Radial nerve injuries from gunshot wounds and other trauma: comparison of electrodiagnostic findings

Gunshot-related nerve injuries of the upper extremities: clinical, electromyographic, and ultrasound features in 22 patients

Objectives

Gunshot wounds of the upper extremities may cause permanent neurovascular injuries, leading to significant morbidity, chronic pain, functional loss, and disability. While there are many reports on the incidence and intraoperative findings in gunshot-related nerve injuries (GSNI) sustained during wars, there is a paucity of details pertaining to GSNI of the upper extremities in civilians. The goal of this paper is to provide the clinical, electrodiagnostic (EDX), and ultrasound (US) findings in 22 patients with GSNI of the upper extremities.

Methods

This is a retrospective study of patients referred for EDX studies to evaluate the presence of nerve injury after sustaining GSWs to the upper extremities. All patients underwent EDX studies, and 16 patients had US evaluations. Numerous metrics were documented including presenting symptoms, neurological abnormalities, EDX findings, and US features.

Results

The forearm was the most frequent location of injury (8 [36%] patients). The ulnar nerve was the most common injured nerve (10 [45%] patients), followed by the brachial plexus (7 [32%] patients). All patients complained of muscle weakness; the most frequently affected muscles were the first dorsal interosseous (FDI) (14 [64%] patients) and abductor pollicis brevis (APB) (11 [50%] patients). Muscle atrophy was noted in 19 (86%) patients, 15 of whom had atrophy of the FDI. Axonotmesis was the type of nerve injury in all patients based on EDX studies. Of the 16 patients who underwent US studies, a neuroma in continuity was noted in 4 (25%) patients and neurotmesis in 1 (6.2%) patient. Eleven (69%) patients had enlarged and/or hypoechoic nerves.

Conclusions

Axonotmesis of the ulnar nerve was the most common finding among patients sustaining gunshot injuries to the upper extremities. EDX and US studies provide valuable insight into the underlying pathophysiology and guidance for management of patients with GSNI of the upper extremities.

Etiological and epidemiological characteristics of surgically treated radial nerve lesions: A 20-year single-center experience

Introduction

Radial nerve lesions present a clinical entity that may lead to disability, psychological distress, and job loss, and thus requires great attention. Knowledge of the etiology and exact mechanism of the nerve impairment is of great importance for appropriate management of these patients, and there are only a few papers that focused on these features in patients with surgically treated radial nerve lesions. The lack of studies presenting the etiology and injury mechanisms of surgically treated radial nerve lesions may be due to a relatively small number of specialized referral centers, dispersion to low-flow centers, and a greater focus on the surgical treatment outcomes.

Aim

The aim of this study was to describe the etiological and epidemiological characteristics of patients with surgically treated radial nerve lesions of various origins.

Methods

This retrospective study evaluated 147 consecutive patients with radial nerve lesion, treated in the department during the last 20 years, from January 1, 2001, until December 31, 2020.

Results

The majority of patients belonged to the working population, and 70.1% of them were male. Most commonly, the etiology of nerve lesion was trauma (63.3%) or iatrogenic injury (28.6%), while the less common origin was idiopathic (4.1%) or neoplastic (4.1%). The most frequent location of the lesion was in the upper arm, followed by the elbow and forearm. Fracture-related contusion was the most common mechanism (29.9%), followed by postoperative fibrosis (17.7%), lacerations (17.7%), and compression (15.6%).

Conclusion

Based on the fact that traumatic or iatrogenic injuries constitute the majority of cases, with their relevant mechanisms and upper arm predomination, it is crucial to raise awareness and understanding of the radial nerve injuries among orthopedic surgeons to decrease the numbers of these patients and properly preserve or treat them within the initial surgery.

Electrophysiologic Features of Radial Neuropathy in Childhood and Adolescence

BACKGROUND

We analyzed the clinical and electrophysiologic patterns of nerve injury in pediatric patients with radial neuropathy.

METHODS

This is a retrospective analysis of 19 children and adolescents with radial neuropathy.

RESULTS

The mean subject age was 12 years (range one month to 19 years), 56% were female, and 53% had traumatic etiologies. Weakness in the finger and wrist extensors was the prevailing complaint (82%). Predominant localization was at the posterior interosseous nerve (37%), followed by the radial nerve below the spiral groove (32%), the radial nerve at the spiral groove (26%), and the radial nerve above the spiral groove (5%). Extensor indicis proprius compound muscle action potential amplitude was reduced in 86% of cases when tested, with a median axon loss estimate of 78%. The radial sensory nerve action potential amplitude was reduced in 53% of all cases, and in 83% of cases affecting the main radial trunk with a median axon loss estimate of 100%. For neuropathy affecting the main radial trunk, there was a high correlation of extensor indicis proprius median axon loss estimate and radial sensory nerve action potential median axon loss estimate (r = 0.72, P = 0.02). Neurogenic changes were seen in the extensor indicis proprius, extensor digitorum communis, extensor carpi radialis, and brachioradialis in 88%, 94%, 60%, and 44% of cases, respectively. Pathophysiology was demyelinating in 10%, axonal in 58%, and mixed in 32%.

CONCLUSIONS

In contrast to adults, where localization at the spiral groove predominates, radial neuropathy in children and adolescents is commonly localized at the posterior interosseous nerve or at the distal main radial trunk. Pediatric radial neuropathy is frequently of traumatic etiology and axonal pathophysiology.

Radial nerve palsy

As a result of its proximity to the humeral shaft, as well as its long and tortuous course, the radial nerve is the most frequently injured major nerve in the upper limb, with its close proximity to the bone making it vulnerable when fractures occur.Injury is most frequently sustained during humeral fracture and gunshot injuries, but iatrogenic injuries are not unusual following surgical treatment of various other pathologies.Treatment is usually non-operative, but surgery is sometimes necessary, using a variety of often imaginative procedures. Because radial nerve injuries are the least debilitating of the upper limb nerve injuries, results are usually satisfactory.Conservative treatment certainly has a role, and one of the most important aspects of this treatment is to maintain a full passive range of motion in all the affected joints.Surgical treatment is indicated in cases when nerve transection is obvious, as in open injuries or when there is no clinical improvement after a period of conservative treatment. Different techniques are used including direct suture or nerve grafting, vascularised nerve grafts, direct nerve transfer, tendon transfer, functional muscle transfer or the promising, newer treatment of biological therapy. Cite this article: Bumbasirevic M, Palibrk T, Lesic A, Atkinson HDE. Radial nerve palsy. EFORT Open Rev 2016;1:286-294. DOI: 10.1302/2058-5241.1.000028.

Surgical repair of ulnar nerve lesions caused by gunshot and shrapnel: results in 407 lesions

Object

Ulnar nerve lesions caused by gunshot wounds have rarely been reported in the current literature. The authors describe the outcome after surgical repair of such injuries, and the factors influencing the results of treatment.

Methods

This retrospective study includes 455 patients with 462 ulnar nerve injuries caused by gunshot wounds who were treated at Gulhane Military Medical Academy over a 40-year period. A total of 407 ulnar lesions were surgically repaired at that institution between 1966 and 2005; 237 patients were injured by shrapnel and 218 patients by gunshot. The authors evaluated the motor, sensory, and electrophysiological recovery in these patients, as well as the patients' judgment of the outcome. The authors also tested the effect of repair level, nerve graft length, time to operation, repair technique used, and the presence of coexisting damages in the nerve repair region. The final outcome in these patients was defined as poor, fair, or good on the basis of the British Medical Research Council scores.

Results

A good outcome was noted in 15.06% of patients who underwent high-level repair, 29.60% of patients who underwent intermediate-level repair, and 49.68% of patients after low-level repair. On average, patients with successful outcomes had a significantly shorter time to operation than those with unsuccessful outcomes. The critical period for surgery was within 6 months of injury. Although the optimal graft length was found to be 5 cm, this finding was not statistically significant.

Conclusions

The reported outcome of repairs to ulnar nerves damaged by gunshot has varied in the literature, but there is a consensus that the duration of the interval to surgery, the repair level, and the graft length used influence the outcome of surgical repair for ulnar nerve lesions.

Importance of Electromyography and the Electrophysiological Severity Scale in Forensic Reports

Forensic reports on traumatic peripheral nerve injuries include dysfunction degrees of extremities, which are arranged according to the Turkish Penalty Code. The aim of this study is to discuss the role and importance of electromyography while preparing forensic reports in the cases of traumatic peripheral nerve injuries and the usefulness of scoring systems. A modified global scale, recommended by Mondelli et al., was used to assess the electrophysiological impairment of each peripheral nerve. Forensic reports of 106 patients, reported between 2002 and 2004, were evaluated. Thirty-four percent of the cases were reported as "total loss of function," 41.5% were reported as "functional disability," and there were no dysfunctions in the other cases in forensic reports that were prepared based on Council of Social Insurance Regulations of Health Processes and Guide prepared by the Council of Forensic Medicine and profession associations of forensic medicine. When we rearranged these forensic reports based on the electrophysiological severity scale (ESS), it was clearly found that all of the score 2 cases and 86.7% of the score 3 cases corresponded to "functional disability" and 91.4% of the score 4 cases correspond to "total loss of function." We found a significant correlation between the ESS and functional evaluation in peripheral nerve injury cases. Evaluation of functional disabilities in peripheral nerve injuries with the ESS represents a standardized and objective method used for forensic reports.

Prognostic values of electrodiagnostic studies in traumatic radial neuropathy

It is important to have strong predictors of outcome in traumatic neuropathies so that appropriate management can be instituted early. Our objective in this study was to evaluate the prognostic value of electrodiagnostic studies in traumatic radial neuropathy. In this retrospective study, 33 of 67 subjects with traumatic radial neuropathy met the inclusion criteria. Good outcome was defined as grade 3 or higher strength on the Medical Research Council scale in wrist extensors. Compound muscle action potential (CMAP) responses from extensor indicis proprius (EIP) predicted prognosis: 92% of subjects with a recordable CMAP had a good outcome; and 65% of those with an absent response had a good outcome. Recruitment in brachioradialis was also predictive: 92% of those with full, central, or reduced recruitment had a good outcome; 67% of those with discrete recruitment had a good outcome; and only 33% of those with absent recruitment had a good outcome. Studies performed more than 3 months after injury produced more prognostic certainty than those performed earlier. We conclude that electrodiagnostic studies produce useful prognostic information in traumatic radial neuropathy. It is noteworthy, however, that 65% of subjects with an absent radial CMAP (suggesting complete or nearly complete axon loss) still have a good outcome.

Difference in Recovery Potential of Peripheral Nerves after Graft Repairs

OBJECTIVE:

To our knowledge, few studies have been published regarding differences in nerve recovery potentials. In this study, sensory and motor recovery potentials were compared between different nerves.

METHODS:

A prospective study of a homogenous group of 393 graft repairs of the median, ulnar, radial, tibial, peroneal, femoral, and musculocutaneous nerves, with the scoring of motor and sensory recoveries. Sensory and motor recovery potentials, defined on the basis of average scores and rates of useful recovery, were compared between the different nerves, and separately for high-, intermediate-, and low-level repairs.

RESULTS:

Sensory recovery potential was similar for all nerves tested (P > 0.05), but motor recovery potential differed significantly. After high-level repairs, motor recovery potential was significantly better for the radial and tibial nerves (useful recovery in 66.7 and 54.5% of patients, respectively), than for the ulnar and peroneal nerves (useful recovery in 15.4 and 13.8% of patients, respectively; P < 0.05). After intermediate-level repairs, motor recovery potential was better for the musculocutaneous, radial, and femoral nerves (useful recovery in 100, 98.3, and 87.5% of repairs, respectively), than for the tibial, median and ulnar nerves (useful recovery in 63.9, 52, and 43.6% of repairs, respectively; P < 0.05). In addition, motor recovery potential was significantly the worst with peroneal nerve repairs (useful recovery in 15.2% of patients; P < 0.05). After low-level repairs, motor recovery potential was similar for all nerves (useful recovery in the range of 88.9–100% of patients and in 56.3% of peroneal nerve repairs).

CONCLUSION:

Sensory recovery potential is similar for the median, ulnar, and tibial nerves. The expression of motor recovery potential depends on the repair level. With low- and high-level repairs, it does not stand out in an obvious way, but it is fully expressed with intermediate-level repairs, classifying nerves into three categories with excellent, moderate, and poor recovery potential.

Mononeuropathies of the radial nerve: clinical and neurographic findings in 91 consecutive cases

Retrospective features of 91 consecutive cases (68 men, 23 women; mean age 44.4 years) of radial mononeuropathy diagnosed over the last 8 years in two electromyography (EMG) services are reported to define the clinical and electrophysiological findings of radial neuropathies in relation to traumatic and non-traumatic causes and site of injury. The occurrence of radial neuropathy was 0.65 x 100 first electromyographic examinations. The most frequent site of damage was the main trunk at the spiral groove of the humerus (36%); the most frequent cause was nerve trauma (70%) due to fracture (36%). In neuropathies of the main trunk and posterior interosseous (PI) nerve, "complete nerve injury" was observed in 36% of cases, conduction motor block in 33% and motor conduction velocity slowing in 46%. At least one of these findings was present in 51%, whereas motor neurography was normal in 13% of cases. Sensory action potential (SAP) anomalies were observed in 51% of cases. In neuropathy of the superficial radial nerve, no SAP was detected in 30% of cases; in all others except one, SAP was reduced in amplitude. Non-traumatic neuropathies showed severer conduction block and less severe anomalies of SAP than traumatic neuropathies. No differences were found between men and women. EMG is essential for confirming the site of injury and neurographic study may be helpful for diagnosis, providing information about lesion type and severity.