Brachial Plexus Research Articles

A comparative study of 0.5% ropivacaine versus 0.5% ropivacaine with dexamethasone on postoperative pain in interscalene brachial plexus block for shoulder surgery

A comparative study of 0.5% ropivacaine versus 0.5% ropivacaine with dexamethasone on postoperative pain in interscalene brachial plexus block for shoulder surgery

Comparison of different acceleration factors of artificial intelligence-compressed sensing for brachial plexus MRI imaging: scanning time and image quality

Comparison of different acceleration factors of artificial intelligence-compressed sensing for brachial plexus MRI imaging: scanning time and image quality

Common sports‐related nerve injuries seen by the electrodiagnostic medical consultant

AbstractThe high physiologic demands of sports create dynamic stress on joints, soft tissues, and nerves which may lead to injuries in the athlete. Electrodiagnostic (EDx) assessment is essential to identify the correct diagnosis, localization, and prognosis, to guide management of sports‐related neuropathies. A comprehensive review was performed to provide the EDx medical consultant with a practical approach to the common peripheral nerve disorders seen in athletes. Sports‐related neuropathies reviewed include transient traumatic irritation of the brachial plexus and/or cervical nerve roots (“Burners and stingers,”) suprascapular and axillary neuropathies, ulnar neuropathy at the elbow (UNE) in throwers, ulnar neuropathy at the hand/wrist in cyclists, multi‐ligamentous knee injury, and foot/ankle neuropathies including tarsal tunnel syndrome. A thorough understanding of peripheral anatomy, possible entrapment sites, mechanisms of injury, and key physical examination findings is essential for correct diagnosis. EDx assessments beyond routine studies are generally required for sports‐related neuropathy, which may not necessarily follow typical entrapment patterns. Adjunct diagnostic imaging, such as point‐of‐care ultrasound and magnetic resonance imaging, are helpful tools to identify associated musculoskeletal pathology such as compressive cysts or nerve entrapment, which may be amenable to interventional or surgical treatment. When no clear reversible structural pathology exists, management of sports‐related neuropathy is athlete‐specific and generally multi‐modal, involving a combination of physical rehabilitation techniques to address muscle imbalances, load management, protective equipment, and interventional pain procedures.

KDM4A facilitates neuropathic pain and microglial M1 polarization by regulating BDNF in a rat model of brachial plexus avulsion

BackgroundMany patients with brachial plexus avulsion (BPA) suffer from neuropathic pain, but the mechanism remains elusive. Modifications of histones, the proteins responsible for organizing DNA, may play an important role...

Obstetric Brachial Plexus Palsy and Functional Implications: Which Joint in the Upper Extremity Is More Closely Associated?

Background and Objectives: The objective of this study is to examine the correlation between the active range of motion (ROM) of the affected upper extremity and functional capacity in children with Obstetric Brachial Plexus Palsy (OBPP) who have undergone the modified Hoffer tendon transfer technique. Materials and Methods: The study cohort comprised 52 children with OBPP, aged 4–14 years, who had undergone a shoulder tendon transfer. The ROM was quantified using a goniometer, while functionality was evaluated through the administration of the Brachial Plexus Outcome Measure (BPOM). Results: The study identified significant correlations between the shoulder ROM and the Brachial Plexus Outcome Measure (BPOM). Specifically, shoulder flexion (p = 0.017; r = 0.351) was positively associated with shoulder functionality, while shoulder internal rotation (p = 0.001; r = 0.481) was linked to appearance scores. A significant negative relationship was observed between elbow extension (p < 0.001; r = −0.512) and elbow and forearm activities. Conclusions: The study highlights the necessity of assessing both joint range of motion and body perception for effective treatment and follow-up, to improve the functionality and quality of life for children with OBPP.

Misexpression of Median Nerve Variation in Relation to 3rd Part of Axillary Artery – A Case Report

During a routine dissection of an adult male cadaver at the College of Medical Sciences in Bharatpur, Nepal, it was noted that the right median nerve was formed by three roots. This observation was made after a careful dissection of both upper limbs, including the axilla, arm, forearm, and palm. Of the three roots contributing to this anomalous median nerve, one originated from the lateral cord and two from the medial cord of the brachial plexus. Despite this atypical configuration, the distribution of the median nerve in the arm, forearm, and palm appeared normal, and the arterial pattern, including the axillary and brachial arteries, was also typical.

Anatomical study of brachial plexuses of a koala, a Tasmanian devil, and a common ringtail possum

Anatomical study of brachial plexuses of a koala, a Tasmanian devil, and a common ringtail possum

Ultrasound assessment of the frequency and variation of arteries in the interscalene region.

Given the abundance of arteries in the neck, a significant risk of puncturing arteries exists when performing a brachial plexus block. Therefore, it is important to confirm the presence of arteries when performing a brachial plexus block via the interscalene approach. This study aimed to investigate the frequency and variations of arteries in the interscalene region in healthy Japanese adults using ultrasonography. This is an observational study at a university hospital. We analyzed videos of the brachial plexus recorded in another study using an ultrasound device and then investigated the frequency of the presence of arteries and the location of arteries in the interscalene region. Among 68 cases, 48 (70.6%) had one or more arteries in the interscalene region (63 arteries in total). The artery frequency on the ventral side of the 5th cervical nerve (C5), between C5 and the 6th cervical nerve (C6), between C6 and the 7th cervical nerve (C7), between C7 and the 8th cervical nerve (C8), and on the dorsal side of C8 was 19.1%, 1.5%, 35.3%, 29.4%, and 7.4%, respectively. The artery frequencies between C6 and C7 and between C7 and C8 were higher than those between C5 and C6 and on the dorsal side of C8. Interscalene observations using ultrasound devices revealed a high artery frequency, with numerous topographic variations.

Bilateral First Rib Fractures in Blunt Trauma Patients: A Retrospective Study

Abstract Introduction: Unilateral fracture of the first rib frequently led to severe complications such as brachial plexus or major vascular injury. Bilateral first rib fracture (BFRF) is very rare. We aimed to study the incidence, mechanism of injury, management, and outcome of BFRF in blunt trauma patients in a community-based hospital. Methods: Data of all blunt trauma patients who were admitted to our institution with (BFRF from December 2014 through January 2017) were retrospectively collected. Data included demography, mechanism of injury, severity of the injury, associated injuries, management, and outcome. Results: During the study period, 4779 patients with blunt trauma were included in the trauma registry and 12 (0.25%) patients had BFRF. The mean age of standard deviation (SD) was 29 (8.3) years. Seven (58.3%) patients were involved in road traffic collisions and 5 (41.7%) patients fell from more than 3 m height. The most commonly associated thoracic injury was lung contusions in 8 (66.7%) patients. The median (range) Glasgow Coma Score on admission was 15 (14–15) and Injury Severity Score (SD) was 19 (10.5). Length of hospital stay mean (SD) was 6.8 (6.4) days. No patients died in the study. Conclusions: BFRF is a rare entity in blunt trauma patients caused by high-energy trauma. Major vascular or brachial plexus injuries in patients with BFRF are much less than those reported in the medical literature on unilateral first rib fractures. Associated injuries are the main cause of trauma-related morbidity rather than the direct effect of BFRF.

Post-procedural Brachial Neuritis: Clinical, Electrodiagnostic and Neuroimaging features.

Brachial neuritis is a monophasic condition affecting the brachial plexus and its branches, manifesting as acute shoulder and upper arm pain, followed by weakness and paresthesias. It can be triggered by antecedent events, including procedures such as surgery. Misdiagnosis and delay in diagnosis is common. Imaging is important to confirm the diagnosis of post-procedural brachial neuritis and exclude other etiologies. Clinical, electrodiagnostic, and neuroimaging features of patients with post-procedural brachial neuritis from a single quaternary care institution were identified and analyzed. Six (2 female) patients were identified with median age 62 (range 49-70) years. Antecedent procedures included 4 cervical spine surgeries, 1 rotator cuff repair, and 1 central venous catheter placement. Time to symptom onset ranged from 1-day to 2-weeks. The initial symptom for 5/6 patients was severe upper extremity pain followed by weakness. All patients had electrodiagnostic tests and MR neurography consistent with brachial neuritis. MR neurogram showed plexus and/or terminal branch abnormalities with associated muscular denervation edema. The C5 or C6 root, and/or upper trunk were always involved. The most common branches affected were the suprascapular, long thoracic, and axillary nerves. Hourglass constrictions of these nerves were seen in 3/6 patients. The average time to diagnosis was 3.4 (range 1.5-5) months. Post-procedural brachial neuritis is an underrecognized cause of acute upper extremity pain and weakness. MR neurography can exclude iatrogenic causes and document the presence of hourglass constrictions in affected nerves. Diagnostic neuroradiologists should be aware of this clinical entity and associated neuroimaging findings. HGC = hourglass constriction; EDX = electrodiagnostic; IRB = Institutional Review Board; ACDF = anterior cervical discectomy and fusion; NRS = Numerical Rating Scale; MUAP = motor unit action potential.

A Comparative Analysis of Magnesium Sulfate Administered Intravenously Versus Perineurally as an Additive to Ropivacaine in Supraclavicular Brachial Plexus Block Under Ultrasound Guidance: A Randomized Clinical Trial

A Comparative Analysis of Magnesium Sulfate Administered Intravenously Versus Perineurally as an Additive to Ropivacaine in Supraclavicular Brachial Plexus Block Under Ultrasound Guidance: A Randomized Clinical Trial

Early pain findings in infants with brachial plexus birth injury: Relationship with function and comorbidities, and cut-off point for fractures

BackgroundInfants with birth brachial plexus injury (BPBI) may have various comorbidities such as fractures, torticollis, plagiocephaly, central nervous system disorders. In infants with BPBI, it is important to identify fractures, which are common among comorbidities, objectively assess pain, and investigate factors that may be associated with pain. AimThe aim of this study is to determine the pain level, comorbidities, and motor function in infants with BPBI and to examine the relationship between these parameters. The second aim is to determine the cut-off value of the pain score that may be a sign of fracture in patients with BPBI, in order to suspect and predict a fracture in the shoulder region and to request additional examinations. Subjects and measurements59 infants with BPBI aged 15–90 days were included in the study. Comorbidities, active joint movements, and total upper extremity function assessed with the Active Movement Scale and pain scores measured with the FLACC Pain Scale were retrospectively analyzed. In addition, pain, comorbidities and motor function were investigated according to types of Narakas, which indicates the degree of nerve injury. ResultsOf the 59 participants, 18 (30.5 %) had at least one comorbidity and 12 (20.3 %) had fractures. The number of comorbidities (p = 0.41), the number of fractures (p = 0.84), and the level of pain (p = 0.71) did not differ by types of Narakas. There was a moderate negative correlation between pain level and upper extremity motor function in upper trunk injuries (p < 0.5, −0.67 < r < −0.46). There was a difference in pain level measured by palpation (p < 0.01) and passive joint movement (p < 0.01) in infants with and without comorbidities. To suspect a fracture in the shoulder region and to request further evaluation, the cut-off value of the Flacc pain level, which may predict a fracture, was 3.5 points for palpation and passive shoulder abduction and 4.5 points for passive external rotation. ConclusionThis is the first study in the BPBI to measure pain in infants using a quantifiable and widely used assessment. Pain level was ranked from high to low as infants with fractures, infants with comorbidities other than fractures and infants without comorbidities. Increased pain adversely affects motor function and pain above the cut-off values is a predictor of fracture.

Two-Stage Glenohumeral Fusion for the Paralytic Shoulder

BackgroundShoulder fusion after nerve injury can improve overall arm function, however high revision and low patient satisfaction rates have been described. The purpose of this study is to describe a two-stage shoulder fusion, first pinning in a position of function and then converting to a shoulder fusion. Our hypothesis is that temporary pinning improves overall satisfaction after shoulder fusion in comparison to satisfaction reported in the literature. MethodsA retrospective review was performed for patients receiving two-stage shoulder fusion between 2020 and 2023. Patient demographics and clinical outcomes were recorded. Univariate statistics were performed to compare pre- and postoperative values. ResultsEighteen patients with an average age of 47 +/- 17.3 years and average follow-up of 23.7 +/- 4.5 months were included. Preoperative diagnoses included brachial plexus injury (n=13; 72%), late presentation obstetric brachial plexus injury (n=2; 11%), traumatic brain injury (n=1; 14.2%), cervical spinal cord injury (n=1; 14.2%) and iatrogenic axillary nerve injury with advanced arthritis (n=1;14.2%). Twelve (67%) patients received unilateral shoulder fusion 2.7 +/- 1.9 days after their initial pinning. Six patients (28.6%) did not receive a second stage fusion. Reasons for not continuing with fusion were attributed to perceived hand function and arm position. Three patients received two shoulder pinnings prior to their fusion to adjust the fusion position to accommodate more internal rotation. After fusion, both SSV (5.2 +/- 5.5% versus 71.6 +/- 10.4%; p<0.001) and pain (2.3 ± 4.0 vs 0.5 ± 0.71; p=0.56) improved. Forward elevation (5 +/- 12 versus 108 +/-35; p=0.01), abduction (10 +/- 15 versus 78 +/-9; p<0.001)), and external rotation (5 +/- 12 versus 22 +/- 17; p=0.26) all improved postoperatively while internal rotation remained limited (1.3 +/- 0.9 versus 1.2 +/- 0.5; p=0.84). Time to union was 15.4 +/- 15.4 weeks confirmed with CT scan. There was one (5.5%) reoperation for non-union, and patient satisfaction was 92% (n=11/12). ConclusionShoulder fusion after neurologic injury provides improved function and patient outcomes, however some patients may be unsatisfied with their new arm position. Percutaneous pinning prior to fusion is tolerated and allows patients to trial potential fusion positions. This method may improve patient satisfaction and avoid excess morbidity in those that would not be satisfied with a shoulder fusion.

The Pericoracoid Tissue Release in Children With Brachial Plexus Birth Injury

The Pericoracoid Tissue Release in Children With Brachial Plexus Birth Injury

Feasibility of a simultaneous ultrasound (US) and peripheral nerve stimulation (PNS) guided interscalene brachial plexus injection in calves

Feasibility of a simultaneous ultrasound (US) and peripheral nerve stimulation (PNS) guided interscalene brachial plexus injection in calves

Comparative study between fentanyl and dexmedetomidine as adjuvant to ropivacaine in supraclavicular brachial plexus block: A prospective and randomized study

Comparative study between fentanyl and dexmedetomidine as adjuvant to ropivacaine in supraclavicular brachial plexus block: A prospective and randomized study

Myoelectric performance of the reconstructed elbow flexor in patients with brachial plexus injuries

Myoelectric performance of the reconstructed elbow flexor in patients with brachial plexus injuries

Reducing the Distance Between Anode and Cathode to Make Handheld Nerve Stimulators More Selective in Nerve Fascicle Selection: Report of Two Cases

ABSTRACTPrecise nerve fascicle identification is important in certain peripheral nerve procedures. Although we believe bipolar nerve stimulation with intraoperative neuromonitoring is a superior method, many rely on clinical response evoked by handheld monopolar nerve stimulators. We present a modification in the use of the latter for a more precise fascicle stimulation. A 55‐year‐old man with a right high brachial plexus injury and a 47‐year‐old woman with a left median nerve schwannoma were scheduled for exploration and ulnar‐to‐musculocutaneous nerve transfer, and for surgical excision respectively. Intraoperatively, we used a disposable handheld monopolar nerve stimulator in an unorthodox way, placing the anode right next to the cathode (both touching the same nerve fascicle). In the first case, a fascicle that showed flexor carpi ulnaris (FCU) and intrinsic hand muscle contraction with standard stimulation (anode placed on patient's skin), showed only FCU activation with our modified method, and was chosen as donor. A BMC grade M4 elbow flexion was achieved 9 months after surgery. In the second case, safe schwannoma excision was performed after our modified stimulation technique caused thenar muscle activation in a single, unaffected fascicle, while standard monopolar stimulation showed activation in several fascicles. No unexpected motor/sensory deficits were noted during follow‐up. This report shows an easy modification in the use of handheld nerve stimulators that improves selectiveness when looking for nerve fascicles.

Maternal body mass index, maneuvers, and neonatal morbidity associated with shoulder dystocia

BackgroundShoulder dystocia is associated with neonatal morbidity. Higher maternal prepregnancy body mass index is an established risk factor for shoulder dystocia, yet the relationship between maternal prepregnancy body mass index and resulting neonatal morbidity after shoulder dystocia is not well studied. ObjectivesWe assessed the association between body mass index and neonatal adverse outcomes following shoulder dystocia. The frequency and type of maneuvers used to resolve shoulder dystocia by maternal body mass index was compared. Study DesignWe conducted a retrospective cohort study of pregnant individuals who experienced a shoulder dystocia at delivery from June 2012-July 2021 at a tertiary care center. We included singleton non-anomalous livebirths ≥36 weeks’ gestation at a single academic medical center in the Midwestern US. The primary exposure was prepregnancy body mass index categorized as: <30 kg/m2 [referent], 30-34.9 kg/m2, and ≥35 kg/m2. The primary outcome was a composite neonatal morbidity including birth injury (brachial plexus injury or fracture), seizures, hypoxic ischemic encephalopathy, and 5-minute Apgar < 7. Secondary outcomes were neonatal intensive care unit admission and neonatal acidemia (cord arterial pH < 7.10). Shoulder dystocia duration and the number and types of maneuvers were compared by body mass index group. Multivariable logistic regression was used and adjusted for nulliparity, diabetes, operative vaginal delivery, and gestational age. ResultsAmong 872 individuals who experienced a shoulder dystocia at delivery, 602 (69.0%) had a body mass index <30 kg/m2, 160 (18.3%) had a body mass index between 30-34.9 kg/m2, and 110 (12.6%) had a body mass index ≥35 kg/m2. The median duration of shoulder dystocia was 40 seconds (interquartile range 30, 60 seconds) and did not vary by maternal body mass index. Deliveries complicated by body mass index ≥35 kg/m2 required a greater number of maneuvers compared to those with lower maternal body mass index (p<0.01). McRoberts (96.0%), suprapubic pressure (90.2%) and delivery of the posterior arm (41.1%) were the most frequent maneuvers in all body mass index groups. Rubin’s maneuver was more frequently used with body mass index ≥35 kg/m2 compared with body mass index <30 kg/m2 (34.6% versus 22.4%, p = 0.02, adjusted odds ratio 1.63, 95% CI 1.04-2.57). Composite neonatal morbidity did not differ by body mass index. Neonatal injury was more frequent with body mass index ≥35 kg/m2 compared with body mass index <30 kg/m2 (adjusted odds ratio 1.97, 95% CI 1.06-3.68). Interaction between body mass index and number of maneuvers was not statistically significant (p=0.94). ConclusionsAmong pregnant individuals who experienced a shoulder dystocia, increased prepregnancy body mass index was associated with an increased number of maneuvers performed during a shoulder dystocia, but not longer duration. Risk of neonatal injury following shoulder dystocia, but not the composite neonatal adverse outcome, was increased with body mass index ≥35 kg/m2.

Technique and Expected Benefit of Intraoperative Perfusion Imaging of Peripheral Nerves.

Peripheral nerve surgery, particularly in cases of nerve compression syndrome (NCS), necessitates a comprehensive evaluation of intraneural blood flow, as localized reductions in nerve perfusion are integral to the etiopathogenesis of such conditions. Although nerve perfusion is currently guided by morphologic characteristics, this assessment is subjective and prone to bias. Intraoperative fluorescence-assisted perfusion imaging with indocyanine green (ICG) is an established tool in flap and lymphatic surgery to objectively assess perfusion intraoperatively. However, only a few unspecific applications of ICG in peripheral nerve surgery have been published so far. In this study, we performed intraoperative perfusion imaging using ICG in 16 consecutive operations within the peripheral nervous system, including microsurgical reconstructions after obstetric brachial plexus injury, decompression for NCS, and vascularized ulnar nerve interposition transfers. Our findings show the utility of ICG in delineating healthy perfusion borders at proximal and distal stump levels after neuroma resection, and we demonstrate a correlation between histological findings and these clinically observed perfusion patterns. In NCS cases, we demonstrate that ICG imaging is effective in highlighting reduced perfusion predecompression and improved perfusion postdecompression. Additionally, ICG proved valuable for assessing perfusion of free vascularized nerve grafts. Intraoperative ICG perfusion imaging is a valuable tool during surgery of the peripheral nervous system, providing insights into the etiopathogenesis of NCS and aiding in the visualization of perfusion. This study underscores the potential of ICG in nerve surgery and its applicability for improving surgical outcomes and advancing our understanding of peripheral nerve pathologies.