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Radiographics : a Review Publication of... 2016Ultrasonography (US) is commonly used to assess the peripheral nerves of the lower extremity because of its many advantages over magnetic resonance (MR) imaging. The... (Review)
Review
Ultrasonography (US) is commonly used to assess the peripheral nerves of the lower extremity because of its many advantages over magnetic resonance (MR) imaging. The most obvious advantages over MR imaging are superior soft-tissue resolution, low cost, portability, lack of magnetic susceptibility artifact, and the ability to image patients who cannot undergo MR imaging. US has been shown to have equal specificity and greater sensitivity than MR imaging in the evaluation of peripheral nerves. Additional benefits are the capability of real-time and dynamic imaging, and the ability to scan an entire extremity quickly without the need for a patient to lie motionless for long periods of time, as with MR imaging. Any abnormal findings can be easily compared against the contralateral side. Published literature has shown that US has clinical utility in patients suspected of having peripheral nerve disease: US can be used to guide diagnostic and therapeutic decisions, as well as help confirm electrodiagnostic findings. Common indications for lower extremity peripheral nerve US are the evaluation for injury due to penetrating trauma, entrapment by scar tissue, or tumor. To confidently perform US of the peripheral nerves of the lower extremity, it is important to gain a thorough knowledge of anatomic landmarks and the course of each nerve. Readers who may not be familiar with US will be introduced to the basics of scanning the peripheral nerves of the lower extremity. Important anatomic landmarks and common sites of injury and entrapment will be reviewed.
Topics: Femoral Nerve; Humans; Leg; Magnetic Resonance Imaging; Morton Neuroma; Peripheral Nerve Injuries; Peripheral Nerves; Peripheral Nervous System Diseases; Peroneal Nerve; Sciatic Nerve; Tibial Nerve; Ultrasonography
PubMed: 26871986
DOI: 10.1148/rg.2016150120 -
Journal of Visualized Experiments : JoVE Oct 2021Peripheral nerve interfaces are frequently used in experimental neuroscience and regenerative medicine for a wide variety of applications. Such interfaces can be...
Peripheral nerve interfaces are frequently used in experimental neuroscience and regenerative medicine for a wide variety of applications. Such interfaces can be sensors, actuators, or both. Traditional methods of peripheral nerve interfacing must either tether to an external system or rely on battery power that limits the time frame for operation. With recent developments of wireless, battery-free, and fully implantable peripheral nerve interfaces, a new class of devices can offer capabilities that match or exceed those of their wired or battery-powered precursors. This paper describes methods to (i) surgically implant and (ii) wirelessly power and control this system in adult rats. The sciatic and phrenic nerve models were selected as examples to highlight the versatility of this approach. The paper shows how the peripheral nerve interface can evoke compound muscle action potentials (CMAPs), deliver a therapeutic electrical stimulation protocol, and incorporate a conduit for the repair of peripheral nerve injury. Such devices offer expanded treatment options for single-dose or repeated dose therapeutic stimulation and can be adapted to a variety of nerve locations.
Topics: Animals; Electric Power Supplies; Electric Stimulation Therapy; Peripheral Nerves; Phrenic Nerve; Prostheses and Implants; Rats; Wireless Technology
PubMed: 34747395
DOI: 10.3791/63085 -
Tissue Engineering. Part B, Reviews Apr 2022Reconstruction of peripheral nerve injuries (PNIs) with substance loss remains challenging because of limited treatment solutions and unsatisfactory patient outcomes.... (Review)
Review
Reconstruction of peripheral nerve injuries (PNIs) with substance loss remains challenging because of limited treatment solutions and unsatisfactory patient outcomes. Currently, nerve autografting is the first-line management choice for bridging critical-sized nerve defects. The procedure, however, is often complicated by donor site morbidity and paucity of nerve tissue, raising a quest for better alternatives. The application of other treatment surrogates, such as nerve guides, remains questionable, and it is inefficient in irreducible nerve gaps. More importantly, these strategies lack customization for personalized patient therapy, which is a significant drawback of these nerve repair options. This negatively impacts the fascicle-to-fascicle regeneration process, critical to restoring the physiological axonal pathway of the disrupted nerve. Recently, the use of additive manufacturing (AM) technologies has offered major advancements to the bioengineering solutions for PNI therapy. These techniques aim at reinstating the native nerve fascicle pathway using biomimetic approaches, thereby augmenting end-organ innervation. AM-based approaches, such as three-dimensional (3D) bioprinting, are capable of biofabricating 3D-engineered nerve graft scaffolds in a patient-specific manner with high precision. Moreover, realistic models of peripheral nerve tissues that represent the physiologically and functionally relevant environment of human organs could also be developed. However, the technology is still nascent and faces major translational hurdles. In this review, we spotlighted the clinical burden of PNIs and most up-to-date treatment to address nerve gaps. Next, a summarized illustration of the nerve ultrastructure that guides research solutions is discussed. This is followed by a contrast of the existing bioengineering strategies used to repair peripheral nerve discontinuities. In addition, we elaborated on the most recent advances in 3D printing and biofabrication applications in peripheral nerve modeling and engineering. Finally, the major challenges that limit the evolution of the field along with their possible solutions are also critically analyzed. Impact statement Complex nerve injuries, including critical-sized gaps (>3 cm loss of substance), gaps involving nerve bifurcations, and those associated with ischemic environments, are difficult to manage. A biomimetic, personalized peripheral nerve tissue surrogate to address these injuries is lacking. The peripheral nerve repair market currently represents a multi-billion-dollar industry that is projected to expand. Given the clinical and economical dilemmas posed by this medical condition, it is crucial to devise novel and effective nerve substitutes. In this review article, we discuss progress in three-dimensional printing technologies, including biofabrication and nerve computer-aided design modeling, toward achieving a patient-specific and biomimetic nerve repair solution.
Topics: Bioprinting; Humans; Nerve Regeneration; Peripheral Nerve Injuries; Peripheral Nerves; Printing, Three-Dimensional
PubMed: 33593147
DOI: 10.1089/ten.TEB.2020.0355 -
Hand Clinics May 2016Manufactured conduits and allografts are viable alternatives to direct suture repair and nerve autograft. Manufactured tubes should have gaps less than 10 mm, and... (Review)
Review
Manufactured conduits and allografts are viable alternatives to direct suture repair and nerve autograft. Manufactured tubes should have gaps less than 10 mm, and ideally should be considered as an aid to the coaptation. Processed nerve allograft has utility as a substitute for either conduit or autograft in sensory nerve repairs. There is also a growing body of evidence supporting their utility in major peripheral nerve repairs, gap repairs up to 70 mm in length, as an alternative source of tissue to bolster the diameter of a cable graft, and for the management of neuromas in non-reconstructable injuries.
Topics: Allografts; Autografts; Biocompatible Materials; Guided Tissue Regeneration; Humans; Nerve Regeneration; Neurosurgical Procedures; Peripheral Nerve Injuries; Peripheral Nerves; Tissue Scaffolds; Tissue and Organ Harvesting; Transplantation, Autologous
PubMed: 27094886
DOI: 10.1016/j.hcl.2015.12.012 -
Neurosurgical Review Oct 2014Peripheral nerve repair for complete section injuries employ reconstructive techniques that invariably require sutures in their application. Sutures are unable to seal... (Review)
Review
Peripheral nerve repair for complete section injuries employ reconstructive techniques that invariably require sutures in their application. Sutures are unable to seal the nerve, thus incapable of preventing leakage of important intraneural fluids from the regenerating nerve. Furthermore, sutures are technically demanding to apply for direct repairs and often induce detrimental scarring that impedes healing and functional recovery. To overcome these limitations, biocompatible and biodegradable glues have been used to seal and repair peripheral nerves. Although creating a sufficient seal, they can lack flexibility and present infection risks or cytotoxicity. Other adhesive biomaterials have recently emerged into practice that are usually based on proteins such as albumin and collagen or polysaccharides like chitosan. These adhesives form their union to nerve tissue by either photothermal (tissue welding) or photochemical (tissue bonding) activation with laser light. These biomaterial adhesives offer significant advantages over sutures, such as their capacity to unite and seal the epineurium, ease of application, reduced invasiveness and add the potential for drug delivery in situ to facilitate regeneration. This paper reviews a number of different peripheral nerve repair (or reconstructive) techniques currently used clinically and in experimental procedures for nerve injuries with or without tissue deficit.
Topics: Biocompatible Materials; Humans; Neurosurgical Procedures; Peripheral Nerves; Sutures
PubMed: 25015388
DOI: 10.1007/s10143-014-0559-1 -
Life Sciences Aug 2018Peripheral nerve injury is one of the most common clinical diseases. Although the regeneration of the peripheral nerve is better than that of the nerves of the central... (Review)
Review
Peripheral nerve injury is one of the most common clinical diseases. Although the regeneration of the peripheral nerve is better than that of the nerves of the central nervous system, because of its growth rate restrictions after damage. Hence, the outcome of repair after injury is not favorable. Small RNA, a type of non-coding RNA, has recently been gaining attention in neural injury. It is widely distributed in the nervous system in vivo and a significant change in the expression of small RNAs has been observed in a neural injury model. This suggests that MicroRNAs (miRNAs) may serve as a potential target for resolving the challenges of peripheral nerve repair. This review summarizes the current challenges in peripheral nerve injury repair, systematically expounds the mechanism of miRNAs in the process of nerve injury and repair and attempts to determine the possible treatment of peripheral nerve injury.
Topics: Animals; Apoptosis; Axons; Cell Proliferation; Gene Silencing; Humans; Inflammation; MicroRNAs; Nerve Regeneration; Peripheral Nerve Injuries; Peripheral Nerves; Peripheral Nervous System; Schwann Cells
PubMed: 29894714
DOI: 10.1016/j.lfs.2018.06.011 -
Progress in Neurological Surgery 2015The number of peripheral nerve stimulation (PNS) indications, targets, and devices is expanding, yet the development of the technology has been slow because many devices... (Review)
Review
The number of peripheral nerve stimulation (PNS) indications, targets, and devices is expanding, yet the development of the technology has been slow because many devices used for PNS do not have formal regulatory approval. Manufacturers have not sought Food and Drug Administration (FDA) approval for PNS devices because of a perceived lack of interest amongst practitioners and patients. Without FDA approval, companies cannot invest in marketing to educate the implanters and the patients about the benefits of PNS in the treatment of chronic pain. Violation of this has resulted in governmental investigation and prosecution. Most of the PNS devices currently used to treat chronic pain are FDA approved for epidural spinal cord stimulation. Many of the complications seen in PNS surgery can be attributed to the lack of purpose-built hardware with FDA approval. Despite the lack of regulatory approval, there are insurance companies that approve PNS procedures when deemed medically necessary. As the targets and indications for PNS continue to expand, there will be an even greater need for customized technological solutions. It is up to the medical device industry to invest in the design and marketing of PNS technology and seek out FDA approval. Market forces will continue to push PNS into the mainstream and physicians will increasingly have the choice to implant devices specifically designed and approved to treat chronic peripheral nerve pain.
Topics: Device Approval; Electric Stimulation Therapy; Humans; Pain Management; Peripheral Nerves; United States
PubMed: 26394389
DOI: 10.1159/000434674 -
World Neurosurgery Mar 2023Peripheral nerve surgery in Serbia has become the most fruitful subsection of national neurosurgery, with international recognition of Serbian surgeons and institutions.... (Review)
Review
Peripheral nerve surgery in Serbia has become the most fruitful subsection of national neurosurgery, with international recognition of Serbian surgeons and institutions. We chronicle landmark events in the history of the field in Serbia, highlighting the development of the field over time and outlining future prospects. This manuscript provides an example of the development of peripheral nerve surgery and associated training in a challenging social, political, and economic context and may guide the development of peripheral nerve surgery care and training in other settings.
Topics: Humans; Serbia; Neurosurgical Procedures; Neurosurgery; Peripheral Nerves
PubMed: 36435386
DOI: 10.1016/j.wneu.2022.11.086 -
International Journal of Molecular... Aug 2020The peripheral nervous system controls the functions of sensation, movement and motor coordination of the body. Peripheral nerves can get damaged easily by trauma or... (Review)
Review
The peripheral nervous system controls the functions of sensation, movement and motor coordination of the body. Peripheral nerves can get damaged easily by trauma or neurodegenerative diseases. The injury can cause a devastating effect on the affected individual and his aides. Treatment modalities include anti-inflammatory medications, physiotherapy, surgery, nerve grafting and rehabilitation. 3D bioprinted peripheral nerve conduits serve as nerve grafts to fill the gaps of severed nerve bodies. The application of induced pluripotent stem cells, its derivatives and bioprinting are important techniques that come in handy while making living peripheral nerve conduits. The design of nerve conduits and bioprinting require comprehensive information on neural architecture, type of injury, neural supporting cells, scaffold materials to use, neural growth factors to add and to streamline the mechanical properties of the conduit. This paper gives a perspective on the factors to consider while bioprinting the peripheral nerve conduits.
Topics: Animals; Bioprinting; Humans; Induced Pluripotent Stem Cells; Peripheral Nerves; Printing, Three-Dimensional; Tissue Engineering; Tissue Scaffolds
PubMed: 32806758
DOI: 10.3390/ijms21165792 -
European Journal of Anaesthesiology Mar 2017Regarding nerves as simple cables and electrical conduits is a gross error that does not allow us to understand the anomalies and disorders observed postoperatively.... (Review)
Review
Regarding nerves as simple cables and electrical conduits is a gross error that does not allow us to understand the anomalies and disorders observed postoperatively. Instead, nerves should be seen as a living tissue of which physiological regulation is as complex as that of the blood-brain barrier. This review describes the basic structure and functions of this blood-nerve barrier and highlights the mechanisms of its breakdown and the resultant disorders. For clinical practice, it is important to note that the diffusion of molecules from the perineurium or from the blood is very limited, and so the blood-nerve barrier is a major pharmacologic barrier. Any stress upon neural physiological balance, particularly the terminal vascular blood supply, will induce the classic inflammatory cascade. Due to the complexity of the vascular system, nerve ischaemia will occur more quickly when the terminal blood supply is compromised. This blood supply can adapt in a variety of ways but when these possibilities of adaptation are exceeded, tissue ischaemia may be more extensive. Also, even after the initial injury has subsided, inflammation can cause a secondary insult. This could be particularly important in some patients with subclinical neuropathy.
Topics: Animals; Blood-Brain Barrier; Humans; Inflammation; Peripheral Nerve Injuries; Peripheral Nerves
PubMed: 28146457
DOI: 10.1097/EJA.0000000000000590