Injured Nerve Research Articles

Accuracy of MR neurography as a diagnostic tool in detecting injuries to the lingual and inferior alveolar nerve in patients with iatrogenic post-traumatic trigeminal neuropathy

ObjectivesMR neurography has the ability to detect and depict peripheral nerve injuries. This study evaluated the potential of MR neurography in the diagnosis of post-traumatic trigeminal neuropathy.MethodsForty-one participants prospectively underwent MR neurography of the lingual and inferior alveolar nerves using a 3D TSE STIR black-blood sequence. Two blinded and independent observers recorded the following information for each nerve of interest: presence of injury, nerve thickness, nerve signal intensity, MR neurography Sunderland class, and signal gap. Afterwards, the apparent nerve-muscle contrast-to-noise ratio and apparent signal-to-noise ratio were calculated. Clinical data (neurosensory testing score and clinical Sunderland class) was extracted retrospectively from the medical records of patients diagnosed with post-traumatic trigeminal neuropathy.ResultsCompared to neurosensory testing, MR neurography had a sensitivity of 38.2% and specificity of 93.5% detecting nerve injuries. When differentiated according to clinical Sunderland class, sensitivity was 19.1% in the presence of a low class injury (I to III) and improved to 83.3% in the presence of a high class (IV to V). Specificity remained unchanged. The area under the curve using the apparent nerve-muscle contrast-to-noise ratio, apparent signal-to-noise ratio, and nerve thickness to predict the presence of an injury was 0.78 (p < .05). Signal intensities and nerve diameter increased in injured nerves (p < .05). Clinical and MR neurography Sunderland scores positively correlated (correlation coefficient = 0.53; p = .005).ConclusionsThis study shows that MR neurography can accurately differentiate between injured and healthy nerves, especially in the presence of a more severe nerve injury.Clinical relevance statementMR neurography is not only able to detect trigeminal nerve injuries, but it can also provide information about the anatomical specifications of the injury, which is not possible with clinical neurosensory testing. This makes MR neurography an added value in the management of post-traumatic trigeminal neuropathy.Key Points• The current diagnosis of post-traumatic trigeminal neuropathy is mainly based on clinical examination.• MR neurography is able to visualize and stratify peripheral trigeminal nerve injuries.• MR neurography contributes to the diagnostic process as well as to further decision-making.

Electroconductive and Immunomodulatory Natural Polymer‐Based Hydrogel Bandages Designed for Peripheral Nerve Regeneration

AbstractSuccessful regeneration of the peripheral nerve relies on the collaborative efforts of neural cells and immune cells. Conductive hydrogels have yielded promising results in supporting axonal growth; however, their inability to regulate the immune response and their poor biological integration with tissues hinder the repair of injured peripheral nerves. Herein, an adhesive conductive immunomodulatory nerve hydrogel bandage is developed for nerve regeneration. The nerve bandage hydrogel is prepared from the bioactive material extracellular matrix (ECM), oxidized polysaccharides, and poly(3,4‐ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT:PSS) by self‐assembly and dynamic Schiff base cross‐linking. The drug indole‐3‐propionic acid (IPA) is loaded into nerve bandages and contributes to the rapid chemotaxis of neutrophils in the dorsal root ganglia and modulation of the immune system. In addition, the conductive hydrogel bandage exhibits close conformal contact with the injured nerve, forming a stable and tightly coupled electrical bridge with the electroresponsive neural tissue. In summary, the nerve bandage effectively promote nerve regeneration and enable both anatomical and functional recovery of neural tissue while preventing muscle atrophy. This work provides a new strategy for peripheral nerve regeneration and may have critical clinical applications in the future.

Evaluation of trans- and cis-4-[18F]Fluorogabapentin for Brain PET Imaging.

Gabapentin, a selective ligand for the α2δ subunit of voltage-dependent calcium channels, is an anticonvulsant medication used in the treatment of neuropathic pain, epilepsy, and other neurological conditions. We recently described two radiofluorinated derivatives of gabapentin (trans-4-[18F]fluorogabapentin, [18F]tGBP4F, and cis-4-[18F]fluorogabapentin, [18F]cGBP4F) and showed that these compounds accumulate in the injured nerves in a rodent model of neuropathic pain. Given the use of gabapentin in brain diseases, here we investigate whether these radiofluorinated derivatives of gabapentin can be used for imaging α2δ receptors in the brain. Specifically, we developed automated radiosynthesis methods for [18F]tGBP4F and [18F]cGBP4F and conducted dynamic PET imaging in adult rhesus macaques with and without preadministration of pharmacological doses of gabapentin. Both radiotracers showed very high metabolic stability, negligible plasma protein binding, and slow accumulation in the brain. [18F]tGBP4F, the isomer with higher binding affinity, showed low brain uptake and could not be displaced, whereas [18F]cGBP4F showed moderate brain uptake and could be partially displaced. Kinetic modeling of brain regional time-activity curves using a metabolite-corrected arterial input function shows that a one-tissue compartment model accurately fits the data. Graphical analysis using Logan or multilinear analysis 1 produced similar results as compartmental modeling, indicating robust quantification. This study advances our understanding of how gabapentinoids work and provides an important advancement toward imaging α2δ receptors in the brain.

M2 macrophage-derived cathepsin S promotes peripheral nerve regeneration via fibroblast–Schwann cell-signaling relay

BackgroundAlthough peripheral nerves have an intrinsic self-repair capacity following damage, functional recovery is limited in patients. It is a well-established fact that macrophages accumulate at the site of injury. Numerous studies indicate that the phenotypic shift from M1 macrophage to M2 macrophage plays a crucial role in the process of axon regeneration. This polarity change is observed exclusively in peripheral macrophages but not in microglia and CNS macrophages. However, the molecular basis of axonal regeneration by M2 macrophage is not yet fully understood. Herein, we aimed to identify the M2 macrophage-derived axon regeneration factor.MethodsWe established a peripheral nerve injury model by transection of the inferior alveolar nerve (IANX) in Sprague–Dawley rats. Transcriptome analysis was performed on the injured nerve. Recovery from sensory deficits in the mandibular region and histological reconnection of IAN after IANX were assessed in rats with macrophage depletion by clodronate. We investigated the effects of adoptive transfer of M2 macrophages or M2-derived cathepsin S (CTSS) on the sensory deficit. CTSS initiating signaling was explored by western blot analysis in IANX rats and immunohistochemistry in co-culture of primary fibroblasts and Schwann cells (SCs).ResultsTranscriptome analysis revealed that CTSS, a macrophage-selective lysosomal protease, was upregulated in the IAN after its injury. Spontaneous but partial recovery from a sensory deficit in the mandibular region after IANX was abrogated by macrophage ablation at the injured site. In addition, a robust induction of c-Jun, a marker of the repair-supportive phenotype of SCs, after IANX was abolished by macrophage ablation. As in transcriptome analysis, CTSS was upregulated at the injured IAN than in the intact IAN. Endogenous recovery from hypoesthesia was facilitated by supplementation of CTSS but delayed by pharmacological inhibition or genetic silencing of CTSS at the injured site. Adoptive transfer of M2-polarized macrophages at this site facilitated sensory recovery dependent on CTSS in macrophages. Post-IANX, CTSS caused the cleavage of Ephrin-B2 in fibroblasts, which, in turn, bound EphB2 in SCs. CTSS-induced Ephrin-B2 cleavage was also observed in human sensory nerves. Inhibition of CTSS-induced Ephrin-B2 signaling suppressed c-Jun induction in SCs and sensory recovery.ConclusionsThese results suggest that M2 macrophage-derived CTSS contributes to axon regeneration by activating SCs via Ephrin-B2 shedding from fibroblasts.

FOSL1 modulates Schwann cell responses in the wound microenvironment and regulates peripheral nerve regeneration

Peripheral glial Schwann cells switch to a repair state after nerve injury, proliferate to supply lost cell population, migrate to form regeneration tracks, and contribute to the generation of a permissive microenvironment for nerve regeneration. Exploring essential regulators of the repair responses of Schwann cells may benefit the clinical treatment for peripheral nerve injury. In the present study, we find that FOSL1, a AP-1 member that encodes transcription factor FOS Like 1, is highly expressed at the injured sites following peripheral nerve crush. Interfering FOSL1 decreases the proliferation rate and migration ability of Schwann cells, leading to impaired nerve regeneration. Mechanism investigations demonstrate that FOSL1 regulates Schwann cell proliferation and migration by directly binding to the promoter of EPH Receptor B2 (EPHB2) and promoting EPHB2 transcription. Collectively, our findings reveal the essential roles of FOSL1 in regulating the activation of Schwann cells and indicate that FOSL1 can be targeted as a novel therapeutic approach to orchestrate the regeneration and functional recovery of injured peripheral nerves.

Anatomic Anomalies of the Nerves Treated during Headache Surgery.

Headache surgery is a well-established, viable option for patients with chronic head pain/migraines refractory to conventional treatment modalities. These operations involve any number of seven primary nerves. In the occipital region, the surgical targets are the greater, lesser, and third occipital nerves. In the temporal region, they are the auriculotemporal and zygomaticotemporal nerves. In the forehead, the supraorbital and supratrochlear are targeted. The typical anatomic courses of these nerves are well established and documented in clinical and cadaveric studies. However, variations of this "typical" anatomy are quite common and relatively poorly understood. Headache surgeons should be aware of these common anomalies, as they may alter treatment in several meaningful ways. In this article, we describe the experience of five established headache surgeons encompassing over 4000 cases with respect to the most common anomalies of the nerves typically addressed during headache surgery. Descriptions of anomalous nerve courses and suggestions for management are offered. Anomalies of all seven nerves addressed during headache operations occur with a frequency ranging from 2% to 50%, depending on anomaly type and nerve location. Variations of the temporal and occipital nerves are most common, whereas anomalies of the frontal nerves are relatively less common. Management includes broader dissection and/or transection of accessory injured nerves combined with strategies to reduce neuroma formation such as targeted reinnervation or regenerative peripheral nerve interfaces. Understanding these myriad nerve anomalies is essential to any headache surgeon. Implications are relevant to preoperative planning, intraoperative dissection, and postoperative management.

Development of a Semifascicle Graft Technique to Bridge Peripheral Nerve Defect: A Case Report and Animal Study.

Autologous nerve grafting, the criterion standard for bridging peripheral nerves, can cause complications at the donor site. We investigated a novel approach to reconstruct the nerve gap with a split cross-sectional unmatched semifascicle autograft, which was harvested from the distal part of the injured nerve. A patient diagnosed with left-sided frontal branch facial nerve dissection underwent nerve bridging emergency surgery using a semifascicle nerve graft. A sciatic nerve model was used to validate the feasibility and mechanism of this method. Male Sprague-Dawley rats (n = 36) were randomized into (A) intact fascicle, (B) semifascicle, and (C) semifascicle + conduit groups and further subdivided into 4- and 8-week groups for histological analysis of the neurotissue area, fibers, and Schwann cells. The 8-week groups underwent weekly pain and temperature tests; the wet weight of the gastrocnemius muscle was measured after euthanasia. The frontalis of the patient's injured side exhibited movement at 2 months postsurgery and recovered a symmetrical appearance at 13 months. Group A exhibited more neurotissue areas and fibers than groups B and C at week 4; group B had more neurotissue than group C. Group A had greater neurotissue areas than groups B and C at week 8; groups B and C exhibited no differences. The groups displayed no differences regarding nerve fiber, pain, and temperature analysis at week 8. Muscle wet weight of groups A and B exhibited no differences and was higher than that of group C. We demonstrated the clinical translational value of semifascicle nerve grafts; the injured site was both the donor and recipient, thereby avoiding donor site damage and associated complications.

Pengaruh Manual Mobilisasi Saraf Terhadap Penurunan Nyeri Pada Pasien Ischialgia Pasca Terapi IR Dan TENS Di RSD KRMT Wongsonegoro Semarang

Low back pain (NPB) Ischialgia is the pinching of the ischiadic nerve in the lower back region which causes the buttocks, thighs, lower legs and even feet to tingle, pain, sometimes causing weakness. Nerve mobilization is a manipulation technique by moving and stretching the nerve tissue to improve axonal transport so as to improve nerve conduction. Nerve mobilization can reduce the pressure in the nerve so that there is an increase in blood flow to the nerve, which can have a regenerating and healing effect on the injured nerve (Butler, 1991). Nerve mobilization is often used as a form of diagnosis and treatment in musculoskeletal conditions with nerve involvement (Butler, 1991). Nerve mobilization in the Lower Limb Tension Test (LLTT) is performed on the branching of the lumbosacral plexus such as the ishiadicus nerve, peroneal nerve, and tibial nerve. But here the author only discusses LLTT on the ishiadicus nerve, namely LLTT 1 which is associated with low back pain. The purpose of knowing the effect of manual nerve mobilization on pain reduction in Ischialgia patients after IR and TENS therapy at RSD KRMT Wongsonegoro Semarang. Method two group pre test and post test. The place of this research is in the physiotherapy clinic of KRMT Wongsonegoro Hospital. Using Visual Analouge Scale (VAS) measuring instrument. The results were treated using the mann-Whtney test. With confidence interval (CI) (95%) The results revealed that there was a significant difference in pain between group 1 (p = 0.00) and group 2 (p = 0.00). But there was no significant difference between the two groups on pain improvement (p = 0.152), so there was no better treatment between the two groups. It is concluded that ULTT is useful in the treatment of LBP patients to reduce pain in two groups. The targeted output is publication in Sinta indexed national journals and IPR. The TKT target of the implementation of gamelan accompaniment gymnastics is at level 2.

Trigeminal or peripheral nerve stimulation improves functional outcomes of nerve recovery in a rodent forelimb gap repair model

The hypothesis of this study was that trigeminal nerve stimulation (TNS) or peripheral nerve stimulation (PNS) could improve functional outcomes of peripheral nerve injury in a rat forelimb model when compared to control rats not receiving electrical stimulation (ES). While PNS is known to improve outcomes after nerve surgery, the role of TNS has not been explored. Lewis rats were trained to perform a reach and grasp task before receiving a 2mm gap repair of the ulnar and median nerves and randomized into four treatment groups: (1) sham injury, (2) nerve injury with sham ES, (3) nerve injury with PNS, and (4) nerve injury with TNS. Functional motor (median pull force and percent success in motor task) and sensory metrics (forelimb paw withdrawal thresholds) were collected both pre-injury and throughout rehabilitation. Nerves stained using Gomori's trichrome were assessed quantitatively and qualitatively. The sham ES group did not recover their pre-injury baseline functional outcomes. In contrast, the TNS and PNS groups fully recovered following injury, with no difference in functional outcomes between the pre-injury baseline and the final week of rehabilitation (P>0.05, all). Histomorphology results demonstrated no quantitative difference, but qualitative differences in architecture were evident. Electrical stimulation of the trigeminal nerve or the injured nerve improved the functional outcomes of nerve regeneration in rodents. Histomorphology results of nerves from the TNS group support the proposed central mechanisms. This is an important step in translating this therapy as an adjunct, non-invasive treatment for high, mixed nerve injuries in humans.

Improving outcomes in traumatic peripheral nerve injuries to the upper extremity.

Peripheral nerve lesions of the upper extremity are common and are associated with devastating limitations for the patient. Rapid and accurate diagnosis of the lesion by electroneurography, neurosonography, or even MR neurography is important for treatment planning. There are different therapeutic approaches, which may show individual differences depending on the injured nerve. If a primary nerve repair is not possible, several strategies exist to bridge the gap. These may include autologous nerve grafts, bioartificial nerve conduits, or acellular nerve allografts. Tendon and nerve transfers are also of major importance in the treatment of nerve lesions in particular with long regeneration distances. As a secondary reconstruction, in addition to tendon transfers, there is also the option for free functional muscle transfer. In amputations, the prevention of neuroma is of great importance, for which different strategies exist, such as target muscle reinnervation, regenerative peripheral nerve interface, or neurotized flaps. In this article, we give an overview of the latest methods for the therapy of peripheral nerve lesions.

Ultrasound-Targeted Microbubble Destruction Assisted Delivery of Platelet-Rich Plasma-Derived Exosomes Promoting Peripheral Nerve Regeneration.

Peripheral nerve injury is prevalent and has a high disability rate in clinical settings. Current therapeutic methods have not achieved satisfactory efficacy, underscoring the need for novel approaches to nerve restoration that remains an active area of research in neuroscience and regenerative medicine. In this study, we isolated platelet-rich plasma-derived exosomes (PRP-exos) and found that they can significantly enhance the proliferation, migration, and secretion of trophic factors by Schwann cells (SCs). In addition, there were marked changes in transcriptional and expression profiles of SCs, particularly via the upregulation of genes related to biological functions involved in nerve regeneration and repair. In the rat model of sciatic nerve crush injury, ultrasound-targeted microbubble destruction (UTMD) enhanced the efficiency of PRP-exos delivery to the injury site. This approach ensured a high concentration of PRP-exos in the injured nerve and improved the therapeutic outcomes. In conclusion, PRP-exos may promote nerve regeneration and repair, and UTMD may increase the effectiveness of targeted PRP-exos delivery to the injured nerve and enhance the therapeutic effect.

Inflammatory Mediators of Axon Regeneration in the Central and Peripheral Nervous Systems.

Although most pathways in the mature central nervous system cannot regenerate when injured, research beginning in the late 20th century has led to discoveries that may help reverse this situation. Here, we highlight research in recent years from our laboratory identifying oncomodulin (Ocm), stromal cell-derived factor (SDF)-1, and chemokine CCL5 as growth factors expressed by cells of the innate immune system that promote axon regeneration in the injured optic nerve and elsewhere in the central and peripheral nervous systems. We also review the role of ArmC10, a newly discovered Ocm receptor, in mediating many of these effects, and the synergy between inflammation-derived growth factors and complementary strategies to promote regeneration, including deleting genes encoding cell-intrinsic suppressors of axon growth, manipulating transcription factors that suppress or promote the expression of growth-related genes, and manipulating cell-extrinsic suppressors of axon growth. In some cases, combinatorial strategies have led to unprecedented levels of nerve regeneration. The identification of some similar mechanisms in human neurons offers hope that key discoveries made in animal models may eventually lead to treatments to improve outcomes after neurological damage in patients.

Diagnostics and surgical treatment of painful neuromas

Painful neuromas that often develop after peripheral nerve injury require adequate diagnosis and treatment because of the suffering they cause. The scientific basis for the development of painful neuromas has not yet been sufficiently investigated. In addition to conservative procedures, alarger number of surgical techniques are available for treatment of painful neuromas. Areview of the basic principles, diagnostic and treatment options for painful neuromas. Presentation of the scientific basis regarding the development of painful neuromas. Illustration and discussion of the most common diagnostic and treatment procedures. The scientific basis regarding the development of painful neuromas after peripheral nerve injury has not yet been adequately developed. In order to be able to make acorrect diagnosis, the use of standardized diagnostic criteria and adequate imaging techniques are recommended. In the sense of aparadigm shift, the use of the formerly neuroma-bearing nerve for reinnervation of target organs is to be preferred over mere burying in adjacent tissue. In addition to standardized diagnostics the management of painful neuromas often requires a surgical intervention after all conservative therapeutic measures have been exhausted. As an alternative to restoring the continuity of the injured nerve, targeted reinnervation of electively denervated target organs by the formerly neuroma-bearing nerve is preferable over other techniques.

Inhibition of microtubule detyrosination by parthenolide facilitates functional CNS axon regeneration

Injured axons in the central nervous system (CNS) usually fail to regenerate, causing permanent disabilities. However, the knockdown of Pten knockout or treatment of neurons with hyper-IL-6 (hIL-6) transforms neurons into a regenerative state, allowing them to regenerate axons in the injured optic nerve and spinal cord. Transneuronal delivery of hIL-6 to the injured brain stem neurons enables functional recovery after severe spinal cord injury. Here we demonstrate that the beneficial hIL-6 and Pten knockout effects on axon growth are limited by the induction of tubulin detyrosination in axonal growth cones. Hence, cotreatment with parthenolide, a compound blocking microtubule detyrosination, synergistically accelerates neurite growth of cultured murine CNS neurons and primary RGCs isolated from adult human eyes. Systemic application of the prodrug dimethylamino-parthenolide (DMAPT) facilitates axon regeneration in the injured optic nerve and spinal cord. Moreover, combinatorial treatment further improves hIL-6-induced axon regeneration and locomotor recovery after severe SCI. Thus, DMAPT facilitates functional CNS regeneration and reduces the limiting effects of pro-regenerative treatments, making it a promising drug candidate for treating CNS injuries.

Inhibition of microtubule detyrosination by parthenolide facilitates functional CNS axon regeneration.

Injured axons in the central nervous system (CNS) usually fail to regenerate, causing permanent disabilities. However, the knockdown of Pten knockout or treatment of neurons with hyper-IL-6 (hIL-6) transforms neurons into a regenerative state, allowing them to regenerate axons in the injured optic nerve and spinal cord. Transneuronal delivery of hIL-6 to the injured brain stem neurons enables functional recovery after severe spinal cord injury. Here we demonstrate that the beneficial hIL-6 and Pten knockout effects on axon growth are limited by the induction of tubulin detyrosination in axonal growth cones. Hence, cotreatment with parthenolide, a compound blocking microtubule detyrosination, synergistically accelerates neurite growth of cultured murine CNS neurons and primary RGCs isolated from adult human eyes. Systemic application of the prodrug dimethylamino-parthenolide (DMAPT) facilitates axon regeneration in the injured optic nerve and spinal cord. Moreover, combinatorial treatment further improves hIL-6-induced axon regeneration and locomotor recovery after severe SCI. Thus, DMAPT facilitates functional CNS regeneration and reduces the limiting effects of pro-regenerative treatments, making it a promising drug candidate for treating CNS injuries.

The Effect of Adipose-Derived Mesenchymal Stem Cells on Peripheral Nerve Damage in a Rodent Model.

Peripheral nerve damage is a significant clinical problem with limited therapeutic options. Adipose-derived mesenchymal stem cells (ADSCs) have emerged as a promising therapeutic approach due to their regenerative potential. However, the underlying mechanisms by which ADSCs promote peripheral nerve regeneration remain unclear. In this study, we investigated the role of syndecan-1 and heat shock protein 70 (HSP-70) in mediating the regenerative effects of ADSCs on peripheral nerves. ADSCs were characterized and isolated from the adipose tissue of rats. In vitro experiments were conducted to evaluate the ability of ADSCs to secrete syndecan-1 and HSP-70 in response to stress conditions. To evaluate the therapeutic potential of ADSCs, rats with sciatic nerve injuries were treated with ADSCs and assessed for functional recovery, nerve regeneration, and changes in syndecan-1 and HSP-70 levels. Regeneration was evaluated with Electromyography (EMG) histology. The results showed that ADSCs could secrete syndecan-1 and HSP-70 in response to stress conditions. Furthermore, ADSC treatment significantly improved functional recovery and nerve regeneration and increased syndecan-1 and HSP-70 levels in the injured nerve. On the other hand, ADSCs make improvements histologically through the influence of Nerve growth factor (NGF), Malondialdehyde (MDA), and EMG.

Исследование роли нейротрофических факторов в регуляции регенерационных процессов в поврежденных соматических нервах при действии пептидного препарата «Семакс»

The content of neurotrophic factors in damaged somatic nerves under the action of the drug «Semax» was studied and their role in the regulation of regenerative processes in injured nerve conductors was established. It has been shown that intramuscular administration of the drug is accompanied by a significant increase in the level of NGF and NT-3 both in the proximal and distal parts of the nerve. At the same time, there are no significant changes in the quantitative content of neuroregulin-1 against the background of its use. The data obtained suggest that one of the mechanisms of action of Semax is its ability to interact with Schwann cells and stimulate the release of NGF and NT-3, which facilitate the regeneration of damaged axons and do not affect the synthesis of neuroregulin-1. In addition, the study of the quantitative content of individual protein fractions showed that the drug «Semax» has the most pronounced effect on the level of neurofilament-H in both segments of the nerve conductor, which indicates the important role and activation of the mitogen-activated protein kinase (MAPK / ERK) signalling pathway, which regulates processes of cytoskeletal protein synthesis and axon growth. Nevertheless, it was shown that in the variant of the experiment using Semax, there was a decrease in the level of GAP-43, which is a key marker of axonal growth, both in the proximal and distal segments of the nerve. The data obtained most likely indicate that the intramuscular administration of the drug does not affect the processes of axon growth, but is aimed at maintaining the survival of neurons and accelerated restoration of the functional state of nerve fibres, which is also confirmed by the appearance of an action potential and the ability of the nerve to conduct it against the background of the use of the Semax drug.

Secondary surgical procedures following motor nerve injuries

The functional deficits that develop after aperipheral nerve injury mean aconsiderable reduction in the quality of life for the affected patients. However, interventions on the injured nerve are not always possible or effective. In this case, secondary procedures, e.g. tendon transfers, are afeasible option for functional reconstruction. An overview of the most common secondary surgical procedures for functional reconstruction after peripheral nerve injuries. Presentation and discussion of the most common secondary surgical procedures with emphasis on tendon transfers. Illustration of the primary functions that need to be reconstructed depending on the respective nerve lesion. The basic principle of secondary surgical procedures after nerve injuries is the transposition of ahealthy tendomuscular unit to replace alost function following aloss of muscle or tendon or if an intervention on the nerve is not promising. For example, by transferring flexor forearm muscles, wrist, finger and thumb extension can be reconstructed after radial nerve injury. By transposing the tibialis posterior muscle, dorsiflexion in the talocrural joint can be restored to enable the affected patient to walk safely without an orthosis. Secondary surgical procedures are avaluable option for functional reconstruction after nerve injury.

Cervical intradural traumatic neuroma without history of trauma: illustrative case.

Traumatic neuroma typically refers to a reactive process in the injured peripheral nerve, characterized by an excessive growth of axons, Schwann cells, and fibroblasts at the proximal end of the nerve after its interruption. The authors report a case of a traumatic neuroma in the cervical nerve root in a patient with no history of trauma. The patient presented with sensation loss in the right-hand ulnar distribution, right flank around the T4-11 region, and right small toe along with motor power weakness over the right upper and lower extremity. Magnetic resonance imaging revealed an intradural extramedullary mass lesion with extension along the C7 nerve root. Histological examination showed traumatic neuroma. A total resection of the lesion along with the resolution of sensory and motor deficits was achieved directly after surgery. Traumatic neuroma should always be kept in the armamentarium for diagnosis of an intradural nerve sheath tumor.

Robust and Multifunctional Nanoparticles Assembled from Natural Polyphenols and Metformin for Efficient Spinal Cord Regeneration.

The treatment of spinal cord injury (SCI) remains unsatisfactory owing to the complex pathophysiological microenvironments at the injury site and the limited regenerative potential of the central nervous system. Metformin has been proven in clinical and animal experiments to repair damaged structures and functions by promoting endogenous neurogenesis. However, in the early stage of acute SCI, the adverse pathophysiological microenvironment of the injury sites, such as reactive oxygen species and inflammatory factor storm, can prevent the activation of endogenous neural stem cells (NSCs) and the differentiation of NSCs into neurons, decreasing the whole repair effect. To address those issues, a series of robust and multifunctional natural polyphenol-metformin nanoparticles (polyphenol-Met NPs) were fabricated with pH-responsiveness and excellent antioxidative capacities. The resulting NPs possessed several favorable advantages: First, the NPs were composed of active ingredients with different biological properties, without the need for carriers; second, the pH-responsiveness feature could allow targeted drug delivery at the injured site; more importantly, NPs enabled drugs with different performances to exhibit strong synergistic effects. The results demonstrated that the improved microenvironment by natural polyphenols boosted the differentiation of activated NSCs into neurons and oligodendrocytes, which could efficiently repair the injured nerve structures and enhance the functional recovery of the SCI rats. This work highlighted the design and fabrication of robust and multifunctional NPs for SCI treatment via efficient microenvironmental regulation and targeted NSCs activation.