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Handchirurgie, Mikrochirurgie,... Feb 2024Lesions of peripheral nerves of the upper extremities often lead to persistent, serious limitations in motor function and sensory perception. Affected patients suffer...
BACKGROUND
Lesions of peripheral nerves of the upper extremities often lead to persistent, serious limitations in motor function and sensory perception. Affected patients suffer from both private and professional restrictions associated with long-term physical, psychological and socioeconomic consequences.
INDICATION
An early indication for a nerve transfer shortens the reinnervation distance and improves the growing of motor and sensory axons into the target organ to facilitate early mobility and sensitivity. When planning the timepoint of the surgical procedure, the distance to be covered by reinnervation as well as the morbidities of donor nerves must be considered individually.
RESULTS
Nerve transfers can achieve earlier and safer reinnervation to improve motor and sensory functions after nerve injuries in the upper extremity.
Topics: Humans; Nerve Transfer; Peripheral Nerves; Upper Extremity; Sensation; Nerve Regeneration; Peripheral Nerve Injuries
PubMed: 38316412
DOI: 10.1055/a-2228-7062 -
International Journal of Molecular... Mar 2024With the development of single-cell sequencing technology, the cellular composition of more and more tissues is being elucidated. As the whole nervous system has been... (Review)
Review
With the development of single-cell sequencing technology, the cellular composition of more and more tissues is being elucidated. As the whole nervous system has been extensively studied, the cellular composition of the peripheral nerve has gradually been revealed. By summarizing the current sequencing data, we compile the heterogeneities of cells that have been reported in the peripheral nerves, mainly the sciatic nerve. The cellular variability of Schwann cells, fibroblasts, immune cells, and endothelial cells during development and disease has been discussed in this review. The discovery of the architecture of peripheral nerves after injury benefits the understanding of cellular complexity in the nervous system, as well as the construction of tissue engineering nerves for nerve repair and axon regeneration.
Topics: Humans; Axons; Endothelial Cells; Nerve Regeneration; Schwann Cells; Sciatic Nerve; Peripheral Nerve Injuries
PubMed: 38542483
DOI: 10.3390/ijms25063511 -
Current Pain and Headache Reports Oct 2023Though peripheral nerve stimulation has long been utilized in the field of chronic pain management, its use in acute pain management in the postoperative period is... (Review)
Review
PURPOSE OF REVIEW
Though peripheral nerve stimulation has long been utilized in the field of chronic pain management, its use in acute pain management in the postoperative period is relatively novel and warrants further consideration.
RECENT FINDINGS
In the postsurgical period, peripheral nerve stimulation may offer an additional low-risk, opioid-sparing analgesic option, which is particularly pertinent in the setting of the ongoing opioid epidemic, as inadequate postsurgical analgesia has been shown to increase the risk of developing persistent or chronic postsurgical pain. In this review, we discuss the current literature that illustrate the emerging role of peripheral nerve stimulation as an effective treatment modality in the postoperative period for the management of acute pain, as various studies have recently been conducted evaluating the feasibility of utilizing percutaneous peripheral nerve stimulation as an adjunct in postsurgical analgesia. Nonetheless, future studies are necessary to continue to elucidate the short- and long-term impacts of peripheral nerve stimulation use in acute postsurgical analgesia.
Topics: Humans; Transcutaneous Electric Nerve Stimulation; Analgesia; Pain Management; Pain, Postoperative; Analgesics, Opioid; Peripheral Nerves
PubMed: 37556045
DOI: 10.1007/s11916-023-01159-6 -
Bioengineering approaches for nerve graft revascularization: Current concepts and future directions.WIREs Mechanisms of Disease 2023Peripheral nerve injury (PNI) is the most common neurological injury in civilian and military injuries, with over 360,000 PNI procedures performed in the US yearly.... (Review)
Review
Peripheral nerve injury (PNI) is the most common neurological injury in civilian and military injuries, with over 360,000 PNI procedures performed in the US yearly. Segmental loss of nerve tissue results in a nerve gap precluding a tension-free primary repair, and in these cases, interpositional autologous or acellular nerve allografts are used to bridge the gap. Graft ischemia time is a critical factor in achieving satisfactory nerve regeneration. Rapid nerve graft revascularization is essential in order to sustain Schwann cell growth which in turn is crucial for axonal regeneration. Currently, nerve autografts are considered the gold standard for segmental nerve gaps but are associated with several disadvantages such as limited supply of expendable donor tissue, increased operative time, and donor site morbidity. Hence, readily available, off-the-shelf nerve allografts or scaffolds are being investigated since they provide advantages such as a virtually limitless sourcing, a wide variety of sizes to match recipient nerves, and no donor site morbidity. New, exciting advances in tissue engineering to augment revascularization of nerve allografts or conduits have been investigated. Strategies include pro-angiogenic mesenchymal stem cells, extracellular vesicles, functionalized scaffolds, bioactive peptides, and three-dimensional bioprinting. This article discusses these bioengineering advances and future strategies aimed at enhancing nerve graft and scaffold revascularization. This article is categorized under: Neurological Diseases > Biomedical Engineering Neurological Diseases > Molecular and Cellular Physiology.
Topics: Humans; Biomedical Engineering; Peripheral Nerve Injuries; Tissue Engineering; Schwann Cells; Transplantation, Homologous
PubMed: 37102333
DOI: 10.1002/wsbm.1609 -
Glia Jul 2023Our previous studies indicated that RhoA knockdown or inhibition could alleviate the proliferation, migration, and differentiation of Schwann cells. However, the role of...
Our previous studies indicated that RhoA knockdown or inhibition could alleviate the proliferation, migration, and differentiation of Schwann cells. However, the role of RhoA in Schwann cells during nerve injury and repair is still unknown. Herein, we developed two lines of Schwann cells conditional RhoA knockout (cKO) mice by breeding RhoA mice with Plp or Dhh mice. Our results indicate that RhoA cKO in Schwann cells accelerates axonal regrowth and remyelination after sciatic nerve injury, which enhances the recovery of nerve conduction and hindlimb gait, and alleviates the amyotrophy in gastrocnemius muscle. Mechanistic studies in both in vivo and in vitro models revealed that RhoA cKO could facilitate Schwann cell dedifferentiation via JNK pathway. Schwann cell dedifferentiation subsequently promotes Wallerian degeneration by enhancing phagocytosis and myelinophagy, as well as stimulating the production of neurotrophins (NT-3, NGF, BDNF, and GDNF). These findings shed light on the role of RhoA in Schwann cells during nerve injury and repair, indicating that cell type-specific RhoA targeting could serve as a promising molecular therapeutic strategy for peripheral nerve injury.
Topics: Mice; Animals; Cell Dedifferentiation; Sciatic Nerve; Schwann Cells; Sciatic Neuropathy; Nerve Regeneration; Peripheral Nerve Injuries
PubMed: 36971019
DOI: 10.1002/glia.24365 -
Acta Chirurgica Belgica Dec 2023The aim of this study was to assess the safety and efficacy of major amputation under ultrasound-guided peripheral nerve blocks in critical peripheral artery disease... (Review)
Review
OBJECTIVE
The aim of this study was to assess the safety and efficacy of major amputation under ultrasound-guided peripheral nerve blocks in critical peripheral artery disease (PAD) patients.
METHODS
We reviewed the medical records of consecutive patients who underwent major amputation at our center between December 2012 and December 2020. The patients' baseline demographics and comorbidities were collected. The primary outcomes were 30-day and 12-month mortality. The secondary outcomes were intraoperative events, complications and intensive care unit (ICU) admission.
RESULTS
Fifteen patients classified as American Society of Anesthesiologist (ASA) III and 13 ASA IV (mean age: 76.07 ± 11.78 years) were included in the study. These patients were critically ill and had many comorbidities, such as coronary artery disease. All amputations were successfully performed under ultrasound-guided PNB without conversion to GA, but intravenous analgesia was given in 7 patients during the operation. The majority of the patients had stable hemodynamics except for 2 patients who had hypoxia, so none of the patients were transferred to the ICU postoperatively. None of the patients suffered from acute cardio-cerebral events. However, 5 patients had wound infections, and 4 of 5 patients had to receive reamputation. None of the patients died within 48 h after amputation. However, the 30-day mortality was 3.57%, and the 12-month mortality was up to 35.71%.
CONCLUSION
This study demonstrates that major amputation could be safely and effectively performed under ultrasound-guided peripheral nerve blocks for critically ill patients, and ultrasound-guided peripheral nerve blocks could be an alternative for patients at high risk of general anesthesia or spinal anesthesia.
Topics: Humans; Middle Aged; Aged; Aged, 80 and over; Critical Illness; Peripheral Arterial Disease; Peripheral Nerves; Ultrasonography, Interventional; Amputation, Surgical
PubMed: 36039044
DOI: 10.1080/00015458.2022.2118985 -
Nature Methods Nov 2023We develop soft and stretchable fatigue-resistant hydrogel optical fibers that enable optogenetic modulation of peripheral nerves in naturally behaving animals during...
We develop soft and stretchable fatigue-resistant hydrogel optical fibers that enable optogenetic modulation of peripheral nerves in naturally behaving animals during persistent locomotion. The formation of polymeric nanocrystalline domains within the hydrogels yields fibers with low optical losses of 1.07 dB cm, Young's modulus of 1.6 MPa, stretchability of 200% and fatigue strength of 1.4 MPa against 30,000 stretch cycles. The hydrogel fibers permitted light delivery to the sciatic nerve, optogenetically activating hindlimb muscles in Thy1::ChR2 mice during 6-week voluntary wheel running assays while experiencing repeated deformation. The fibers additionally enabled optical inhibition of pain hypersensitivity in an inflammatory model in TRPV1::NpHR mice over an 8-week period. Our hydrogel fibers offer a motion-adaptable and robust solution to peripheral nerve optogenetics, facilitating the investigation of somatosensation.
Topics: Mice; Animals; Optical Fibers; Optogenetics; Hydrogels; Motor Activity; Sciatic Nerve; Locomotion
PubMed: 37857906
DOI: 10.1038/s41592-023-02020-9 -
International Journal of Biological... Dec 2023The incidence of peripheral nerve injury (PNI) is high worldwide, and a poor prognosis is common. Surgical closure and repair of the affected area are crucial to ensure...
The incidence of peripheral nerve injury (PNI) is high worldwide, and a poor prognosis is common. Surgical closure and repair of the affected area are crucial to ensure the effective treatment of peripheral nerve injuries. Despite being the standard treatment approach, reliance on sutures to seal the severed nerve ends introduces several limitations and restrictions. This technique is intricate and time-consuming, and the application of threading and punctate sutures may lead to tissue damage and heightened tension concentrations, thus increasing the risk of fixation failure and local inflammation. This study aimed to develop easily implantable chitosan-based peripheral nerve repair conduits that combine acrylic acid and cleavable N-hydroxysuccinimide to reduce nerve damage during repair. In ex vivo tissue adhesion tests, the conduit achieved maximal interfacial toughness of 705 J m ± 30 J m, allowing continuous bridging of the severed nerve ends. Adhesive repair significantly reduces local inflammation caused by conventional sutures, and the positive charge of chitosan disrupts the bacterial cell wall and reduces implant-related infections. This promises to open new avenues for sutureless nerve repair and reliable medical implants.
Topics: Humans; Peripheral Nerve Injuries; Chitosan; Adhesives; Sutureless Surgical Procedures; Inflammation; Nerve Regeneration; Peripheral Nerves
PubMed: 37709238
DOI: 10.1016/j.ijbiomac.2023.126793 -
Anesthesiology Dec 2023Continuous nerve block with ropivacaine is commonly performed after repair surgery for traumatic peripheral nerve injuries. After peripheral nerve injury,...
BACKGROUND
Continuous nerve block with ropivacaine is commonly performed after repair surgery for traumatic peripheral nerve injuries. After peripheral nerve injury, tetrodotoxin-resistant voltage-gated sodium channel Nav1.8 is upregulated and contributes to macrophage inflammation. This study investigated whether ropivacaine promotes peripheral nerve regeneration through Nav1.8-mediated macrophage signaling.
METHODS
A sciatic nerve transection-repair (SNT) model was established in adult Sprague-Dawley rats of both sexes. The rats received 0.2% ropivacaine or 10 μM Nav1.8-selective inhibitor A-803467 around the injured site or near the sacrum for 3 days. Nerve regeneration was evaluated using behavioral, electrophysiologic, and morphological examinations. Moreover, myelin debris removal, macrophage phenotype, Nav1.8 expression, and neuropeptide expression were assessed using immunostaining, enzyme-linked immunosorbent assay, and Western blotting.
RESULTS
Compared to the SNT-plus-vehicle group, the sensory, motor, and sensory-motor coordination functions of the two ropivacaine groups were significantly improved. Electrophysiologic (mean ± SD: recovery index of amplitude, vehicle 0.43 ± 0.17 vs. ropivacaine 0.83 ± 0.25, n = 11, P < 0.001) and histological analysis collectively indicated that ropivacaine significantly promoted axonal regrowth (percentage of neurofilament 200 [NF-200]-positive area: vehicle 19.88 ± 2.81 vs. ropivacaine 31.07 ± 2.62, n = 6, P < 0.001). The authors also found that, compared to the SNT-plus-vehicle group, the SNT-plus-ropivacaine group showed faster clearance of myelin debris, accompanied by significantly increased macrophage infiltration and transition from the M1 to M2 phenotype. Moreover, ropivacaine significantly attenuated Nav1.8 upregulation at 9 days after sciatic nerve transection (vehicle 4.12 ± 0.30-fold vs. ropivacaine 2.75 ± 0.36-fold, n = 5, P < 0.001), which coincided with the increased expression of chemokine ligand 2 and substance P. Similar changes were observed when using the selective Nav1.8 channel inhibitor A-803467.
CONCLUSIONS
Continuous nerve block with ropivacaine promotes the structural and functional recovery of injured sciatic nerves, possibly by regulating Nav1.8-mediated macrophage signaling.
Topics: Male; Female; Rats; Animals; Ropivacaine; Rats, Sprague-Dawley; Peripheral Nerve Injuries; Axons; Nerve Regeneration; Sciatic Nerve; Macrophages
PubMed: 37669448
DOI: 10.1097/ALN.0000000000004761 -
The Journal of Hand Surgery, European... Jun 2024Distal nerve transfer is a refined surgical technique involving the redirection of healthy sacrificable nerves from one part of the body to reinstate function in another... (Review)
Review
Distal nerve transfer is a refined surgical technique involving the redirection of healthy sacrificable nerves from one part of the body to reinstate function in another area afflicted by paralysis or injury. This approach is particularly valuable when the original nerves are extensively damaged and standard repair methods, such as direct suturing or grafting, may be insufficient. As the nerve coaptation is close to the recipient muscles or skin, distal nerve transfers reduce the time to reinnervation. The harvesting of nerves for transfer should usually result in minimal or no donor morbidity, as any anticipated loss of function is compensated for by adjacent muscles or overlapping cutaneous territory. Recent years have witnessed notable progress in nerve transfer procedures, markedly enhancing the outcomes of upper limb reconstruction for conditions encompassing peripheral nerve, brachial plexus and spinal cord injuries.
Topics: Humans; Nerve Transfer; Peripheral Nerve Injuries; Brachial Plexus; Upper Extremity
PubMed: 38296247
DOI: 10.1177/17531934231226169