Peripheral Nerve Injuries in Sport

Sports-related peripheral nerve injuries of the upper limb

Peripheral nerve injuries in athletes affect the upper limb more commonly than the lower limb. Common mechanisms include compression, traction, laceration, and ischemia. Specific sports can have unique mechanisms of injury and are more likely to be associated with certain neuropathies. Familiarity with these sport-specific variables and recognition of the common presentations of upper limb neuropathic syndromes are important in assessing an athlete with a suspected peripheral nerve injury. Evaluation may require imaging modalities and/or electrodiagnostic testing to confirm a nerve injury. In some cases, diagnostic injections may be needed to differentiate neuropathic versus musculoskeletal etiology. Early and accurate diagnosis is essential for treatment/management and increases the likelihood of a safe return-to-sport and avoidance of long-term functional consequences. Most nerve injuries can be treated conservatively, however, severe or persistent cases may require surgical intervention. This monograph reviews key diagnostic, management, and preventative strategies for sports-related peripheral nerve injuries involving the upper limb.

Nanoparticle-Facilitated Therapy: Advancing Tools in Peripheral Nerve Regeneration

Peripheral nerve injuries, arising from a diverse range of etiologies such as trauma and underlying medical conditions, pose substantial challenges in both clinical management and subsequent restoration of functional capacity. Addressing these challenges, nanoparticles have emerged as a promising therapeutic modality poised to augment the process of peripheral nerve regeneration. However, a comprehensive elucidation of the complicated mechanistic foundations responsible for the favorable effects of nanoparticle-based therapy on nerve regeneration remains imperative. This review aims to scrutinize the potential of nanoparticles as innovative therapeutic carriers for promoting peripheral nerve repair. This review encompasses an in-depth exploration of the classifications and synthesis methodologies associated with nanoparticles. Additionally, we discuss and summarize the multifaceted roles that nanoparticles play, including neuroprotection, facilitation of axonal growth, and efficient drug delivery mechanisms. Furthermore, we present essential considerations and highlight the potential synergies of integrating nanoparticles with emerging technologies. Through this comprehensive review, we highlight the indispensable role of nanoparticles in propelling advancements in peripheral nerve regeneration.

Traumatic peripheral nerve injuries: a classification proposal

BACKGROUND

Peripheral nerve injuries (PNIs) include several conditions in which one or more peripheral nerves are damaged. Trauma is one of the most common causes of PNIs and young people are particularly affected. They have a significant impact on patients' quality of life and on the healthcare system, while timing and type of surgical treatment are of the utmost importance to guarantee the most favorable functional recovery. To date, several different classifications of PNIs have been proposed, most of them focusing on just one or few aspects of these complex conditions, such as type of injury, anatomic situation, or prognostic factors. Current classifications do not enable us to have a complete view of this pathology, which includes diagnosis, treatment choice, and possible outcomes. This fragmentation sometimes leads to an ambiguous definition of PNIs and the impossibility of exchanging crucial information between different physicians and healthcare structures, which can create confusion in the choice of therapeutic strategies and timing of surgery.

MATERIALS

The authors retrospectively analyzed a group of 24 patients treated in their center and applied a new classification for PNI injuries. They chose (a) five injury-related factors, namely nerve involved, lesion site, nerve type (whether motor, sensory or mixed), surrounding tissues (whether soft tissues were involved or not), and lesion type-whether partial/in continuity or complete. An alphanumeric code was applied to each of these classes, and (b) four prognostic codes, related to age, timing, techniques, and comorbidities.

RESULTS

An alphanumeric code was produced, similar to that used in the AO classification of fractures.

CONCLUSIONS

The authors propose this novel classification for PNIs, with the main advantage to allow physicians to easily understand the characteristics of nerve lesions, severity, possibility of spontaneous recovery, onset of early complications, need for surgical treatment, and the best surgical approach.

LEVEL OF EVIDENCE

according to the Oxford 2011 level of evidence, level 2.

Development of 3D-Printed, Biodegradable, Conductive PGSA Composites for Nerve Tissue Regeneration

Nerve conduits are used to reconnect broken nerve bundles and provide protection to facilitate nerve regeneration. However, the low degradation rate and regeneration rate, as well as the requirement for secondary surgery are some of the most criticized drawbacks of existing nerve conduits. With high processing flexibility from the photo-curability, poly (glycerol sebacate) acrylate (PGSA) is a promising material with tunable mechanical properties and biocompatibility for the development of medical devices. Here, polyvinylpyrrolidone (PVP), silver nanoparticles (AgNPs), and graphene are embedded in biodegradable PGSA matrix. The polymer composites are then assessed for their electrical conductivity, biodegradability, three-dimensional-printability (3D-printability), and promotion of cell proliferation. Through the four-probe technique, it is shown that the PGSA composites are identified as highly conductive in swollen state. Furthermore, biodegradability is evaluated through enzymatic degradation and facilitated hydrolysis. Cell proliferation and guidance are significantly promoted by three-dimensional-printed microstructures and electrical stimulation on PGSA composites, especially on PGSA-PVP. Hence, microstructured nerve conduits are 3D-printed with PGSA-PVP. Guided cell growth and promoted proliferation are subsequently demonstrated by Schwann cell culture combined with electrical stimulation. Consequently, 3D-printed nerve conduits fabricated with PGSA composites hold great potential in nerve tissue regeneration through electrical stimulation.

Local vibration therapy promotes the recovery of nerve function in rats with sciatic nerve injury

OBJECTIVE

It has been reported that local vibration therapy can benefit recovery after peripheral nerve injury, but the optimized parameters and effective mechanism were unclear. In the present study, we investigated the effect of local vibration therapy of different amplitudes on the recovery of nerve function in rats with sciatic nerve injury (SNI).

METHODS

Adult male Sprague-Dawley rats were subjected to SNI and then randomly divided into 5 groups: sham group, SNI group, SNI + A-1 mm group, SNI + A-2 mm group, and SNI + A-4 mm group (A refers to the amplitude; n = 10 per group). Starting on the 7th day after model initiation, local vibration therapy was given for 21 consecutive days with a frequency of 10 Hz and an amplitude of 1, 2 or 4 mm for 5 min. The sciatic function index (SFI) was assessed before surgery and on the 7th, 14th, 21st and 28th days after surgery. Tissues were harvested on the 28th day after surgery for morphological, immunofluorescence and Western blot analysis.

RESULTS

Compared with the SNI group, on the 28th day after surgery, the SFIs of the treatment groups were increased; the difference in the SNI + A-2 mm group was the most obvious (95% confidence interval [CI]: [5.86, 27.09], P < 0.001), and the cross-sectional areas of myocytes in all of the treatment groups were improved. The G-ratios in the SNI + A-1 mm group and SNI + A-2 mm group were reduced significantly (95% CI: [-0.12, -0.02], P = 0.007; 95% CI: [-0.15, -0.06], P < 0.001). In addition, the expressions of S100 and nerve growth factor proteins in the treatment groups were increased; the phosphorylation expressions of ERK1/2 protein in the SNI + A-2 mm group and SNI + A-4 mm group were upregulated (95% CI: [0.03, 0.96], P = 0.038; 95% CI: [0.01, 0.94], P = 0.047, respectively), and the phosphorylation expression of Akt in the SNI + A-1 mm group was upregulated (95% CI: [0.11, 2.07], P = 0.031).

CONCLUSION

Local vibration therapy, especially with medium amplitude, was able to promote the recovery of nerve function in rats with SNI; this result was linked to the proliferation of Schwann cells and the activation of the ERK1/2 and Akt signaling pathways.

A Review of Upper Extremity Peripheral Nerve Injuries in Throwing Athletes

Peripheral nerve injuries in the upper extremities may be common in throwing athletes as the throwing motion places extreme stress on the dominant arm. The combination of extreme stress along with repetitive microtrauma from throwing uniquely places the throwing athlete at elevated risk of upper extremity peripheral nerve injury. However, because symptoms can be non-specific and frequent co-exist with pathology in the upper extremity, the diagnosis of peripheral nerve injury is often delayed. Diagnosis of peripheral nerve injuries may require a combination of history and physical exam, diagnostic imaging, electrodiagnostic testing, and diagnostic ultrasound guided injections. The primary management should include physical therapy focusing on throwing mechanics and kinetic chain evaluation. However, some athletes require surgical intervention if symptoms do not improve with conservative management. The purpose of this focused narrative review is to highlight upper extremity peripheral neuropathies reported in throwing athletes and to provide an overview of the appropriate clinical diagnosis and management of the throwing athlete with a peripheral nerve injury. This article is protected by copyright. All rights reserved.

Epidemiology of Peripheral Nerve Injuries in Sports, Exercise, and Recreation in the United States, 2009 - 2018

OBJECTIVE

To assess rates of peripheral nerve injuries (PNI) in sport, exercise, and recreational activities.

METHODS

The National Electronic Injury Surveillance System (NEISS) was used to query nerve injuries presenting to emergency departments across the United States. Identified injuries were stratified to those with product codes associated with exercise, sports, or recreation. Injuries only to the upper and lower extremities were included as cranial and spinal cord injuries were excluded. PNI was analyzed by age, sex, sport/recreational activity, race, and evaluated for incidence rates by year and activity. Statistical significance was considered to be P < 0.05.

RESULTS

Between 2009-2018, 551,612 patients presented with PNI from which 120,675 (21.9%) were associated with exercise, sports, or recreation. PNI significantly increased between 2009-2018 (p = 0.002) with an overall incidence rate of 36.9 (95% confidence interval: 28.6, 45.2) per 1,000,000 person-years. A majority of PNI occurred through exercise (n = 56,328, 46.7%). PNI peaked in the fourth and fifth decades in males and females, respectively, with males accounting for significantly more than females (incidence rate ratio: 1.52, 95% confidence interval: 1.18, 1.86; p < 0.0001). White patients had a majority of PNI at 49.3% though African-Americans carried the highest incidence rate at 30.4 (95% confidence interval: 23.8, 36.9) per 1,000,000 person-years. Football had the highest proportion of PNI until age 19 (17.3%) as exercise carried the highest proportion for those 20 and older ranging from 27.9% to 53.8% of PNI.

CONCLUSION

PNIs are rising with participation in exercise, sports, and recreation over this 10-year study period. Injuries predominantly occurred in football for those under 20 and exercise for those 20 and older. Precautions and appropriate training are necessary for individuals participating in high-intensity exercise, sports, or recreation to limit the risk of a devastating neurological injury.

Traumatic Injuries to the Spinal Cord and Peripheral Nervous System

Both blunt and penetrating trauma can cause injuries to the peripheral and central nervous systems. Emergency providers must maintain a high index of suspicion, especially in the setting of polytrauma. There are 2 major classifications of peripheral nerve injuries (PNIs). Some PNIs are classically associated with certain traumatic mechanisms. Most closed PNIs are managed conservatively, whereas sharp nerve transections require specialist consultation for urgent repair. Spinal cord injuries almost universally require computed tomography imaging; some require emergent magnetic resonance imaging. Providers should work to minimize secondary injury. Surgical specialists are needed for closed reduction, surgical decompression, or stabilization.

The progress of biomaterials in peripheral nerve repair and regeneration

Repair and regeneration of the injured peripheral nerve (PN) is a challenging issue in clinics. Although the regeneration outcome of large PN defects is currently unsatisfactory, recently, the study of PN repair has considerably progressed. In particular, biomaterials for repairing PNs, such as nerve guidance conduits and nerve repair membranes, have been well developed. Herein, we summarize the anatomy of the PN, the pathophysiological features of the nerve injury, and the repair process post injury. Then, we highlight the progress in the development of natural and synthetic biomaterials and summarize the applications, advantages, and disadvantages of these materials. These materials can be used as nerve repair membranes and nerve conduits in the field of PN repair. Finally, we discuss the challenges encountered and development strategies for PN repair in the future.

Anti-Apoptotic Mechanisms of Acupuncture in Neurological Diseases: A Review

Apoptosis, known as programmed cell death, plays a significant role in the pathogenesis of neurological diseases. Most of these diseases can be obviously alleviated by means of acupuncture treatment. Current research studies have shown that the efficacy of acupuncture to these medical conditions is closely associated with the anti-apoptotic potentials. Mainly based on the acupuncture's anti-apoptotic efficacy in prevalent neurological disorders, including cerebral ischemia-reperfusion injury, Alzheimer's disease, depression or stress related-modes, spinal cord injuries, etc., this review comes to a conclusion that the anti-apoptotic effect of acupuncture treatment for neurological diseases, evidently reflected through Bcl-2, Bax or caspase expression change, results from regulating mitochondrial or autophagic dysfunction as well as reducing oxidative stress and inflammation. The possible mechanisms of acupuncture's anti-apoptotic effect are associated with a series of downstream signaling pathways and the up-regulated expression of neurotrophic factors. It is of great importance to illuminate the exact mechanisms of acupuncture treatment for neurological dysfunctions.