Traumatic Peripheral Nerve Lesions Research Articles

Modern Instrumental Methods of Diagnosis of Traumatic Lesions of Peripheral Nerves

Damage to the peripheral nervous system is a serious medical and social problem due to high disability and high economic losses. To improve the results of treatment, an accurate diagnosis of the degree and level of nerve damage is necessary. This article reveals all modern instrumental methods for the diagnosis of traumatic injuries of the peripheral nervous system: electroneuromyography, ultrasound, magnetic resonance imaging. The advantages and disadvantages of each method are described.

Diagnostik von peripheren Nerven bei Läsionen und Kompressionssyndromen: Positionspaper der Deutschsprachigen Arbeitsgemeinschaft für Mikrochirurgie – (DAM)

The treatment of peripheral nerve pathologies requires a rapid and precise diagnosis. However, the correct identification of nerve pathologies is often difficult and valuable time is lost in the process. In this position paper of the German-Speaking Group for Microsurgery of Peripheral Nerves and Vessels (DAM), we describe the current evidence for various perioperative diagnostics for the detection of traumatic peripheral nerve lesions or compression syndromes. In detail, we evaluated the importance of clinical examinations, electrophysiology, nerve ultrasound and magnetic resonance neurography. Additionally, we surveyed our members for their diagnostic approach in this regard. The statements are based on a consensus workshop on the 42nd meeting of the DAM in Graz, Austria.

Clinical Considerations on Nerve Regenerative Techniques: a Commentary on the Article “Mesenchymal Stem Cell Treatment Perspectives in Peripheral Nerve Regeneration: Systematic Review”

Traumatic lesions of peripheral nerves affect hundreds of thousands of patients every year. The consequences are often devastating mainly because nerves spontaneous recovery is frequently inadequate. Cell therapy is one of the most innovative approaches in the field of nerve repair therapies.

The Role Of High Resolution Ultrasonography In Evaluation Of Post Traumatic Peripheral Nerve Injury

Background: With the development of scientific technology, applications of high-resolution ultrasound have rapidly developed in biomedical fields. High-resolution sonography clearly depicts peripheral nerve size spaces occupying lesions and anatomic variants along the entire length of the normative nerve Aim; Assessment of efficacy of ultrasound in evaluation of degree of traumatic nerve injury methods This prospective study was carried out during the period from June 2019 to April 2020 and included a hundred participants. All patients were referred to the radiology department of Benha university from the emergency department and outpatient clinic of surgery department of Benha university hospital. Results: diagnosis and characterization of turmeric peripheral nerve injury using ultrasound Conclusion; US can be used to facilitate the preoperative diagnosis and planning of the optimal treatment strategy as it can permit tracing the injured nerve at the lesion site and the neuroma’s extension. Finally, US has high accuracy for detection, diagnosis, assessment and treatment planning of traumatic peripheral nerve lesions.

Mesenchymal Stem Cell Treatment Perspectives in Peripheral Nerve Regeneration: Systematic Review.

Traumatic peripheral nerve lesions affect hundreds of thousands of patients every year; their consequences are life-altering and often devastating and cause alterations in movement and sensitivity. Spontaneous peripheral nerve recovery is often inadequate. In this context, nowadays, cell therapy represents one of the most innovative approaches in the field of nerve repair therapies. The purpose of this systematic review is to discuss the features of different types of mesenchymal stem cells (MSCs) relevant for peripheral nerve regeneration after nerve injury. The published literature was reviewed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A combination of the keywords “nerve regeneration”, “stem cells”, “peripheral nerve injury”, “rat”, and “human” were used. Additionally, a “MeSH” research was performed in PubMed using the terms “stem cells” and “nerve regeneration”. The characteristics of the most widely used MSCs, their paracrine potential, targeted stimulation, and differentiation potentials into Schwann-like and neuronal-like cells are described in this paper. Considering their ability to support and stimulate axonal growth, their remarkable paracrine activity, their presumed differentiation potential, their extremely low immunogenicity, and their high survival rate after transplantation, ADSCs appear to be the most suitable and promising MSCs for the recovery of peripheral nerve lesion. Clinical considerations are finally reported.

Contribution of ultrasonography in evaluating traumatic lesions of the peripheral nerves

To assess the indications for and utility of diagnostic ultrasonography (US) in a series of consecutive patients with suspected traumatic peripheral nerve lesions (TPNL). We retrospectively reviewed the electronic medical records of consecutive patients referred from February 2013 to May 2018 to our US laboratory. All included patients were examined using standard US equipment, with a 4-13MHz linear array transducer. In the analyzed period, we performed US examinations in 143 patients with 149 suspected TPNL. Electrodiagnostically (EDx) complete TPNL were found in 63 (45%), partial in 59 (42%), and only demyelination (i.e., neurapraxia) in four (3%) patients. TPNL could not be confirmed in 14 (10%) patients. Nerve discontinuity was not demonstrated by US in any of the patients with EDx incomplete nerve lesions. Contact of the nerve with osteosynthetic material (OSM) was found in eight of 33 patients (24%). In five patients, the nerve could not be adequately evaluated throughout its course due to extensive changes in the surrounding tissues. In acute situations, US is most useful in EDx complete TPNL to differentiate between nerve axonotmesis and neurotmesis. High-velocity trauma, lacerations, and bone fractures are all risk factors for neurotmesis. In chronic situations, US is useful in cases of functionally inefficient reinnervation, neuropathic pain, or progressive nerve dysfunction. In such patients, the surrounding tissues and the relation of the nerve to any OSM need to be carefully examined. US examination is probably not needed in patients with TPNL following acute blunt trauma, only minor clinical deficits and/or slightly/moderately abnormal EDx findings.

Traumatic peripheral nerve lesions : Diagnosis and treatment

Traumatic peripheral nerve lesions affect patients of all age groups. They are associated with functional deficits that have severe consequences for affected patients and prolonged or permanent inability to work has socioeconomic relevance. In order to improve prognoses and achieve the best possible outcome an early diagnosis and competent knowledge of the correct approach and treatment strategies are essential. Unfortunately, nerve lesions are often not detected in time, so that surgical treatment can only be initiated after a delay. Because of the relatively high proportion of iatrogenic nerve lesions, aprofound knowledge of the optimal care of patients with peripheral nerve lesions is compulsory for every doctor who works in the operative field. Surgical treatment of peripheral nerve lesions should remain in the hands of experienced peripheral nerve surgeons. The foundation of successful treatment, however, begins earlier at the initial referral when the patient receives the correct diagnostics and treatment.

Fascicular Ratio Pilot Study: High-Resolution Neurosonography-A Possible Tool for Quantitative Assessment of Traumatic Peripheral Nerve Lesions Before and After Nerve Surgery.

Clinical and electrophysiological assessments prevail in evaluation of traumatic nerve lesions and their regeneration following nerve surgery in humans. Recently, high-resolution neurosonography (HRNS) and magnetic resonance neurography have gained significant importance in peripheral nerve imaging. The use of the grey-scale-based "fascicular ratio" (FR) was established using both modalities allowing for quantitative assessment. To find out whether FR using HRNS can assess nerve trauma and structural reorganization in correlation to postoperative clinical development. Retrospectively, 16 patients with operated traumatic peripheral nerve lesions were included. The control group consisted of 6 healthy volunteers. All imaging was performed with a 15 to 6 MHz ultrasound probe (SonoSite X-Porte; Fujifilm, Tokyo, Japan). FR was calculated using Fiji () on 8-bit-images ("MaxEntropy" using "Auto-Threshold" plug-in). Thirteen of 16 patients required autologous nerve grafting and 3 of 16 extra-intraneural neurolysis. There was no statistical difference between the FR of nonaffected patients' nerve portion with 43.48% and controls with FR 48.12%. The neuromatous nerve portion in grafted patients differed significantly with 85.05%. Postoperatively, FR values returned to normal with a mean of 39.33%. In the neurolyzed patients, FR in the affected portion was 78.54%. After neurolysis, FR returned to healthy values (50.79%). Ten of 16 patients showed clinical reinnervation. To our best knowledge, this is the first description of FR using HRNS for quantitative assessment of nerve damage and postoperative structural reorganization. Our results show a significant difference in healthy vs lesioned nerves and a change in recovering nerve portions towards a more "physiological" ratio. Further evaluation in larger patient groups is required.

Clinical and instrumental characteristics of traumatic lesions of peripheral nerves of limbs

Traumatic injuries of peripheral nerves are caused by domestic, iatrogenic, industrial or military injuries. The estimated frequency of traumatic neuropathies in peacetime in Europe is 1 per 1000, with the highest prevalence among young people of working age. In modern local armed conflicts, the frequency and severity of gunshot injuries increased significantly. In connection with the widespread use of personal protective equipment (helmet, body armor), there is a relative increase in injuries to the limbs. Damage to the peripheral nerve can significantly reduce the patient’s quality of life and lead to severe disability with significant social and personal consequences. A deep understanding of the pathophysiology and molecular basis of damage to the peripheral nerves, achievements in the field of damage topography contributed to the development of microsurgical techniques of treatment. At the same time, there are quite a lot of unresolved issues related to clarifying the mechanisms of degeneration and regeneration in traumatic injuries of peripheral nerves. To determine and select a further tactic for the treatment of traumatic neuropathy, it is necessary to clarify the level, nature and severity of nerve damage. In order to improve the treatment of peripheral nerve injuries, in addition to the clinical-neurological examination, a wide range of additional modern instrumental research techniques are used: electroneuromyography, ultrasound investigation, magnetic resonance tomography.

P230 Ulnar epineural discontinuity and electrophysiological changes in a young girl following ulnar fracture

Objectives Electrophysiologic evaluation of traumatic peripheral nerve lesions can be complicated, especially in children where the given diagnosis can have dire consequences especially if not accurate. Method electrophysiological and sonographic consecutive examinations during a timelapse of 2 years (4 examinations). Results A 10 year old girl developed a severe ulnar neuropathy following a fracture of both forearm bones. Electrophysiology resembled complete denervation without any motoric or sensory answers. EMG revealed spontaneous activity in the interosseous dorsalis 1 muscle in the affected arm. Sonography visualized the nerve with an epineural defect but in continuity. We followed the girl in a timespace over 2 years with a total of 4 examinations. As the epineural defect diminished the electrophysiologic changes recovered. At the 4 examination the sonographic appearance was normalized except a slight neuroma at the lesion site. Discussion Decision making following traumatic nerve lesions relies heavily on electrodiagnostic testing. In this case we have shown that an epineural defect can “mimick” nerve discontinuity electrophysiologic. Sonography revealed the nerve in continuity and the nerve function slowly regained following the recovery of the epineurium. Conclusions Epineural defects can have an electrophysiological appearance resembling complete denervation in the recovery period. If sonography shows nerve continuity a conservative approach could be recommended. Significance Sonography can help along with electrophysiology in differentiating between severed nerves and nerve changes electrophysiologically resembling complete denervation. The case could argue that sonography should be performed in all traumatic nerve lesions.

Nerve injuries and traumatic lesions of the brachial plexus : Imaging diagnostics and therapeutic options

Traumatic lesions of peripheral nerves and the brachial plexus are feared complications because they frequently result in severe functional impairment. The prognosis is greatly dependent on the correct early diagnosis and the right choice of treatment regimen. It is important to distinguish between open and closed injuries. Initial imaging must critically evaluate or prove nerve continuity and is commonly achieved by high-resolution ultrasonography. During the further course, reactive soft tissue alterations, such as constrictive scarring or neuroma formation can be detected. In the case of deep nerve and plexus injuries this can be excellently achieved by dedicated magnetic resonance neurography (MRN) sequences. The signal yield from brachial plexus imaging can be critically enhanced by the use of dedicated surface coil arrays. Furthermore, diffusion tensor imaging (DTI) may enable the regeneration potential of anerve lesion to be recognized in the future. Multiple reports have shown that neurosonography enables a precise evaluation of peripheral nerve structures (up to 90% sensitivity and 95% specificity in nerve transection) and that the method can critically impact on therapeutic decision-making in 60%. Currently, there are only few quantitative data on the exact performance of MRN in traumatic nerve lesions; however, individual reports indicate a high level of agreement with intraoperative findings. In the initial work-up, especially in the case of peripheral, superficial and lesser nerve injuries, neurosonography is the preferred imaging approach to evaluate nerve integrity and the extent of nerve lesions. In the case of extensive nerve injury of proximal nerves and structures of the plexus as well as in the case of suspected root avulsion MRN is the method of choice.

Hierarchically structured nerve guidance channels based on poly-3-hydroxybutyrate enhance oriented axonal outgrowth

Traumatic peripheral nerve lesions can cause local anesthesia, paralysis and loss of autonomic control. Reconstruction using engineered nerve guidance conduits (NGCs) is rarely successful due to the sub-optimal characteristics of the conduits. To address the demands of clinical practice, we developed a hierarchically structured NGC from slowly resorbing poly(3-hydroxybutyric acid) (P3HB). The NGC consists of a permeable single-lumen tube and melt-spun fibrillar lumen fillers. Permeable tubes were constructed from P3HB/poly(ɛ-caprolactone) (PCL) blends or poly(3-hydroxybutyric acid-co-4-hydroxybutyric acid) (P(3HB-co-4HB)). Polyvinylpyrrolidone was used as a porogen in solvent-free thermoplastic processing, followed by selective polymer leaching. All tested material compositions showed hydrolytic degradation after 16weeks in phosphate buffered saline, whereas P3HB/PCL tubes maintained mechanical strength compared to (P(3HB-co-4HB)). The porous scaffolds allowed diffusion of large molecules (∼70kDa). In vitro studies demonstrated that mouse fibroblasts survived and proliferated inside closed porous tubes. An in vitro model of axonal regeneration using dorsal root ganglia and sympathetic cervical ganglia demonstrated that the NGCs successfully supported neuron survival and neurite outgrowth. The introduction of fibrillar lumen fillers promoted oriented neurite growth and coating with extracellular matrix proteins further increased ganglia attachment and cell migration. In this study we show that P3HB-based NGCs scaffolds have potential in long gap peripheral nerve repair strategies.

Intraoperative high-resolution ultrasound: a new technique in the management of peripheral nerve disorders

Surgical treatment of nerve lesions in continuity remains difficult, even in the most experienced hands. The regenerative potential of those injuries can be evaluated by intraoperative electrophysiological studies and/or intraneural dissection. The present study examines the value of intraoperative high-frequency ultrasound as an imaging tool for decision making in the management of traumatic nerve lesions in continuity. Intraoperative high-frequency ultrasound was applied to 19 traumatic or iatrogenic nerve lesions of differing extents. The information obtained was correlated with intraoperative electrophysiological, microsurgical intraneural dissection, and histopathological findings in resected nerve segments. The intraoperative application of high-resolution, high-frequency ultrasound enabled morphological examination of nerve lesions in continuity, with good image quality. The assessment of the severity of the underlying nerve injury matched perfectly with the judgment obtained from intraoperative electrophysiological studies. Both intraneural nerve dissection and neuropathological examination of the resected nerve segments confirmed the sonographic findings. In addition, intraoperative ultrasound proved to be very time efficient. With intraoperative ultrasound, the extent of traumatic peripheral nerve lesions can be examined morphologically for the first time. It is a promising, noninvasive method that seems capable of assessing the type (intraneural/perineural) and grade of nerve fibrosis. Therefore, in combination with intraoperative neurophysiological studies, intraoperative high-resolution ultrasound may represent a major tool for noninvasive assessment of the regenerative potential of a nerve lesion.

Traumatic Neuropathies: Spectrum of Imaging Findings and Postoperative Assessment

Traumatic injury to peripheral nerves is a significant cause of morbidity and disability. Until reinnervation occurs, electrodiagnostic studies cannot differentiate severe axonotmetic lesions (Sunderland class 4) from complete nerve transection or neurotmesis (Sunderland class 5). This limitation is relevant clinically because in cases of neurotmesis an improved outcome may be achieved with an early surgical repair (within 1 week after trauma). High-resolution ultrasound (US) is an efficient modality to visualize injured nerves and is becoming increasingly important among radiologists and surgeons. Magnetic resonance (MR) imaging is complementary to high-resolution US, especially in evaluating deep-seated and proximal nerve segments. This article describes the imaging features of traumatic peripheral nerve lesions. The role of diagnostic imaging in stretching injuries, contusion trauma, penetrating wounds, and after surgery is discussed. A multimodality diagnostic approach including physical examination, electrophysiology, and US and MR imaging allows an accurate evaluation of most peripheral nerves. Imaging assessment of peripheral nerves trauma is useful for the diagnosis, follow-up, and postoperative evaluation.

397 Effects of traumatic and selective chemical lesions of peripheral nerves on TRPV1 receptor expression: Implications for vanilloid-induced analgesia

397 Effects of traumatic and selective chemical lesions of peripheral nerves on TRPV1 receptor expression: Implications for vanilloid-induced analgesia

A Prospective Clinical Evaluation of Biodegradable Neurolac Nerve Guides for Sensory Nerve Repair in the Hand

Our purpose was to study the recovery of sensory nerve function after treatment of traumatic peripheral nerve lesions with a biodegradable poly(DL-lactide-epsilon-caprolactone) Neurolac nerve guide (Polyganics B.V., Groningen, the Netherlands) versus the current standard reconstruction techniques. Thirty patients with 34 nerve lesions were included in this randomized, multicenter trial. Both groups were comparable considering their demographics. After a small learning curve the nerve guide could be implanted easily. There were more complications in the experimental group but none of them was directly device related. Recovery of sensibility in the nerve guide group was at least as good as in the control group. These results indicate that the Neurolac nerve guide is suitable for the repair of transected peripheral nerves in the hand.

Magnetic Resonance Neurography of Peripheral Nerve Lesions in the Lower Extremity

We describe the clinical application and utility of high-resolution magnetic resonance neurography (MRN) techniques to image the normal fascicular structure of peripheral nerves and its distortion by mass lesions or trauma in the lower extremity. MRN images were obtained using a standard 1.5 Tesla magnet and custom built phased-array coils. Patients were imaged using T1-weighted spin echo without and with gadolinium, T2-weighted fast spin echo with fat peripheral nerve tumors (three neurofibromas and one schwannoma), two with intraneural cysts, and three with traumatic peripheral nerve lesions. Six patients with peripheral nerve mass lesions underwent surgery, thereby allowing MRN images to be correlated with intraoperative and pathological findings. Preoperative MRN accurately imaged the normal fascicular anatomy of peripheral nerves and precisely depicted its relation to tumor and cystic lesions. Increased signal on T2-weighted fast spin-echo and short tau inversion recovery fast spin-echo pulse sequences was seen in the peripheral nerve fascicles of patients with clinical and electrodiagnostic evidence of nerve injury. MRN proved useful in the preoperative evaluation and planning of surgery in patients with peripheral nerve lesions.

Internal Neurolysis in Traumatic Peripheral Nerve Lesions in Continuity

Internal neurolysis — the division of interfascicular scar tissue in order to relieve instrinsic axonal compression — has proved to be of value only in nerve lesions in continuity. There may be division of the axons with preservation of the continuity of connective tissue elements, or both the axons and connective tissue elements may remain intact but with failure of conduction as a result of injury. The authors’ procedure is described, from initial evaluation and diagnosis to surgical techniques. Case reports illustrate the types of lesions in which the procedure is of benefit.

Internal neurolysis in treatment of traumatic peripheral nerve lesions

Many peripheral nerve injuries are of a contusing type with resultant intraneural scarring which causes neurologic deficit even though the nerve is still in continuity. Internal neurolysis can relieve pain and restore neurologic function in such lesions. It is important that such lesions be recognized early, fully evaluated and carefully followed so that surgical intervention can be carried out before permanent changes can develop in the denervated muscles, joints and skin. The procedure is frequently rewarded with prompt and gratifying results. The risk is minimal and the patient need spend only a short time in hospital.