is the latest member of the PlexinA subfamily to be identified. In previous studies, we described the expression of PlexinA4 in the brain and spinal cord of the adult rat. Here, antibodies to PlexinA4 were used to reveal immunolabeling in most of the cranial nerve surveyed. Labeling was found in the olfactory, optic, oculomotor, trochlear, trigeminal, abducens, facial, vestibulocochlear, glossopharyngeal, vagus, and hypoglossal nerves. This is the first detailed description of the cellular and subcellular distribution of PlexinA4 in the adult cranial nerves. The findings will set the basis for future studies on the potential role of PlexinA4 in regeneration and repair of the adult central and peripheral nervous system. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Degeneration and regeneration of motor and sensory nerves: a stereological study of crush lesions in rat facial and mental nerves.

    PubMed

    Barghash, Z; Larsen, J O; Al-Bishri, A; Kahnberg, K-E

    2013-12-01

    The aim of this study was to evaluate the degeneration and regeneration of a sensory nerve and a motor nerve at the histological level after a crush injury. Twenty-five female Wistar rats had their mental nerve and the buccal branch of their facial nerve compressed unilaterally against a glass rod for 30s. Specimens of the compressed nerves and the corresponding control nerves were dissected at 3, 7, and 19 days after surgery. Nerve cross-sections were stained with osmium tetroxide and toluidine blue and analysed using two-dimensional stereology. We found differences between the two nerves both in the normal anatomy and in the regenerative pattern. The mental nerve had a larger cross-sectional area including all tissue components. The mental nerve had a larger volume fraction of myelinated axons and a correspondingly smaller volume fraction of endoneurium. No differences were observed in the degenerative pattern; however, at day 19 the buccal branch had regenerated to the normal number of axons, whereas the mental nerve had only regained 50% of the normal number of axons. We conclude that the regenerative process is faster and/or more complete in the facial nerve (motor function) than it is in the mental nerve (somatosensory function).

  2. Compound action potential of sensory tail nerves in the rat.

    PubMed

    Leandri, Massimo; Saturno, Moreno; Cilli, Michele; Bisaglia, Michela; Lunardi, Gianluigi

    2007-01-01

    Assessment of the conduction velocity of motor fibers of the rat tail nerves has been used by some authors in the past, but very little is known about the sensory fibers. In 10 adult rats, weighing between 320 and 380 g, responses from the nerves and muscles of the tail have been recorded after stimulation at its root and tip. It was found that stimulation of the tip involved mainly sensory fibers, of which two main groups could be identified. One faster group, conducting within the range of 38-27 m/s, and one slower group with range 14-7 m/s. The bipolar recording configuration was found to be optimal for sensory recording. Stimulation of the tail root evoked a motor response, which was preceded by a very small neurographic activity, due to the fastest sensory fibers conducting antidromically. The conduction velocity of motor fibers was calculated to be approximately 19 m/s. Distance traveled by the volley can be assessed with excellent precision on the tail nerves; hence the calculated conduction velocities are highly reliable and reproducible. We propose that the tail nerves may be a useful tool for evaluation of conduction velocity of Abeta and Adelta afferents. As the technique is just minimally invasive, the test can be repeated a number of times in animals under chronic experimental conditions.

  3. Treadmill training combined with insulin suppresses diabetic nerve pain and cytokines in rat sciatic nerve.

    PubMed

    Chen, Yu-Wen; Chiu, Chong-Chi; Hsieh, Pei-Ling; Hung, Ching-Hsia; Wang, Jhi-Joung

    2015-07-01

    Insulin therapy plays a critical role in managing type 1 diabetes mellitus, and exercise produces alterations in pain sensation. This experiment explored the effects of insulin therapy combined with treadmill training on diabetic neuropathic pain and on the expression of malondialdehyde (MDA) and cytokines. Rats were given 4 weeks of insulin (100 IU/kg) therapy and treadmill training (30-60 min/d of training at 20-25 m/min) each day beginning on day 3 after streptozotocin (65 mg/kg, IV) injection and continuing until day 27. Sensitivity to heat and mechanical stimuli and the expression of interleukin (IL)-10, IL-6, tumor necrosis factor-α, and MDA in the sciatic nerve were estimated. We showed that 2 to 4 weeks of treadmill training, insulin treatment, or their combination increased both paw withdrawal thresholds and latencies compared with the same regimen in sedentary diabetic rats (all P < 0.0022). Treatment with insulin, but without treadmill training, had significant effects on glycemic control (P < 0.0001) and restored body weight (P < 0.0001) in the diabetic rats. The diabetic rats demonstrated the upregulation (all P < 0.009) of IL-6, MDA, and tumor necrosis factor-α in the sciatic nerve on days 14 and 28 after streptozotocin treatment, whereas in diabetic rats receiving insulin, treadmill training, or a combination (all P < 0.01), this upregulation was decreased. Insulin, treadmill training, or the combination increased IL-10 expression (all P < 0.0051) in all diabetic rats. Treadmill training combined with insulin therapy showed the best improvements in tactile allodynia and thermal hyperalgesia among our 3 treatment groups. The benefits of insulin intervention and treadmill training could be related to chronic inflammation (proinflammatory cytokines) and oxidative stress (MDA).

  4. Strain differences in the branching of the sciatic nerve in rats.

    PubMed

    Rupp, A; Schmahl, W; Lederer, W; Matiasek, K

    2007-06-01

    The sciatic nerve in the rat is the site most often used for peripheral nerve regeneration studies. The length of sciatic nerve available for research, however, depends on the point at which the sciatic nerve divides into the peroneal and tibial nerves. In the present study, the hind limbs of 150 adult male rats of five different strains (Sprague-Dawley, Fischer 344, Wistar-Han, Lewis and Nude) were analysed with regard to femur length, the point at which the sciatic nerve divides into the tibial and peroneal nerves, and where these are surrounded by the same epineurium, and the point at which they are encased in individual epineurial sheaths. The results indicate that the lengths of sciatic nerve are fairly constant in all strains of rats. In absolute terms, they amount to about one-third of the length of the femur for stretches of undivided sciatic nerve, and up to nearly half of the femur length for stretches where the tibial and peroneal nerves are already present, but are still enclosed by the same epineurium. In 61.7% of the hind limbs examined in Fischer rats, however, no sciatic nerve could be seen as such, but only in the form of its successors surrounded by the separate epineuria. This makes it highly advisable not to use male adult Fischer rats in peripheral nerve regeneration studies with the sciatic nerve as the point of focus.

  5. Low-Level Laser Irradiation Improves Functional Recovery and Nerve Regeneration in Sciatic Nerve Crush Rat Injury Model

    PubMed Central

    Wang, Chau-Zen; Chen, Yi-Jen; Wang, Yan-Hsiung; Yeh, Ming-Long; Huang, Mao-Hsiung; Ho, Mei-Ling; Liang, Jen-I; Chen, Chia-Hsin

    2014-01-01

    The development of noninvasive approaches to facilitate the regeneration of post-traumatic nerve injury is important for clinical rehabilitation. In this study, we investigated the effective dose of noninvasive 808-nm low-level laser therapy (LLLT) on sciatic nerve crush rat injury model. Thirty-six male Sprague Dawley rats were divided into 6 experimental groups: a normal group with or without 808-nm LLLT at 8 J/cm2 and a sciatic nerve crush injury group with or without 808-nm LLLT at 3, 8 or 15 J/cm2. Rats were given consecutive transcutaneous LLLT at the crush site and sacrificed 20 days after the crush injury. Functional assessments of nerve regeneration were analyzed using the sciatic functional index (SFI) and hindlimb range of motion (ROM). Nerve regeneration was investigated by measuring the myelin sheath thickness of the sciatic nerve using transmission electron microscopy (TEM) and by analyzing the expression of growth-associated protein 43 (GAP43) in sciatic nerve using western blot and immunofluorescence staining. We found that sciatic-injured rats that were irradiated with LLLT at both 3 and 8 J/cm2 had significantly improved SFI but that a significant improvement of ROM was only found in rats with LLLT at 8 J/cm2. Furthermore, the myelin sheath thickness and GAP43 expression levels were significantly enhanced in sciatic nerve-crushed rats receiving 808-nm LLLT at 3 and 8 J/cm2. Taken together, these results suggest that 808-nm LLLT at a low energy density (3 J/cm2 and 8 J/cm2) is capable of enhancing sciatic nerve regeneration following a crush injury. PMID:25119457

  6. Low-level laser irradiation improves functional recovery and nerve regeneration in sciatic nerve crush rat injury model.

    PubMed

    Wang, Chau-Zen; Chen, Yi-Jen; Wang, Yan-Hsiung; Yeh, Ming-Long; Huang, Mao-Hsiung; Ho, Mei-Ling; Liang, Jen-I; Chen, Chia-Hsin

    2014-01-01

    The development of noninvasive approaches to facilitate the regeneration of post-traumatic nerve injury is important for clinical rehabilitation. In this study, we investigated the effective dose of noninvasive 808-nm low-level laser therapy (LLLT) on sciatic nerve crush rat injury model. Thirty-six male Sprague Dawley rats were divided into 6 experimental groups: a normal group with or without 808-nm LLLT at 8 J/cm(2) and a sciatic nerve crush injury group with or without 808-nm LLLT at 3, 8 or 15 J/cm(2). Rats were given consecutive transcutaneous LLLT at the crush site and sacrificed 20 days after the crush injury. Functional assessments of nerve regeneration were analyzed using the sciatic functional index (SFI) and hindlimb range of motion (ROM). Nerve regeneration was investigated by measuring the myelin sheath thickness of the sciatic nerve using transmission electron microscopy (TEM) and by analyzing the expression of growth-associated protein 43 (GAP43) in sciatic nerve using western blot and immunofluorescence staining. We found that sciatic-injured rats that were irradiated with LLLT at both 3 and 8 J/cm(2) had significantly improved SFI but that a significant improvement of ROM was only found in rats with LLLT at 8 J/cm(2). Furthermore, the myelin sheath thickness and GAP43 expression levels were significantly enhanced in sciatic nerve-crushed rats receiving 808-nm LLLT at 3 and 8 J/cm(2). Taken together, these results suggest that 808-nm LLLT at a low energy density (3 J/cm(2) and 8 J/cm(2)) is capable of enhancing sciatic nerve regeneration following a crush injury.

  7. Gait analysis in rats with peripheral nerve injury.

    PubMed

    Yu, P; Matloub, H S; Sanger, J R; Narini, P

    2001-02-01

    Rats are commonly used to study peripheral nerve repair and grafting. The traditional footprint method to assess functional recovery is messy, indirect, and not useful when contractures develop in the animal model. The aim of the present study was to establish an accurate, reproducible, but simple, method to assess dynamic limb function. The basic quantitative aspects of a normal gait were characterized from 59 recorded walks in 23 rats. The video was digitized and analyzed frame by frame on a personal computer. Seven parameters of the gait were assessed: (1) walking speed; (2) stance phase, swing phase and right to left stance/swing ratio; (3) step length and step length ratio; (4) ankle angles at terminal stance and midswing; (5) tail height; (6) midline deviation; and (7) tail deviation. These gait parameters were then applied to groups of animals with sciatic (group S), tibial (group T), and peroneal (group P) nerve injuries. A discriminant analysis was performed to analyze each parameter and to compute a functional score. We found that the video gait analysis was superior to the footprint method and believe it will be very useful in future studies on peripheral nerve injury.

  8. Therapeutic ultrasound after sciatic nerve compression of Wistar rats.

    PubMed

    Bertolini, Gladson Ricardo Flor; Karvat, Jhenifer; Kakihata, Camila Mayumi Martin; Ribeiro, Lucinéia de Fátima Chasko; Brancalhão, Rose Meire Costa

    2017-09-01

    The present study analyzed the effect of therapy with therapeutic ultrasound on the sciatic nerve after compression injury, comparing two similar doses of SATA. In total, 32 Wistar rats were used, divided into the following groups: CG - control; IG - compression injury of the sciatic nerve; IGCU - injury and continuous ultrasound; and IGPU - injury and 20% pulsed ultrasound. The treatment with ultrasound started on the 3rd postoperative day, with a frequency of 1 MHz, 0.4 W/cm² (SATA) for IGCU. IGPU received 2.0 W/cm(2) (SATP), with 20% of the active cycle, for 3 minutes. The treatment was performed on a daily basis, totaling 15 days of therapy. Evaluations were performed for functional, histological, and morphometric forms. Both the Sciatic Functional Index and the withdrawal threshold and grip strength failed to show an advantage of using therapeutic ultrasound. For the morphometric evaluations of nerve fiber diameter and axons, myelin sheath thickness, and G quotient and nerve fiber estimates, IGPU values were estimated to be significantly lower. The morphological analysis revealed intense inflammatory response and neovascularization, as well as degeneration of axons and the myelin sheath, for the injury group and IGCU; however, IGPU showed greater tissue disorganization. There were no significant differences, showing functional or nocicepitive recovery of the treated groups, including with characteristics pointing to the pulsed group with worse results.

  9. Increased expression of Gem after rat sciatic nerve injury.

    PubMed

    Wang, Youhua; Cheng, Xinghai; Zhou, Zhengming; Wu, Hao; Long, Long; Gu, Xingxing; Xu, Guangfei

    2013-02-01

    Gem belongs to the Rad/Gem/Kir subfamily of Ras-related GTPases, whose expression is induced in several cell types upon activation by extracellular stimuli. Two functions of Gem have been demonstrated, including regulation of voltage-gated calcium channel activity and inhibition of Rho kinase-mediated cytoskeletal reorganization, such as stress fiber formation and neurite retraction. Because of the essential relationship between actin reorganization and peripheral nerve regeneration, we investigated the spatiotemporal expression of Gem in a rat sciatic nerve crush (SNC) model. After never injury, we observed that Gem had a significant up-regulation from 1 day, peaked at day 5 and then gradually decreased to the normal level. At its peak expression, Gem expressed mainly in Schwann cells (SCs) and macrophages of the distal sciatic nerve segment, but had few colocalization in axons. In addition, the peak expression of Gem was in parallel with PCNA, and numerous SCs expressing Gem were PCNA positive. Thus, all of our findings suggested that Gem may be involved in the pathophysiology of sciatic nerve after SNC.

  10. Hippocampal EEG and Unit Activity Responses to Modulation of Serotonergic Median Raphe Neurons in the Freely Behaving Rat

    PubMed Central

    Nitz, Douglas A.; McNaughton, Bruce L.

    1999-01-01

    Hippocampal EEG, GABAergic interneurons, and principal cells were recorded simultaneously as rats foraged within one of three environments both before and after modulation of serotonergic inputs to the hippocampus. Median raphe microinjections of the 5-HT1a receptor agonist 8-OH-DPAT were made to produce inhibition of serotonergic neurons in this region. Such microinjections produced behavioral arousal and increases in the amplitude of hippocampal EEG theta. Consistent with the pattern of serotonergic innervation of the hippocampus, the GABAergic interneuron population was affected differentially by the microinjections. Principal cells were generally unaffected by the manipulation and maintained robust spatial firing correlates within the foraging environment. The results provide basic data on the relationship between serotonergic median raphe neurons and hippocampal activity in a behaving animal. The data suggest that behavioral responses to manipulation of the serotonergic system are mediated by brain regions other than the hippocampus or are mediated through changes in the activity of hippocampal interneurons. PMID:10327240

  11. Age-related ultrastructural and monoamine oxidase changes in the rat optic nerve.

    PubMed

    Taurone, S; Ripandelli, G; Minni, A; Lattanzi, R; Miglietta, S; Pepe, N; Fumagalli, L; Micera, A; Pastore, F S; Artico, M

    2016-01-01

    The aim of this paper is to study the morphology and the distribution of the monoamine oxidase enzymatic system in the optic nerve of 4 month-old Wistar (young) and 28 month-old Wistar (old) rats. The optic nerve was harvested from 20 young and old rats. The segment of optic nerve was divided longitudinally into two pieces, each 0.1 mm in length. The first piece was used for transmission electron microscopy. The second piece was stained with histochemical reaction for monoamine oxidase. The agerelated changes in the optic nerve of rats include micro-anatomical details, ultrastructure and monoamine oxidase histochemical staining. A strong decrease of the thin nerve fibers and a swelling of the thick ones can be observed in optic nerve fibers of old rats. Increased monoamine oxidase histochemical staining of the optic nerve of aged rats is well demonstrated. The increase of meningeal shealth and the decrease of thin nerve fibers of the optic nerve in old rats are well documented. Morphological, ultrastructural and histochemical changes observed in optic nerve fibers of the old rats show a close relation with aging.

  12. Conditioned place preference for mating is preserved in rats with pelvic nerve transection

    PubMed Central

    Meerts, Sarah H.; Clark, Ann S.

    2009-01-01

    Female rats exhibit a conditioned place preference (CPP) for a context paired with mating. The present experiment tested the hypothesis that the activation of the pelvic nerve mediates the reinforcing effects of mating for female rats. Rats underwent bilateral pelvic nerve or sham transection and then received paced mating, nonpaced mating or the control treatment during a CPP procedure. Pelvic nerve transection did not affect the CPP for paced or nonpaced mating. In tests of paced mating behavior, contact-return latencies following intromissions were significantly shorter in rats with pelvic nerve transection than rats with sham transections. These results show that the pathway conveying the reinforcing effects of mating stimulation does not depend on the integrity of the pelvic nerve, but that activation of the pelvic nerve contributes to the display of paced mating behavior. PMID:19485560

  13. Nerve reconstruction with glycerol-preserved allogenic grafts in the rat.

    PubMed

    Wolff, K D; Walter, G; Zimmer, C

    1993-01-01

    A variety of materials have been evaluated as potential nerve grafts. To date, none has been shown to be consistently equal with regard to functional outcome when compared to standard autogenous nerve grafts. In this study, nerves stored in glycerol were evaluated for their peripheral nerve regenerative capacity. Femoral nerves were harvested from Fischer rats and stored for a minimum of 100 days in 98% glycerol at 4 degrees C. They were grafted into femoral nerve gaps of Lewis rats. After 3 months, histologic, electrophysiologic, and morphometric (axon diameter) analyses revealed less regenerative response than nerve gaps grafted with fresh, syngeneic controls. The differences disappeared by 6 months, although neither graft technique achieved recovery comparable to unoperated nerves. Immunohistochemical evaluation demonstrated a modest immune response at 3 months, which subsided by 6 months. These findings are encouraging for the development of glycerol-preserved nerve graft banking.

  14. A variation of the cords of the brachial plexus on the right and a communication between the musculocutaneous and median nerves on the left upper limb: a unique case.

    PubMed

    Kirazlı, Özlem; Tatarlı, Necati; Ceylan, Davut; Hacıoğlu, Hüsniye; Uygun, Seda; Şeker, Aşkın; Keleş, Evren; Çavdar, Safiye

    2013-12-01

    During routine anatomical dissection of the upper extremity of a 64-year-old cadaver for educational purposes, we observed variations in the brachial plexus on each side. On the right an anomaly of cord formation was present and on the left there was a communication between the musculocutaneous nerve (MCN) and median nerve (MN). On the right side the brachial plexus showed two trunks, superior (C5 and C6) and inferior (C7, C8, and T1); the middle trunk was absent. The superior trunk bifurcated into anterior and posterior divisions, the anterior division continued as the lateral cord forming the MCN. The posterior division gave off the subscapular branch. The inferior trunk trifurcated into radial, median, and ulnar nerves. The radial nerve gave off the axillary and thoracodorsal nerves. The ulnar nerve gave off the median cutaneous nerves of the arm and forearm. The median nerve received a small ascending branch from the MCN. On the right side, there was a communicating branch from the MCN to the MN in the lower third of the arm region. This communicating branch also gave rise to a muscular branch to the brachialis muscle and the lateral cutaneous nerve of forearm. No additional heads of the biceps brachii muscle were observed in either upper limb. Knowledge of the variations of the brachial plexus in humans can be valuable for operations of the shoulder joint and its repair for providing an effective block or treatment for anesthetists and also for explaining otherwise incomprehensible clinical signs for neurologists. Georg Thieme Verlag KG Stuttgart · New York.

  15. Spinal cord projections of the rat main forelimb nerves, studied by transganglionic transport of WGA-HRP and by the disappearance of acid phosphatase.

    PubMed

    Castro-Lopes, J M; Coimbra, A

    1991-03-01

    The spinal cord projections of the 3 main forelimb nerves-median, radial and ulnar, were studied in the rat dorsal horn with transganglionic transport of wheat germ agglutinin-horseradish peroxidase (WGA-HRP), or using the disappearance of fluoride resistant acid phosphatase (FRAP) after nerve section. The projection patterns in lamina II were similar following the two procedures. The median and the radial nerve fibers projected to the medial and the intermediate thirds, respectively, of the dorsal horn lamina II in spinal cord segments C4-C8. The ulnar nerve projected to segments C6-C8 between the areas occupied by the other two nerves. The FRAP method also showed that the lateral part of lamina II, which was not filled by radial nerve fibers, received the projections from the dorsal cutaneous branches of cervical spinal nerves. In addition, FRAP disappeared from the medial end of segment T1 after skin incisions extending from the medial brachium to the axilla, which seemed due to severance of the cutaneous branchlets of the lateral anterior thoracic nerve. The FRAP procedure is thus sensitive enough to detect fibers in lamina II arising from small peripheral nerves, and may be used as an alternative to the anterograde tracing methods whenever there are no overlapping projections.

  16. Unresponsive afferent nerve fibres in the sural nerve of the rat.

    PubMed Central

    Handwerker, H O; Kilo, S; Reeh, P W

    1991-01-01

    1. The proportion of primary afferent nerve fibres in a skin nerve of the rat that responded or failed to respond to mechanical or thermal stimulation of the skin in the noxious and non-noxious range was analysed. 2. Activity of afferent nerve fibres was recorded from the dorsal roots. Units projecting into the sural nerve were selected using supramaximal electrical stimulation of the nerve stem. All other hindleg nerves were cut. 3. The receptive fields were searched by carefully examining the hindleg skin with noxious and innocuous mechanical, cooling and warming stimuli. Probing of the intrinsic foot muscles and manipulation of the ankle and toe joints was employed to recruit units projecting to deeper tissues. 4. In a first series of twenty-two experiments, eighty-nine rapidly conducting myelinated A beta units, thirty slowly conducting myelinated A delta units and 101 unmyelinated C units were investigated. Most units were identified as belonging to one of the established classes of cutaneous sensory units and this was also ascertained by a collision test. 5. Two A beta, eight A delta and forty-six C fibres did not respond to any one of the stimuli. Electrical thresholds and conduction velocities of the unresponsive C fibres were not significantly different from those of the units responding to natural stimulation of their receptive fields. In the A delta group unresponsive and high threshold mechanoreceptive units were preferentially found among the units with the slowest conduction velocities. 6. In a second series of seven experiments, one single nerve filament containing responsive and unresponsive C fibres was tested repetitively at 30 min intervals. Twenty unresponsive units and seven units responding to noxious mechanical and/or heat stimuli were studied. Ten of the twenty initially unresponsive units became activated by mechanical and/or heat stimuli after observation times of 30-150 min. Some of these units had mechanical thresholds as low as 64 m

  17. Pre-differentiation of mesenchymal stromal cells in combination with a microstructured nerve guide supports peripheral nerve regeneration in the rat sciatic nerve model.

    PubMed

    Boecker, Arne Hendrik; van Neerven, Sabien Geraldine Antonia; Scheffel, Juliane; Tank, Julian; Altinova, Haktan; Seidensticker, Katrin; Deumens, Ronald; Tolba, Rene; Weis, Joachim; Brook, Gary Anthony; Pallua, Norbert; Bozkurt, Ahmet

    2016-02-01

    Many bioartificial nerve guides have been investigated pre-clinically for their nerve regeneration-supporting function, often in comparison to autologous nerve transplantation, which is still regarded as the current clinical gold standard. Enrichment of these scaffolds with cells intended to support axonal regeneration has been explored as a strategy to boost axonal regeneration across these nerve guides Ansselin et al. (1998). In the present study, 20 mm rat sciatic nerve defects were implanted with a cell-seeded microstructured collagen nerve guide (Perimaix) or an autologous nerve graft. Under the influence of seeded, pre-differentiated mesenchymal stromal cells, axons regenerated well into the Perimaix nerve guide. Myelination-related parameters, like myelin sheath thickness, benefitted from an additional seeding with pre-differentiated mesenchymal stromal cells. Furthermore, both the number of retrogradely labelled sensory neurons and the axon density within the implant were elevated in the cell-seeded scaffold group with pre-differentiated mesenchymal stromal cells. However, a pre-differentiation had no influence on functional recovery. An additional cell seeding of the Perimaix nerve guide with mesenchymal stromal cells led to an extent of functional recovery, independent of the differentiation status, similar to autologous nerve transplantation. These findings encourage further investigations on pre-differentiated mesenchymal stromal cells as a cellular support for peripheral nerve regeneration.

  18. Effect of vagus nerve stimulation on thermal injury in rats.

    PubMed

    Song, Xue-Min; Li, Jian-Guo; Wang, Yan-Lin; Liang, Hui; Huang, Yue; Yuan, Xiang; Zhou, Qing; Zhang, Zong-Ze

    2010-02-01

    To investigate the effects of vagus nerve stimulation on haemodynamics, pulmonary histopathology, arterial blood gas and pro-inflammatory responses to thermal injury. Forty-eight male Sprague-Dawley (SD) rats were randomly divided into six equal groups: normal control (NC) group; thermal injury (TEM) group subjected to 40% total body surface area (%TBSA) third-degree thermal injury; vagotomy (VGX) group subjected to bilateral cervical vagotomy after thermal injury; electrical stimulation (STM) group subjected to bilateral cervical vagotomy plus the left vagus nerve trunk electrical stimulation (5 V, 2 ms and 1 Hz) after thermal injury; the antagonist of muscarinic acetylcholine receptor (MRA) group administrated with atropine (0.1 mg kg(-1)) before electrical stimulation and the antagonist of nicotinic acetylcholine receptor (NRA) group administrated with hexamethonium (10 mg kg(-1)) before electrical stimulation. The haemodynamics, histopathology of lung tissue, arterial blood gas, lactic acid, tumour necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) levels were measured. Vagus nerve electrical stimulation not only significantly increased the mean arterial pressure (MAP) and heart rate (HR), but also decreased the infiltration of inflammatory cells into interstitial and alveolar spaces after thermal challenge and attenuated TNF-alpha and IL-6 production. Hexamethonium pre-treatment significantly reversed the effects of vagal electrical stimulation, but atropine administration before electrical stimulation had no such effects. Direct electrical stimulation of the vagus nerve might produce therapeutic effect on thermal injury. The effect may be realised by limiting the inflammatory response via nicotinic acetylcholine receptors in rats. Copyright (c) 2009 Elsevier Ltd and ISBI. All rights reserved.

  19. The central projections of the laryngeal nerves in the rat.

    PubMed

    Pascual-Font, Arán; Hernández-Morato, Ignacio; McHanwell, Stephen; Vázquez, Teresa; Maranillo, Eva; Sañudo, Jose; Valderrama-Canales, Francisco J

    2011-08-01

    The larynx serves respiratory, protective, and phonatory functions. The motor and sensory innervation to the larynx controlling these functions is provided by the superior laryngeal nerve (SLN) and the recurrent laryngeal nerve (RLN). Classical studies state that the SLN innervates the cricothyroid muscle and provides sensory innervation to the supraglottic cavity, whereas the RLN supplies motor innervation to the remaining intrinsic laryngeal muscles and sensory innervation to the infraglottic cavity, but recent data suggest a more complex anatomical and functional organisation. The current neuroanatomical tracing study was undertaken to provide a comprehensive description of the central brainstem connections of the axons within the SLN and the RLN, including those neurons that innervate the larynx. The study has been carried out in 41 adult male Sprague-Dawley rats. The central projections of the laryngeal nerves were labelled following application of biotinylated dextran amines onto the SLN, the RLN or both. The most remarkable result of the study is that in the rat the RLN does not contain any afferent axons from the larynx, in contrast to the pattern observed in many other species including man. The RLN supplied only special visceromotor innervation to the intrinsic muscles of the larynx from motoneurons in the nucleus ambiguus (Amb). All the afferent axons innervating the larynx are contained within the SLN, and reach the nucleus of the solitary tract. The SLN also contained secretomotor efferents originating from motoneurons in the dorsal motor nucleus of the vagus, and special visceral efferent fibres from the Amb. In conclusion, the present study shows that in the rat the innervation of the larynx differs in significant ways from that described in other species. © 2011 The Authors. Journal of Anatomy © 2011 Anatomical Society of Great Britain and Ireland.

  20. The central projections of the laryngeal nerves in the rat

    PubMed Central

    Pascual-Font, Arán; Hernández-Morato, Ignacio; McHanwell, Stephen; Vázquez, Teresa; Maranillo, Eva; Sañudo, Jose; Valderrama-Canales, Francisco J

    2011-01-01

    The larynx serves respiratory, protective, and phonatory functions. The motor and sensory innervation to the larynx controlling these functions is provided by the superior laryngeal nerve (SLN) and the recurrent laryngeal nerve (RLN). Classical studies state that the SLN innervates the cricothyroid muscle and provides sensory innervation to the supraglottic cavity, whereas the RLN supplies motor innervation to the remaining intrinsic laryngeal muscles and sensory innervation to the infraglottic cavity, but recent data suggest a more complex anatomical and functional organisation. The current neuroanatomical tracing study was undertaken to provide a comprehensive description of the central brainstem connections of the axons within the SLN and the RLN, including those neurons that innervate the larynx. The study has been carried out in 41 adult male Sprague–Dawley rats. The central projections of the laryngeal nerves were labelled following application of biotinylated dextran amines onto the SLN, the RLN or both. The most remarkable result of the study is that in the rat the RLN does not contain any afferent axons from the larynx, in contrast to the pattern observed in many other species including man. The RLN supplied only special visceromotor innervation to the intrinsic muscles of the larynx from motoneurons in the nucleus ambiguus (Amb). All the afferent axons innervating the larynx are contained within the SLN, and reach the nucleus of the solitary tract. The SLN also contained secretomotor efferents originating from motoneurons in the dorsal motor nucleus of the vagus, and special visceral efferent fibres from the Amb. In conclusion, the present study shows that in the rat the innervation of the larynx differs in significant ways from that described in other species. PMID:21599662

  1. 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.

  2. Tongue muscle plasticity following hypoglossal nerve stimulation in aged rats

    PubMed Central

    Connor, Nadine P.; Russell, John A.; Jackson, Michelle A.; Kletzien, Heidi; Wang, Hao; Schaser, Allison J.; Leverson, Glen E.; Zealear, David L.

    2012-01-01

    Introduction Age-related decreases in tongue muscle mass and strength have been reported. It may be possible to prevent age-related tongue muscle changes using neuromuscular electrical stimulation (NMES). Our hypothesis was that alterations in muscle contractile properties and myosin heavy chain composition would be found following NMES. Methods Fifty-four young, middle-aged and old Fischer 344/Brown Norway rats were included. Twenty-four rats underwent bilateral electrical stimulation of the hypoglossal nerves for 8 weeks and were compared with control or sham rats. Muscle contractile properties and myosin heavy chain (MHC) in the genioglossus (GG), styloglossus (SG) and hyoglossus (HG) muscles were examined. Results In comparison with unstimulated control rats, we found reduced muscle fatigue, increased contraction and half decay times and increased twitch and tetanic tension. Increased Type I MHC was found, except for GG in old and middle-aged rats. Discussion Transitions in tongue muscle contractile properties and phenotype were found following NMES. PMID:23169566

  3. Ex vivo peripheral nerve detection of rats by spontaneous Raman spectroscopy

    PubMed Central

    Minamikawa, Takeo; Harada, Yoshinori; Takamatsu, Tetsuro

    2015-01-01

    Nerve-sparing surgery is increasingly being applied to avoid functional deficits of the limbs and organs following surgery. Peripheral nerves that should be preserved are, however, sometimes misidentified due to similarity of shape and color to non-nerve tissues. To avoid misidentification of peripheral nerves, development of an in situ nerve detection method is desired. In this study, we report the label-free detection of ex vivo peripheral nerves of Wistar rats by using Raman spectroscopy. We obtained Raman spectra of peripheral nerves (myelinated and unmyelinated nerves) and their adjacent tissues of Wistar rats without any treatment such as fixation and/or staining. For the identification of tissue species and further analysis of spectral features, we proposed a principal component regression-based discriminant analysis with representative Raman spectra of peripheral nerves and their adjacent tissues. Our prediction model selectively detected myelinated nerves and unmyelinated nerves of Wistar rats with respective sensitivities of 95.5% and 88.3% and specificities of 99.4% and 93.5%. Furthermore, important spectral features for the identification of tissue species were revealed by detailed analysis of principal components of representative Raman spectra of tissues. Our proposed approach may provide a unique and powerful tool for peripheral nerve detection for nerve-sparing surgery in the future. PMID:26602842

  4. Far-Infrared Therapy Promotes Nerve Repair following End-to-End Neurorrhaphy in Rat Models of Sciatic Nerve Injury

    PubMed Central

    Chen, Tai-Yuan; Yang, Yi-Chin; Sha, Ya-Na; Chou, Jiun-Rou

    2015-01-01

    This study employed a rat model of sciatic nerve injury to investigate the effects of postoperative low-power far-infrared (FIR) radiation therapy on nerve repair following end-to-end neurorrhaphy. The rat models were divided into the following 3 groups: (1) nerve injury without FIR biostimulation (NI/sham group); (2) nerve injury with FIR biostimulation (NI/FIR group); and (3) noninjured controls (normal group). Walking-track analysis results showed that the NI/FIR group exhibited significantly higher sciatic functional indices at 8 weeks after surgery (P < 0.05) compared with the NI/sham group. The decreased expression of CD4 and CD8 in the NI/FIR group indicated that FIR irradiation modulated the inflammatory process during recovery. Compared with the NI/sham group, the NI/FIR group exhibited a significant reduction in muscle atrophy (P < 0.05). Furthermore, histomorphometric assessment indicated that the nerves regenerated more rapidly in the NI/FIR group than in the NI/sham group; furthermore, the NI/FIR group regenerated neural tissue over a larger area, as well as nerve fibers of greater diameter and with thicker myelin sheaths. Functional recovery, inflammatory response, muscular reinnervation, and histomorphometric assessment all indicated that FIR radiation therapy can accelerate nerve repair following end-to-end neurorrhaphy of the sciatic nerve. PMID:25722734

  5. L-carnitine alleviates sciatic nerve crush injury in rats: functional and electron microscopy assessments

    PubMed Central

    Avsar, Ümmü Zeynep; Avsar, Umit; Aydin, Ali; Yayla, Muhammed; Ozturkkaragoz, Berna; Un, Harun; Saritemur, Murat; Mercantepe, Tolga

    2014-01-01

    Several studies have demonstrated that L-carnitine exhibits neuroprotective effects on injured sciatic nerve of rats with diabetes mellitus. It is hypothesized that L-carnitine exhibits neuroprotective effects on injured sciatic nerve of rats. Rat sciatic nerve was crush injured by a forceps and exhibited degenerative changes. After intragastric administration of 50 and 100 mg/kg L-carnitine for 30 days, axon area, myelin sheath area, axon diameter, myelin sheath diameter, and numerical density of the myelinated axons of injured sciatic nerve were similar to normal, and the function of injured sciatic nerve also improved significantly. These findings suggest that L-carnitine exhibits neuroprotective effects on sciatic nerve crush injury in rats. PMID:25206754

  6. Intraneural perineurioma of unilateral radial and median nerves manifesting with long-standing focal amyotrophy in a 14-year-old-boy.

    PubMed

    Nagappa, Madhu; Chickabasaviah, Yasha T; Bharath, Rose D; Bindu, Parayil S; Sinha, Sanjib; Taly, Arun B

    2013-12-01

    Intraneural perineuriomas are rare tumors of the peripheral nerves with unique immunohistochemical findings. In this report, we highlight the clinical and imaging findings of an adolescent male with histologically proven intraneural perineurioma involving multiple nerves. The salient features included a clinically progressive course, imaging evidence of involvement of long segments of multiple nerves, enlargement of individual fascicles within the affected nerves, and intense contrast enhancement of the enlarged fascicles. The identification of enlarged fascicles with intense contrast enhancement within the affected and distended nerve segments may aid in distinguishing intraneural perineurioma from other tumors affecting the peripheral nerves.

  7. A nanofibrous PHBV tube with Schwann cell as artificial nerve graft contributing to rat sciatic nerve regeneration across a 30-mm defect bridge.

    PubMed

    Biazar, Esmaeil; Heidari Keshel, Saeed

    2013-02-01

    A nanofibrous PHBV nerve conduit has been used to evaluate its efficiency based on the promotion of nerve regeneration in rats. The designed conduits were investigated by physical, mechanical and microscopic analyses. The conduits were implanted into a 30-mm gap in the sciatic nerves of the rats. Four months after surgery, the regenerated nerves were evaluated by macroscopic assessments and histology. This polymeric conduit had sufficiently high mechanical properties to serve as a nerve guide. The results demonstrated that in the nanofibrous graft with cells, the sciatic nerve trunk had been reconstructed with restoration of nerve continuity and formatted nerve fibers with myelination. For the grafts especially the nanofibrous conduits with cells, muscle cells of gastrocnemius on the operated side were uniform in their size and structures. This study proves the feasibility of artificial conduit with Schwann cells for nerve regeneration by bridging a longer defect in a rat model.

  8. Neurokinin 3 Receptor-Expressing Neurons in the Median Preoptic Nucleus Modulate Heat-Dissipation Effectors in the Female Rat

    PubMed Central

    Mittelman-Smith, Melinda A.; Krajewski-Hall, Sally J.; McMullen, Nathaniel T.

    2015-01-01

    KNDy neurons facilitate tail skin vasodilation and modulate the effects of estradiol on thermoregulation. We hypothesize that KNDy neurons influence cutaneous vasodilation via projections to neurons in the median preoptic nucleus (MnPO) that express the neurokinin 3 receptor (NK3R). In support of this hypothesis, focal microinjections of senktide, an NK3R agonist, into the MnPO lowers core temperature (TCORE) in the female rat. To further study the role of MnPO NK3R neurons in thermoregulation, these neurons were specifically ablated using a conjugate of a selective NK3R agonist and saporin (NK3-SAP). NK3-SAP or blank-SAP (control) was injected into the MnPO/medial septum. Tail skin temperature (TSKIN) and TCORE were measured in ovariectomized rats exposed to 3 ambient temperatures (TAMBIENT) before and after estradiol-17β (E2) treatment. Before killing, we injected senktide (sc), monitored TCORE for 70 minutes, and harvested brains for Fos immunohistochemistry. Ablation of MnPO NK3R neurons lowered TSKIN at neutral and subneutral TAMBIENT regardless of E2 treatment. However, ablation did not prevent the effects of E2 on TCORE and TSKIN. In control rats, senktide injections induced hypothermia with numerous Fos-immunoreactive cells in the MnPO. In contrast, in NK3-SAP rats, senktide did not alter TCORE and minimal Fos-immunoreactive neurons were identified in the MnPO. These data show that NK3R neurons in the MnPO are required for the hypothermic effects of senktide but not for the E2 modulation of thermoregulation. The lower TSKIN in NK3-SAP–injected rats suggests that MnPO NK3R neurons, like KNDy neurons, facilitate cutaneous vasodilation, an important heat-dissipation effector. PMID:25825817

  9. Hypoglycemia enhances turnover of corticotropin-releasing factor and of vasopressin in the zona externa of the rat median eminence.

    PubMed

    Berkenbosch, F; De Goeij, D C; Tilders, F J

    1989-07-01

    Insulin administration to overnight fasted rats causes a dose-dependent decline in plasma glucose concentrations and a dose-dependent increase in plasma ACTH concentrations. The ACTH response, but not the glucose response, was blocked by treatment with chlorpromazine-morphine-pentobarbital, indicating that the main factors triggering the ACTH response are of central, rather than peripheral, origin. To study whether insulin affected the turnover of CRF and vasopressin (AVP) in the zona externa of the median eminence (ZEME), we determined the rate of decline of both hypophysiotropic factors in rats with or without blockade of axonal transport by colchicine. In the ZEME, the concentrations of CRF and AVP were assessed by quantitative immunocytochemistry (QICC) in tissue sections or by RIA in median eminence extracts. QICC allows selective quantification of AVP and other peptides within the ZEME. The changes in the CRF content, as measured by QICC and RIA, were linearly correlated (r = 0.99), demonstrating that changes in peptide-staining intensity reflect changes in peptide content. Colchicine, when given intracisternally in a nontoxic dose of 5 micrograms, had no marked effect on resting plasma levels of ACTH and only slightly reduced the ACTH response to insulin-induced hypoglycemia. In the ZEME, CRF and AVP concentrations at rest were not affected by colchicine. In colchicine-treated rats insulin-induced hypoglycemia resulted in a prominent decline in CRF and AVP concentrations in the ZEME. The CRF concentration declined at a rate of 23%/h over a period of 3 h. The AVP concentration declined to a similar extent as CRF over the first hour, but tended to fall at the later time points. We conclude that hypoglycemia increases turnover of both CRF and AVP in the ZEME. However, the turnover rates of both hypophysiotropic peptides do not appear to be quantitatively coupled.

  10. The relevance of the corticographic median nerve somatosensory evoked potentials (SEPs) phase reversal in the surgical treatment of brain tumors in central cortex.

    PubMed

    Tomás, R; Haninec, P; Houstava, L

    2006-01-01

    Tumors of the central brain cortex change the original anatomy of this important area and so an intraoperative localization of the perirolandic structures is crucial in decision concerning the way and the extent of tumor resection. The phase reversal of median nerve SEPs is an essential tool for neurosurgical procedures in and around the perirolandic gyri. This study examines the relevance of the method in a group of 62 patients having surgery of tumors in and around the central region. A success rate in obtaining the SEP phase reversal was 94%. In all groups of patients the complete resection of tumor was achieved in 58% , subtotal resection in 19% and partial or biopsy only in 23%. The long term impairment of neurological status was observed in 6% of patients. Compared to the recently published studies our results are acceptable both in completeness of tumor resection and relatively low ratio of impaired postoperative neurological deficit despite the fact, that in the majority of patients the phase reversal mapping was the only method guiding the surgical procedure. Our study supports the crucial role of the central cortex mapping using the SEP phase reversal method in the surgery for the tumors of the primary sensorimotor cortex.

  11. Selection of the donor nerve for end-to-side neurorrhaphy.

    PubMed

    Papalia, Igor; Cardaci, Aurelio; d'Alcontres, Francesco Stagno; Lee, Jennifer M; Tos, Pierluigi; Geuna, Stefano

    2007-08-01

    The authors of other studies have reported that the selection of an agonistic donor nerve is required for recovering voluntary motor control after end-to-side nerve repair. In this experimental investigation, the authors' goal was to verify this assumption by performing end-to-side neurorrhaphy of the rat median nerve on its antagonistic radial nerve. The left median nerve in 10 adult female rats was repaired by end-to-side neurorrhaphy after epineuriotomy on the radial nerve at the middle of the brachium. The time course of median nerve functional recovery was then assessed using the grasping test until postoperative Week 30. Before removing the nerve, the surgical site was carefully explored to exclude contamination by the proximal nerve stump, and the functional anatomy of median and radial nerves was assessed by electrical stimulation. Repaired nerves were then processed for resin embedding, and semithin sections were obtained for nerve fiber histomorphometry by using the dissector method. Repaired median nerves were repopulated by nerve fibers regenerating from the radial donor nerve as previously shown. Moreover, voluntary motor control of the flexor muscles innervated by the median nerve was progressively recovered beginning in postoperative Week 10 and reaching 42% of normal by Week 30. Contrary to previously reported data, recovery of voluntary motor function after end-to-side nerve repair can also be expected when an antagonistic nerve is used as a donor nerve.

  12. Palmitoylethanolamide inhibits glutamate release in rat cerebrocortical nerve terminals.

    PubMed

    Lin, Tzu-Yu; Lu, Cheng-Wei; Wu, Chia-Chan; Huang, Shu-Kuei; Wang, Su-Jane

    2015-03-11

    The effect of palmitoylethanolamide (PEA), an endogenous fatty acid amide displaying neuroprotective actions, on glutamate release from rat cerebrocortical nerve terminals (synaptosomes) was investigated. PEA inhibited the Ca²⁺-dependent release of glutamate, which was triggered by exposing synaptosomes to the potassium channel blocker 4-aminopyridine. This release inhibition was concentration dependent, associated with a reduction in cytosolic Ca²⁺ concentration, and not due to a change in synaptosomal membrane potential. The glutamate release-inhibiting effect of PEA was prevented by the Ca(v)2.1 (P/Q-type) channel blocker ω-agatoxin IVA or the protein kinase A inhibitor H89, not affected by the intracellular Ca²⁺ release inhibitors dantrolene and CGP37157, and partially antagonized by the cannabinoid CB1 receptor antagonist AM281. Based on these results, we suggest that PEA exerts its presynaptic inhibition, likely through a reduction in the Ca²⁺ influx mediated by Ca(v)2.1 (P/Q-type) channels, thereby inhibiting the release of glutamate from rat cortical nerve terminals. This release inhibition might be linked to the activation of presynaptic cannabinoid CB1 receptors and the suppression of the protein kinase A pathway.

  13. Dexamethasone enhanced functional recovery after sciatic nerve crush injury in rats.

    PubMed

    Feng, Xinhong; Yuan, Wei

    2015-01-01

    Dexamethasone is currently used for the treatment of peripheral nerve injury, but its mechanisms of action are not completely understood. Inflammation/immune response at the site of nerve lesion is known to be an essential trigger of the pathological changes that have a critical impact on nerve repair and regeneration. In this study, we observed the effects of various doses of dexamethasone on the functional recovery after sciatic nerve crush injury in a rat model. Motor functional recovery was monitored by walking track analysis and gastrocnemius muscle mass ratio. The myelinated axon number was counted by morphometric analysis. Rats administered dexamethasone by local intramuscular injection had a higher nerve function index value, increased gastrocnemius muscle mass ratio, reduced Wallerian degeneration severity, and enhanced regenerated myelinated nerve fibers. Immunohistochemical analysis was performed for CD3 expression, which is a marker for T-cell activation, and infiltration in the sciatic nerve. Dexamethasone-injected rats had fewer CD3-positive cells compared to controls. Furthermore, we found increased expression of GAP-43, which is a factor associated with development and plasticity of the nervous system, in rat nerves receiving dexamethasone. These results provide strong evidence that dexamethasone enhances sciatic nerve regeneration and function recovery in a rat model of sciatic nerve injury through immunosuppressive and potential neurotrophic effects.

  14. Regenerative effect of adipose tissue-derived stem cells transplantation using nerve conduit therapy on sciatic nerve injury in rats.

    PubMed

    Liu, Bai-Shuan; Yang, Yi-Chin; Shen, Chiung-Chyi

    2014-05-01

    This study proposed a biodegradable GGT nerve conduit containing genipin crosslinked gelatin annexed with tricalcium phosphate (TCP) ceramic particles for the regeneration of peripheral nerves. Cytotoxicity tests revealed that GGT-extracts were non-toxic and promoted proliferation and neuronal differentiation in the induction of stem cells (i-ASCs) derived from adipose tissue. Furthermore, the study confirmed the effectiveness of a GGT/i-ASCs nerve conduit as a guidance channel in the repair of a 10-mm gap in the sciatic nerve of rats. At eight weeks post-implantation, walking track analysis showed a significantly higher sciatic function index (SFI) (P < 0.05) in the GGT/i-ASC group than in the autograft group. Furthermore, the mean recovery index of compound muscle action potential (CMAP) differed significantly between GGT/i-ASCs and autograft groups (P < 0.05), both of which were significantly superior to the GGT group (P < 0.05). No severe inflammatory reaction in the peripheral nerve tissue at the site of implantation was observed in either group. Histological observation and immunohistochemistry revealed that the morphology and distribution patterns of nerve fibers in the GGT/i-ASCs nerve conduits were similar to those of the autografts. These promising results achieved through a combination of regenerative cells and GGT nerve conduits suggest the potential value in the future development of clinical applications for the treatment of peripheral nerve injury.

  15. Chitosan-cross-linked nanofibrous PHBV nerve guide for rat sciatic nerve regeneration across a defect bridge.

    PubMed

    Biazar, Esmaeil; Keshel, Saeed Heidari

    2013-01-01

    The aim of this study was to produce a chitosan-cross-linked nanofibrous biodegradable poly (3-hydroxybutyrate-co-3-hydroxyvalerate) nerve conduit. The artificial nerve scaffold designed by electrospinning method and cross-linked with chitosan by chemical method. Afterwards, the scaffolds were evaluated by microscopic, physical, and mechanical analyses and cell culture assays with Schwann cells. The conduits were implanted into a 10 mm gap in the sciatic nerves of the rats. Four months after surgery, the regenerated nerves were evaluated by macroscopic assessments and histology. This polymeric conduit had sufficiently good mechanical properties to serve as a nerve guide. Cellular experiments showed a better cell adhesion, growth, and proliferation inside the cross-linked nanofibrous scaffolds compared with un-cross-linked ones, also Schwann cells well attached on chitosan-cross-linked nanofibrous surface. The in vivo results demonstrated that in the nanofibrous graft, the sciatic nerve trunk had been reconstructed with restoration of nerve continuity and formatted nerve fibers with myelination. This neural conduit appears to have the right organization for testing in vivo nerve tissue engineering studies.

  16. Effects of pudendal nerve injury in the female rat.

    PubMed

    Kerns, J M; Damaser, M S; Kane, J M; Sakamoto, K; Benson, J T; Shott, S; Brubaker, L

    2000-01-01

    To test a neurogenic hypothesis for external urethral sphincter (EUS) dysfunction associated with urinary incontinence, the proximal pudendal nerve was crushed in anesthetized retired breeder female rats (n = 5) and compared with a sham lesion group (n = 4). Outcome measures included concentric needle electromyograms (EMGs) from the target EUS, voiding patterns during a 2-hour dark period, and micturition data over a 24-hour period. Fast Blue (FB) was introduced to the crush site at the time of injury and Diamidino Yellow (DY) to the EUS at the time the rats were killed (3 months post-operative), when histological analysis of the nerve and urethra was also performed. EMG records indicated the EUS motor units undergo typical denervation changes followed by regeneration and recovery. Voiding patterns from the crush group show a significant increase of small urine marks in the front third of the cage. At 1-2 weeks post-op, the frequency of voids was significantly increased in the crush group compared to pre-op and late post-op time periods. The mean volume voided in the light phase at the early post-op time was significantly increased in the sham group. Light and electron microscopic patterns seen in nerve and muscle suggest the regenerating motor units maintain a structural integrity. Motoneurons in the lower lumbar cord were labeled with either DY (14. 5 +/- 6.8), FB (31.7 +/- 23.7), or both (35.0 +/- 17.5) tracers, indicating approximately 54% of the crushed pudendal neurons regenerated to the EUS. In conclusion, several measures suggest this reversible crush lesion induces mild urinary incontinence. This animal model is promising for further development of hypotheses regarding neural injury, the pathogenesis of incontinence, and strategies aimed at prevention and treatment. Neurourol. Urodynam. 19:53-69, 2000. Copyright 2000 Wiley-Liss, Inc.

  17. Segmental origins of cardiac sympathetic nerve activity in rats.

    PubMed

    Pracejus, Natasha H; Farmer, David G S; McAllen, Robin M

    2015-01-01

    The segmental origins of cardiac sympathetic nerve activity (CSNA) were investigated in 8 urethane-anesthetized, artificially ventilated rats. The left upper thoracic sympathetic chain was exposed retropleurally after removing the heads of the second to fourth ribs. The preganglionic inputs to the chain from segments T1-T3 and the trunk distal to T3 were marked for later sectioning. CSNA was recorded conventionally, amplified, rectified and smoothed. Its mean level was quantified before and after each preganglionic input was cut, usually in rostro-caudal sequence. The level after all inputs were cut (i.e. noise and residual ECG pickup) was subtracted from previous measurements. The signal decrement from cutting each preganglionic input was then calculated as a percentage. CSNA in all rats depended on preganglionic drive from two or more segments, which were not always contiguous. Over the population, most preganglionic drive came from T3 and below, while the least came from T1. But there was striking inter-individual variation, such that the strongest drive to CSNA in any one rat could come from T1, T2, T3, or below T3. These findings provide new functional data on the segmental origins of CSNA in rats.

  18. Lentiviral-mediated transfer of CDNF promotes nerve regeneration and functional recovery after sciatic nerve injury in adult rats

    SciTech Connect

    Cheng, Lei; Liu, Yi; Zhao, Hua; Zhang, Wen; Guo, Ying-Jun; Nie, Lin

    2013-10-18

    Highlights: •CDNF was successfully transfected by a lentiviral vector into the distal sciatic nerve. •CDNF improved S-100, NF200 expression and nerve regeneration after sciatic injury. •CDNF improved the remyelination and thickness of the regenerated sciatic nerve. •CDNF improved gastrocnemius muscle weight and sciatic functional recovery. -- Abstract: Peripheral nerve injury is often followed by incomplete and unsatisfactory functional recovery and may be associated with sensory and motor impairment of the affected limb. Therefore, a novel method is needed to improve the speed of recovery and the final functional outcome after peripheral nerve injuries. This report investigates the effect of lentiviral-mediated transfer of conserved dopamine neurotrophic factor (CDNF) on regeneration of the rat peripheral nerve in a transection model in vivo. We observed notable overexpression of CDNF protein in the distal sciatic nerve after recombinant CDNF lentiviral vector application. We evaluated sciatic nerve regeneration after surgery using light and electron microscopy and the functional recovery using the sciatic functional index and target muscle weight. HE staining revealed better ordered structured in the CDNF-treated group at 8 weeks post-surgery. Quantitative analysis of immunohistochemistry of NF200 and S-100 in the CDNF group revealed significant improvement of axonal and Schwann cell regeneration compared with the control groups at 4 weeks and 8 weeks after injury. The thickness of the myelination around the axons in the CDNF group was significantly higher than in the control groups at 8 weeks post-surgery. The CDNF group displayed higher muscle weights and significantly increased sciatic nerve index values. Our findings suggest that CDNF gene therapy could provide durable and stable CDNF protein concentration and has the potential to enhance peripheral nerve regeneration, morphological and functional recovery following nerve injury, which suggests a

  19. Beneficial Effect of Metformin on Nerve Regeneration and Functional Recovery After Sciatic Nerve Crush Injury in Diabetic Rats.

    PubMed

    Ma, Junxiong; Liu, Jun; Yu, Hailong; Chen, Yu; Wang, Qi; Xiang, Liangbi

    2016-05-01

    Neuroprotective effects of metformin have been increasingly recognized in both diabetic and non-diabetic conditions. Thus far, no information has been available on the potential beneficial effects of metformin on peripheral nerve regeneration in diabetes mellitus. The present study was designed to investigate such a possibility. Diabetes was established by a single injection of streptozotocin at 50 mg/kg in rats. After sciatic nerve crush injury, the diabetic rats were intraperitoneally administrated daily for 4 weeks with metformin (30, 200 and 500 mg/kg), or normal saline, respectively. The axonal regeneration was investigated by morphometric analysis and retrograde labeling. The functional recovery was evaluated by electrophysiological studies and behavioral analysis. It was found that metformin significantly enhanced axonal regeneration and functional recovery compared to saline after sciatic nerve injury in diabetic rats. In addition, metformin at 200 and 500 mg/kg showed better performance than that at 30 mg/kg. Taken together, metformin is capable of promoting nerve regeneration after sciatic nerve injuries in diabetes mellitus, highlighting its therapeutic values for peripheral nerve injury repair in diabetes mellitus.

  20. Intrathecal administration of nerve growth factor delays GAP 43 expression and early phase regeneration of adult rat peripheral nerve.

    PubMed

    Hirata, Akira; Masaki, Toshihiro; Motoyoshi, Kazuo; Kamakura, Keiko

    2002-07-19

    Whether nerve growth factor (NGF) promotes peripheral nerve regeneration in vivo, in particular in adults, is controversial. We therefore examined the effect of exogenous NGF on nerve regeneration and the expression of GAP 43 (growth-associated protein 43) in adult rats. NGF was infused intrathecally via an osmotic mini-pump, while control rats received artificial cerebrospinal fluid. Two days after the infusion was initiated, the right sciatic nerves were transected or crushed, and the animals allowed to survive for 3 to 11 days. The right DRG, the right proximal stump of the transected sciatic nerve, and the posterior horn of the spinal cord were examined by Western blotting, immunohistochemistry, and electron microscopy. GAP 43 immunoreactivity in the NGF-treated animals was significantly lower than in the aCSF-treated controls. Electron microscopy showed that the number of myelinated and unmyelinated axons decreased significantly in the NGF-treated rats as compared with the controls. These findings are indicative that exogenous NGF delayed GAP 43 induction and the early phase of peripheral nerve regeneration and supports the hypothesis that the loss of NGF supply from peripheral targets via retrograde transport caused by axotomy serves as a signal for DRG neurons to invoke regenerative responses. NGF administered intrathecally may delay the neurons' perception of the reduction of the endogenous NGF, causing a delay in conversion of DRG neurons from the normal physiological condition to regrowth state.

  1. 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

  2. Rapid-rate paired associative stimulation of the median nerve and motor cortex can produce long-lasting changes in motor cortical excitability in humans

    PubMed Central

    Quartarone, Angelo; Rizzo, Vincenzo; Bagnato, Sergio; Morgante, Francesca; Sant'Angelo, Antonino; Girlanda, Paolo; Roman Siebner, Hartwig

    2006-01-01

    Repetitive transcranial magnetic stimulation (rTMS) or repetitive electrical peripheral nerve stimulation (rENS) can induce changes in the excitability of the human motor cortex (M1) that is often short-lasting and variable, and occurs only after prolonged periods of stimulation. In 10 healthy volunteers, we used a new repetitive paired associative stimulation (rPAS) protocol to facilitate and prolong the effects of rENS and rTMS on cortical excitability. Sub-motor threshold 5 Hz rENS of the right median nerve was synchronized with submotor threshold 5 Hz rTMS of the left M1 at a constant interval for 2 min. The interstimulus interval (ISI) between the peripheral stimulus and the transcranial stimulation was set at 10 ms (5 Hz rPAS10ms) or 25 ms (5 Hz rPAS25ms). TMS was given over the hot spot of the right abductor pollicis brevis (APB) muscle. Before and after rPAS, we measured the amplitude of the unconditioned motor evoked potential (MEP), intracortical inhibition (ICI) and facilitation (ICF), short- and long-latency afferent inhibition (SAI and LAI) in the conditioned M1. The 5 Hz rPAS25ms protocol but not the 5 Hz rPAS10ms protocol caused a somatotopically specific increase in mean MEP amplitudes in the relaxed APB muscle. The 5 Hz rPAS25ms protocol also led to a loss of SAI, but there was no correlation between individual changes in SAI and corticospinal excitability. These after-effects were still present 6 h after 5 Hz rPAS25ms. There was no consistent effect on ICI, ICF and LAI. The 5 Hz rENS and 5 Hz rTMS protocols failed to induce any change in corticospinal excitability when given alone. These findings show that 2 min of 5 Hz rPAS25ms produce a long-lasting and somatotopically specific increase in corticospinal excitability, presumably by sensorimotor disinhibition. PMID:16825301

  3. Nerve excitability in the rat forelimb: a technique to improve translational utility.

    PubMed

    Arnold, Ria; Moldovan, Mihai; Rosberg, Mette Romer; Krishnan, Arun V; Morris, Renee; Krarup, Christian

    2017-01-01

    Nerve excitability testing by threshold-tracking is the only available method to study axonal ion channel function and membrane potential in the clinical setting. The measures are, however, indirect and the interpretation of neuropathic changes remains challenging. The same multiple measures of axonal excitability were adapted to further explore the pathophysiological changes in rodent disease models under pharmacologic and genetic manipulations. These studies are typically limited to the investigation of the "long nerves" such as the tail or the tibial nerves. We introduce a novel setup to explore the ulnar nerve excitability in rodents. We provide normative ulnar data in 11 adult female Long Evans rats under anaesthesia by comparison with tibial and caudal nerves. Additionally, these measures were repeated weekly on 3 occasions to determine the repeatability of these tests. Nerve excitability assessment of ulnar nerve proved to be a longitudinally repeatable measure of axonal function mature in rats, as were measures in tibial and caudal nerves. Comparison with existing method: Ulnar nerve motor excitability measures were different from the caudal and tibial excitability measures. Most notably, ulnar nerve showed the largest threshold changes during both depolarizing and hyperpolarizing threshold electrotonus. Ulnar nerves demonstrate a distinct nerve excitability profile than the caudal and tibial nerves which could have functional and pathological implications. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Alcohol and nicotine administration inhibits serotonin synthesis and tryptophan hydroxylase expression in dorsal and median raphe of young rats.

    PubMed

    Jang, Mi-Hyeon; Shin, Min-Chul; Lee, Taeck-Hyun; Kim, Young-Pyo; Jung, Sae-Bin; Shin, Dong-Hoon; Kim, Hong; Kim, Sung-Soo; Kim, Ee-Hwa; Kim, Chang-Ju

    2002-08-30

    Serotonin (5-hydroxytryptamine, 5-HT) has been implicated in the pathophysiology of various neuropsychiatric disorders. In the present study, the effects of alcohol and nicotine on the synthesis of 5-HT and the expression of tryptophan hydroxylase (TPH), the rate-limiting enzyme of 5-HT synthesis, in the dorsal and median raphe of young rats were investigated via immunohistochemistry. The numbers of the 5-HT-positive and TPH-positive cells were reduced by alcohol and nicotine treatment in a dose-dependent manner. Based on the results, it can be suggested that the pathogenesis of alcohol- and nicotine-induced neuropsychological disorders involves alcohol- and nicotine-induced suppression of 5-HT synthesis and TPH expression in raphe, and that this may be of particular relevance in the consumption of alcohol and nicotine during adolescence.

  5. Involvement of the median raphe nucleus in antinociception induced by morphine, buprenorphine and tilidine in the rat.

    PubMed

    Bryant, R M; Olley, J E; Tyers, M B

    1982-12-01

    1 Antinociception induced by three analgesics with differing profiles of activity, morphine, buprenorphine and tilidine, have been evaluated in the hot plate and paw pressure tests after administration by the subcutaneous route and directly into the median raphe nucleus in the conscious rat. 2 Behavioural and neurological effects of the three analgesics were also assessed. 3 The typical profiles of antinociceptive activity induced by the three analgesics were qualitatively similar after either route of administration. Morphine induced naloxone-sensitive dose-dependent effects in both tests. Buprenorphine showed naloxone-sensitive effects with a bell-shaped dose-response curve in the thermal test but dose-dependent activity in the pressure test. Tilidine induced naloxone-sensitive dose-dependent effects in the thermal test but demonstrated naloxone-insensitive activity in the paw pressure test. 4 The behavioural and neurological effects of the analgesics in the dose range used would not have affected the animals' ability to respond to the nociceptive stimuli. 5 The results suggest that the median raphe could participate in drug-induced antinociception. The mechanisms by which this might occur are discussed.

  6. Low-intensity pulsed ultrasound treatment improved the rate of autograft peripheral nerve regeneration in rat

    PubMed Central

    Jiang, Wenli; Wang, Yuexiang; Tang, Jie; Peng, Jiang; Wang, Yu; Guo, Quanyi; Guo, Zhiyuan; Li, Pan; Xiao, Bo; Zhang, Jinxing

    2016-01-01

    Low intensity pulsed ultrasound (LIPUS) has been widely used in clinic for the treatment of repairing pseudarthrosis, bone fractures and of healing in various soft tissues. Some reports indicated that LIPUS accelerated peripheral nerve regeneration including Schwann cells (SCs) and injured nerves. But little is known about its appropriate intensities on autograft nerves. This study was to investigate which intensity of LIPUS improved the regeneration of gold standard postsurgical nerves in experimental rat model. Sprague-Dawley rats were made into 10 mm right side sciatic nerve reversed autologous nerve transplantation and randomly treated with 250 mW/cm2, 500 mW/cm2 or 750 mW/cm2 LIPUS for 2–12 weeks after operation. Functional and pathological results showed that LIPUS of 250 mW/cm2 significantly induced faster rate of axonal regeneration. This suggested that autograft nerve regeneration was improved. PMID:27102358

  7. Restoring motor control and sensory feedback in people with upper extremity amputations using arrays of 96 microelectrodes implanted in the median and ulnar nerves

    NASA Astrophysics Data System (ADS)

    Davis, T. S.; Wark, H. A. C.; Hutchinson, D. T.; Warren, D. J.; O'Neill, K.; Scheinblum, T.; Clark, G. A.; Normann, R. A.; Greger, B.

    2016-06-01

    Objective. An important goal of neuroprosthetic research is to establish bidirectional communication between the user and new prosthetic limbs that are capable of controlling >20 different movements. One strategy for achieving this goal is to interface the prosthetic limb directly with efferent and afferent fibres in the peripheral nervous system using an array of intrafascicular microelectrodes. This approach would provide access to a large number of independent neural pathways for controlling high degree-of-freedom prosthetic limbs, as well as evoking multiple-complex sensory percepts. Approach. Utah Slanted Electrode Arrays (USEAs, 96 recording/stimulating electrodes) were implanted for 30 days into the median (Subject 1-M, 31 years post-amputation) or ulnar (Subject 2-U, 1.5 years post-amputation) nerves of two amputees. Neural activity was recorded during intended movements of the subject’s phantom fingers and a linear Kalman filter was used to decode the neural data. Microelectrode stimulation of varying amplitudes and frequencies was delivered via single or multiple electrodes to investigate the number, size and quality of sensory percepts that could be evoked. Device performance over time was assessed by measuring: electrode impedances, signal-to-noise ratios (SNRs), stimulation thresholds, number and stability of evoked percepts. Main results. The subjects were able to proportionally, control individual fingers of a virtual robotic hand, with 13 different movements decoded offline (r = 0.48) and two movements decoded online. Electrical stimulation across one USEA evoked >80 sensory percepts. Varying the stimulation parameters modulated percept quality. Devices remained intrafascicularly implanted for the duration of the study with no significant changes in the SNRs or percept thresholds. Significance. This study demonstrated that an array of 96 microelectrodes can be implanted into the human peripheral nervous system for up to 1 month durations. Such an

  8. Identification of target areas for deep brain stimulation in human basal ganglia substructures based on median nerve sensory evoked potential criteria

    PubMed Central

    Klostermann, F; Vesper, J; Curio, G

    2003-01-01

    Objective: In the interventional treatment of movement disorders, the thalamic ventral intermediate nucleus (VIM) and the subthalamic nucleus (STN) are the most relevant electrode targets for deep brain stimulation (DBS). This study tested the value of somatosensory evoked potentials (SEP) for the functional identification of VIM and STN. Methods: Median nerve SEP were recorded from the final stimulation electrodes targeted at STN and VIM. Throughout the stereotactic procedure SEP were recorded during short electrode stops above STN/VIM and within the presumed target areas. After digital filtering, high and low frequency SEP components were analysed separately to parameterise both the 1000 Hz SEP burst and low frequency (<100 Hz) components. Results: SEP recorded in the VIM target region could unequivocally be distinguished from SEP recorded in STN. The 1000 Hz burst signal was significantly larger in VIM than in STN without any overlap of amplitude values. In the low frequency band, a primary high amplitude negativity was obtained in VIM, contrasting with a low amplitude positivity in STN. SEP waveshapes in recordings above target positions resembled SEP obtained in STN. When entering VIM, a sharp amplitude increase was observed over a few millimetres only. Conclusions: Based on SEP criteria, the VIM target but not the STN region can be identified by typical SEP configuration changes, when penetrating the target zone. The approach is independent of the patient's cooperation and vigilance and therefore feasible in general anaesthesia. It provides an easy, reliable, and robust tool for the final assessment of electrode positions at the last instance during electrode implantation when eventual electrode revisions can easily be performed. PMID:12876229

  9. Vagus nerve stimulation delivered during motor rehabilitation improves recovery in a rat model of stroke.

    PubMed

    Khodaparast, Navid; Hays, Seth A; Sloan, Andrew M; Fayyaz, Tabbassum; Hulsey, Daniel R; Rennaker, Robert L; Kilgard, Michael P

    2014-09-01

    Neural plasticity is widely believed to support functional recovery following brain damage. Vagus nerve stimulation paired with different forelimb movements causes long-lasting map plasticity in rat primary motor cortex that is specific to the paired movement. We tested the hypothesis that repeatedly pairing vagus nerve stimulation with upper forelimb movements would improve recovery of motor function in a rat model of stroke. Rats were separated into 3 groups: vagus nerve stimulation during rehabilitation (rehab), vagus nerve stimulation after rehab, and rehab alone. Animals underwent 4 training stages: shaping (motor skill learning), prelesion training, postlesion training, and therapeutic training. Rats were given a unilateral ischemic lesion within motor cortex and implanted with a left vagus nerve cuff. Animals were allowed 1 week of recovery before postlesion baseline training. During the therapeutic training stage, rats received vagus nerve stimulation paired with each successful trial. All 17 trained rats demonstrated significant contralateral forelimb impairment when performing a bradykinesia assessment task. Forelimb function was recovered completely to prelesion levels when vagus nerve stimulation was delivered during rehab training. Alternatively, intensive rehab training alone (without stimulation) failed to restore function to prelesion levels. Delivering the same amount of stimulation after rehab training did not yield improvements compared with rehab alone. These results demonstrate that vagus nerve stimulation repeatedly paired with successful forelimb movements can improve recovery after motor cortex ischemia and may be a viable option for stroke rehabilitation.

  10. Re-evaluation and quantification of the different sources of nerve fibres supplying the rat eye

    PubMed Central

    Cavallotti, Carlo; Frati, Alessandro; Sagnelli, Paolo; Pescosolido, Nicola

    2005-01-01

    The denervation and/or the removal of peripheral nerve ganglia are useful surgical techniques for studying the source and distribution of peripheral nerves in all organs, including the eye. The amount and distribution of the remaining nerve fibres supplying the eye (after sectioning of various types of nervous fibres and/or removal of nerve ganglia) were evaluated in the rat. Male Sprague–Dawley rats were anaesthetized and one or more of the following nervous tissues were removed: superior cervical ganglion, main ciliary ganglion, pterygopalatine ganglion, trigeminal ganglion and the ophthalmic-maxillary nerve. In some animals, chemical sympathectomy was performed by administration of 6-OH dopamine. The eyes were cut in serial sections, but only three regions (cornea, iris and choroid) were harvested and submitted for various nerve fibre staining techniques. The results were quantified and statistically analysed. Superior cervical ganglionectomy and/or chemical sympathectomy induced the destruction of almost all the catecholaminergic nerve fibres in the three examined regions of the rat eye. Removal of the ciliary ganglion (partial parasympathectomy) caused the destruction of about 60% of the cholinergic nerve fibres of the same regions of the rat eye, while subtotal parasympathectomy destroyed about 80% of the cholinergic nerve fibres. Surgical transsection of the ophthalmo-maxillary nerve or the removal of the trigeminal ganglion led to a degeneration of almost all sensitive nerve fibres of the three examined regions of the rat eye. The denervation experiments confirmed the presence of the different types of nerve fibres (sympathetic, parasympathetic and sensitive) in the three studied structures of the rat eye. PMID:15733292

  11. Effect of CRF injected into the median eminence on GH secretion in female rats under different steroid status.

    PubMed

    Puertas, A; Frias, J; Ruiz, E; Ortega, E

    1996-08-01

    To evaluate whether the median eminence (ME) is a site of action of CRF (corticotropin releasing factor) on GH secretion and to determine the possible role of estradiol and progesterone in modifying theses secretion, we injected CRF (0.25, 0.75, 1, and 1.5 nmol of peptide dissolved in 1 microliter of water) directly into the ME in three experimental groups of rats: Long-term ovariectomized (OVX); OVX primed by estradiol (OVX +/- E) and OVX primed by estradiol plus progesterone (OVX +/- EP). Blood was collected to determine GH (30, 60, 90, and 120 min postinjection). Serum T3, T4, and glucose levels were measured in OVX +/- E rats 30 min postinjection. CRF at all doses studied significantly decreased serum GH levels in the three experimental groups. Serum T3, T4, and glucose levels were unchanged after CRF administration. The results suggest that: CRF inhibits "per se" GH secretion, at least in part, by a central action in the ME. The inhibitory effect of CRF on GH is independent of the estrogen/progesterone status of the animal. CRF at ME levels may participate in a variety of stress-related responses, including growth inhibition, through GH suppression.

  12. Food intake increased after injection of adrenaline into the median raphe nucleus of free-feeding rats.

    PubMed

    dos Santos, Rúbia Lima Dias; Mansur, Samira Schultz; Steffens, Sérgio Murilo; Faria, Moacir Serralvo; Marino-Neto, José; Paschoalini, Marta Aparecida

    2009-02-11

    The present study examined the effects of local injections of adrenaline (AD) or noradrenaline (NA) in equimolar doses (6, 20, and 60 nmol) into the median raphe nucleus (MRN) on ingestive and non-ingestive behaviors of free-feeding rats. The results showed that the treatment with AD at doses of 20 and 60 nmol increased food intake. While the hyperphagic response evoked by 60 nmol dose of AD was accompanied by a reduction of the latency to start feeding and an increase in the frequency of feeding, the 20 nmol dose of AD was unable to change these behavioral aspects of feeding response. The meal size and non-ingestive behaviors were not affected by AD treatment in the MRN. While water intake remained unchanged after the treatment with 20 nmol of AD in the MRN, this dose decreased the latency to start drinking. Feeding and drinking behaviors were not affected by treatment with NA in the MRN. These data suggest that adrenergic receptors of MRN participate in mechanisms that control food intake initiation or appetite. In addition, our results also indicate that the availability of energetic substrate could affect the adrenergic influence on MRN neurons since previous data indicated that the injection of AD into the MRN of food restricted rats decreased food intake.

  13. The adrenaline microinjection into the median raphe nucleus induced hypophagic effect in rats submitted to food restriction regimen.

    PubMed

    Maidel, Simone; Lucinda, Aparecida Marcia; de Aquino, Vivian W; Faria, Moacir Serralvo; Paschoalini, Marta Aparecida

    2007-07-11

    The effect of the equimolar doses (6, 20 and 60 nmol) of either adrenaline (AD) or noradrenaline (NA) microinjected into the median raphe nucleus (MR) on feeding behavior of food-restricted rats (15 g/day/rat) was investigated. The data indicated that 20 nmol AD microinjection, but not NA, into the MR decreased the animal food intake. This hypophagic effect induced by AD may be ascribed to a feeding bout conclusion (satiation process) and not to any changes in non-ingestive behaviors induced by drug microinjection. Since equimolar doses of NA failed to change the animal feeding behavior, it is possible to say that AD-induced hypophagia may be due to either changes in tonic stimulatory control exerted by endogenous noradrenaline on MR or to AD-beta(2) receptor activation in the MR. We claim that such activation may be much more importantly exerted by adrenaline-containing afferents to MR neurons involved with ingestive behavior than by noradrenergic inputs.

  14. Feeding behaviour after injection of α-adrenergic receptor agonists into the median raphe nucleus of food-deprived rats.

    PubMed

    Ribas, Anderson Savaris; Flores, Rafael Appel; de Nazareth, Aparecida Marcelino; Faria, Moacir Serralvo; Terenzi, Mariana Graciela; Marino-Neto, José; Paschoalini, Marta Aparecida

    2012-01-18

    This study investigated the participation of median raphe nucleus (MnR) α1-adrenergic receptors in the control of feeding behaviour. The α1-adrenergic agonist phenylephrine (PHE) and α2-adrenergic agonist clonidine (CLON) (at equimolar doses of 0, 6 and 20 nmol) were injected into the MnR of: a) rats submitted to overnight fasting (18 h); or b) rats maintained with 15 g of lab chow/day for 7 days. Immediately after the drug injections, the animals were placed in the feeding chamber and feeding and non-ingestive behaviours such as grooming, rearing, resting, sniffing and locomotion were recorded for 30 min. The results showed that both doses of PHE injected into the MnR of overnight fasted animals decreased food intake accompanied by an increase in the latency to start feeding. A reduction in feeding duration was observed only after treatment of the MnR with the 20 nmol dose of PHE. Both locomotion duration and sniffing frequency increased after injection with the highest dose PHE into the MnR. Feeding frequency and the other non-ingestive behaviours remained unchanged after PHE treatment in the MnR. Both doses of PHE injected into the MnR of food-restricted rats decreased food intake. This hypophagic response was accompanied by a decrease in feeding duration only after treatment of the MnR with the highest dose of PHE. The latency to start feeding and feeding frequency were not affected by injection of either dose of PHE into the MnR. While both doses of PHE increased sniffing duration, the highest dose of PHE increased resting duration and resting frequency. Treatment with CLON into the MnR did not affect feeding behaviour in either of the food deprivation conditions. The present results indicate the inhibitory functional role of α1-adrenergic receptors within the MnR on feeding behaviour. Copyright © 2011 Elsevier Inc. All rights reserved.

  15. Recombinant hNeuritin Promotes Structural and Functional Recovery of Sciatic Nerve Injury in Rats

    PubMed Central

    Wang, Haiyan; Li, Xinli; Shan, Liya; Zhu, Jingling; Chen, Rong; Li, Yuan; Yuan, Wumei; Yang, Lei; Huang, Jin

    2016-01-01

    Neuritin is a new neurotropic factor implicated in nervous system development and plasticity. Studies have shown that Neuritin is upregulated in injured nerves, suggesting that it is involved in nerve repair. To test this hypothesis, we investigated whether recombinant human Neuritin could restore nerve structure and function in a rat model of sciatic nerve injury. Neuritin treatment had a dose-dependent effect on functional recovery 4 weeks after injury, as determined by the walking-track test. Similar trends were observed for gastrocnemius muscular strength and nerve conduction velocity. Additionally, sciatic nerve fiber density and organization as well as degree of remyelination were increased, while growth-associated protein 43 and neurofilament 200 expression was upregulated upon treatment with Neuritin. These findings demonstrate that Neuritin stimulates nerve regeneration and functional recovery and thus promotes the repair of injured sciatic nerves. PMID:28066172

  16. Effects of glycine on electrical and histological properties of a rat peripheral nerve injury model.

    PubMed

    Padilla-Martin, Krystell; Baltazar-Rendon, Bernardo; Gonzalez-Maciel, Angelica; Nuno-Licona, Alberto; Uribe-Escamilla, Rebeca; Hernandez-Romero, Adriana; Ramos, Andrea; Alfaro-Rodriguez, Alfonso

    2009-03-01

    Treatment of peripheral nerve injuries focuses on lesion type, from expectant to interfascicular repair. Many experiments have been undertaken using different factors to facilitate better or faster nerve stump growth: nerve growth factor (NGF), plaque growth factor (PGF), hyaluronic acid, leukemic inhibiting factor, and GABA, etc. Glycine is an inhibitory neurotransmitter in the brain stem and spinal cord, and it also plays a critical role as a modulator of NMDA receptors. We studied the potential regenerative effect of glycine administered for different periods of time and compared results with a control group. The sciatic nerve of Wistar rats was exposed and the electrophysiology procedure was performed: the nerve was cut transversally and stitched back in place with four isolated cardinal 9/0 nylon stitches on each end. Study group rats were administered glycine 40 mM/kg daily for 15, 30, and 60 days, while control group rats were medicated with isotonic saline solution 0.9% for the same time periods. At the end of each study time period, the electrophysiological study was repeated. Animals were sacrificed on the 15th, 30th and 60th postoperative day and the sciatic nerve was exposed and prepared for histological studies. According to our results, glycine was effective in the morphologic regeneration and functional recovery of the sciatic nerve post-injury in Wistar rats with one month administration. We observed that nerve histology with glycine administration was more similar to that of normal nerves.

  17. The role of uninjured nerve in spinal nerve ligated rats points to an improved animal model of neuropathic pain.

    PubMed

    Lee, Doo H; Iyengar, Smriti; Lodge, David

    2003-01-01

    L5 and L6 spinal nerve ligation (SNL) in rats leads to behavioral signs of neuropathic pain including mechanical allodynia. The purposes of this study were to investigate the role of the intact L4 spinal nerve in the development of mechanical allodynia following L5 and L6 SNL and, as a result, to develop a modified model of neuropathic pain. As a first set of experiments, in addition to tight ligation of the left L5 and L6 spinal nerves, the intact L4 spinal nerve was manipulated either (1) by gentle repeated stretching of the L4 spinal nerve immediately after L5 and L6 SNL or (2) by intermittent mechanical stimulation to the ipsilateral paw during the first week after SNL. Tactile sensitivity was measured by determining the foot withdrawal threshold before and after SNL. Mild irritation of L4 spinal nerve and application of mechanical stimuli to the ipsilateral paw significantly increased the development of mechanical allodynia after SNL. In a second set of experiments, SNL was produced by tightly ligating only the left L5 spinal nerve with or without a loop of 5-0 chromic gut placed loosely around the L4 spinal nerve. This additional L4 loop significantly increased long-lasting tactile sensitivity compared to L5 SNL alone. These results suggest that afferent activity of the intact L4 spinal nerve aids in the development of mechanical allodynia in the SNL model of neuropathic pain. The addition of a chromic gut loop around the intact L4 spinal nerve can augment the development of mechanical allodynia following SNL of L5. We propose this latter as a useful and practical animal model of neuropathic pain.

  18. The Histological Effects of Ozone Therapy on Sciatic Nerve Crush Injury in Rats.

    PubMed

    Somay, Hakan; Emon, Selin Tural; Uslu, Serap; Orakdogen, Metin; Meric, Zeynep Cingu; Ince, Umit; Hakan, Tayfun

    2017-09-01

    Peripheral nerve injury is a common, important problem that lacks a definitive, effective treatment. It can cause neurologic deficits ranging from paresthesia to paralysis. This study evaluated the effect of ozone therapy on sciatic nerve crush injury in rats. Twenty-four male rats were divided into control sham surgery, sciatic nerve injury, and sciatic nerve injury with ozone groups (each n = 8). The sciatic nerve injury was inflicted via De Koning's crush-force method. The sciatic nerve injury group received medical air and the sciatic nerve injury ozone group received 0.7 mg/kg ozone. Sciatic nerve samples were obtained 4 weeks after injury. Vascular congestion, vacuolization, edema formation, S100 expression, and the thicknesses of the perineurium and endoneurium and diameter of the injured sciatic nerves were evaluated. The diameter of the sciatic nerve and thicknesses of the perineurium and epineurium were significantly greater in the sciatic nerve injury group (P < 0.05) and significantly less in the sciatic nerve injury with ozone group (P < 0.001). High S100 immunoreactivity was seen in the sciatic nerve injury group compared with the other 2 groups (P < 0.05). The distributions of vascular congestion and vacuolization were significantly less in the sciatic nerve injury with ozone group (P < 0.05). Ozone therapy improved sciatic nerve injury recovery without causing an increase in fibrotic tissue. Ozone reduced fibrosis, vascular congestion, vacuolization, and edema in rodents. Ozone treatment might be used to assist in sciatic nerve injury. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Effect of bleeding on nerve regeneration and epineural scar formation in rat sciatic nerves: an experimental study.

    PubMed

    Servet, Erkan; Bekler, Halil; Kılınçoğlu, Volkan; Özler, Turhan; Özkut, Afşar

    2016-01-01

    Epineural scar formation is one of the most significant negative factors affecting surgical repair after peripheral nerve injury. The scar tissue mechanically hinders axonal regeneration and causes adhesions between nerves and surrounding tissues. A hemostatic agent Ankaferd Blood Stopper (ABS; İmmun Gıda İlaç Kozmetik San. ve Tic. Ltd. Şti., Istanbul, Turkey) has not been previously used. Decreasing the postoperative bleeding and adhesions between nerve and surrounding tissues will prevent the formation of scar tissue, as well as corresponding compressive neuropathy and/or deceleration of axonal regeneration. The purpose of this experimental study was to investigate the effects of bleeding on nerve healing and scar tissue after repair of peripheral nerve injuries. The right sciatic nerve of 30 Sprague-Dawley male rats (weighing 260-330 g) was cut 1.5 cm proximal to the trifurcation and repaired primarily with 8/0 sutures using epineural technique. The rats were then divided into 3 groups. Saline was applied in Group 1 (n=10), ABS in Group 2 (n=10), and heparin in Group 3 (n=10) for 5 minutes to the repair site and surrounding tissues. In each group, electrophysiological measurements were performed with electromyography (EMG) at postoperative week 12. Magnetic resonance diffusion tensor imaging was used at week 12. Macroscopical and histopathological evaluations were conducted after sacrificing the rats at week 24 with total excision of the repaired sciatic nerves and surrounding tissues. The ABS and saline groups showed better healing than the heparin group. The ABS and saline groups were better in the histopathologic evaluations, but there was no statistically significant difference between the 2 groups. Statistically significant differences were not found between the 3 groups. Significant results may be obtained with larger studies.

  20. AB320. SPR-47 Monitoring nerve activity during bladder filling in a rat model

    PubMed Central

    Tiwari, Ekta; Lemay, Michel A.; Braverman, Alan S.; Obeid, Iyad; Barbe, Mary F.; Ruggieri, Michael R.

    2016-01-01

    Objective Surgical rerouting of neuronal pathways may allow functional reinnervation of the bladder. We aim to develop techniques to monitor afferent (sensory) nerve activity during bladder filling in normal intact bladders for eventual application to monitoring sensory reinnervation of the bladder following nerve transfer. Methods Electroneurogram recordings were performed in anesthetized rats under isoflurane (1–2% induction dose, inhalation) of: (I) sciatic nerves during stimulation of the hindpaw with Semmes-Weinstein monofilaments of varying forces (10–300 g); and (II) bladder nerves during bladder filling with infusion rate of 0.5 mL/min, in acute experiments. Bipolar cuff electrodes were wrapped around the sciatic nerve (n=7) and ureter (and associated bladder nerves) proximal to the bladder wall (n=7), to record sciatic and bladder nerve discharges, respectively. The sciatic nerve was transected between the spinal cord and the electrode, to eliminate efferent nerve signals and record afferent fibers discharge only with hindpaw stimulation. Whereas, recordings were made of the discharges of both afferent and efferent fibers from bladder nerves during bladder filling. All recordings were performed using a low noise amplifier (SR560, filtered 300 Hz–10 kHz, gain ×10k), sampled at 20 kHz using PowerLab software (AD Instruments) and displayed using LabChart software. Bladder pressure was also recorded during filling. Results Sciatic nerve recordings consistently showed increased afferent fibers discharge with increased size of monofilament used to stimulate the hindpaw, with the highest discharge observed with the 300 g monofilament and lowest with 10 g. In contrast, recording from bladder nerves showed that combined afferent and efferent discharges increased substantially in response to bladder filling in 2 of 7 rats, and increased moderately in 2 other rats. However, there was no response in the remaining rats, perhaps due to nerve damage during cuff