Pediatric retroclival hematomas

BACKGROUND

Traumatic retroclival hematomas (RCHs) are infrequent occurrences among the pediatric population. The existing body of research pertaining to these hematomas primarily consists of case reports or small case series, which do not provide adequate guidance for managing this condition.

OBJECTIVE

This study aims to present a report on four cases of RCHs. Additionally, we aim to conduct a systematic review to consolidate the existing literature on pediatric RCHs.

METHODS

The authors conducted a systematic review in accordance with the PRISMA and CARE guidelines. A multivariate logistic regression model was developed to evaluate the potential impact of various clinical variables on clinical outcomes. The study also documented four of our cases, one of which was a rare occurrence of spontaneous subdural RCH.

RESULTS

A total of 62 traumatic RCHs have been documented in the literature. We documented three cases of traumatic RCHs and one case of spontaneous RCH. A systematic analysis of 65 traumatic RCHs was performed. Of trauma cases, 64.6% demonstrated craniocervical junction instability with 83.3% ligamentous involvement. Thirty-five patients were males. 50.7% were aged between 5 and 9 years. Cranial nerve palsies occurred in 29 patients (27 had abducent palsy), 26 of which resolved within 6 months of trauma. 23.5% underwent surgery, and 76.5% were conservatively managed. Surgeries targeted hematomas, hydrocephalus, or craniocervical instability. Approaches to hematomas included transclival and far/extreme lateral suboccipital approaches. Clinical outcome was good in 75.4% and intermediate or poor in 24.6%. Logistic regression suggested an association between craniocervical junction injuries and poor or intermediate outcomes (OR 4.88, 95% CI (1.17, 27.19), p = 0.04).

CONCLUSION

Pediatric RCHs are mostly traumatic and extradural. Children between 5 and 9 years old are most vulnerable. Craniocervical junction injuries, mainly ligamentous, are common in RCHs and are associated with intermediate or poor outcomes. Cervical MRI could be important in cases of trauma to rule out ligamentous injuries of the craniocervical junction. The small size of RCHs should not exempt the careful assessment of craniocervical junction instability. Cranial nerve palsies are common and usually resolve within 6 months. Conservative treatment is typical unless brainstem compression, hydrocephalus, or craniocervical junction instability exists.

[Nerve injuries due to fractures in childhood : Primarily and secondarily on the upper extremity]

The approach for nerve injuries in children in the context of fractures of the upper extremities is inconsistent in the literature. The underlying mostly retrospective studies do not usually consider the potential diagnostics. The frequency of nerve injuries with a clear need for reconstructive surgery is sometimes estimated so differently that precedent-setting errors in these studies must be assumed; however, as 10-20% of pediatric fractures near the elbow show primary or secondary nerve lesions, timely and appropriate further treatment is necessary. An overview concerning diagnostic tools with an explanation of potential results and an algorithm with a timeline for diagnostic and therapeutic management are presented. Good results after nerve lesions can only be achieved when timely diagnostics without delay and correct detection of axonal lesions which benefit from surgical treatment are carried out.

CC Chemokine Family Members' Modulation as a Novel Approach for Treating Central Nervous System and Peripheral Nervous System Injury-A Review of Clinical and Experimental Findings

Despite significant progress in modern medicine and pharmacology, damage to the nervous system with various etiologies still poses a challenge to doctors and scientists. Injuries lead to neuroimmunological changes in the central nervous system (CNS), which may result in both secondary damage and the development of tactile and thermal hypersensitivity. In our review, based on the analysis of many experimental and clinical studies, we indicate that the mechanisms occurring both at the level of the brain after direct damage and at the level of the spinal cord after peripheral nerve damage have a common immunological basis. This suggests that there are opportunities for similar pharmacological therapeutic interventions in the damage of various etiologies. Experimental data indicate that after CNS/PNS damage, the levels of 16 among the 28 CC-family chemokines, i.e., CCL1, CCL2, CCL3, CCL4, CCL5, CCL6, CCL7, CCL8, CCL9, CCL11, CCL12, CCL17, CCL19, CCL20, CCL21, and CCL22, increase in the brain and/or spinal cord and have strong proinflammatory and/or pronociceptive effects. According to the available literature data, further investigation is still needed for understanding the role of the remaining chemokines, especially six of them which were found in humans but not in mice/rats, i.e., CCL13, CCL14, CCL15, CCL16, CCL18, and CCL23. Over the past several years, the results of studies in which available pharmacological tools were used indicated that blocking individual receptors, e.g., CCR1 (J113863 and BX513), CCR2 (RS504393, CCX872, INCB3344, and AZ889), CCR3 (SB328437), CCR4 (C021 and AZD-2098), and CCR5 (maraviroc, AZD-5672, and TAK-220), has beneficial effects after damage to both the CNS and PNS. Recently, experimental data have proved that blockades exerted by double antagonists CCR1/3 (UCB 35625) and CCR2/5 (cenicriviroc) have very good anti-inflammatory and antinociceptive effects. In addition, both single (J113863, RS504393, SB328437, C021, and maraviroc) and dual (cenicriviroc) chemokine receptor antagonists enhanced the analgesic effect of opioid drugs. This review will display the evidence that a multidirectional strategy based on the modulation of neuronal-glial-immune interactions can significantly improve the health of patients after CNS and PNS damage by changing the activity of chemokines belonging to the CC family. Moreover, in the case of pain, the combined administration of such antagonists with opioid drugs could reduce therapeutic doses and minimize the risk of complications.

A Perspective on Hormonal Contraception Usage in Central Nervous System Injury

Naturally occurring life stages in women are associated with changes in the milieu of endogenous ovarian hormones. Women of childbearing age may be exposed to exogenous ovarian hormone(s) because of their use of varying combinations of estrogen and progesterone hormones-containing oral contraceptives (OC; also known as "the pill"). If women have central nervous system (CNS) injury such as spinal cord injury (SCI) and traumatic brain injury (TBI) during their childbearing age, they are likely to retain their reproductive capabilities and may use OC. Many deleterious side effects of long-term OC use have been reported, such as aberrant blood clotting and endothelial dysfunction that consequently increase the risk of myocardial infarction, venous thromboembolism, and ischemic brain injury. Although controversial, studies have suggested that OC use is associated with neuropsychiatric ramifications, including uncontrollable mood swings and poorer cognitive performance. Our understanding about how the combination of endogenous hormones and OC-conferred exogenous hormones affect outcomes after CNS injuries remains limited. Therefore, understanding the impact of OC use on CNS injury outcomes needs further investigation to reveal underlying mechanisms, promote reporting in clinical or epidemiological studies, and raise awareness of possible compounded consequences. The goal of the current review is to discuss the impacts of CNS injury on endogenous ovarian hormones and vice-versa, as well as the putative consequences of exogenous ovarian hormones (OC) on the CNS to identify potential gaps in our knowledge to consider for future laboratory, epidemiological, and clinical studies.

Photobiomodulation and Vascularization in Conduit-Based Peripheral Nerve Repair: A Narrative Review

Background: Peripheral nerve injuries pose a significant clinical issue for patients, especially in the most severe cases wherein complete transection (neurotmesis) results in total loss of sensory/motor function. Nerve guidance conduits (NGCs) are a common treatment option that protects and guides regenerating axons during recovery. However, treatment outcomes remain limited and often fail to achieve full reinnervation, especially in critically sized defects (>3 cm) where a lack of vascularization leads to neural necrosis. Conclusions: A multitreatment approach is, therefore, necessary to improve the efficacy of NGCs. Stimulating angiogenesis within NGCs can help alleviate oxygen deficiency through rapid inosculation with the host vasculature, whereas photobiomodulation therapy (PBMT) has demonstrated beneficial therapeutic effects on regenerating nerve cells and neovascularization. In this review, we discuss the current trends of NGCs, vascularization, and PBMT as treatments for peripheral nerve neurotmesis and highlight the need for a combinatorial approach to improve functional and clinical outcomes.

Exploring altered oscillatory activity in the anterior cingulate cortex after nerve injury: Insights into mechanisms of neuropathic allodynia

While neural oscillations play a critical role in sensory perception, it remains unclear how these rhythms function under conditions of neuropathic allodynia. Recent studies demonstrated that the anterior cingulate cortex (ACC) is associated with the affective-aversive component of pain, and plasticity changes in this region are closely linked to abnormal allodynic sensations. Here, to study the mechanisms of allodynia, we recorded local field potentials (LFPs) in the bilateral ACC of awake-behaving rats and compared the spectral power and center frequency of brain oscillations between healthy and CCI (chronic constriction injury) induced neuropathic pain conditions. Our results indicated that activation of the ACC occurs bilaterally in the presence of neuropathic pain, similar to the healthy condition. Furthermore, CCI affects both spontaneous and stimulus-induced activity of ACC neurons. Specifically, we observed an increase in spontaneous beta activity after nerve injury compared to the healthy condition. By stimulating operated or unoperated paws, we found more intense event-related desynchronization (ERD) responses in the theta, alpha, and beta frequency bands and faster alpha center frequency after CCI compared to before CCI. Although the behavioral manifestation of allodynia was more pronounced in the operated paw than the unoperated paw following CCI, there was no significant difference in the center frequency and ERD responses observed in the ACC between stimulation of the operated and unoperated limbs. Our findings offer evidence supporting the notion that aberrancies in ACC oscillations may contribute to the maintenance and development of neuropathic allodynia.

Nose-to-brain translocation and nervous system injury in response to indium tin oxide nanoparticles of long-term low-dose exposures

Indium tin oxide (ITO) is a semiconductor nanomaterial with broad application in liquid crystal displays, solar cells, and electrochemical immune sensors. It is worth noting that, with the gradual increase in worker exposure opportunities, the exposure risk in occupational production cannot be ignored. At present, the toxicity of ITO mainly focuses on respiratory toxicity. ITO inhaled through the upper respiratory tract can cause pathological changes such as interstitial pneumonia and pulmonary fibrosis. Still, extrapulmonary toxicity after nanoscale ITO nanoparticle (ITO NPs) exposure, such as long-term effects on the central nervous system, should also be of concern. Therefore, we set up exposure dose experiments (0 mg·kg-1, 3.6 mg·kg-1, and 36 mg·kg-1) based on occupational exposure limits to treat C57BL/6 mice via nasal drops for 15 weeks. Moreover, we conducted a preliminary assessment of the neurotoxicity of ITO NPs (20-30 nm) in vivo. The results indicated that ITO NPs can cause diffuse inflammatory infiltrates in brain tissue, increased glial cell responsiveness, abnormal neuronal cell lineage transition, neuronal migration disorders, and neuronal apoptosis related to the oxidative stress induced by ITO NPs exposure. Hence, our findings provide useful information for the fuller risk assessment of ITO NPs after occupational exposure.

The outcome of polyethylene glycol fusion augmented by electrical stimulation in a delayed setting of nerve repair following neurotmesis in a rat model

PURPOSE

Polyethylene glycol is known to improve recovery following its use in repair of acute peripheral nerve injury. The duration till which PEG works remains a subject of intense research. We studied the effect of PEG with augmentation of 20Htz of electrical stimulation (ES) following neurorrhaphy at 48 h in a rodent sciatic nerve neurotmesis model.

METHOD

Twenty-four Sprague Dawley rats were divided into 4 groups. In group I, the sciatic nerve was transected and repaired immediately. In group II, PEG fusion was done additionally after acute repair. In group III, repair and PEG fusion were done at 48 h. In group IV, ES of 20Htz at 2 mA for 1 h was added to the steps followed for group III. Weekly assessment of sciatic functional index (SFI), pinprick, and cold allodynia tests were done at 3 weeks and euthanized. Sciatic nerve axonal count and muscle weight were done.

RESULTS

Groups II, III, and IV showed significantly better recovery of SFI (II: 70.10 ± 1.24/III: 84.00 ± 2.59/IV: 74.40 ± 1.71 vs I: 90.00 ± 1.38) (p < 0.001) and axonal counts (II: 4040 ± 270/III: 2121 ± 450/IV:2380 ± 158 vs I: 1024 ± 094) (p < 0.001) at 3 weeks. The experimental groups showed earlier recovery of sensation in comparison to the controls as demonstrated by pinprick and cold allodynia tests and improved muscle weights. Addition of electrical stimulation helped in better score with SFI (III: 84.00 ± 2.59 vs IV: 74.40 ± 1.71) (p < 0.001) and muscle weight (plantar flexors) (III: 0.49 ± 0.02 vs IV: 0.55 ± 0.01) (p < 0.001) in delayed repair and PEG fusions.

CONCLUSION

This study shows that PEG fusion of peripheral nerve repair in augmentation with ES results in better outcomes, and this benefit can be demonstrated up to a window period of 48 h after injury.

Serum Angiopoietin-2 level increase differs between polytraumatized patients with and without central nervous system injuries

Since endothelial cells rapidly release Angiopoietin-2 (Ang-2) in response to vascular injury and inflammatory stimuli, we aimed to investigate if its serum levels increase in polytraumatized patients. Our cohort study evaluated 28 blunt polytrauma survivors (mean age, 38.4 years; median ISS, 34) who were directly admitted to our level I trauma center in 2018. We assessed the serum Ang-2 level at admission and on days 1, 3, 5, 7, and 10 during hospitalization. Ang-2 was released into the circulation immediately after polytrauma. At admission (day 0), it amounted to 8286 ± 5068 pg/mL, three-and-a-half times the reference value of 2337 ± 650 pg/mL assessed in a healthy control group. Subgroup analysis provided a higher mean Ang-2 level in the CNSI group combining all patients suffering a brain or spinal cord injury compared to the non-CNSI group solely on day 0 [11083 ± 5408 pg/mL versus 3963 ± 2062 pg/mL; p < 0.001]. Whereas the mean Ang-2 level increased only in the non-CNSI group from day 0 to day 3 (p = 0.009), the respective curves showed similar continuous decreases starting with day 3. Multivariate logistic regression analysis revealed an association between the Ang-2 day 0 level and the presence of a CNSI (OR = 1.885; p = 0.048). ROC analysis provided a cutoff level of 5352 pg/mL. In our study group, serum Ang-2 levels assessed at admission differed between polytraumatized patients with and without brain or spinal cord injuries. Based on our findings, we consider serum Ang-2 levels an effective biomarker candidate for indicating CNSI in these patients at admission, worthy of further evaluation in large multicenter studies.

A historical delve into neurotrauma-focused critical care

Neurocritical care is a multidisciplinary field managing patients with a wide range of aliments. Specifically, neurotrauma is a rapidly growing field with increasing demands. The history of how neurotrauma management came to its current form has not been extensively explored before. Our review delves into the history, timeline, and noteworthy pioneers of neurotrauma-focused neurocritical care. We explore the historical development during early times, the 18th-20th centuries, and modern times, as well as warfare- and sports-related concussions. Research is ever growing in this budding field, with several promising innovations on the horizon.

Caveolin-1 scaffolding domain peptide prevents corpus cavernosum fibrosis and erectile dysfunction in bilateral cavernous nerve injury-induced rats

BACKGROUND

Corpus cavernosum (CC) fibrosis significantly contributes to post-radical prostatectomy erectile dysfunction (pRP-ED). Caveolin-1 scaffolding domain (CSD)-derived peptide has gained significant concern as a potent antagonist of tissue fibrosis. However, applying CSD peptide on bilateral cavernous nerve injury (BCNI)-induced rats remains uninvestigated.

AIM

The aim was to explore the therapeutic outcome and underlying mechanism of CSD peptide for preventing ED in BCNI rats according to the hypothesis that CSD peptide may exert beneficial effects on erectile tissue and function following BCNI through limiting collagen synthesis in CC smooth muscle cells (CCSMCs) and CC fibrosis.

METHODS

After completing a random assignment of male Sprague Dawley rats (10 weeks of age), BCNI rats received either saline or CSD peptide treatment, as opposed to sham-operated rats. The evaluations of erectile function (EF) and succedent collection and histological and molecular biological examinations of penile tissue were accomplished 3 weeks postoperatively. In addition, the fibrotic model of CCSMCs was used to further explore the mechanism of CSD peptide action in vitro.

OUTCOMES

The assessments of EF, SMC/collagen ratio, α-smooth muscle actin, caveolin-1 (CAV1), and profibrotic indicators expressions were conducted.

RESULTS

BCNI rats exhibited significant decreases in EF, SMC/collagen ratio, α-SMA, and CAV1 levels, and increases in collagen content together with transforming growth factor (TGF)-β1/Smad2 activity. However, impaired EF, activated CC fibrosis, and Smad2 signaling were attenuated after 3 weeks of CSD peptide treatment in BCNI rats. In vitro, TGF-β1-induced CCSMCs underwent fibrogenetic transformation characterized by lower expression of CAV1, higher collagen composition, and phosphorylation of Smad2; then, the delivery of CSD peptide could significantly block CCSMC fibrosis by inactivating Smad2 signaling.

CLINICAL IMPLICATIONS

Based on available evidence of CSD peptide in the prevention of ED in BCNI rats, this study can aid in the development and clinical application of CSD peptide targeting pRP-ED.

STRENGTHS AND LIMITATIONS

This study provides data to suggest that CSD peptide protects against BCNI-induced deleterious alterations in EF and CC tissues. However, the available evidence still does not fully clarify the detailed mechanism of action of CSD peptide.

CONCLUSION

Administration of CSD peptide significantly retarded collagen synthesis in CCSMCs, limited CC fibrosis, and prevented ED via confrontation of TGF-β1/Smad signaling in BCNI rats.

Elemental Mapping in a Preclinical Animal Model Reveals White Matter Copper Elevation in the Acute Phase of Central Nervous System Trauma

Understanding the chemical events following trauma to the central nervous system could assist in identifying causative mechanisms and potential interventions to protect neural tissue. Here, we apply a partial optic nerve transection model of injury in rats and use synchrotron X-ray fluorescence microscopy (XFM) to perform elemental mapping of metals (K, Ca, Fe, Cu, Zn) and other related elements (P, S, Cl) in white matter tracts. The partial optic nerve injury model and spatial precision of microscopy allow us to obtain previously unattained resolution in mapping elemental changes in response to a primary injury and subsequent secondary effects. We observed significant elevation of Cu levels at multiple time points following the injury, both at the primary injury site and in neural tissue near the injury site vulnerable to secondary damage, as well as significant changes in Cl, K, P, S, and Ca. Our results suggest widespread metal dyshomeostasis in response to central nervous system trauma and that altered Cu homeostasis may be a specific secondary event in response to white matter injury. The findings highlight metal homeostasis as a potential point of intervention in limiting damage following nervous system injury.

Neat1 lncRNA organizes the inflammatory gene expressions in the dorsal root ganglion in neuropathic pain caused by nerve injury

Primary sensory neurons regulate inflammatory processes in innervated regions through neuro-immune communication. However, how their immune-modulating functions are regulated in concert remains largely unknown. Here, we show that Neat1 long non-coding RNA (lncRNA) organizes the proinflammatory gene expressions in the dorsal root ganglion (DRG) in chronic intractable neuropathic pain in rats. Neat1 was abundantly expressed in the DRG and was upregulated after peripheral nerve injury. Neat1 overexpression in primary sensory neurons caused mechanical and thermal hypersensitivity, whereas its knockdown alleviated neuropathic pain. Bioinformatics analysis of comprehensive transcriptome changes indicated the inflammatory response was the most relevant function of genes upregulated through Neat1. Consistent with this, upregulation of proinflammatory genes in the DRG following nerve injury was suppressed by Neat1 knockdown. Expression changes of these proinflammatory genes were regulated through Neat1-mRNA interaction-dependent and -independent mechanisms. Notably, Neat1 increased proinflammatory genes by stabilizing its interacting mRNAs in neuropathic pain. Finally, Neat1 in primary sensory neurons contributed to spinal inflammatory processes that mediated peripheral neuropathic pain. These findings demonstrate that Neat1 lncRNA is a key regulator of neuro-immune communication in neuropathic pain.

Advances in Nerve Injury Models on a Chip

Regeneration and functional recovery of the damaged nerve are challenging due to the need for effective therapeutic drugs, biomaterials, and approaches. The poor outcome of the treatment of nerve injury stems from the incomplete understanding of axonal biology and interactions between neurons and the surrounding environment, such as glial cells and extracellular matrix. Microfluidic devices, in combination with various injury techniques, have been applied to test biological hypotheses in nerve injury and nerve regeneration. The microfluidic devices provide multiple advantages over the in vitro cell culture on a petri dish and in vivo animal models because a specific part of the neuronal environment can be manipulated using physical and chemical interventions. In addition, single-cell behavior and interactions between neurons and glial cells can be visualized and quantified on microfluidic platforms. In this article, current in vitro nerve injury models on a chip that mimics in vivo axonal injuries and the regeneration process of axons are summarized. The microfluidic-based nerve injury models could enhance the understanding of the physiological and pathophysiological mechanisms of nerve tissues and simultaneously serve as powerful drug and biomaterial screening platforms.

The Risk of Nerve Injury in Pediatric Forearm Fractures

UPDATE

This article was updated on July 19, 2023, because of a previous error, which was discovered after the preliminary version of the article was posted online. On page 1080, in the last sentence of the Results section of the Abstract, the text that had read "0.05% (4 of 777)" now reads "0.5% (4 of 777)."

BACKGROUND

The risk of fracture-related nerve injury associated with forearm fractures in children is unknown. The purposes of the present study were to calculate the risk of fracture-related nerve injury and to report the institutional rate of complications of surgical treatment of pediatric forearm fractures.

METHODS

Four thousand, eight hundred and sixty-eight forearm fractures (ICD-10 codes S52.0 to S52.7) that had been treated in our tertiary level pediatric hospital between 2014 and 2021 were identified in our institutional fracture registry. Of these, 3,029 fractures occurred in boys and 53 were open fractures. Sex, age at injury, trauma mechanism and energy, fracture type, treatment method, and cause and type of nerve injury were assessed in 43 patients with 44 registered nerve injuries. Patients with nerve injuries were reevaluated to calculate the recovery time. Univariable and multivariable regression analyses were performed to determine the risk of nerve injury.

RESULTS

The risk of a fracture-related nerve injury was 0.7% (33 of 4,868). Only 2 injuries were permanent; thus, the risk of permanent nerve injury associated with a forearm fracture was 0.04% (2 of 4,868). The ulnar nerve was affected in 19 cases; the median nerve, in 8; and the radial nerve, in 7. In cases of open fracture, the risk of nerve injury was 17% (9 of 53). Open fractures had an OR of 33.73 (95% CI, 14.97 to 70.68) on univariate analysis and an OR of 10.73 (95% CI 4.50 to 24.22) on multivariate analysis with adjustment for female sex and both-bone diaphyseal fracture. Both-bone diaphyseal fracture (ICD-10 code S52.4) had an OR of 9.01 (95% CI, 4.86 to 17.37) on univariate analysis and an OR of 9.98 (95% CI 5.32 to 19.47) on multivariate analysis with adjustment for age and female sex. Overall, 777 fractures were internally fixed. The risk of nerve injury as a complication of internal fixation was 1.3% (10 of 777). Four of these iatrogenic injuries (including 2 involving the median nerve, 1 involving the ulnar nerve, and 1 involving the radial nerve) were permanent; thus, the risk of permanent nerve injury as a complication of internal fixation was 0.5% (4 of 777).

CONCLUSIONS

Nerve injury following a pediatric forearm fracture is rare and has an excellent potential for spontaneous recovery. In the present study, all of the permanent nerve injuries occurred in association with open fractures or as a complication of internal fixation.

LEVEL OF EVIDENCE

Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.

MR documented craniocervical ligamentous injury at age 18 months: delayed formation of OS odontoideum. Complex management issues. Case-based review

OBJECTIVE

There are two separate theories regarding the genesis of os odontoideum: congenital and post-traumatic. Trauma documentation in the past has been the presence of a normal odontoid process at the time of initial childhood injury and subsequent development of the os odontoideum. True MR documentation of craniocervical injury in early childhood and subsequent os odontoideum formation has been very rare.

METHODS

An 18-month-old sustained craniocervical ligamentous injury documented on MRI with transient neurological deficit. Chiari I abnormality was also recorded. Subsequent serial imaging of craniocervical region showed the formation of os odontoideum and instability. He became symptomatic from the os odontoideum and the Chiari I abnormality. The patient underwent decompression and intradural procedure for Chiari I abnormality and occipitocervical fusion. Postoperative course was complicated by the failure of fusion and redo. He later required transoral ventral medullary decompression. He recovered.

RESULTS

This is an MR documented craniocervical ligamentous injury with sequential formation of os odontoideum with accompanying changes in the atlas. Despite a subsequent successful dorsal occipitocervical fusion, he became symptomatic requiring transoral decompression.

CONCLUSIONS

Os odontoideum here is recognized as a traumatic origin with the presence of congenital Chiari I abnormality as a separate entity. The changes of the anterior arch of C1 as well as the os formation were serially documented and give credence to blood supply changes in the os and atlas as a result of the trauma. The recognized treatment of dorsal occipitocervical fusion failed in this case requiring also a ventral decompression of the medulla.

Cutaneous Injection of Resiniferatoxin Completely Alleviates and Prevents Nerve-Injury-Induced Neuropathic Pain

Fifth lumbar (L5) nerve injury in rodent produces neuropathic manifestations in the corresponding hind paw. The aim of this study was to investigate the effect of cutaneous injection of resiniferatoxin (RTX), a TRPV1 receptor agonist, in the rat's hind paw on the neuropathic pain induced by L5 nerve injury. The results showed that intraplantar injection of RTX (0.002%, 100 µL) (1) completely reversed the development of chronic thermal and mechanical hypersensitivity; (2) completely prevented the development of nerve-injury-induced thermal and mechanical hypersensitivity when applied one week earlier; (3) caused downregulation of nociceptive pain markers, including TRPV1, IB4 and CGRP, and upregulation of VIP in the ipsilateral dorsal horn of spinal cord and dorsal root ganglion (DRG) immunohistochemically and a significant reduction in the expression of TRPV1 mRNA and protein in the ipsilateral DRG using Western blot and qRT-PCR techniques; (4) caused downregulation of PGP 9.5- and CGRP-immunoreactivity in the injected skin; (5) produced significant suppression of c-fos expression, as a neuronal activity marker, in the spinal neurons in response to a second intraplantar RTX injection two weeks later. This work identifies the ability of cutaneous injection of RTX to completely alleviate and prevent the development of different types of neuropathic pain in animals and humans.

miR-124: A Promising Therapeutic Target for Central Nervous System Injuries and Diseases

Central nervous system injuries and diseases, such as ischemic stroke, spinal cord injury, neurodegenerative diseases, glioblastoma, multiple sclerosis, and the resulting neuroinflammation often lead to death or long-term disability. MicroRNAs are small, non-coding, single-stranded RNAs that regulate posttranscriptional gene expression in both physiological and pathological cellular processes, including central nervous system injuries and disorders. Studies on miR-124, one of the most abundant microRNAs in the central nervous system, have shown that its dysregulation is related to the occurrence and development of pathology within the central nervous system. Herein, we review the molecular regulatory functions, underlying mechanisms, and effective delivery methods of miR-124 in the central nervous system, where it is involved in pathological conditions. The review also provides novel insights into the therapeutic target potential of miR-124 in the treatment of human central nervous system injuries or diseases.

Inhibition of the RNA Regulator HuR by SRI-42127 Attenuates Neuropathic Pain After Nerve Injury Through Suppression of Neuroinflammatory Responses

Microglial activation with the production of pro-inflammatory mediators such as IL-6, TNF-α, and IL-1β, is a major driver of neuropathic pain (NP) following peripheral nerve injury. We have previously shown that the RNA binding protein, HuR, is a positive node of regulation for many of these inflammatory mediators in glia and that its chemical inhibition or genetic deletion attenuates their production. In this report, we show that systemic administration of SRI-42127, a novel small molecule HuR inhibitor, attenuates mechanical allodynia, a hallmark of NP, in the early and chronic phases after spared nerve injury in male and female mice. Flow cytometry of lumbar spinal cords in SRI-42127-treated mice shows a reduction in infiltrating macrophages and a concomitant decrease in microglial populations expressing IL-6, TNF-α, IL-1β, and CCL2. Immunohistochemistry, ELISA, and qPCR of lumbar spinal cord tissue indicate suppression of these cytokines and other inflammatory mediators. ELISA of plasma samples in the acute phase also shows attenuation of inflammatory responses. In summary, inhibition of HuR by SRI-42127 leads to the suppression of neuroinflammatory responses and allodynia after nerve injury and represents a promising new direction in the treatment of NP.

Bilirubin-Induced Neurological Damage: Current and Emerging iPSC-Derived Brain Organoid Models

Bilirubin-induced neurological damage (BIND) has been a subject of studies for decades, yet the molecular mechanisms at the core of this damage remain largely unknown. Throughout the years, many in vivo chronic bilirubin encephalopathy models, such as the Gunn rat and transgenic mice, have further elucidated the molecular basis of bilirubin neurotoxicity as well as the correlations between high levels of unconjugated bilirubin (UCB) and brain damage. Regardless of being invaluable, these models cannot accurately recapitulate the human brain and liver system; therefore, establishing a physiologically recapitulating in vitro model has become a prerequisite to unveil the breadth of complexities that accompany the detrimental effects of UCB on the liver and developing human brain. Stem-cell-derived 3D brain organoid models offer a promising platform as they bear more resemblance to the human brain system compared to existing models. This review provides an explicit picture of the current state of the art, advancements, and challenges faced by the various models as well as the possibilities of using stem-cell-derived 3D organoids as an efficient tool to be included in research, drug screening, and therapeutic strategies for future clinical applications.

Restorative therapy using microglial depletion and repopulation for central nervous system injuries and diseases

Microglia are important resident immune cells in the central nervous system (CNS) and play an important role in its development, homeostasis, and disease treatments. Activated microglia perform diverse functions in mouse models of CNS neurodegenerative diseases or deficits. In humans, microglia have been linked to various neurodegenerative diseases. Following brain or spinal cord injury, microglia express pro- and anti-inflammatory phenotypes at different stages of recovery. With the development of pharmacological and genetic tools for microglial depletion, studies have demonstrated that microglial depletion exerts both positive and negative effects in the treatment of CNS diseases. Notably, microglial depletion provides an empty niche that stimulates production of new microglia. Microglial depletion and repopulation can not only treat diseases by eliminating dysfunctional microglia but can also provide an indication of the molecular mechanisms of diseases. Although this approach has shown impressive results, its use is still in its infancy. In this review, we summarize the current pharmacological and genetic tools for microglial depletion and highlight recent advances in microglial repopulation therapy for the treatment and functional recovery of neurological diseases and deficits. Finally, we briefly discuss the therapeutic challenges and prospective uses of microglial repopulation therapy.

Regenerative Role of T Cells in Nerve Repair and Functional Recovery

The immune system is essential in the process of nerve repair after injury. Successful modulation of the immune response is regarded as an effective approach to improving treatment outcomes. T cells play an important role in the immune response of the nervous system, and their beneficial roles in promoting regeneration have been increasingly recognized. However, the diversity of T-cell subsets also delivers both neuroprotective and neurodegenerative functions. Therefore, this review mainly discusses the beneficial impact of T-cell subsets in the repair of both peripheral nervous system and central nervous system injuries and introduces studies on various therapies based on T-cell regulation. Further discoveries in T-cell mechanisms and multifunctional biomaterials will provide novel strategies for nerve regeneration.

Effect of delayed photobiomodulation therapy on neurosensory recovery in patients with mandibular nerve neurotmesis following traumatic mandibular fracture: A randomized triple-blinded clinical trial

INTRODUCTION

There is a possibility of neurotmesis of the inferior alveolar nerve (IAN) in mandibular fractures, which leads to neurosensory impairment. In this study, we aimed to investigate the efficacy of photobiomodulation therapy (PBMT) in patients with neurotmesis following trauma and mandibular fracture.

MATERIALS AND METHODS

This triple-blind randomized trial was carried out on patients who suffered neurotmesis of the IAN following mandibular angle and body fracture at least for 6 months. In the intervention group, laser irradiation was applied with a low-level GaAlAs diode laser (continuous wave of 810 nm wavelength, power of 200 mW, and energy density of 12-14 J/cm²). In the control group, the laser probe was turned off and placed on the affected area. LLLT was done for 12 sessions (2 times/week for 6 weeks). Light touch sensations, two-point discrimination, thermal discrimination (cold and warm stimulus), electric pulp test (EPT), and oral health impact profile (OHIP)-14 questionnaire were performed before the intervention, immediately after each PBMT session, and after 3, 6, 9 and 12 months.

RESULTS

In both groups, 3 and 23 patients were female and male, respectively. The results showed significantly improved light (cotton swab), light (wooden cotton swab), and sharp (dental needle) touch sensations, and two-point discrimination test in the PBMT group after the 10th, 11th, 10th, and 10th session, respectively. Two-way repeated measure ANOVA revealed that the trend of light touch sensation with cotton swab and two-point discrimination test was statistically significant (p-value = 0.002 and 0.001, respectively). The results of OHIP-14 test showed a significantly higher mean in the PBMT group 3 months after PBMT. There was no statistically significant difference in EPT and thermal discrimination tests regarding the patients' group.

CONCLUSION

PBMT could be an effective treatment for late post-traumatic nerve neurotmesis following a traumatic mandibular fracture.

The Potential Benefits of Dietary Polyphenols for Peripheral Nerve Regeneration

Peripheral nerves are frequently affected by lesions caused by trauma (work accidents, car incidents, combat injuries) and following surgical procedures (for instance cancer resection), resulting in loss of motor and sensory function with lifelong impairments. Irrespective of the intrinsic capability of the peripheral nervous system for regeneration, spontaneous or surgically supported regeneration is often unsatisfactory with the limited functional success of nerve repair. For this reason, many efforts have been made to improve the regeneration process. Beyond innovative microsurgical methods that, in certain cases, are necessary to repair nerve injuries, different nonsurgical treatment approaches and adjunctive therapies have been investigated to enhance nerve regeneration. One possibility could be taking advantage of a healthy diet or lifestyle and their relation with proper body functions. Over the years, scientific evidence has been obtained on the benefits of the intake of polyphenols or polyphenol-rich foods in humans, highlighting the neuroprotective effects of these compounds in many neurodegenerative diseases. In order to improve the available knowledge about the potential beneficial role of polyphenols in the process of peripheral nerve regeneration, this review assessed the biological effects of polyphenol administration in supporting and promoting the regenerative process after peripheral nerve injury.

Autonomous electrochemical biosensing of glial fibrillary acidic protein for point-of-care detection of central nervous system injuries

The integration of electrochemical biosensors into fluid handling units such as paper-based, centrifugal, and capillary microfluidic devices has been explored with the purpose of developing point-of-care platforms for quantitative detection of bodily fluid markers. However, the present fluidic device designs largely lack the capacity of full assay automation, needing manual loading of one or multiple reagents or requiring external devices for liquid manipulation. Such fluidic handing platforms also require universality for detecting various biomarkers. These platforms are also largely produced using materials unsuitable for scalable manufacturing and with a high production cost. The mechanism of fluid flow also often induces noise to the embedded biosensors which adversely impacts the accuracy of biosensing. This work addresses these challenges by presenting a reliable design of a fully automated and universal capillary-driven microfluidic platform that automates several steps of label-free electrochemical biosensing assays. These steps include sample aliquoting, controlled incubation, removal of non-specific bindings, reagent mixing and delivery to sensing electrodes, and electrochemical detection. The multilayer architecture of the microfluidic device is made of polymeric and adhesive materials commercially used for the fabrication of point-of-care devices. The design and geometry of different components of the device (e.g., sampling unit, mixer, resistances, delay valves, interconnecting components) were optimized using a combined experimental testing and numerical fluid flow modeling to reach high reproducibility and minimize the noise-induced to the biosensor. As a proof of concept, the performance of this on-chip immunosensing platform was demonstrated for rapid and autonomous detection of glial fibrillary acidic proteins (GFAP) in phosphate-buffered saline (PBS). The microfluidic immunosensing device exhibited a linear detection range of 10-1000 pg mL^-1 for the detection of GFAP within 30 min, with a limit of detection (LoD) and sensitivity of 3 pg mL^-1 and 39 mL pg^-1 mm^-2 in PBS, respectively. Owing to its simplicity, sample-to-result performance, universality for handing different biofluids, low cost, high reproducibility, compatibility with scalable production, and short analysis time, the proposed biosensing platform can be further adapted for the detection of other biomarkers in different clinical bodily fluids for rapid diagnostic and prognostic applications.

Epidemiology of Spine-Related Neurologic Injuries in Professional Baseball Players

STUDY DESIGN

A retrospective case series study.

OBJECTIVE

To analyze the epidemiology of diagnoses of degenerative cervical and lumbar spinal conditions among Major League Baseball (MLB) and Minor League Baseball (MiLB) players.

SUMMARY OF BACKGROUND DATA

Repetitive high-energy forces in professional baseball players may predispose them to degenerative cervical and lumbar spinal conditions. There is a lack of data concerning the epidemiology of these injuries in professional baseball.

METHODS

Deidentified data on spine injuries were collected from all MLB and MiLB teams from 2011 to 2016 from the MLB-commissioned Health and Injury Tracking System database. Rates of diagnoses of common degenerative spinal conditions as well as their impact on days missed due to injury, necessitation of surgery, and player participation and career-ending status were assessed. Injury rates were reported as injuries per 1000 athlete-exposures in concordance with prior studies.

RESULTS

Over 2011 to 2016, 4246 days of play were missed due to 172 spine-related injuries. 73.3% were related to the lumbar spine and 26.7% to the cervical spine. There were similar rates of surgery required for these injuries (18.3% of lumbar injuries vs. 13.0% of cervical injuries, P = 0.2164). Mean age of players with cervical injuries was higher compared with the lumbar group (27.5 vs. 25.4, P = 0.0119). Average number of days missed due to lumbar injuries was significantly higher than those due to cervical injuries (34.1 vs. 21.6 d, P = 0.0468). Spine injury rates for pitchers were significantly higher than those of other position players (0.086 per 1000 athlete-exposures vs. 0.037, P < 0.0001).

CONCLUSION

Neurologic diagnoses relating to the cervical and lumbar spine lead to substantial disability among MLB and MiLB players as well as days missed from play. Pitchers have over double the rates of injury compared with other position players. Lumbar conditions were associated with significantly higher numbers of days missed from play.Level of Evidence: 4.

Gunshot-related lower extremity nerve injuries

OBJECTIVE

The purpose of this study was to describe the frequency of nerve injury associated with lower extremity ballistic trauma, the associated skeletal and soft tissue injuries, and the rate of neurologic recovery.

DESIGN AND SETTING

A retrospective review of an institutional trauma database was completed at a single level 1 trauma academic medical center.

PATIENTS

This was an institutional review board approved retrospective cohort study of patients over 16 years of age presenting with ballistic-related traumatic injury to the lower extremities between May 2018 and May 2019. All patients identified with lower extremity ballistic trauma were included in this study. The rate of nerve palsy, associated skeletal injury, and operative fixation were recorded for each anatomic zone. Rates of associated concomitant vascular injury, fracture, and compartment syndrome were collected through a review of the electronic medical records. Chart review was performed to evaluate outcomes and nerve recovery.

RESULTS

Twenty-one patients (21 extremities, 21/148, 14%) were diagnosed by attending physicians, fellowship-trained in orthopedic trauma, as having ballistic-related nerve injuries. Seventy-three percent of patients with a documented neurologic injury (11/15) demonstrated complete nerve recovery as measured by the MRC and sensory scale assessment at most recent follow-up, while the rest demonstrated no improvement in their neurologic deficits from presentation. The rate of associated vascular injury in patients with lower extremity nerve palsies was 38% (8/21). While the rate of vascular injury in the absence of neurologic injury was 3% (4/127).

CONCLUSIONS

This series of lower extremity nerve injuries in a large sample of urban lower extremity ballistic trauma noted a high rate of concomitant nerve injuries. An associated diagnosis of a vascular injury appears to portend a higher risk of neurologic injury. Treating surgeons should have a high index of suspicion for associated vascular injury in patients presenting with a ballistic lower extremity nerve palsy.

Transglutaminase 2 as a therapeutic target for neurological conditions

INTRODUCTION

Transglutaminase 2 (TG2) has been implicated in numerous neurological conditions, including neurodegenerative diseases, multiple sclerosis, and CNS injury. Early studies on the role of TG2 in neurodegenerative conditions focused on its ability to 'crosslink' proteins into insoluble aggregates. However, more recent studies have suggested that this is unlikely to be the primary mechanism by which TG2 contributes to the pathogenic processes. Although the specific mechanisms by which TG2 is involved in neurological conditions have not been clearly defined, TG2 regulates numerous cellular processes through which it could contribute to a specific disease. Given the fact that TG2 is a stress-induced gene and elevated in disease or injury conditions, TG2 inhibitors may be useful neurotherapeutics.

AREAS COVERED

Overview of TG2 and different TG2 inhibitors. A brief review of TG2 in neurodegenerative diseases, multiple sclerosis and CNS injury and inhibitors that have been tested in different models. Database search: https://pubmed.ncbi.nlm.nih.gov prior to 1 July 2021.

EXPERT OPINION

Currently, it appears unlikely that inhibiting TG2 in the context of neurodegenerative diseases would be therapeutically advantageous. However, for multiple sclerosis and CNS injuries, TG2 inhibitors may have the potential to be therapeutically useful and thus there is rationale for their further development.

Effects of Photobiomodulation Therapy (LED 630 nm) on Muscle and Nerve Histomorphometry after Axonotmesis

Peripheral injuries constitute a substantial clinical problem with unsatisfactory treatment. The study's objective was to analyze the effects of photobiomodulation therapy (PBMT) on median nerve regeneration and muscle recovery after axonotmesis. Twenty-four rats were randomized into three groups: control (CG), injury (IG), and LED therapy (LEDG). A 630 ± 20 nm (300-mW) LED was placed in contact with the skin. One point over the injury site was irradiated for 30 s, delivering 9 J (9 J cm-2 ). PBMT irradiation was performed once daily for 5 days followed by two-day interval and then more five consecutive days of treatment. Proximal and distal segments of the nerve and flexors muscles were removed for histomorphometric analysis using H&E staining for muscles and osmium tetroxide for nerves. The myelinated fiber and axon diameter and the myelin sheath thickness were greater in the proximal and distal nerve segments in the LEDG compared to the IG (P ≤ 0.05). The number of myelinated fibers was greater in the distal segment of the LEDG (P ≤ 0.05). The area, circumference, and diameter of the muscle fibers were larger in the LEDG than in the IG (P ≤ 0.05). The PBMT protocol used favored axonal regeneration and muscle recovery.

Sjögren's syndrome with nervous system injury combined with pulmonary and osseous cryptococcosis: a case report

BACKGROUND

Sjögren's syndrome is a common autoimmune disease that can involve the nervous system, but rarely both the central and peripheral. Long-term use of high-dose corticosteroids and immunosuppressants are the main risk factors for Cryptococcus infection in patients with Sjögren's syndrome, of which pulmonary infection is the most common, while multiple bone infections are rare.

CASE PRESENTATION

A 46-year-old Chinese woman with a 2-year history of Sjögren's syndrome presented to our hospital with numbness of limbs, shortness of breath, and weakness. Blood immunochemistry showed that antinuclear antibody (1:640), anti-Sjögren's syndrome-A antibodies, and anti-centromere antibodies were strongly positive. Cranial magnetic resonance imaging revealed multiple demyelinating lesions in the white matter of bilateral cerebral hemispheres. Electromyography indicated serious peripheral nerve injury, especially in lower limbs. Computed tomography scan of lumbar vertebral displayed multiple high-density shadows, and the corresponding vertebrae on magnetic resonance imaging showed abnormal low signal intensity on T1 and T2 sequences. Positron emission tomography-computed tomography showed multiple lesions with high 18F-fluorodeoxyglucose uptake in lung and vertebral bodies. Both lung and bone biopsies suggested Cryptococcus infection, with the diagnosis of Sjögren's syndrome with nervous system injury combined pulmonary and osseous cryptococcosis. She took a reduced dose of prednisone about 10 mg/day, terminated mycophenolate mofetil, and began to take immunoglobulin of 0.4 g/kg/day intravenously for 5 days, fluconazole (400 mg/day) for 6 months. Within 3 weeks, her chest radiography showed a marked improvement, and 3 months later, the pulmonary lesions disappeared on her computed tomography scan.

CONCLUSIONS

This case exhibits an extremely rare condition of neural involvement in Sjögren's syndrome combined with pulmonary and osseous cryptococcosis. This report also highlights the crucial role of detailed clinical examination, serologic markers, and biopsy in avoiding misdiagnosis. Currently, there is no guideline for this situation; in this case, we controlled the disease successfully with antifungal drugs and adequate gamma globulin, followed by an appropriate dose of corticosteroids.

Recovery of Motor Nerve Injuries Associated With Displaced, Extension-type Pediatric Supracondylar Humerus Fractures

BACKGROUND

Nerve injuries occur in approximately 11% of pediatric extension supracondylar humerus fractures (SCHF), yet there is scarce literature to guide clinicians on management. The primary goal of this study was to report the presentation, treatment, and outcome of motor nerve injuries associated with extension SCHF. Our secondary goal was to determine which injury and treatment factors were associated with prolonged motor nerve recovery.

METHODS

Two hundred forty-four traumatic nerve injuries associated with extension SCHF treated at a single institution between 1996 and 2012 were reviewed. Patients with iatrogenic nerve injuries or subjective paresthesias without motor deficit were excluded. Univariable and multivariable general linear modeling were used to compare recovery times across nerve injury types and to determine the effect of injury and treatment characteristics on recovery time.

RESULTS

Patients were a mean age of 6.7 years, with 89% presenting with a single nerve injury and 29% of the cohort experiencing a concurrent vascular injury. The majority of injuries (62%) were to the median nerve. Forty-three (18%) cases had acute nerve decompression at the time of fracture fixation. Five cases required subsequent surgery for poor nerve recovery; none of which underwent initial nerve decompression. Thirty-one patients were lost to follow-up after injury. Median time to nerve recovery was 2.3 months (IQR 1.4 to 3.7 mo); 60% of injuries had nerve recovery by 3 months and 196 (92%) patients had complete nerve recovery at final follow-up. A greater percentage of isolated median nerve (70%) injuries recovered within 3 months compared with radial nerve (42%) injuries (P=0.01). Multivariable analysis demonstrated that multiple nerve injuries took 54% longer to recover than single median nerve injuries (P=0.01), and single radial nerve injuries took 30% longer to recover than single median nerve injuries (P=0.04).

CONCLUSIONS

The majority of nerve injuries associated with pediatric extension SCHF recover within 6 months without acute nerve decompression. The presence of either an isolated radial nerve injury or multiple nerve injuries is associated with prolonged motor recovery.

LEVEL OF EVIDENCE

Level IV.

[REPAIR OF ACUTE CLOSED ACHILLES TENDON RUPTURES BY CHANNEL-ASSISTED MINIMALLY INVASIVE REPAIR SYSTEM]

OBJECTIVE

To evaluate the effectiveness of channel-assisted minimally invasive repair (CAMIR) for acute closed Achilles tendon ruptures.

METHODS

Between January 2011 and June 2012, 30 patients (30 sides) with acute closed Achilles tendon ruptures were treated with CAMIR technique. Among 30 patients, 18 were male and 12 were female with an average age of 30.4 years (range, 22-50 years); the locations were left side in 10 cases and right side in 20 cases. All the causes were sports injury. B-ultrasound was used to confirm the diagnosis, with the average distance from the rupture site to the Achilles tendon insertion of 4.4 cm (range, 2-8 cm). The time from injury to operation was 3 hours to 9 days (median, 4 days). All injuries were repaired by CAMIR technique.

RESULTS

The average operation time was 17.0 minutes (range, 10-25 minutes), and the mean incision length was 2.0 cm (range, 1.5-2.5 cm). All the incisions healed by first intention. There was no complication of wound problem, deep vein thrombosis, re-rupture, or sural nerve injury. All cases were followed up 12-24 months with an average of 16 months. At last follow-up, the patients could walk normally with powerful raising heels and restored to normal activity level. MRI imaging suggested the continuity and healing of ruptured tendon. The circumference difference between affected leg and normal leg was less than 1 cm, and the ankle dorsi-extension was 20-30°, plantar flexion was 20-30°. Arner Lindholm score showed that the surgical results were excellent in 28 cases and good in 2 cases, with an excellent and good rate of 100%.

CONCLUSION

CAMIR is a safe and reliable method to repair acute closed Achilles tendon rupture, with many advantages of minimal injury, low re-rupture and infection. Sural nerve injury can be minimized using CAMIR by carefully placing the suture channel with a stab incision and special trocar based on a modified Bunnel suture technique.

[Clinical anatomy study on autonomic nerves related to anterior approach lumbar surgery ]

OBJECTIVE

To understand the location characteristics of the lumbosacral autonomic nerve plexus and the morphological changes so as to provide the anatomic theoretical basis for the protection of autonomic nerve during the lower lumbar anterior approach operation.

METHODS

A random anatomic investigation was carried out on 19 formalin-treated adult cadavers (15 males and 4 females; aged 44-78 years, mean 64 years). The anterior median line (connection of suprasternal fossa point and the midpoint of the symphysis pubis) was determined, and the characteristics of abdominal aortic plexus (AAP), inferior mesenteric plexus (IMP), and superior hypogastric plexus (SHP) were observed. The relationship between the autonomic nerve and the anterior median line was measured and recorded.

RESULTS

APP and IMP were found to be located chiefly in front of the abdominal aorta in a reticular pattern, and the nerve fibers of the two nerve plexuses were more densely at the left side of abdominal aorta than at the right side. Superior hypogastric plexus showed more distinct main vessel variations, including 4 types. The main vessel length of the SHP was (59.38 ± 12.86) mm, and the width was (11.25 ± 2.92) mm. The main vessels of SHP were mainly located at the left side of the ventral median line (10, 52.6%) and anterior lumbar vertebra (13, 68.4%). The main vessels extended down to form the left and right hypogastric nerves.

CONCLUSION

It is applicable to expose the nerve from the right side of centrum and move the autonomic nerve and blood vessel as a whole during anterior lower lumbar operation. In this way, the dissection to separate nerve plexus is not needed, thus nerve injury can be avoided to the largest extent.

Bad medicine: prescription drugs, preemption, and the potential for a no-fault fix

For decades, federal regulation of pharmaceutical drugs and medical devices has worked hand in hand with state tort claims to protect the health and safety of the American public. Now, a new trend toward preemption endangers this scheme. In recent years, the Supreme Court has given increasing deference to agency assertions about their preemptive authority and has found preemption in an increasing number of cases. In the process, the Supreme Court has preempted claims for medical device injuries and left claims for pharmaceutical harms in a precarious position. The elimination of common law claims for drug and device harms will leave holes in the FDA's regulatory scheme, endangering the health and safety of Americans. It will also prevent ordinary Americans from seeking compensation for their injuries--even those injuries caused by manufacturer malfeasance. This Article proposes that Congress create a no-fault compensation scheme for drugs and medical devices to close these gaps. Such a scheme could be both practical and politically possible, satisfying manufacturers, tort reformers, patients, and plaintiffs' lawyers alike.

The additive erectile recovery effect of brain-derived neurotrophic factor combined with vascular endothelial growth factor in a rat model of neurogenic impotence

OBJECTIVE

To test the hypothesis that combined intracavernosal injection with vascular endothelial growth factor (VEGF) with adeno-associated virus-mediated brain-derived neurotrophic factor (AAV-BDNF) synergistically facilitates the neural regeneration and erectile function after cavernosal nerve injury.

MATERIALS AND METHODS

Forty Sprague-Dawley male rats were randomly divided into five equal groups: eight had a sham operation while 32 had bilateral cavernosal nerve freezing followed by an immediate intracavernosal injection with either phosphate-buffered saline (PBS), VEGF, AAV-BDNF, or AAV-BDNF + VEGF. Erectile function was assessed by cavernosal nerve electrostimulation at 3 months, and samples of the major pelvic ganglia and penile tissue were evaluated histologically.

RESULTS

In this animal model of impotence from nerve injury, the recovery of erectile function was greatest in those receiving AAV-BDNF + VEGF; the mean (sd) maximal intracavernosal pressure in this group was 87.2 (20.78) cmH2O, compared with 37.3 (11.39) for VEGF alone and 49.8 (29.58) for AAV-BDNF alone. No erectile dysfunction was identified in the sham group, with a pressure of 100.7 (22.70) cmH2O, while all treatment groups significantly outperformed the PBS (control) group, at 29.3 (13.52) cmH2O. Furthermore, all animals receiving monotherapy or combined treatment had more NADPH-diaphorase-positive nerve fibres than controls but less than in the sham group.

CONCLUSION

Bilateral cavernosal nerve freezing causes erectile dysfunction with accompanying neurological changes. Intracavernosal injection with either VEGF or AAV-BDNF alone enhances nerve regeneration, with combined therapy (VEGF and AAV-BDNF) promoting neural and erectile recovery additively.

Expected outcomes after pelvic ring injury

Pelvic ring injuries are a result of high-energy trauma and are often associated with nonskeletal injuries. Although malunions and nonunions are rare with the use of current techniques of reduction and fixation, outcome studies show that these injuries have long-lasting effects. Associated urologic and neurologic injuries are commonly the determinants of outcome.

[Effect of tramadol on regeneration after experimental sciatic nerve injury]

Abnormal impulses in peripheral nerves play a critical role in neuropathic pain syndromes. The voltage-gated Na+ channels that underlie the action potential are main targets for clinically useful drugs in the pain therapy. Systemic tramadol has been shown to have clinical efficacy against some forms of neuropathic pain. Therefore, we investigated the mechanisms of action of tramadol by an in vitro model by sucrose-gap technique. Tramadol produced concentration-dependent and frequency-dependent decrements in CAP amplitude. Also, injured nerves were more sensitive to tramadol. Tramadol decreased the amplitude of the delayed depolarization and the hyperpolarizing afterpotentials. In conclusion, blocking potencies of small concentration tramadol on the delayed depolarization and hyperpolarizing afterpotential in regeneration period may be contributed for understanding of the action mechanisms of tramadol on neuropathic pain therapy.

Fas-beyond death: a regenerative role for Fas in the nervous system

Fas (CD95, APO-1), a member of the TNF superfamily, is a prototypical "death receptor" which transduces apoptotic signals in a variety of cell types. However, cell death is not the only possible outcome of Fas signalling. Fas engagement by Fas Ligand can also trigger proliferation or differentiation, promote tumour progression and angiogenesis, and induce cytokine secretion and integrin expression. Recently, we have reported that Fas engagement induces a potent regenerative response in sensory neurons in vitro, and enhances peripheral nerve regeneration in vivo. In contrast, other types of neurons, notably motoneurons, are acutely sensitive to Fas-induced apoptosis. Here, we review the literature on non-apoptotic Fas signalling pathways, and discuss the potential roles, molecular mechanisms, and regulators of Fas signalling in the nervous system.

[The neurologic diseases]

Neurologic diseases have important social and economic repercussions. The economic cost related to medications, caretakers, and therapists is evident, as well as the impact the disease may cause on the family. Epilepsy is the most frequent cause of medical care at the out-patient service of the Manuel Velasco Suárez National Institute of Neurology and Neurosurgery (NINN), in Mexico City and the estimated annual prevalence of this disease is 5.9 per 1,000 inhabitants. Parkinson's disease, the most representative of movement disorders, affects 20% of the populating aged > 65 years. Depression and dementia are complex and heterogeneous neuropsychiatry disorders, representing the fifth cause of morbility after accidents, cardiovascular disease, liver cirrhosis and diabetes mellitus. During the last decades, encephalic trauma has been the first cause of mortality: among brain tumors, glioblastomas have the greatest impact. Among infectious disease of the central nervous system (CNS), which are relatively infrequent as compared to gastrointestinal or respiratory infections; viral encephalitis, AIDS-associated toxoplasmosis, and tuberculous meningitis are the most frequent discharge diagnoses at the NINN. The need for a national registration system of neurologic diseases is unquestionable. Such a system would provide accurate data regarding the magnitude of problems related with such disease and help design adequate care and prevention programs.

Multiple actions of pituitary adenylyl cyclase activating peptide in nervous system development and regeneration

Pituitary adenylyl cyclase activating peptide (PACAP) is widely expressed in the embryonic brain at the onset of neurogenesis, and is strongly upregulated in several models of nerve injury. Moreover, high-affinity PACAP receptors are expressed in proliferative zones in the embryonic and postnatal nervous system suggesting that PACAP regulates the development of both neuronal and glial precursors. Tissue culture studies indicate that PACAP exerts a variety of growth factor-like actions that depend on the origin of the cell population and developmental stage. These effects include regulation of proliferation, survival, maturation, neurite outgrowth, and expression of trophic factors, cytokines and trk receptors. The presence of other growth factors can also markedly affect these actions of PACAP, for example, reversing PACAP's effect from proliferative to antiproliferative. In vivo models now provide additional evidence that PACAP acts in neural development and regeneration.

Overcoming the challenges of neuropathic pain

Neuropathic pain can originate from a variety of conditions. Early treatment is vital. Nurses have an important role in initiating treatment and providing ongoing pain management and support for patients.

Wallerian degeneration of injured axons and synapses is delayed by a Ube4b/Nmnat chimeric gene

Axons and their synapses distal to an injury undergo rapid Wallerian degeneration, but axons in the C57BL/WldS mouse are protected. The degenerative and protective mechanisms are unknown. We identified the protective gene, which encodes an N-terminal fragment of ubiquitination factor E4B (Ube4b) fused to nicotinamide mononucleotide adenylyltransferase (Nmnat), and showed that it confers a dose-dependent block of Wallerian degeneration. Transected distal axons survived for two weeks, and neuromuscular junctions were also protected. Surprisingly, the Wld protein was located predominantly in the nucleus, indicating an indirect protective mechanism. Nmnat enzyme activity, but not NAD+ content, was increased fourfold in WldS tissues. Thus, axon protection is likely to be mediated by altered ubiquitination or pyridine nucleotide metabolism.

[Analysis of 700 orthopedic complaints reported to the Norwegian Patient Compensation System]

BACKGROUND

In the 1993-99 period, the NPCS reached decisions on 4,041 orthopaedic injury cases. This paper reviews the complaints lodged.

MATERIAL AND METHODS

We have analysed data from 700 randomly selected cases in order to elucidate the reasons for complaint.

RESULTS

Complaints were lodged against all types of hospitals and primary health care providers. The most frequent primary diagnosis were osteoarthritis of the hip, lumbar disc herniation, and various fractures. Complaints were most commonly related to faulty treatment, continued pain, nerve injuries, reduced function, mistaken diagnosis, malposition of bone or joint, and infection. 84% of complaints were related to treatment and to operative treatment in particular. In 209 cases (30%), the complaints were heard. Of these 209, 43% were heard because of the treatment given, 21% because of infection, 18% because of diagnostic fault, and 6% because of defective follow-up. 491 complaints were rejected; in 70% of them because the injury was acceptable according to general rules, in 19% because the basic disorder had caused the injury, and in 7% because there was in fact no injury.

INTERPRETATION

In our opinion, better knowledge about treatment injury cases represents valuable information that contributes to a higher quality of care.

Intraoperative, perioperative, and long-term complications of radical prostatectomy

With improved surgical technique and perioperative care, the intraoperative and early postoperative complications of radical prostatectomy have decreased over the last 2 decades. Incontinence and impotence are two of the most significant long-term complications related to this procedure. Although the wide range of incontinence and impotence rates reported has been attributed to multiple factors, including the method of data collection and patient selection, it is apparent that the surgeon's experience is a significant factor, and that lower long-term morbidity can be expected from centers with more experience with radical prostatectomies. The impact of long-term complications, including urinary and sexual dysfunction, on the quality of life may be less than previously reported and should be discussed with patients.