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.

Utility of intraoperative neurophysiological monitoring in detecting motor and sensory nerve injuries in pediatric high-grade spondylolisthesis

BACKGROUND CONTEXT

Intraoperative neuromonitoring (IONM) during surgical correction of spinal deformity has been shown to reduce iatrogenic injury in pediatric and adult populations. Although motor-evoked potentials (MEP), somatosensory-evoked potentials (SSEP), and electromyography (EMG) have been shown to be highly sensitive and specific in detecting spinal cord and nerve root injuries, their utility in detecting motor and sensory nerve root injury in pediatric high-grade spondylolisthesis (HGS) remains unknown.

PURPOSE

We aim to assess the diagnostic accuracy and therapeutic impact of unimodal and multimodal IONM in the surgical management of HGS.

STUDY DESIGN/SETTING

Retrospective cohort study.

PATIENT SAMPLE

Pediatric patients undergoing posterior spinal fusion (PSF) for treatment of HGS.

OUTCOME MEASURES

Data on patient demographics, spinopelvic and spondylolisthesis parameters, and the presence of pre-and postoperative neurological deficits were collected.

METHODS

Intraoperative MEP, SSEP, and EMG alerts were recorded. Alert criteria were defined as a change in amplitude of more than 50% for MEP and/or SSEP, with or without change in latency, and more than 10 seconds of sustained EMG activity. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were calculated for each modality and the combination of MEP and SSEP. The 95% confidence intervals (CIs) were calculated using the exact (Clopper-Pearson) method.

RESULTS

Fifty-four pediatric patients with HGS undergoing PSF between 2003 and 2021 in a single tertiary center were included. Seventy-two percent (39/54) of patients were female; the average age of patients was 13.7±2.3 years. The sensitivity of MEP in detecting new postoperative neurologic deficit was 92.3% (95% CI [64.0-99.8]), SSEP 77.8% (95% CI [40.0-97.2]), EMG 69.2% (95% CI [38.6-90.9]), and combination MEP and SSEP 100% (95% CI [73.5-100]). The specificity of MEP was 80.0% (95% CI [64.4-91.0]), SSEP 95.1% (95% CI [83.5-99.4]), EMG 65.9% (95% CI [49.4-79.9]), and combination MEP and SSEP 82.9% (95% CI [67.9-92.9]). The accuracy of SSEP was 92.0% (95% CI [80.8%-97.8%]), and the combination of MEP and SSEP was 86.8% (95% CI [74.7%-94.5%]). Twelve (22.2%) patients had a new motor or sensory deficit diagnosed immediately postoperatively. Nine patients made a full recovery, and 3 had some neurologic deficit on final follow-up.

CONCLUSION

Unimodal IONM using SSEP and MEP alone were accurate in diagnosing sensory and motor nerve root injuries, respectively. The diagnostic accuracy in predicting motor and sensory nerve injuries in pediatric HGS improved further with the use of multimodal IONM (combining MEP and SEP). We recommend the utilization of multimodal IONM in all HGS PSF surgeries.

[Relevance of Early Structured Diagnosis to Successful Nerve Reconstruction: A Case Report of an Alpine Professional Skier with an Axillary Nerve Injury]

Among high-speed sports, an increased number of high-speed injuries have been observed in alpine downhill racing. We report the case of a young professional ski racer who sustained a shoulder dislocation with an avulsion of the axillary nerve during a World Cup race. After initial treatment was provided for the shoulder dislocation, the patient was left with abduction weakness and a sensory deficit in the region of the deltoid muscle. She underwent electrophysiological and clinical examinations and visited our centre with delay. We immediately performed surgical treatment with a nerve transfer and nerve transplantation. After only 11 months following her fall, she was able to resume her training program. This case report shows the importance of early diagnostic investigation, a visit to a centre of plastic surgery and the good outcome after surgical treatment in patients with peripheral nerve injuries.

A review of 100 iatrogenic nerve injuries: delays in referrals remain significant

INTRODUCTION

This is a retrospective study of 100 consecutive patients with iatrogenic nerve injuries, as seen in a tertiary referral centre over a six-year period.

MATERIALS AND METHODS

Patients who presented with new-onset nerve palsy involving a motor or mixed motor/sensory nerve following an operation were studied.

RESULTS

There were 44 male and 56 female patients with a mean age of 53 years (range 5-87 years). The median duration from the index procedures to referral was six months (range 0 days to 12 years). Approximately one third of referrals were made over 12 months since the index procedures. Twenty patients recovered spontaneously and were managed expectantly. Eighty patients underwent secondary interventions.

DISCUSSION

There remains a significant delay in referring postoperative nerve palsy to a nerve specialist. The majority of these cases will warrant secondary reconstructive surgery and delay in treatment may have a negative effect on the ultimate outcomes.

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.

Peripheral Nerve Injury Treatments and Advances: One Health Perspective

Peripheral nerve injuries (PNI) can have several etiologies, such as trauma and iatrogenic interventions, that can lead to the loss of structure and/or function impairment. These changes can cause partial or complete loss of motor and sensory functions, physical disability, and neuropathic pain, which in turn can affect the quality of life. This review aims to revisit the concepts associated with the PNI and the anatomy of the peripheral nerve is detailed to explain the different types of injury. Then, some of the available therapeutic strategies are explained, including surgical methods, pharmacological therapies, and the use of cell-based therapies alone or in combination with biomaterials in the form of tube guides. Nevertheless, even with the various available treatments, it is difficult to achieve a perfect outcome with complete functional recovery. This review aims to enhance the importance of new therapies, especially in severe lesions, to overcome limitations and achieve better outcomes. The urge for new approaches and the understanding of the different methods to evaluate nerve regeneration is fundamental from a One Health perspective. In vitro models followed by in vivo models are very important to be able to translate the achievements to human medicine.

State of the Art and Advances in Peripheral Nerve Surgery

This review is intended to describe and actualize the basic knowledge of the three basic entities that affect the peripheral nerve system and can be treated by surgery: nerve trauma, chronic nerve compressions, and tumors.Regarding trauma, emphasis is given on the timing of surgery, given the fact that the moment in which the surgery is performed and the employed microsurgical reconstruction technique are the most important factors in the final result. Open lesions with associated nerve injury should be managed with an early exploration carried out before 7 days. Closed injuries are usually deferred, with few exceptions, from 3 to 6 months after the trauma.In turn, chronic compressions require an appropriate clinical, neurophysiological, and imaging diagnosis. Isolated sensory symptoms can be treated actively though without surgery: motor signs like atrophy should be regarded as a sign for immediate surgery, as a deferred treatment might cause an irreversible nerve and muscular damage. Endoscopic approaches are a valuable tool for treatment in selected neuropathies.Finally, nerve tumors demand a thorough preoperative evaluation, as benign tumors are treated in a very different way when compared to malignant lesions. Benign tumors can usually be safely and completely resected without sacrificing the nerve of origin. When malignancy is confirmed, extensive resection to optimize patient survival is the main objective, potentially at the expense of neurological function. This may then be followed by adjuvant radiation and/or chemotherapy, depending on the nature of the tumor and the completeness of resection attained. The role of nerve biopsy remains controversial, and several modern diagnostic techniques might be helpful.

Incidence of peripheral nerve injury in revision total shoulder arthroplasty: an intraoperative nerve monitoring study

BACKGROUND

The incidence of nerve injuries in revision total shoulder arthroplasty (TSA) is not well defined in the literature and may be higher than that in primary procedures, with 1 study reporting a complication rate of 50% for shoulder revisions. Given that continuous intraoperative nerve monitoring (IONM) can be an effective tool in diagnosing evolving neurologic dysfunction and preventing postoperative injuries, the purpose of this study was to report on IONM data and nerve injury rates in a series of revision TSAs.

METHODS

A retrospective cohort review of consecutive patients who underwent revision TSA was performed from January 2016 to March 2020. Indications for revision included infection (n = 7); failed total arthroplasty and hemiarthroplasty secondary to pain, dysfunction, and/or loose components (n = 36); and periprosthetic fracture (n = 1). Of the shoulders, 32 underwent revision to a reverse TSA, 6 underwent revision to an anatomic TSA, and 6 underwent spacer placement. IONM data included transcranial electrical motor evoked potentials (MEPs), somatosensory evoked potentials, and free-run electromyography. The motor alert threshold was set at ≥80% signal attenuation in any peripheral nerve. Patients were screened for neurologic deficits immediately following surgery, prior to administration of an interscalene nerve block, and during the first 2 postoperative visits. Additional data collection included surgical indication, sex, laterality, age at surgery, procedure performed, body mass index, history of tobacco use, Charlson Comorbidity Index, medical history, and preoperative range of motion.

RESULTS

A total of 44 shoulders in 38 patients were included, with a mean age of 63.2 years (standard deviation, 13.0 years). Of the procedures, 22.4% (n = 10) had an MEP alert, with 8 isolated to a single nerve (7 axillary and 1 radial) and 1 isolated to the axillary and musculocutaneous nerves. Only 1 patient experienced a major brachial plexus alert involving axillary, musculocutaneous, radial, ulnar, and median nerve MEP alerts, as well as ulnar and median nerve somatosensory evoked potential alerts. Age, sex, body mass index, Charlson Comorbidity Index, and preoperative range of motion were not found to be significantly different between cases in which an MEP alert occurred and cases with no MEP alerts. In the postoperative period, no minor or major nerve injuries were found whereas distal peripheral neuropathy developed in 4 patients (9.1%).

CONCLUSION

Among 44 surgical procedures, no patients (0%) had a major or minor nerve injury postoperatively and 4 patients (9.1%) complained of distal peripheral neuropathy postoperatively. In this study, we have shown that through the use of IONM, the rate of minor and major nerve injuries can be minimized in revision shoulder arthroplasty.

Lumbosacral plexopathy due to pelvic hematoma after extracorporeal membrane oxygenation: A case report

RATIONALE

Peripheral nerve injury related to vascular complications associated with extracorporeal membrane oxygenation (ECMO) is perhaps underappreciated. Compared to the well-described central nervous system complications of ECMO, brachial plexopathy and lumbosacral plexopathy have rarely been reported. We report this case to heighten awareness of lumbosacral plexus injury due to pelvic hematoma formation after ECMO.

PATIENT CONCERNS

A 53-year-old woman developed a large pelvic hematoma with significant mass effect on intrapelvic structures after receiving lifesaving venoarterial ECMO for cardiogenic shock following a cardiac arrest. During her hospital course, she developed bilateral foot drop that was attributed to critical illness. Her lack of neurological recovery after 6 months prompted referral to neuromuscular medicine for consultation.

DIAGNOSIS

The patient was retrospectively diagnosed with bilateral lumbosacral plexopathy due to the large pelvic hematoma.

INTERVENTION

Electromyography/nerve conduction study (EMG/NCS) obtained at the time of referral to neuromuscular medicine localized her neurological deficits to the bilateral lumbosacral plexus and demonstrated no volitional motor unit action potentials in her lower leg muscles.

OUTCOMES

The patient had minimal recovery of strength at the level of the ankles but was ambulatory with solid ankle-foot orthoses due to spared proximal lower extremity strength. Unfortunately, the absence of any volitionally activated motor unit action potentials in her lower leg muscles on EMG performed 6 months after the initial injury was a poor prognostic indicator for successful reinnervation and future neurological recovery.

LESSONS

Neurological deficits occurring during the course of administration of ECMO require accurate localization. Neurology consultation and/or EMG/NCS may be useful if localization is not clear. Lesions localizing to the lumbosacral plexus should prompt radiographic evaluation with computed tomography of the abdomen and pelvis. Hemostasis of a retroperitoneal hematoma may be achieved with embolization. However, if neurological deficits do not improve, surgical consultation for hematoma evacuation may be warranted.

Peripheral Nerve Injuries in the Upper Extremity

Major peripheral nerve injuries are devastating and represent a very challenging clinical problem. Despite many years of advancement in peripheral nerve research, results so far have been fair at best, with only 50% of patients regaining useful function. Advancement of techniques in imaging, better understanding of the physiology of nerve recovery, improved repair and grafting options, and secondary reconstructive techniques, including tendon and nerve transfers, have helped facilitate a degree of more effective treatment. This article presents current concepts regarding the principles of management, expected outcomes, and new advancements in major upper extremity peripheral nerve injuries.

Musculoskeletal ultrasonography combined with electromyography in the diagnosis of massage-inducted lateral plantar nerve injury: A case report

INTRODUCTION

It is well known that foot massage is a very prevalent stress relief method in China. Literatures have reported various massage-inducted peripheral nerve injuries. However, massage-inducted lateral plantar nerve (LPN) injury is very rare. Here, we represent an unusual case of massage-inducted LPN damage, and we also report the diagnostic method of this patient using musculoskeletal ultrasonography combined with electromyography (EMG).

PATIENT CONCERNS

A 21-year-old woman presented symptoms of redness, swelling, pain and numbness in the medial right ankle joint for 2 days.

DIAGNOSIS

The results of musculoskeletal ultrasonography and EMG provide great help for doctors to make accurate diagnosis. The patient was eventually diagnosed with LPN injury.

INTERVENTIONS

No further foot massage was allowed. Vitamin B12 was taken orally for 2 months. Conservative therapy, including electrical stimulation therapy and infrared therapy, was conducted. Besides, active rehabilitation training was also performed.

OUTCOMES

The discomfort symptoms were relieved significantly after 2 months conservative treatment. Clinical symptoms and EMG examination illustrated satisfactory result during follow up time.

CONCLUSION

The report showed that the masseur should be very careful when doing foot massage to prevent nerve damage. Besides, musculoskeletal ultrasonography combined with EMG can provide important evidence for accurate and effective diagnosis of LPN injury.

Peripheral Nerve Injury in Thoracic Surgery Detected by Automated Somatosensory Evoked Potential Monitoring

Study Objective. Our objectives were to estimate the incidence of symptoms of peripheral nerve injury (sPNI) in thoracic surgical patients undergoing video-assisted thoracic surgery or open thoracotomy and to determine whether intraoperative somatosensory evoked potentials (SSEPs) waveform changes correlate with postoperative peripheral neuropathic symptoms. Methods. We conducted a prospective observational study in the operating room of a tertiary hospital. We measured SSEPs intraoperatively and assessed patients for sPNI postoperatively. Results. Forty-four patients consented. Six were excluded from analysis. We found that 42% (95% confidence interval [CI] = 26% to 57%) of patients undergoing thoracic surgery had significant changes in SSEP amplitude and latency. Furthermore, 16% (95% CI = 4% to 28%) of patients had new postoperative symptoms of sensory or motor deficits in an upper extremity. We calculated a sensitivity of 66.7% (95% CI = 29.0% to 100%) and a specificity of 50% (95% CI = 33% to 67.3%) for the identification of sPNI based on automated intraoperative SSEP changes. Conclusions. We identified the incidence of SSEP changes in thoracic surgery (42%) and the incidence of postoperative sPNI after thoracic surgery (16%). We identified a positive correlation between intraoperative SSEP changes and postoperative sPNI, which after multivariate analysis was not significant given the small sample size of the study. By the time sensory and/or motor changes are detected postoperatively, it may be too late to reverse the nerve damage. Future versions of the EPAD device could provide anesthesiologists a way to monitor for the development of sPNI, and make changes before a potential injury becomes permanent.

Comparison of peripheral nerve repair using ethyl-cyanoacrylate and conventional suture technique in a rat sciatic nerve injury model

OBJECTIVE

The aim of this study was to compare the outcomes of primary nerve repair using either ethyl-cyanoacrylate or conventional microsuture technique in a rat peripheral nerve injury model.

METHODS

In this study, a total of 30 Wistar Albino rats weighing between 220 and 275 g were used. The rats were randomly divided into three groups (10 in each), including one control (group 1) and two experimental groups (group 2, conventional microsuture repair; group 3, cyanoacrylate repair). In each group, the sciatic nerve was identified and transected. No further intervention was performed in group 1. The nerve was repaired using the epineural technique with a 10/0 atraumatic nylon in group 2 and synthetic cyanoacrylate adhesive in group 3. At the fifth postoperative week, needle electromyography (EMG) was performed to measure distal latency, combined muscle action potential (CMAP), and motor nerve conduction velocity (MNCV). Following the EMG recordings, animals were euthanized. Nerve samples were collected to evaluate vacuolar degeneration, fibrosis, and foreign body reaction histopathologically.

RESULTS

In the EMG analysis, mean distal latency was significantly shorter in group 1 (0.85±0.09 ms) than in groups 2 (1.17±0.25 ms) (p=0.0052) and 3 (1.14±0.14 ms) (p=0.0026) while no significant differences existed between groups 2 and 3 (p>0.9999). The mean CMAP was greater in group 1 (10.5±0.35 mV) than in groups 2 (2.86±1.28 mV) (p=0.011) and 3 (2.16±1.34 mV) (p=0.0002), but there was no significant difference between groups 2 and 3 (p>0.9999). The mean MNCV was 53.5±5.95, 39.62±7.31, and 39.84±4.73 mm/sec in groups 1, 2, and 3, respectively. There was a significant difference between groups 1 and 2 (p=0.0052) and between 1 and 3 (p=0.0026), but not between 2 and 3 (p>0.9999). In the histopathological evaluation, the mean vacuolar degeneration score was 0, 2.12, and 1.88 in groups 1, 2, and 3, respectively. No obvious difference was observed between groups 2 and 3 (p=0.743). The mean fibrosis score was 0, 1.62, and 1.77 in groups 1, 2, and 3, respectively. There was no significant difference between groups 2 and 3 (p=0.888). The mean foreign body reaction score was 0, 2.5, and 2.44 in groups 1, 2, and 3, respectively. No difference was present between groups 2 and 3 (p=0.743).

CONCLUSION

Primary nerve repair using the cyanoacrylate adhesive may provide similar electrophysiological and histopathological results as compared to the conventional microsuture repair.

Sexual dysfunction in men after high energy pelvic fractures: Narrative review of targeted literature

Pelvic fractures represents high energy trauma with associated other organ injuries including intra-abdominal injuries, haemorrhage and extremity injuries. Anatomical location of genitourinary structures makes them vulnerable to injury with pelvic fracture. Incidence of sexual dysfunction varies in literature with 5% incidence of dysfunction in patients without urethral injury and 42% with urethral injuries. Hence in pelvic fracture, erectile dysfunction may be due to neurogenic, vascular, corporal and psychogenic injury. In this narrative review of targeted English literature from all level of evidences, which is written and supervised by experienced specialized orthopaedic, trauma and urology surgeons who were among the pioneers of conducting pelvis fracture management workshops in the country, we aim to describe the mechanism that can lead to erectile dysfunction after pelvic fracture, assessment principles, decision-making and preoperative planning and indications of operative managements.

The arthroscopic all-inside ankle lateral collateral ligament repair is a safe and reproducible technique

PURPOSE

Neurovascular structures around the ankle are at risk of injury during arthroscopic all-inside lateral collateral ligament repair for the treatment of chronic ankle instability. This study aimed to evaluate the risk of damage to anatomical structures and reproducibility of the technique amongst surgeons with different levels of expertise in the arthroscopic all-inside ligament repair.

METHODS

Twelve fresh-frozen ankle specimens were used for the study. Two foot and ankle surgeons with different level of experience in the technique performed the procedure on 6 specimens each. The repair was performed following a standardized procedure as originally described. Then, an experienced anatomist dissected all the specimens to evaluate the outcome of the ligament repair, any injuries to anatomical structures and the distance between arthroscopic portals and the superficial peroneal nerve (SPN) and sural nerve.

RESULTS

Dissections revealed no injury to the nerves assessed. Mean distance from the anterolateral portal and the SPN was of 4.8 (range 0.0-10.4) mm. The mean distance from the accessory anterolateral portal to the SPN and sural nerve was of 14.2 (range 7.1-32.9) mm and 28.1 (range 2.8-39.6) mm, respectively. The difference between the 2 surgeons' groups was non-statistically significant for any measurement (mm). In all specimens both fascicles of the anterior talofibular ligament were reattached onto its original fibular footprint. The calcaneofibular ligament was not penetrated in any specimen.

CONCLUSIONS

The all-inside arthroscopic lateral collateral ligament repair is a safe and reproducible technique. The clinical relevance of this study is that this technique provides a safe and anatomic reattachment of the anterior talofibular ligament, with minimal risk of injury to surrounding anatomical structures regardless of the level of experience with the technique.

Peripheral nerve injuries, pain, and neuroplasticity

INTRODUCTION

Peripheral nerve injuries (PNIs) cause both structural and functional brain changes that may be associated with significant sensorimotor abnormalities and pain.

PURPOSE OF THE STUDY

The aim of this narrative review is to provide hand therapists an overview of PNI-induced neuroplasticity and to explain how the brain changes following PNI, repair, and during rehabilitation.

METHODS

Toward this goal, we review key aspects of neuroplasticity and neuroimaging and discuss sensory testing techniques used to study neuroplasticity in PNI patients.

RESULTS

We describe the specific brain changes that occur during the repair and recovery process of both traumatic (eg, transection) and nontraumatic (eg, compression) nerve injuries. We also explain how these changes contribute to common symptoms including hypoesthesia, hyperalgesia, cold sensitivity, and chronic neurogenic pain. In addition, we describe how maladaptive neuroplasticity as well as psychological and personality characteristics impacts treatment outcome.

DISCUSSION AND CONCLUSION

Greater understanding of the brain's contribution to symptoms in recovering PNI patients could help guide rehabilitation strategies and inform the development of novel techniques to counteract these maladaptive brain changes and ultimately improve outcomes.

Can sural nerve injury be avoided in the sinus tarsi approach for calcaneal fracture?: A cadaveric study

There is no consensus regarding the references to determine the exact location of the skin incision to minimize iatrogenic sural nerve injury in the sinus tarsi approach for calcaneal fracture.The purpose of this cadaveric study was to describe the anatomical course of the sural nerve in relation to easily identifiable landmarks during the sinus tarsi approach and to provide a more practical reference for surgeons to avoid sural nerve injury.Twenty-four foot and ankle specimens were dissected. The bony landmarks used in the following reference points were the tip of the lateral malleolus (point A), lateral border of the Achilles tendon on the collinear line with point A (point B), posteroinferior apex of the calcaneus (point C), inferior margin of the calcaneus on the plumb line through point A (point D), and tip of the fifth metatarsal base (point E). After careful dissection, the distances of the sural nerve to points A and B in the horizontal direction (lines D1 and D2), points A and C in the diagonal direction (lines D3 and D4), points A and D in the vertical direction (lines D5 and D6), and points A and E in the diagonal direction (lines D7 and D8) were measured.The median ratio of D1 to D1+D2, D3 to D3+D4, D5 to D5+D6, and D7 to D7+D8 were 0.37 (range, 0.26-0.50), 0.23 (range, 016-0.33), 0.35 (range, 0.25-0.45), and 0.32 (range, 0.20-0.45), respectively.The distance ratios from this study can be helpful to avoid sural nerve injury during the sinus tarsi approach for calcaneal fractures. Established standard incision may have to be modified to minimize sural nerve injury.

The Electric Shock Sign-An Indication of a Partial Digital Nerve Laceration: A Report of Three Cases

CASE

Digital nerves injuries following penetrating injuries, lacerations, and blunt force trauma are common. This case series reports 3 acute cases of partial digital nerve lacerations where patients presented with a similar electric shock-like sensation, the "electric shock sign" radiating distally along the digital nerve distribution. The lancinating pain commonly occurs with active or passive finger extension. All 3 patients underwent operative repair of the digital nerve lacerations. With follow-up ranging between 4.5 months and 11 years, there was complete resolution of their pain.

CONCLUSIONS

The electric shock clinical sign can be an indicator of a partial digital nerve laceration.

Electrophysiological and etiological evaluation of 119 cases of wrist drop: A single center study

OBJECTIVE

To explore the pattern of electrodiagnostic findings in cases of wrist drop and compare gender, involved side of the body, and military versus civilian population for the aetiology of wrist drop.

METHODS

This cross-sectional study was conducted at Armed Forces Institute of Rehabilitation Medicine Rawalpindi, Pakistan, from August 2013 to December 2014, and comprised wrist drop cases regardless of age or gender. Evaluation was done using XLTEK Neuromax 1004 EMG unit in line with the recommended protocol for electrodiagnostic evaluation of a suspected radial nerve injury(RNI). SPSS 20 was used for data analysis.

RESULTS

Of the 119 patients, 97(81.5%) were males, 66(55.5%) were in the 16-30 years' age group, and 96(80.7%) were military personnel. RNI at the mid-arm level was the commonest cause in 88(73.9%) cases. The frequent inciting event was trauma with fracture of the humerus in 39(32.8%) cases. Eighty-four (70.6%) lesions were axonal. Ninety-four (79%) individuals had no associated injury to other nerves. Injuries due to trauma were more frequent in males (p<0.001), on the right side (p=0.046), and in the military population (p=0.05).

CONCLUSIONS

RNI at the mid arm level was the commonest cause of wrist drop in our sample and fracture of the humerus was the main inciting event..

Identifying Complications and Optimizing Consultations following Transradial Arterial Access for Cardiac Procedures

BACKGROUND

The radial approach to cardiac procedures has become increasingly common. Although previous studies have suggested a favorable risk profile, serious complications can occur. The purpose of this study is to examine the incidence, subsequent treatment, and outcome of all suspected significant neurovascular complications following transradial cardiac procedures at a large US hospital.

METHODS

We reviewed all patients who underwent a left heart catheterization, coronary angiogram, or percutaneous coronary intervention via the transradial approach at a single large academic medical center in the United States between 2010 and 2016. Consultations to the vascular and hand surgery services were examined to assess demographic variables, risk factors, presenting symptoms, subsequent treatment, and outcome of all serious complications.

RESULTS

A total of 9,681 radial access cardiac procedures were performed during the study period. Twenty-four cases (0.25%) were suspected to have major complications and subsequently received consults. A total of 18 complications were diagnosed, including 8 vascular injuries or perforations, 4 hematomas, 4 radial artery occlusions, 1 case of compartment syndrome, and 1 severe radial artery spasm. Of the complications noted, 3 (16.7%) required operative interventions, but all recovered neurovascular function.

CONCLUSIONS

Radial artery access for cardiac procedures has become increasingly common and has been associated with a low rate of major peripheral neurovascular complications. The majority (83.3%) of complications were successfully treated with a nonoperative management algorithm.

Bilaterally prolonged latencies of pain-related evoked potentials in peripheral nerve injuries

OBJECTIVE

Cross-sectional study to test the applicability of pain-related evoked potentials (PREP) for the diagnosis of peripheral nerve injuries (PNI).

INTRODUCTION

Patients with generalized polyneuropathies show prolonged latencies and decreased amplitudes of PREP indicating an impairment of A-delta fibers. Although these fibers are frequently affected in PNI, it is unclear, if PREP-testing detects PNI comparable to Nerve Conduction Studies (NCS).

METHODS

23 patients with PNI of one upper limb underwent bilateral PREP-testing (using concentric surface electrodes) and NCS. 41 healthy controls underwent PREP-testing only. We determined pain thresholds, N1-latencies and N1P1-amplitudes of PREP and analyzed them for group and side-to-side differences. Small-fiber function was evaluated using thermal detection thresholds of Quantitative Sensory Testing (QST). N1-latencies above a cut-off calculated by ROC-analysis were defined as abnormal in order to compare detection rates of PREP and NCS.

RESULTS

Patients with PNI showed bilaterally prolonged N1-latencies (ipsilateral: 167.0 ± 40.7 ms vs. 141.2 ± 20.5 ms / contralateral: 160.0 ± 41.0 ms vs. 140.2 ± 23.9 ms) without a significant side-to-side difference. Pain thresholds were increased on the affected side only (4.6 ± 5.2 mA vs. 2.4 ± 1.4 mA (controls)). N1P1-amplitudes did not differ between patients and controls. 7 (32%) patients showed prolonged N1-latencies (>176 ms) of PREP. NCS were abnormal in 16 (73%) cases. 13 (59%) patients showed thermal hypoesthesia in QST.

CONCLUSION

Contrary to our expectations, we found bilaterally prolonged N1-latencies and normal N1P1-amplitudes in patients with PNI. Our findings support the hypothesis of a bilateral generation of PREP and indicate that PREP are not suitable for the diagnosis of PNI.

Characteristics of Phrenic Nerve Injury During Pulmonary Vein Isolation Using a 28-mm Second-Generation Cryoballoon and Short Freeze Strategy

BACKGROUND

The reported incidence of phrenic nerve injury (PNI) varies owing to different definitions, balloon generations, balloon size, freezing regimen, and protective maneuvers. We evaluated the incidence, predictors, and outcome of PNI during cryoballoon pulmonary vein isolation in a large population.

METHODS AND RESULTS

Five hundred fifty atrial fibrillation patients underwent pulmonary vein isolation using one 28-mm second-generation cryoballoon and single 3-minute freeze strategy under diaphragmatic compound motor action potential (CMAP) monitoring. A total of 34 (6.2%) patients experienced PNI during the right superior and inferior pulmonary vein ablation in 30 and 4 patients, respectively. Applications were interrupted using double-stop techniques after 136 [104-158] second applications, and a pulmonary vein isolation was already achieved in all but one case. The baseline CMAP amplitude and timing of deflation (CMAPdef) were 0.75±0.30 and 0.17±0.17 mV, respectively. Persistent atrial fibrillation, larger right superior pulmonary vein ostia, and deeper balloon positions were associated with higher incidences of PNI. The CMAPdef predicted a PNI recovery delay, and the best cutoff value for predicting PNI recovery by the next day was 0.20 mV (sensitivity 57.1%, specificity 100%). Among 6 patients undergoing second procedures 8.5 (6.7-15.0) months later, the right superior pulmonary vein was durable in 3 with >120 second applications. Despite active balloon deflation, no significant pulmonary vein stenosis was observed in 15 right superior pulmonary veins evaluated 6 (5-9) months later. No patients had symptoms, and the PNI recovered 1 day and 1 month postprocedure in 21 and 4 patients, respectively.

CONCLUSIONS

PNI resulting from cryoballoon ablation was reversible. The double-stop technique is safe, and immediate active deflation following a CMAP decrease appears to be essential for faster PNI recovery.

Dorsal scapular nerve injury after trigger point injection into the rhomboid major muscle: A case report

BACKGROUND AND OBJECTIVE

We report the case of a patient who presented with right dorsal scapular neuropathy after a trigger point injection into the right rhomboid major muscle. Through a nerve conduction study and electromyography, we demonstrated dorsal scapular nerve injury in this patient.

CASE REPORT

A 38-year-old man complained that his right shoulder functioned less optimally during push-up exercises after a trigger point injection 4 weeks prior. Physical examination revealed mildly reduced right shoulder retractor muscle strength compared with the left side. We performed a nerve conduction velocity test and electromyography 5 weeks after the injection. The compound muscle action potential of the right dorsal scapular nerve showed low amplitude (left vs. right side: 5.2 vs. 1.6 mV) and delayed latency (left vs. right side: 4.9 vs. 6.8 ms). Positive sharp wave (1+) and mildly reduced recruitment were seen on electromyography of the rhomboid major muscle. The findings of the nerve conduction velocity test and electromyography indicated partial right dorsal scapular neuropathy. The nerve injury seemed to have been caused by the needle inserted during trigger point injection.

CONCLUSION

Clinicians should pay attention to the occurrence of dorsal scapular nerve injury when performing trigger point injection into the rhomboid muscle.

The advantage of early plication in children diagnosed with diaphragm paresis

BACKGROUND

In this single-center study, we sought to determine the frequency of phrenic nerve injury leading to diaphragm paresis (DP) in children following open cardiac surgery over the last 10 years, and to identify possible variables that predict the need for plication and associated clinical outcomes.

METHODS

Patients diagnosed with DP were identified from departmental databases and a review of clinical diaphragm ultrasound images. A cohort was analyzed for predictors of diaphragm plication and associations with clinical outcomes. Cumulative proportion graphs modeled the association between plication and length of stay.

RESULTS

DP was diagnosed in 161 of 6448 patients (2.5%) seen between January 2002 and December 2012. All diagnoses but 1 were confirmed by ultrasound. Plication of the diaphragm was performed in 30 patients (19%); compared with patients who did not undergo plication, these patients were younger (median age, 10 days vs 138 days; P < .001), more likely to have undergone deep hypothermic circulatory arrest (47% vs 18%; P = .005), had a longer duration of positive pressure ventilation (median, 15 days vs 7 days; P < .001), and had longer lengths of stay in both the intensive care unit (median, 23 days vs 8 days; P < .0001) and the hospital (median, 37 days vs 15 days; P < .0001). Early plication was associated with reduction in all intervals of care.

CONCLUSIONS

Early plication should be considered for patients with diaphragm paresis requiring prolonged respiratory support after cardiac bypass surgery. Longer follow-up evaluation is required to better define the long-term implications of plication.

Interest of the "compress test" in diagnosis of nerve injury in hand wounds

INTRODUCTION

Hand wounds are a common cause of emergency department admission. Digital nerve lesions are found in 5% of palm wounds. Early diagnosis reduces the risk of morbidity, sequelae and litigation. Screening for digital nerve injury by the usual tests is difficult in an emergency context. We assessed the diagnostic value of the simple "compress test" to screen for pulp sensibility disorder and the factors that may influence the value of this examination, with a view to validating routine use.

MATERIAL AND METHOD

A retrospective study included 821 palm wounds treated between January 2014 and May 2016. There were 605 male and 216 patients; mean age, 42.8 years (range: 18-90 years). The dominant hand was involved in 307 cases (37.4%). Sensitivity, specificity, positive and negative predictive values, and positive and negative likelihood ratios of the compress test were calculated. Diagnostic value was also calculated according to age, gender, affected digit, dominant side and examiner's experience.

RESULTS

Clinical deficit was found in 412 cases (50.2%). A digital nerve lesion was found intraoperatively in 277 cases (33.6%). Test sensitivity was 87.3%, specificity 68.6%, positive predictive value 58.5%, negative predictive value 91.4%, positive likelihood ratio 2.78 and negative likelihood ratio 0.18. The test was more effective for thumb wounds and for examination by a junior surgeon. There were no differences according to injured side, innervation territory or gender.

CONCLUSION

This clinical test is reliable, with very good negative predictive value and good sensitivity, allowing its use in routine clinical practice. Nevertheless, surgical exploration of deep palm injuries should remain the rule.

[Postpartum nerve injury is usually not caused by neuroaxial anesthesia--a case report]

Postpartum nerve injury is usually not caused by neuroaxial anesthesia - a case report In this case report we describe a woman who after giving birth had numbness and could not support her weight on the right leg. Three attempts of epidural anesthesia had been made during labor. MRI imaging of the spinal cord showed no pathology. She was treated conservatively by a physiotherapist and recovered gradually. After six months all symptoms had resolved. Postpartum nerve injury is often thought to be due to neuroaxial anesthesia, although in most cases it is caused by labor itself. Postpartum nerve injuries has been reported to occur in up to 1% of newly delivered women and presents with numbness, weakness and/or pain in the lower extremities. It is caused by stretch or compression of nerves in the pelvic region, for example the lumbosacral plexus, either related to position while giving birth or by compression of nerves between the pelvic brim and the fetus head, which causes demyelination. The prognosis is good with spontaneous resolution of symptoms usually within 2-6 months.

Bridging the Gap in Peripheral Nerve Repair

Peripheral nerve injuries following trauma present an ongoing challenge to the hand surgeon. This review presents an overview of the topic with a historical perspective. Nerve anatomy and nerve injury classifications are discussed followed by a description of the biology of nerve regeneration. Methods used to bridge gaps in peripheral nerve repair are discussed in detail with a critical appraisal of the most recent literature. Recommendations for surgical treatment are formulated based on evidence-based medicine.

Imaging of radicals following injury or acute stress in peripheral nerves with activatable fluorescent probes

Peripheral nerve injury evokes a complex cascade of chemical reactions including generation of molecular radicals. Conversely, the reactions within nerve induced by stress are difficult to directly detect or measure to establish causality. Monitoring these reactions in vivo would enable deeper understanding of the nature of the injury and healing processes. Here, we utilized near-infrared fluorescence molecular probes delivered via intra-neural injection technique to enable live, in vivo imaging of tissue response associated with nerve injury and stress. These initially quenched fluorescent probes featured specific sensitivity to hydroxyl radicals and become fluorescent upon encountering reactive oxygen species (ROS). Intraneurally delivered probes demonstrated rapid activation in injured rat sciatic nerve but minimal activation in normal, uninjured nerve. In addition, these probes reported activation within sciatic nerves of living rats after a stress caused by a pinprick stimulus to the abdomen. This imaging approach was more sensitive to detecting changes within nerves due to the induced stress than other techniques to evaluate cellular and molecular changes. Specifically, neither histological analysis of the sciatic nerves, nor the expression of pain and stress associated genes in dorsal root ganglia could provide statistically significant differences between the control and stressed groups. Overall, the results demonstrate a novel imaging approach to measure ROS in addition to the impact of ROS within nerve in live animals.

Magnetic resonance neurography in the diagnosis of neuropathies of the lumbosacral plexus: a pictorial review

Magnetic resonance neurography (MRN) is an important tool to detect abnormalities of peripheral nerves. This pictorial review demonstrates the MRN features of a variety of neuropathies affecting the lumbosacral plexus (LSP) and lower extremity nerves, drawn from over 1200 MRNs from our institution and supplemented by the literature. Abnormalities can be due to spinal compression, extraspinal compression, malignancy, musculoskeletal disease, iatrogenesis, inflammation, infection, and idiopathic disorders. We discuss indications and limitations of MRN in diagnosing LSP neuropathies. As MRN becomes more widely used, physicians must become familiar with the differential diagnosis of abnormalities detectable with MRN of the LSP.

The Teenage Terrible Triad A Case Report

Anterior shoulder dislocation in the athlete may result in an assortment of injuries that often benefit from surgical stabilization procedures. These injury patterns can be complex, requiring a multimodal approach to treatment. We present a rare case of a traumatic anterior shoulder dislocation in a teenage athlete that resulted in humeral avulsion of the glenohumeral ligament, rotator cuff tear, and axillary nerve palsy. Surgical treatment enabled return to football within 1 year of injury, and full function was restored.

Epidemiology of Traumatic Peripheral Nerve Injuries Evaluated with Electrodiagnostic Studies in a Tertiary Care Hospital Clinic

OBJECTIVE

To describe the etiologies and frequency of traumatic peripheral nerve injury (TPNI) seen in the electrodiagnostic laboratory of a tertiary care hospital in Puerto Rico.

METHODS

The charts of patients who underwent an electrodiagnostic study for a TPNI were revised. The main outcome measure was the frequency of each injury by anatomic location, specific nerve or nerves affected, injury mechanism, and injury severity.

RESULTS

One hundred forty-six charts were included, and in them were listed a total of 163 nerve injuries; 109 (74.7%) cases were men and 37 (25.3%) were women. The mean age was 33.6 years. The facial nerve, the brachial plexus, and the ulnar nerve were more frequently injured than any other nerve or nerve bundle. The ulnar, sciatic, median, and radial nerves and the lumbosacral plexus were more commonly injured as a result of gunshot wounds than of any other mechanism of injury. The brachial plexus was most frequently injured in motor vehicle accidents and the facial nerve injuries most commonly had an iatrogenic cause. In terms of injury severity, 84.2% were incomplete and 15.8% were complete.

CONCLUSION

TPNIs are common in young individuals and potentially can lead to significant disability. Further studies are needed to assess the socioeconomic impact of these injuries on our population.

Publications on Peripheral Nerve Injuries during World War I: A Dramatic Increase in Knowledge

Publications from French (Jules Tinel and Chiriachitza Athanassio-Bénisty), English (James Purves-Stewart, Arthur Henry Evans and Hartley Sidney Carter), German (Otfrid Foerster and Hermann Oppenheim) and American (Charles Harrison Frazier and Byron Stookey) physicians from both sides of the front during World War I (WWI) contributed to a dramatic increase in knowledge about peripheral nerve injuries. Silas Weir Mitchell's original experience with respect to these injuries, and particularly causalgia, during the American Civil War was further expanded in Europe during WWI. Following the translation of one of his books, he was referred to mainly by French physicians. During WWI, several French books were in turn translated into English, which influenced American physicians, as was observed in the case of Byron Stookey. The establishment of neurological centres played an important role in the concentration of experience and knowledge. Several eponyms originated during this period (including the Hoffmann-Tinel sign and the Froment sign). Electrodiagnostic tools were increasingly used.

Evaluation of pediatric upper extremity peripheral nerve injuries

INTRODUCTION

The evaluation of motor and sensory function of the upper extremity after a peripheral nerve injury is critical to diagnose the location and extent of nerve injury as well as document functional recovery in children.

PURPOSE

The purpose of this paper is to describe an approach to the evaluation of the pediatric upper extremity peripheral nerve injuries through a critical review of currently used tests of sensory and motor function.

METHODS

Outcome studies on pediatric upper extremity peripheral nerve injuries in the Medline database were reviewed.

RESULTS

The evaluation of the outcome in children less than 10 years of age with an upper extremity peripheral nerve injury includes careful observation of preferred prehension patterns, examination of muscle atrophy and sudomotor function, provocative tests, manual muscle testing and tests of sensory threshold and tactile gnosis.

CONCLUSION

The evaluation of outcome in children with upper extremity peripheral nerve injuries warrants a unique approach.

Entrapment and traumatic neuropathies of the elbow and hand: An imaging approach

Ultrasound and magnetic resonance imaging currently offer a detailed analysis of the peripheral nerves. Compressive and traumatic nerve injuries are the two main indications for imaging investigation of nerves with several publications describing the indications, technique and diagnostic capabilities of imaging signs. Investigation of entrapment neuropathies has three main goals, which are to confirm neuronal distress, search for the cause of nerve compression and exclude a differential diagnosis on the entire nerve. For traumatic nerve injuries, imaging, predominantly ultrasound, occasionally provides essential information for management including the type of nerve lesion, its exact site and local extension.

Pathophysiology and Etiology of Nerve Injury Following Peripheral Nerve Blockade

This review synthesizes anatomical, anesthetic, surgical, and patient factors that may contribute to neurologic complications associated with peripheral nerve blockade. Peripheral nerves have anatomical features unique to a given location that may influence risk of injury. Peripheral nerve blockade-related peripheral nerve injury (PNI) is most severe with intrafascicular injection. Surgery and its associated requirements such as positioning and tourniquet have specific risks. Patients with preexisting neuropathy may be at an increased risk of postoperative neurologic dysfunction. Distinguishing potential causes of PNI require clinical assessment and investigation; a definitive diagnosis, however, is not always possible. Fortunately, most postoperative neurologic dysfunction appears to resolve with time, and the incidence of serious long-term nerve injury directly attributable to peripheral nerve blockade is relatively uncommon. Nonetheless, despite the use of ultrasound guidance, the risk of block-related PNI remains unchanged.

WHAT'S NEW

Since the 2008 Practice Advisory, new information has been published, furthering our understanding of the microanatomy of peripheral nerves, mechanisms of peripheral nerve injection injury, toxicity of local anesthetics, the etiology of and monitoring methods, and technologies that may decrease the risk of nerve block-related peripheral nerve injury.

Epidemiology of Traumatic Peripheral Nerve Injuries Evaluated by Electrodiagnostic Studies in a Tertiary Care Hospital Clinic

OBJECTIVES

Describe the etiology and frequency of traumatic peripheral nerve injuries (TPNI) in the electrodiagnostic laboratory of a tertiary care hospital.

METHODS

The charts of patients who underwent an electrodiagnostic study for a TPNI were revised. The main outcome measure was the frequency of each injury by anatomic location, involved nerve, mechanism, and severity.

RESULTS

146 charts were included for a total of 163 injured nerves; 109 (74.7%) males and 37 (25.3%) females. The mean age was 33.6 years. The facial nerve and the brachial plexus followed by the ulnar nerve were more frequently involved. The ulnar, sciatic, median, radial nerve, and the lumbosacral plexus were more commonly injured by gunshot wounds, the brachial plexus by motor vehicle accidents, and the facial nerve by iatrogenic causes. The majority of the injuries were incomplete or partial (84.2% were incomplete and 15.8% complete injuries).

CONCLUSIONS

TPNIs can lead to significant disability, but further investigation is needed to better understand their socio-economic impact.

Who presents to our electroneurophysiology laboratory?

OBJECTIVE

To determine the distribution rate of Electroneuromyography diagnosis and correspondence between the preliminary diagnosis and final outcome.

METHODS

The retrospective study was conducted at the Department of Neurology, Harran University, Sanliurfa, Turkey, and comprised record of patients diagnosed with Electroneuromyography during a 24-month period from April 2011 to April 2013. SPSS 11.5 was used for data analysis.

RESULTS

Of the 4,230 cases reviewed, 1,946 (46%) showed normal Electroneuromyography findings despite pathological Electroneuromyography findings in 2,284(54%) cases. The most common diagnosis was carpal tunnel syndrome in 721(17%) patients, followed by polyneuropathy 312(7.4%), peripheral nerve injury 238(5.6%), brachial plexus lesion 180(4.3%), myopathy 114(2.7%), lumbar radiculopathy 108(2.6%), poliomyelitis 62(1.5%) and injection neuropathy 62(1.5%).

CONCLUSIONS

Off-label use of Electroneuromyography may be reduced by using electroneurophysiological laboratory rotation as well as adequate and comprehensive clinical evaluation of patients.

[THERAPEUTIC APPROACH TO HUMERAL BONE FRACTURES COMPLICATED BY PERIPHERAL NERVE TRAUMA]

On the basis of treatment results of 28 patients, the authors suggested that the clinical method of diagnostics allowed performance of topical diagnostics of injury using bedside test. It would help to choose a therapeutic approach in each clinical case.

[Blood vessel and nerve damage in total hip arthroplasty]

Blood vessel and nerve damage are uncommon complications in total hip arthroplasty (THA). With an incidence between 0.1 and 0.2 % in primary THA these complications are rare but can be serious with a high mortality risk. The individual risk is determined by multiple factors depending on the surgeon's skills, the number of previous surgeries and the approach itself. The anatomy of the defect is an essential risk factor. Some procedures, such as the use of screws for cup fixation are associated with a higher risk of vascular and neural damage. The acetabular quadrant system of the hip as described by Wasielewski et al. is a useful tool to visualize the neurovascular anatomy of the hip, to detect the safe zone and subsequently prevent complications. Sciatic nerve palsy after total hip replacement is the most common nerve damage followed by femoral nerve damage. Previous surgery, a posterior approach and excessive leg extension are the most common risk factors for nerve damage. In order to diagnose nerve palsy after orthopedic surgery an electromyogram can be of use to assess the extent and prognosis. This article focuses on vascular and neural complications after total hip arthroplasty and the options for diagnosis, treatment and prevention.

[1H-MRS study on the metabolites of first dorsal interossei]

OBJECTIVE

To estimate the application of prognosis evaluation of ulnar nerve injury by 1H-magnetic resonance spectroscopy (1H-MRS).

METHODS

The metabolites of first dorsal interossei (FDI) of two hands from 12 healthy volunteers and 1 volunteer with complete ulnar nerve injury were detected by 1H-MRS and the data were statistically analyzed.

RESULTS

For the FDI of healthy adults, the female peaks area of extra-myocellular lipids (EMCL) was higher than the male (P < 0.05); There was no significant difference in Cho, Cr and intra-myocellular lipids (IMCL) between male and female (P > 0.05); There was no significant difference in all the peaks area between the left and right hand (P > 0.05). The EMCL peak of the injury side was higher than that of the healthy side, and the area of FDI was reduced in the volunteer with ulnar nerve injury.

CONCLUSION

Noninvasive and quantitative detection of 1H-MRS may be valuable for prognosis evaluation of peripheral nerve injury.

Use of somatosensory evoked potentials to detect and prevent impending brachial plexus injury during surgical positioning for the treatment of supratentorial pathologies

Somatosensory evoked potentials (SSEPs) are widely utilized for the intraoperative detection and prevention of nerve conduction injuries. Their use in identifying position-related injuries to the brachial plexus in patients undergoing supine craniotomies for the treatment of supratentorial pathology is not well documented. This case series describes three instances of unilateral upper extremity SSEP changes in patients positioned for supine craniotomies. In all three cases SSEP responses improved after repositioning. None of the patients exhibited new neurological deficits post-operatively. This case series highlights the importance of vigilant monitoring in the period after final positioning and demonstrates the usefulness of SSEPs as a tool to aid in the early detection and prevention of impending position-related nerve injury.