Acute Nerve Injury Research Articles

Electromyographic evaluation of the effectiveness of electroacupuncture in experimental damage of nervus radialis and nervus ulnaris in rabbits

Many different acupuncture points and techniques have been used in the treatment of peripheral nerve injuries. It is known that alternative and complementary medicine techniques have become popular in the treatment of nerve damage in recent years. In this study, it was aimed to investigate the effectiveness of electroacupuncture in acute and chronic radial and ulnar nerve injuries. Electromyographic measurements were made to evaluate the effectiveness of electroacupuncture. In the study, the rabbits were divided into four groups namely acute nerve injury (ANI) group, chronic nerve injury (CNI) group, positive control (PC) group and negative control (NC) group. In the ANI, CNI and PC groups, damage was created on the nervus radialis and nervus ulnaris by applying pressure for 60 seconds using a hemostatic forceps under anesthesia. No damage was created in the NC group. Fifteen sessions of electroacupuncture were applied to the rabbits in the ANI, CNI, and NC groups every other day using LI-4, LI-10, LR-3, and ST-36 electroacupuncture points. Electroacupuncture was not applied to the rabbits in the PC group. Electromyographic examinations of both forelimbs of rabbits were performed during electroacupuncture applications. In the study, rabbits in the ANI group were measured at first amplitudes of 9.78 ? 1.66, and final amplitudes of 18.94 ? 1.83 (p ? 0.01). Rabbits in the CNI group were measured at first amplitudes of 11.34 ? 1.52, and final amplitudes of 16.03 ? 1.35 ( p ? 0.01). However, no statistically significant difference was found between the first and last latency values for both groups of rabbits. As a result, it was determined that electroacupuncture is an effective treatment method for both acute and chronic nerve injuries, as well as being more effective in acute cases than in chronic cases.

Siponimod exerts neuroprotective effects on the retina and higher visual pathway through neuronal S1PR1 in experimental glaucoma.

Sphingosine-1-phosphate receptor (S1PR) signaling regulates diverse pathophysiological processes in the central nervous system. The role of S1PR signaling in neurodegenerative conditions is still largely unidentified. Siponimod is a specific modulator of S1P1 and S1P5 receptors, an immunosuppressant drug for managing secondary progressive multiple sclerosis. We investigated its neuroprotective properties in vivo on the retina and the brain in an optic nerve injury model induced by a chronic increase in intraocular pressure or acute N-methyl-D-aspartate excitotoxicity. Neuronal-specific deletion of sphingosine-1-phosphate receptor (S1PR1) was carried out by expressing AAV-PHP.eB-Cre recombinase under Syn1 promoter in S1PR1flox/flox mice to define the role of S1PR1 in neurons. Inner retinal electrophysiological responses, along with histological and immunofluorescence analysis of the retina and optic nerve tissues, indicated significant neuroprotective effects of siponimod when administered orally via diet in chronic and acute optic nerve injury models. Further, siponimod treatment showed significant protection against trans-neuronal degenerative changes in the higher visual center of the brain induced by optic nerve injury. Siponimod treatment also reduced microglial activation and reactive gliosis along the visual pathway. Our results showed that siponimod markedly upregulated neuroprotective Akt and Erk1/2 activation in the retina and the brain. Neuronal-specific deletion of S1PR1 enhanced retinal and dorsolateral geniculate nucleus degenerative changes in a chronic optic nerve injury condition and attenuated protective effects of siponimod. In summary, our data demonstrated that S1PR1 signaling plays a vital role in the retinal ganglion cell and dorsolateral geniculate nucleus neuronal survival in experimental glaucoma, and siponimod exerts direct neuroprotective effects through S1PR1 in neurons in the central nervous system independent of its peripheral immuno-modulatory effects. Our findings suggest that neuronal S1PR1 is a neuroprotective therapeutic target and its modulation by siponimod has positive implications in glaucoma conditions.

Physiotherapy Perspective in the Rehabilitation of Traumatic Brachial Plexus Injury in a Patient with Polytrauma: A Case Report Emphasising an Early Approach

Traumatic peripheral nerve damage from Road Traffic Accidents (RTA) can cause severe impairment and loss of function in the upper and lower limbs. A significant portion of acute peripheral nerve injuries affects the upper limb, particularly the brachial plexus. The treatment for complete brachial plexus injury may involve surgery and intensive physiotherapy to help the nerves regenerate and reinnervate the muscles. A 17-year-old male was referred to the Neurology department from a primary healthcare centre after being involved in RTA that resulted in a fall on the right-side. Investigatory findings revealed a head injury with Subarachnoid Haemorrhage (SAH), fractures of the right tibia shaft, right clavicle lateral shaft, and right lower limb. Following surgery, the patient experienced difficulty in performing movements with the right upper limb, along with pain and tingling sensations. As a result, the patient was referred to physiotherapy. During physiotherapy, the patient received sensory re-education sessions lasting 15-20 minutes each, as well as bilateral training sessions lasting 20 minutes each, for a total of four weeks. Over the course of the treatment, the patient demonstrated overall improvement in hand function, including proper grasp and opposition. This improvement was reflected in the brachial assessment tool, Upper Extremity (UE) functional index, and functional independence measure. These positive outcomes underscore the importance of early neuro-physiotherapeutic rehabilitation for patients with brachial plexus injuries, as it can significantly enhance their overall well-being and quality of life.

Hip abductor dysfunction following total hip arthroplasty by modified direct lateral approach: Assessment by quantitative electromyography

Abstract Background The use of the direct lateral approach and its modifications for total hip arthroplasty (THA) may lead to postoperative abductor weakness. Assessment of abductor muscle function by the use of quantitative electromyography (EMG) aims to investigate the nature of abductor muscle dysfunction. Methods We conducted a study on 40 patients who had hip replacement through the modified direct lateral approach. EMG was performed before surgery on the affected and normal sides and repeated on the operated side after surgery by 6 and 12 weeks. Analysis of EMG of the three abductor muscles was done in all patients. Results EMG evidence of acute denervation of hip abductors was present in 15 hips (37.5%) after 6 weeks. Improvement of EMG findings occurred in 8 out of 15 patients. Quantitative electromyography (QEMG) showed early significant increase in amplitude in all muscles and decrease in duration in gluteus medius (G. Med) with a pattern of acute nerve injury. At 12 weeks, the values of duration, amplitude, and phase were insignificantly different from the preoperative values signifying the return of near normal muscle activity. Conclusion The use of modified direct lateral approach can cause denervation of hip abductors. It is common in the early postoperative weeks. However, it tends to improve and the residual weakness in some patients is not marked. Quantitative electromyography showed that partial denervation is related to superior gluteal nerve stretching and not to direct injury of the terminal branches of the nerve through the incision.

Magnetic resonance imaging assessment of the therapeutic effect of combined electroacupuncture and stem cells in acute peripheral nerve injury.

Objectives: This study aimed to evaluate the therapeutic effect of a combination of Bone Mesenchymal stem cells (BMSCs) transplantation and Electroacupuncture (EA) for acute sciatic nerve injury in rats using magnetic resonance. Methods: Ninety-two male adult healthy Sprague-Dawley rats were randomly divided into the EA+BMSCs group, EA group, MSCs group, and PBS group (control). Electroacupuncture was performed on a rat receiving EA treatment at Huantiao (GB30) and Zusanli (ST36). T2 values and diffusion tensor imaging (DTI) derived from multiparametric magnetic resonance imaging (MRI), histological assessments, and immunohistochemistry was used to monitor nerve regeneration. Walking track analysis was used to assess nerve functional recovery. Repeated-measures one-way analysis of variance was used to evaluate the significance of T2, DTI, and SFI values among the four groups. One-way analysis of variance was used for comparing the histological characteristics. Bonferroni test was used for multiple pairwise comparisons at each time point. Results: In terms of FA, the EA+BMSCs and EA groups had faster recovery than PBS (control) in all time points after surgery, and the EA+BMSCs group recovered better than the BMSCs group at 3 weeks (P ≤ 0.008). FA values were higher in the EA group than in the BMSCs group at 4 weeks (P ≤ 0.008). In terms of RD, the EA+BMSCs group recovered better than the BMSCs group at 2 and 4 weeks (P ≤ 0.008). Immunofluorescence staining for axon guidance molecule netrin-1 revealed that it was significantly higher in the EA+BMSCs subgroup and EA subgroup than it was in the control (PBS) subgroup at 1-3 weeks (P < 0.001). Immunofluorescence staining for S100 showed the continuity of nerve fibers recovered more quickly in the EA+BMSCs subgroup than in the BMSCs subgroup. Conclusion: Our research revealed that a combination of MSCs and EA can provide both topological and biomolecular guidance to promote axonal extension, myelin regeneration, and functional recovery after PNI. EA not only promotes nerve repair on its own, but also enhanced the beneficial effects of stem cell treatment and the secretion of netrin 1, a guidance regeneration factor, and promotes the orderly growth of nerve fibers. These PNI repairs could be monitored non-invasively and in situ by MRI. The FA and RD values derived from MRI could be sensitive biomarkers to reflect the PNI repair process.

Histopathological, immunohistochemical and biochemical evaluation of electroacupuncture treatment of nervus radialis and nervus ulnaris injuries in rabbits.

The aim of this study was to evaluate the efficacy of electroacupuncture in acute and chronic phases of radial and ulnar nerve injuries in histopathological, immunohistochemical and biochemical aspects. In the study, the rabbits were divided into four groups namely acute nerve injury (ANI) group, chronic nerve injury (CNI) group, positive control (PC) group and negative control (NC) group. In the ANI, CNI and PC groups, damage was created on the nervus radialis and nervus ulnaris by applying pressure for 60 seconds using a hemostatic forceps under anesthesia. No damage was created in the NC group. Fifteen sessions of electroacupuncture were applied to the rabbits in the ANI, CNI, and NC groups every other day using LI-4 (Large Intestine Meridian-4, He Gu), LI-10 (Large Intestine Meridian-10, Shou San Li), LR-3 (Liver Meridian-3, Tai Chong), and ST-36 (Stomach Meridian-36, Zusanli) electroacupuncture points. Electroacupuncture was not applied to the rabbits in the PC group. Decapitation was performed under general anesthesia at the end of electroacupuncture applications. After the euthanasia procedure, the samples obtained were evaluated for histopathological, immunohistochemical and biochemical parameters. In conclusion, degenerative foci in the treatment groups were found to be fewer than in the PC group whereas NGF and S-100 immunoreactivity were higher in the treatment groups than in the PC group. Whereas no statistically significant difference was observed between the treatment groups and the NC group in terms of oxidative stress factors, there was a statistically significant difference between the treatment groups and the PC group. In light of all these data, we have concluded that electroacupuncture is an effective treatment method for peripheral nerve injuries.

A Drosophila ortholog of Toll‐like receptors modulates c‐Jun N‐terminal kinase signaling and protects against tau‐mediated neurodegeneration independent of innate immune response

AbstractBackgroundInnate immunity is dysregulated in aging and neurodegenerative diseases, and Toll‐like receptors (TLRs) play a central role in innate immune response. Nine Toll family receptors (Toll‐1 to Toll‐9) exist in Drosophila, and Toll‐9 is structurally most closely related to mammalian TLRs such as TLR1, 2, 6, 10. However, physiological roles of Toll‐9 in innate immunity and neurodegeneration are largely unknown. In this study, we examined roles of Toll‐9 in fly brains under neurodegenerative conditions.MethodWe systematically investigated potential roles of Toll‐9 in the maintenance of the brain integrity under neurodegenerative conditions, using Drosophila models of acute axon injury and human tau‐mediated neurodegeneration.ResultExpression level of Toll‐9 was very low in brains under normal condition but was dramatically increased upon acute nerve injury, suggesting a potential role of Toll‐9 in neurodegeneration. Innate immune response including induction of antimicrobial peptides and glial phagocytic activity of degenerating neurons were activated by nerve injury in fly brains, though Toll‐9 knockout did not affect these responses. Interestingly, however, Toll‐9 knockout significantly impaired activation of stress signaling cascades including c‐Jun N‐terminal kinase pathway. To ask whether Toll‐9 modify severity of neurodegeneration, we employed a fly model of tauopathy and found that Toll‐9 knockdown significantly exacerbated axon degeneration accompanied by pathological tau phosphorylation.ConclusionThese results demonstrate that Drosophila Toll‐9 confers neuroprotective effects through activation of stress kinase signaling independent of induction of innate immune genes, which may provide insights into the pathogenesis of neurodegenerative diseases.

An Epidemiological and Etiological Analysis of 5026 Peripheral Nerve Lesions from a European Level I Trauma Center.

Background: Peripheral nerve lesions are associated with debilitating long-term consequences. Albeit being essential for evidence-based clinical decision making, epidemiological and etiological data are scarce. We therefore aimed to comprehensively analyze epidemiological and etiological factors of peripheral nerve lesions in one of the largest cohorts. Methods: We screened a total of 110,667 patients treated at our level I trauma center between January 2012 and July 2020 for nerve lesions. Subsequently, demographics, etiologies, concomitant injuries, and lesion characteristics were analyzed. Results: A total of 5026 patients, predominantly young males suffering from non-work-related nerve injuries, were treated. Proximal levels of injury were more likely to be accompanied by fractures, whereas more distal injuries with concomitant vessel or tendon injury. Main causes were 54.6% lacerations. Acute traumatic nerve injury was treated within 24 h in 55.9% of cases. Conclusions: Given the young age of affected patients, early diagnosis and treatment in specialized centers may facilitate their early return to work and improve long-term functional outcomes. The data show the importance of a special attention on nerve injuries, which may be masked by large accompanying injuries. New findings on lesion characteristics of selected subgroups and accompanying circumstances can support a change in treatment strategies.

High-frequency electrical stimulation attenuates neuronal release of inflammatory mediators and ameliorates neuropathic pain

BackgroundNeuroinflammation is an important driver of acute and chronic pain states. Therefore, targeting molecular mediators of neuroinflammation may present an opportunity for developing novel pain therapies. In preclinical models of neuroinflammatory pain, calcitonin gene-related peptide (CGRP), substance P and high mobility group box 1 protein (HMGB1) are molecules synthesized and released by sensory neurons which activate inflammation and pain. High-frequency electrical nerve stimulation (HFES) has achieved clinical success as an analgesic modality, but the underlying mechanism is unknown. Here, we reasoned that HFES inhibits neuroinflammatory mediator release by sensory neurons to reduce pain.MethodsUtilizing in vitro and in vivo assays, we assessed the modulating effects of HFES on neuroinflammatory mediator release by activated sensory neurons. Dorsal root ganglia (DRG) neurons harvested from wildtype or transgenic mice expressing channelrhodopsin-2 (ChR2) were cultured on micro-electrode arrays, and effect of HFES on optogenetic- or capsaicin-induced neuroinflammatory mediator release was determined. Additionally, the effects of HFES on local neuroinflammatory mediator release and hyperalgesia was assessed in vivo using optogenetic paw stimulation and the neuropathic pain model of chronic constriction injury (CCI) of the sciatic nerve.ResultsLight- or capsaicin-evoked neuroinflammatory mediator release from cultured transgenic DRG sensory neurons was significantly reduced by concurrent HFES (10 kHz). In agreement with these findings, elevated levels of neuroinflammatory mediators were detected in the affected paw following optogenetic stimulation or CCI and were significantly attenuated using HFES (20.6 kHz for 10 min) delivered once daily for 3 days.ConclusionThese studies reveal a previously unidentified mechanism for the pain-modulating effect of HFES in the setting of acute and chronic nerve injury. The results support the mechanistic insight that HFES may reset sensory neurons into a less pro-inflammatory state via inhibiting the release of neuroinflammatory mediators resulting in reduced inflammation and pain.

Anti-inflammatory effect of glucagon-like Peptide-1 receptor agonist on the neurosensory retina in an acute optic nerve injury rat model

PurposeTo explore the possibility of using glucagon-like peptide-1 receptor agonist (GLP-1RA) as a new treatment for neuroinflammation, by analyzing retinal pathological changes in an optic nerve crush rat model. MethodsEight-week-old male Sprague-Dawley rats were divided into lixisenatide (LIX, n = 10), traumatic control (T-CON, n = 10), and normal control (n = 5) groups. The optic nerves of left eyes in the LIX and T-CON groups were crushed in a standardized manner. The LIX group was treated with subcutaneous injections of lixisenatide (200 μg/kg/day) for 5 days. One week after initiating treatment, quantitative polymerase chain reaction, Western blot, and immunohistochemistry analyses were performed on the retinal tissues of each group to identify inflammatory markers. ResultsThe LIX group showed significantly lower mRNA levels of interleukin 1 beta (IL-1β), tumor necrosis factor-alpha (TNF-α), thioredoxin interacting protein (TXNIP), and glial fibrillary acidic protein (GFAP) than the T-CON group. Also, the LIX group exhibited decreased TXNIP and GFAP expression compared with the T-CON group, and similar expression to the normal control group, according to Western blot analysis. Significantly increased immunohistochemistry staining of Brn3a and decreased TUNEL staining were seen in the LIX group compared with the T-CON group, indicating that lixisenatide contributes to retinal ganglion cell survival in cases of acute optic nerve injury. ConclusionsNeuroinflammation was significantly reduced in lixisenatide-treated retinas compared with untreated retinas in our acute optic nerve injury rat model. The neuroprotective effect of lixisenatide indicates that it can serve a new treatment option against clinically intractable traumatic optic neuropathy.

Pulsed field ablation for pulmonary vein isolation: real-world experience and characterization of the antral lesion size compared with cryoballoon ablation.

Pulsed field ablation (PFA) is a new, non-thermal technology in the treatment of atrial fibrillation (AF). Early investigations have shown a promising safety profile with durable pulmonary vein isolation (PVI) and large antral lesions. However, clinical data remains scarce. We investigated a cohort of 43 patients. Twenty-three patients underwent PVI with PFA in our hospital and we analyzed them with regard to procedural characteristics and with regard to the size of acute antral lesion which was estimated by using an electroanatomical map of the left atrium (LA). We compared these data with data of 20 patients who had undergone cryoballon (CB) PVI in our hospital. We could show acute isolation of all veins in all patients (100% PFA, 100% CB). Post-ablation high-density mapping revealed no early reconnection (0%). The acute antral lesion size of PFA was significantly higher compared to the CB (67.03 ± 12.69% vs. 57.39 ± 10.91%, p = 0.01). In the PFA group, we found no acute phrenic nerve injury, no major or minor bleeding, and no tamponade but one (4.34%) patient suffered from a stroke. Transient hypotension was observed frequently as well as transient bradycardia or asystole episodes requiring right ventricular pacing. In the CB group, no complications occurred. Furthermore, we discuss practical issues on PFA procedures. PFA is a promising technology with high acute PV isolation rate and large antral lesions compared to CB. However, larger trials with more patients and data on long-term freedom of AF but also complications are needed.

Facial Nerve Repair following Acute Nerve Injury.

Background Acute facial nerve iatrogenic or traumatic injury warrants rapid management with the goal of reestablishing nerve continuity within 72 hours. However, reconstructive efforts should be performed up to 12 months from the time of injury since facial musculature may still be viable and thus facial tone and function may be salvaged. Methods Data of all patients who underwent facial nerve repair following iatrogenic or traumatic injury were retrospectively collected and assessed. Paralysis etiology, demographics, operative data, postoperative course, and outcome were examined. Results Twenty patients underwent facial nerve repair during the years 2004 to 2019. Data were available for 16 of them. Iatrogenic injury was the common category ( n = 13, 81%) with parotidectomy due to primary parotid gland malignancy being the common surgery ( n = 7, 44%). Nerve repair was most commonly performed during the first 72 hours of injury ( n = 12, 75%) and most of the patients underwent nerve graft repair ( n = 15, 94%). Outcome was available for 12 patients, all of which remained with some degree of facial paresis. Six patients suffered from complete facial paralysis (50%) and three underwent secondary facial reanimation (25%). There were no major operative or postoperative complications. Conclusion Iatrogenic and traumatic facial nerve injuries are common etiologies of acquired facial paralysis. In such cases, immediate repair should be performed. For patients presenting with facial paralysis following previous surgery or trauma, nerve repair should be considered up to at least 6 months of injury. Longstanding paralysis is best treated with standard facial reanimation procedures.

Effect of Amniotic Membrane Nerve Wrapping in Final Results of Traumatic Peripheral Nerve Repair.

BACKGROUNDPreventing perineural adhesions and scars formation in the traumatic peripheral injuries is very important on the recovery process. We aimed to evaluate the effect of using the amniotic membrane wrapping on the results of surgical treatment of damaged peripheral nerves.METHODSThis cohort study included 30 patients with symptoms of acute peripheral nerve injuries due to penetrating trauma in the forearm or wrist in January 2019 to November 2020 referred to the Hand and Microsurgery Department, 15 Khordad Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran. In 15 patients, after nerve repair, amniotic membrane coverage was used around the nerve, all patients were followed for 12 months. Ultrasound study for neuroma formation and nerve regeneration was determined based on EMG and NCV findings. The modified Medical Research Councile classification (MRCC) was used to evaluate of motor and sensory recovery. RESULTSIn the amniotic membrane wrapping group, all patients had nerve regeneration and functional nerve recovery occurred after 12 months. In the control group, 5 patients (33.4%) did not have nerve recovery and had functional and sensory impairment. In terms of functional capabilities; there was a significant difference in pinch strength, grip power and MRCC scoring between the two groups. Moreover, the mean volume of neuroma in these patients who used amniotic membrane covering was 2.7 mm3 and in the control group, it was 3.9 mm3 (P=0.001). Five patients who did not have a damaged nerve, the neuroma volume was 4.8 ± 0.9 mm3.CONCLUSIONThe use of amniotic membrane covering is effective methods in the improve results of peripheral nerve repair and nerve function recovery.

Clinical significance of bispectral index monitoring in patients with acute severe carbon monoxide poisoning

Objective: To analyze the correlation of bispectral index (BIS) with the prognosis of patients with acute severe carbon monoxide poisoning (ASCMP) and its predictive value of adverse outcomes. Methods: In March 2021, 106 ASCMP patients who were treated in Harrison International Peace Hospital Affiliated to Hebei Medical University from January 2019 to December 2020 were taken as research objects. All patients underwent 24-hour BIS monitoring after admission, and were divided into good prognosis group (n=75) and poor prognosis group (n=31) according to the prognosis of the patients' cranial nerve function after 60 d. The general conditions, Acute Physiology and Chronic Health Evaluation Ⅱ (APACHEⅡ) score, Glasgow Coma Scale (GCS) score at admission and 24-hour BIS mean were compared between the two groups. Pearson correlation analysis was used to analyze the correlations between the 24-hour BIS mean and GCS score at admission, APACHEⅡ score and coma time. The receiver operating characteristic (ROC) curve was drawn to analyze the predictive value of 24-hour BIS mean, GCS score at admission, APACHEⅡ score and coma time on adverse outcome of ASCMP patients. Results: The coma time and APACHEⅡ score of the patients in the poor prognosis group were significantly higher than those in the good prognosis group, the GCS score at admission and 24-hour BIS mean were significantly lower than those in the good prognosis group (P<0.05) . Pearson correlation analysis showed that the 24-hour BIS mean was positively correlated with the GCS score at admission, and negatively correlated with the APACHEⅡ score, coma time (r=0.675, -0.700, -0.565, P<0.001) . The 24-hour BIS mean had the highest predictive value for adverse outcome of ASCMP patients, with a cut-off value of 74, the area under the curve was 0.883 (95%CI: 0.814-0.951, P<0.001) , and the sensitivity and specificity were 73.3% and 87.1%, respectively. Conclusion: The 24-hour BIS mean has a good correlation with the acute brain nerve injury, the severity of the disease and coma time of patients with ASCMP. And it has a high predictive value for the adverse outcome in patients with ASCMP.

Recovering the regenerative potential in chronically injured nerves by using conditioning electrical stimulation.

Chronically injured nerves pose a significant clinical challenge despite surgical management. There is no clinically feasible perioperative technique to upregulate a proregenerative environment in a chronic nerve injury. Conditioning electrical stimulation (CES) significantly improves sensorimotor recovery following acute nerve injury to the tibial and common fibular nerves. The authors' objective was to determine if CES could foster a proregenerative environment following chronically injured nerve reconstruction. The tibial nerve of 60 Sprague Dawley rats was cut, and the proximal ends were inserted into the hamstring muscles to prevent spontaneous reinnervation. Eleven weeks postinjury, these chronically injured animals were randomized, and half were treated with CES proximal to the tibial nerve cut site. Three days later, 24 animals were killed to evaluate the effects of CES on the expression of regeneration-associated genes at the cell body (n = 18) and Schwann cell proliferation (n = 6). In the remaining animals, the tibial nerve defect was reconstructed using a 10-mm isograft. Length of nerve regeneration was assessed 3 weeks postgrafting (n = 16), and functional recovery was evaluated weekly between 7 and 19 weeks of regeneration (n = 20). Three weeks after nerve isograft surgery, tibial nerves treated with CES prior to grafting had a significantly longer length of nerve regeneration (p < 0.01). Von Frey analysis identified improved sensory recovery among animals treated with CES (p < 0.01). Motor reinnervation, assessed by kinetics, kinematics, and skilled motor tasks, showed significant recovery (p < 0.05 to p < 0.001). These findings were supported by immunohistochemical quantification of motor endplate reinnervation (p < 0.05). Mechanisms to support the role of CES in reinvigorating the regenerative response were assessed, and it was demonstrated that CES increased the proliferation of Schwann cells in chronically injured nerves (p < 0.05). Furthermore, CES upregulated regeneration-associated gene expression to increase growth-associated protein-43 (GAP-43), phosphorylated cAMP response element binding protein (pCREB) at the neuronal cell bodies, and upregulated glial fibrillary acidic protein expression in the surrounding satellite glial cells (p < 0.05 to p < 0.001). Regeneration following chronic axotomy is impaired due to downregulation of the proregenerative environment generated following nerve injury. CES delivered to a chronically injured nerve influences the cell body and the nerve to re-upregulate an environment that accelerates axon regeneration, resulting in significant improvements in sensory and motor functional recovery. Percutaneous CES may be a preoperative strategy to significantly improve outcomes for patients undergoing delayed nerve reconstruction.

282 Follow-up for Evaluation for Nerve Repair Surgery: The Role of Socioeconomic and Geographic Factors in Victims of Violent Nerve Injury

OBJECTIVES/GOALS: We have created the first-ever database for all patients who have acute peripheral nerve injuries. Our goal is to use this data to construct two clinical scoring systems to facilitate triaging by emergency room physicians by 1.) identifying patients who would likely benefit from a nerve surgery, and 2.) identify patients who are less likely to follow up. METHODS/STUDY POPULATION: Based on 2,606 consult emails from the Washington University in St. Louiss Division of Plastic and Reconstructive Surgery, from 2013 to 2019, we have identified more than 600 patient cases in which patients presented after an injury with any kind of nerve deficit. We have defined nerve deficits as any abnormality on motor or sensory exam of the extremities, excluding those younger than 18 years old and those with other disease processes that may affect function of the peripheral nervous system. Data for these patients was collected from electronic medical records and include handedness, nerve injured, operative details, area deprivation index decile, mechanism of injury, insurance and employment status, and whether injuries were a result of work or violence. RESULTS/ANTICIPATED RESULTS: Our plan is to provide the first descriptive statistics for such a population, as well as multiple regression analysis for our two endpoints, loss to follow up and need for surgery. Following regression analysis, we also look to perform cluster analysis to further study co-occurring clinical and social features that affect our endpoints. We are excitedly awaiting to perform the analysis after the final data has been collected. DISCUSSION/SIGNIFICANCE: Nerve injury is a common symptom of penetrating injuries. Many of the socioeconomic factors associated with increased risk for violent injury are also risk factors for decreased rates of follow up. This problem is particularly worrisome given that nerve repair surgery is only viable as an option to return function within the first year after injury.

측두공 내 종양을 암시하는 안면마비 표정의 특성

Background : The objective of this study was to analyze the characteristics of facial expressions by their pathogenesis in subjects with chronic facial paralysis and to describe the partial defect of facial function in elucidating the etiology of facial paralysis. Materials and Methods : The etiology of chronic facial paralysis could be categorized into 3 groups: Group I, total resection without any reanimation surgery; Group II, acute facial nerve injury such as Bell’s palsy, and Group III, facial nerve resection and anastomosis. There was a total number of 104 subjects included in this study. Each subject with chronic facial paralysis and were investigated based on the severity of synkinesis, regression of muscular volume, latency and amplitude in electromyography, and facial movement by House-Brackmann grade system. Results : Subjects from the Group I had no synkinesis with profound regression of muscular volume, H-B grade 5.7 ± 0.34. Subjects from the Group II had moderate to severe synkinesis with moderate to severe regression of muscular volume, H-B grade 3.4 ± 0.96. In this group, thirteen subjects with atypical facial expression also had an incidental finding of a hidden mass in the intratemporal area. Lastly, subjects from the Group III had severe synkinesis without regression of muscular volume, H-B grade 3.7 ± 0.76. Conclusions : With careful examination of facial expression, a crucial point for elucidating the pathogenesis of facial paralysis may be provided. Severe facial palsy without muscular regression may indicate an incidental finding of a hidden mass in the intratemporal area.

Nerve repair and cable grafting in acute facial nerve injury

Facial paralysis can lead to detrimental effects on patient quality of life and impair social engagement. Accordingly, it is vital that acute injuries be triaged and managed appropriately to ensure optimal functional outcome for the patent. Here we will discuss the potential etiologies of acute facial nerve injury, particularly those that are amenable to primary repair or reconstruction with cable grafting. We will highlight options for management, the associated operative technique, and the expected recovery of function in an evidence-based fashion.

Histological examination of the effects of epidermal growth factor on regeneration of acute peripheral nerve injuries on rabbit model.

Peripheral nerve injuries are one of the most common and costly injuries especially in the young population. In this study, it is aimed to determine the histological role of epidermal growth factor (EGF) in nerve regeneration with an acute damage made on sciatic nerve in the rabbit model. We used 18 New Zealand rabbits (nine in control group and nine in experimental group). Each group was divided into two groups consisting of five rabbits planned for diameter measurement and four rabbits planned for spatial measurement. The sciatic nerve exploration in the right flank of each animal, full-thickness nerve damage, and then epineural repair was made by a single researcher. 10 µg/kg EGF was given to the repair area of the experimental group and five more EGF injections were given to the experimental group every other day postoperatively. In the control group, we used saline solution. Rabbits were observed for 8 weeks. During follow-up, two rabbits died. At the end of 8 weeks, the nerve tissue of each animal was evaluated histologically and morphologically. In the experimental group consisting of five rabbits, the mean thickness of connective tissue (epineurium+ mesoneurium) was 156,867 µm; while, in the control group, the thickness was 25,170 µm. In the other groups, the numerical increase in epineurium and mesoneurium areas was detected in the EGF (+) group as a result of the comparative spatial measurements. Epineurium and mesoneurium enlargement was observed in the EGF-given group. Adipocyte and capillary increase was observed in connective tissue. EGF increases epineurium and mesoneurium diameters in peripheral connective tissue in acute peripheral nerve injury regeneration. However, further studies are needed to understand this effect clinically and physiologically.

PENGGUNAAN LASER SEBAGAI TERAPI UNTUK PARESTESIA ORAL

Introduction: Generally, paresthesia are a pain or uncomfortable sense or abnormality feeling like a burned, sweating, etc. The symptoms can be temporary or permanent, an acute nerve injury will reduce risk of permanent paresthesia. Review: Paresthesia can caused by local anesthesia ( injection method), extraction of third molar, dental implant, endodontic treatment, and trauma. It can prevented by proper patient identification, treatment planning and procedure. The management of paresthesia are observation, Physiologic treatment (cryotherapy, electro-iontophoresis, heat-therapy, massage treatment or acupunture), pharmacology therapy (antibiotics, anti-inflamation, antidepressant, neurotropic group, and topical), phsychologic therapy and laser therapy. Conclusion: Using Laser for paresthesia are to accelerate and enhanced regeneration the nerve tissue. With low-level laser it wiil be e xpected to healing an injured nerve.