Asociación de trasplante de progenitores hematopoyéticos y síndrome de Parsonage-Turner: ¿coincidencia o relación causa-efecto? / Association between hematopoietic stem cell transplantation and Parsonage Turner syndrome: coincidence or cause-effect relationship?

El síndrome de Parsonage-Turner o plexopatía braquial idiopática es una inflamación total o parcial del plexo braquial cuya presentación típica es una omalgia intensa y súbita, seguida de debilidad braquial y amiotrofia precoz. La etiología es desconocida, aunque se propone un mecanismo inmunomediado.El trasplante de progenitores hematopoyéticos es un tratamiento bien establecido de las neoplasias hematológicas y tiene un papel creciente en el tratamiento de enfermedades autoinmunes. Los efectos adversos neurológicos son probablemente infradiagnosticados.La asociación del síndrome de Parsonage-Turner y el trasplante de progenitores hematopoyéticos es muy poco conocida. Describimos dos casos clínicos de plexopatía braquial idiopática tras trasplante de células stem (progenitores) hematopoyéticas (TPH).La reconstitución del sistema inmune tras un trasplante de progenitores hematopoyéticos puede ser un desencadenante de plexopatía braquial, aunque se necesitan más estudios para entender la fisiopatología de esta entidad y establecer su relación causal con el trasplante. (AU)

Parsonage-Turner syndrome or idiopathic brachial neuritis is a total or partial inflammation of the brachial plexus, with a typical presentation as a sudden and very intense pain in the shoulder, followed by weakness and early amyotrophy. The etiology is still unknown, although an immune mediated mechanism is thought to be involved.Hematopoietic stem cell transplantation is a well-established treatment for hematological malignancies, but with a growing implication in the treatment of autoimmune diseases. The neurological side effects are probably underdiagnosed.The association of the Parsonage-Turner syndrome and the hematopoietic stem cell transplantation is scarce. We describe two clinical cases of idiopathic brachial plexopathy after hematopoietic stem cell transplantation.The reconstruction of the immune system after a transplant may be the trigger of a brachial plexopathy, but more studies are necessary for the etiology of this disease to be understood and to establish a cause-effect relation with the transplant. (AU)

Quality of life, functioning and participation of adult patients with an amputation following complex regional pain syndrome I or brachial plexus injury: a scoping review protocol.

INTRODUCTION: This planned scoping review aims to provide insight into current literature regarding perceived quality of life (QoL), functioning and participation of patients with upper limb amputations (ULA) because of therapy-resistant debilitating complex regional pain syndrome type I (CRPS-I) or brachial plexus injury (BPI). It is important to gain insight into these outcomes, so we can properly inform and select patients eligible for amputation. METHODS AND ANALYSIS: Joanna Briggs Institute methodology for scoping reviews, Systematic Reviews and Meta-Analyses Scoping Reviews guidelines and Arksey and O'Malley's framework will be used. Studies regarding adult patients with either BPI or CRPS-I who underwent ULA will be considered for inclusion. Studies should include one or more of the following topics: QoL, functioning or participation and should be written in English, German or Dutch. Searches will be conducted in the Cochrane database, PubMed, EMBASE and Google Scholar. Search strings will be provided by a licenced librarian. All relevant literatures will be considered for inclusion, regardless of published date, in order to give a full scope of available literature. Studies will be selected first by title, then abstract and finally by full article by two reviewers who will discuss after every round. A third reviewer will make final decisions to reach consensus if needed. Data will be presented as brief summaries and in tables using a modified data extraction table. ETHICS AND DISSEMINATION: No ethical approval is required since no original data will be collected. Results will be disseminated through publication in a peer-reviewed journal and presentations at (inter)national conferences.

Evaluation of Infantile Brachial Plexopathy Using 3T MRI and High-Resolution Ultrasound: Experience From a Tertiary Care Centre.

BACKGROUND: Currently, clinical assessment is the main tool for the evaluation of brachial plexus injury, complemented by electrophysiologic studies (EPS), and imaging studies whenever available. Imaging plays an important role as it enables the differentiation of pre-ganglionic and postganglionic injuries, and adds objectivity to presurgical evaluation. OBJECTIVES: The primary objective was to evaluate the utility of magnetic resonance imaging (MRI) and high-resolution ultrasonography (USG) in the localization and characterization of brachial plexus injury in infants. MATERIALS AND METHODS: In this prospective study, 34 infants with signs and symptoms of brachial plexus injury were evaluated by clinical examination, EPS, MRI, and USG. Imaging findings were correlated with intraoperative findings in infants who underwent surgical management. The association between EPS and MRI findings, and USG and MRI findings were assessed using Fisher's exact test. Semi-quantitative subjective analysis of various MRI sequences was done as well. RESULTS: The most common findings of preganglionic injury and postganglionic injury, in our study, were pseudomeningocele and nerve thickening, respectively. MRI detection of injuries had a significant association with EPS findings. All MRI-detected injuries had a muscle power of grade 3 or less. muscle. Three-dimensional (3D) short tau inversion recovery (STIR) sequence was found to be superior for detecting postganglionic injuries (P < 0.05). CONCLUSION: Imaging studies enable localization of the site of injury, determining the extent, and nature/morphology of injury. The gamut of findings obtained from MRI is far wider compared to that from USG. USG can be used as the first-line screening investigation.

Anatomical damages in the spinal nerve roots and the spinal cord after brachial plexus injury: descriptive study from a cohort of consecutive patients who underwent DREZ-lesioning for pain-practical implications.

BACKGROUND: Systematic descriptions of anatomical damage after brachial plexus injury (BPI) at the intradural level have been scarcely reported in detail. However, considering these damages, not only in the spinal nerve roots but also in the spinal cord itself, is crucial in determining the appropriate surgical approach to restore upper limb function and address refractory pain. Therefore, the authors present a descriptive study focusing on intradural findings observed during microsurgical DREZ-lesioning. METHODS: This study enrolled 19 consecutive patients under the same protocol. Microsurgical observation through exposure of C4 to Th1 medullary segments allowed to describe the lesions in spinal nerve roots, meninges, and spinal cord. Electrical stimulation of the ventral roots checked the muscle responses. RESULTS: Extensive damage was observed among the 114 explored roots (six roots per patient), with only 21 (18.4%) ventral (VR) and 17 (14.9%) dorsal (DR) roots retaining all rootlets intact. Damage distribution varied, with the most frequent impairments in C6 VRs (18 patients) and the least in Th1 VRs (14 patients), while in all the 19 patients for the C6 DRs (the most frequently impaired) and in 14 patients for Th1 DRs (the less impaired). C4 roots were found damaged in 12 patients. Total or partial avulsions affected 63.3% and 69.8% of DRs and VRs, respectively, while 15.8% and 14.0% of the 114 DRs and VRs were atrophic, maintaining muscle responses to stimulation in half of those VRs. Pseudomeningoceles were present in 11 patients but absent in 46% of avulsed roots. Adhesive arachnoiditis was noted in 12 patients, and dorsal horn parenchymal alterations in 10. CONCLUSIONS: Knowledge of intradural lesions post-BPI helps in guiding surgical indications for repair and functional neurosurgery for pain control.

An unusual relationship between the axillary artery and brachial plexus in a cross-breed dog cadaver: a proposal for revising the terminology for nerve loops.

In the left axilla of a formalin-embalmed adult female cross-breed dog, an unusual course of the axillary artery in relation to the brachial plexus was noted. A part of the axillary artery after the origin of the subscapular artery coursed through the loop formed by the contributions of the caudal pectoral and lateral thoracic nerves and then between the median and ulnar nerves. Thus, the common trunk for the latter two nerves was missing. Instead, in the proximal brachium, they communicated with each other in both directions. A communicating branch between the cranial and caudal pectoral nerves forming a nerve loop, ansa pectoralis lacked the axillary artery and was instead traversed by the subscapular artery. This is a variation in the relationship between the axillary artery and brachial plexus in the domestic dog and has not been reported in the literature yet. The axillary artery entrapped by the contributions of the caudal and lateral thoracic nerves may be considered as a risk factor for the neuroarterial compressions with non-specific signs and should be taken into account both in surgery and imaging.

Investigating the effect of anatomical variations in the response of the neonatal brachial plexus to applied force: Use of a two-dimensional finite element model.

The brachial plexus is a set of nerves that innervate the upper extremity and may become injured during the birthing process through an injury known as Neonatal Brachial Plexus Palsy. Studying the mechanisms of these injuries on infant cadavers is challenging due to the justifiable sensitivity surrounding testing. Thus, these specimens are generally unavailable to be used to investigate variations in brachial plexus injury mechanisms. Finite Element Models are an alternative way to investigate the response of the neonatal brachial plexus to loading. Finite Element Models allow a virtual representation of the neonatal brachial plexus to be developed and analyzed with dimensions and mechanical properties determined from experimental studies. Using ABAQUS software, a two-dimensional brachial plexus model was created to analyze how stresses and strains develop within the brachial plexus. The main objectives of this study were (1) to develop a model of the brachial plexus and validate it against previous literature, and (2) to analyze the effect of stress on the nerve roots based on variations in the angles between the nerve roots and the spinal cord. The predicted stress for C5 and C6 was calculated as 0.246 MPa and 0.250 MPa, respectively. C5 and C6 nerve roots experience the highest stress and the largest displacement in comparison to the lower nerve roots, which correlates with clinical patterns of injury. Even small (+/- 3 and 6 degrees) variations in nerve root angle significantly impacted the stress at the proximal nerve root. This model is the first step towards developing a complete three-dimensional model of the neonatal brachial plexus to provide the opportunity to more accurately assess the effect of the birth process on the stretch within the brachial plexus and the impact of biological variations in structure and properties on the risk of Neonatal Brachial Plexus Palsy.

Dorsal root entry zone lesioning for brachial plexus avulsion - technical evolution and long-term follow-up.

BACKGROUND: Brachial plexus avulsion (BPA) injuries can cause severe deafferentation pain. This has been successfully treated with dorsal root entry zone (DREZ) lesioning. Distortions in anatomy following a BPA injury can make identifying neural structures challenging. We describe a modification to the operative technique that improves the surgical view and the advanced intraoperative neuromonitoring (IONM) employed to identify DREZ. We have analysed the long-term outcomes for pain, quality of life, and complications in patients undergoing DREZ lesioning. METHODS: This is a single-centre retrospective case series including patients who underwent DREZ lesioning with IONM for brachial plexus avulsion between 2012 and 2022. Analysed data included pre- and postoperative pain (VAS), quality of life score for chronic pain, and complications. The evolution of the surgical approach is discussed. RESULTS: 44 consecutive patients underwent a DREZ lesioning procedure with intraoperative monitoring and mapping. In these patients the mean VAS score improved from 8.9 (7-10) to 1.87 (0-6) (p < 0.0001) at the time of discharge. 31 patients were followed-up for more than 12 months with a mean duration of follow-up of 41 months and their results were as follows: the mean VAS improved from 9.0 (7-10) to 4.1 (0-9) (p < 0.0001) at the last follow-up and the mean QOL values improved from 3.7 (2-6) to 7.4 (4-10) (p < 0.0001). The long-term outcomes were 'good' in 39%, 'fair' in 29% and 'poor' in 32% of patients. 55% of the patients were able to stop or reduce pain medications. CONCLUSIONS: Modifications of surgical technique provide better exposure of DREZ, and IONM aids in identifying DREZ in the presence of severe intra-dural changes. Long-term outcomes of DREZ lesioning indicate not only a reduction in pain but also a significant improvement in quality of life.

A Prefixed Four-Trunk Brachial Plexus with Anomalous Anatomy of All Subsequent Divisions, Cords, and Terminal Branches: A Cadaveric Case Report.

BACKGROUND The brachial plexus is a complex neural structure providing motor and sensory innervation to structures of the arm, shoulder, and upper chest. The anatomical structure is typically divided into roots, trunks, divisions, and cords. Due to the presence of multiple nerve roots and branches, anatomical variations are common. Awareness of variations from normal anatomy is important in imaging, administration of nerve blocks, and surgical procedures of the neck and shoulder region. CASE REPORT We present a case of multiple anatomic variations of the right brachial plexus identified in a cadaver during routine dissection. To summarize, we identified a prefixed plexus with anomalous contributions from the C4 nerve root. Nerve roots C4 and C5 emerged anterior to the anterior scalene muscle. Furthermore, 4 trunks, rather than the typical 3, gave rise to multiple anomalies in the branching pattern of the distal divisions and cords. To the best of our knowledge, this is the first such case reported in the published literature. CONCLUSIONS The current case report presents a combination of brachial plexus anomalies not previously described in the medical literature - specifically, a prefixed (C4-T1) brachial plexus positioned anterior to the anterior scalene muscle with anomalies of the trunks, divisions, cords, and terminal branches. The variations presented have implications in neurogenic compression, interscalene blocks, and trauma to the upper limb. Knowledge of these anomalies may better equip anatomists and clinicians to understand pathology and intervention of the upper limb.

Anatomical variations of the brachial plexus in adult cadavers: A descriptive study and clinical significance.

BACKGROUND: Brachial plexus injury is recognized as one of the most severe clinical challenges due to the complex anatomical configuration of the brachial plexus and its propensity for variation, which complicates safe clinical interventions. This study aimed to ascertain the prevalence and characterize the types of brachial plexus variations, and to elucidate their clinical implications. MATERIALS AND METHODS: We conducted meticulous dissections of 60 formalin-fixed cadavers' upper arm, axilla and lower neck to reveal and assess the roots, trunks, divisions, cords, and branches of the brachial plexus. The pattern of branching was noted by groups of dissecting medical students and confirmed by the senior anatomists. The variations discovered were record and photographed using a digital camera for further analysis. RESULTS: Variations in the brachial plexus were identified in 40 of the 60 cadavers, yielding a prevalence rate of 66.7%. These variations were classified into root anomalies (2.1%), trunk anomalies (8.5%), division anomalies (2.1%), and cord anomalies (4.3%). Notably, anomalies in communicating branches were observed in 39 cadavers (83.0%): 14 with bilateral anomalies, 14 with anomalies on the left side, and 11 on the right side. These communicating branches formed connections between the roots and other segments, including trunks, cords, and terminal nerves, and involved the median, musculocutaneous, and ulnar nerves. CONCLUSION: The frequency and diversity of brachial plexus variations, particularly in communicating branches, are significant in cadavers. It is imperative that these variations are carefully considered during the diagnostic process, treatment planning, and prior to procedures such as supraclavicular brachial plexus blocks and nerve transfers, to mitigate the risk of iatrogenic complications.

Neglected Sprengel's deformity in an 80-year-old female cadaver: a case report.

BACKGROUND: Sprengel's deformity is a congenital abnormality of the shoulder girdle. Because scapular retraction, such as the Green procedure, is usually performed during childhood to improve esthetics and shoulder function, Sprengel's deformity is rarely found in older patients. CASE PRESENTATION: We presented a unique case of a Japanese female cadaver with Sprengel's deformity at the age of 80 years. Anatomical dissection and radiological imaging revealed musculoskeletal anomalies associated with Sprengel's deformity, including Klippel-Feil syndrome, presence of an omovertebral bone, and absence of the trapezius muscle. In addition, bilateral cervical ribs were in contact with the brachial plexus. These anomalies may lead to numbness, pain, and limited range of motion of the neck and upper girdle with aging. CONCLUSIONS: Because most adult patients with Sprengel's deformity experience neck pain and limited movement of the shoulder, the presented case is a rare case of neglected Sprengel's deformity in an 80-year-old cadaver.

Optimizing donor fascicle selection in Oberlin's procedure: A retrospective review of anatomical variability using intraoperative neuromonitoring.

BACKGROUND: Transfer of the fascicle carrying the flexor carpi ulnaris (FCU) branch of the ulnar nerve (UN) to the biceps/brachialis muscle branch of the musculocutaneous nerve (Oberlin's procedure), is a mainstay technique for elbow flexion restoration in patients with upper brachial plexus injury. Despite its widespread use, there are few studies regarding the anatomic location of the donor fascicle for Oberlin's procedure. Our report aims to analyze the anatomical variability of this fascicle within the UN, while obtaining quantifiable, objective data with intraoperative neuromonitoring (IONM) for donor fascicle selection. METHODS: We performed a retrospective review of patients at our institution who underwent an Oberlin's procedure from September 2019 to July 2023. We used IONM for donor fascicle selection (greatest FCU muscle and least intrinsic hand muscle activation). We prospectively obtained demographic and electrophysiological data, as well as anatomical location of donor fascicles and post-surgical morbidities. Surgeon's perception of FCU/intrinsic muscle contraction was compared to objective muscle amplitude during IONM. RESULTS: Eight patients were included, with a mean age of 30.5 years and an injury-to-surgery interval of 4 months. Donor fascicle was located anterior in two cases, posterior in two, radial in two and ulnar in two patients. Correlation between surgeon's perception and IONM findings were consistent in six (75%) cases. No long term motor or sensory deficits were registered. CONCLUSIONS: Fascicle anatomy within the UN at the proximal arm is highly variable. The use of IONM can aid in optimizing donor fascicle selection for Oberlin's procedure.

Ultrasound accuracy for brachial plexus pathology.

AIM: To determine (a) the accuracy of ultrasound in detecting brachial plexus pathology and (b) outline the advantages and limitations of ultrasound compared to MRI for imaging the brachial plexus. MATERIAL AND METHODS: cases with clinically suspected brachial plexus pathology were evaluated first by ultrasound, followed by MRI. Patients with prior brachial plexus imaging were excluded. The final diagnosis was based on a combination of ultrasound, MRI, clinical follow-up, and surgical findings. The accuracy of the ultrasound was assessed by comparing the ultrasound and the final diagnoses. The mean clinical follow-up time following ultrasound was 1.8 ± 1.4 years. RESULTS: Ninety-two (64%) of the 143 cases had normal brachial plexus ultrasound and MRI examinations. Fifty-one (36%) of 143 cases had brachial plexus pathology on MRI, comprising post-radiation fibrosis (n=25, 49%), nerve sheath tumor (n=11, 21%), traumatic injury (n=7, 14%), inflammatory polyneuropathy (n=4, 8%), malignant infiltration (n=2, 4%), desmoid fibromatosis (n=1,2%), and neuralgic amyotrophy (n=1, 2%). Overall diagnostic accuracy of ultrasound for brachial plexus pathology was 98% (140/143), with three discordant cases (neuralgic amyotrophy n=1, inflammatory neuropathy n=1, postradiation fibrosis n=1) regarded as normal on ultrasound assessment. Sensitivity, specificity, and positive and negative predictive value of ultrasound for identifying brachial plexus pathology were 94%, 100%, 100%, and 97%, respectively. CONCLUSION: Ultrasound identifies brachial plexus pathology with high accuracy and specificity, showing comparable diagnostic efficacy to MRI. Ultrasound can serve as an effective first-line imaging investigation for suspected brachial plexus pathology.

Ultrasound guided costoclavicular block in pediatric population: A prospective observational study.

BACKGROUND: The costoclavicular space serves as an alternative approach to the infraclavicular brachial plexus block, and numerous studies in adults have demonstrated promising outcomes for distal upper limb surgery. Blocking the brachial plexus at this level is potentially advantageous because the cords are relatively superficial, located in close proximity to each other and easily identified using ultrasound. AIMS: This study aimed to assess the success rate and feasibility of costoclavicular block in children undergoing unilateral below elbow upper limb surgery. METHODS: Thirty children aged 2-12 years scheduled for unilateral below elbow surgery under general anesthesia were included. Costoclavicular block was performed under ultrasound and nerve stimulator guidance with 0.5% ropivacaine, 0.5 mL/kg. Success was evaluated based on the absence of significant hemodynamic response to skin incision made 20 min after the block. The sono-anatomy of costoclavicular space, ease of needling, complications, and the post-operative pain scores were assessed. RESULTS: The mean age and weight of the children were 6.5 ± 3.8 years and 19.7 ± 9.1 kg, respectively. The success rate of costoclavicular block in our cohort is 100%. Sonographic visualization was graded as excellent (Likert Scale 2) in 90% of cases. The plexus was located at a depth of 1.4 ± 0.3 cm from the skin, the lateral extent of cords from the artery was 0.8 ± 0.4 cm and they were observed inferior and lateral to the artery. The mean needling time was 3.6 ± 1.1 min. None of the children experienced complications such as vascular or pleural puncture, hematoma, Horner's syndrome or diaphragmatic palsy. Postoperative pain scores were low, and no rescue analgesia was required. CONCLUSIONS: In conclusion, the costoclavicular block exhibited a notably high success rate in pediatric population. This study substantiates that the three cords of the brachial plexus are consistently visible and superficial during ultrasound examination using this approach, confirming their separation from vascular structures and the reliable achievement of blockade without observed complications.

Neuromuscular choristoma-associated desmoid-type fibromatosis of the brachial plexus: Additional evidence to support a nerve-driven mechanism.

BACKGROUND: We have recently described circumferential nerve involvement of neuromuscular choristoma associated with desmoid-type fibromatosis (NMC-DTF) in cases involving the sciatic nerve, supporting a nerve-derived mechanism for the DTF. We wondered whether a similar growth pattern occurs in cases involving the brachial plexus (BP). METHODS: We reviewed all available magnetic resonance (MR) imaging in patients diagnosed at our institution with NMC or NMC-DTF of the BP. We also performed a literature search of patients with NMC or NMC-DTF of the BP. RESULTS: In our clinical records, four patients with NMC of the BP were identified, and three developed NMC-DTF. All three patients had MR imaging evidence of circumferential encasement of the BP. In the literature, we identified 15 cases of NMC of the BP, of which 12 had identified NMC-DTF. Four published cases included MR images, and only two were of sufficient quality for review. The single provided image in both cases demonstrated a similar pattern of circumferential encasement of the BP by the NMC-DTF. One additional case report was published without MR images but described circumferential involvement in the surgical findings. One unpublished case of NMC-DTF of the BP from an international radiology meeting also had this circumferential pattern pattern on MRI. CONCLUSIONS: The MRI findings of circumferential nerve involvement in patients with NMC-DTF of the BP are similar to our previously reported data in patients with NMC-DTF of the sciatic nerve, providing further imaging-based support of a nerve-driven mechanism. Clinical implications are presented based on the proposed pathogenetic mechanism.

Mechanisms and protective measures for radiation-induced brachial plexus nerve injury.

Radiation therapy is a common treatment modality for patients with malignant tumors of the head and neck, chest and axilla. However, radiotherapy inevitably causes damage to normal tissues at the irradiated site, among which damage to the brachial plexus nerve(BP) is a serious adverse effect in patients receiving radiation therapy in the scapular or axillary regions, with clinical manifestations including abnormal sensation, neuropathic pain, and dyskinesia, etc. These adverse effects seriously reduce the living quality of patients and pose obstacles to their prognosis. Therefore, it is important to elucidate the mechanism of radiation induced brachial plexus injury (RIBP) which remains unclear. Current studies have shown that the pathways of radiation-induced BP injury can be divided into two categories: direct injury and indirect injury, and the indirect injury is closely related to the inflammatory response, microvascular damage, cytokine production and other factors causing radiation-induced fibrosis. In this review, we summarize the underlying mechanisms of RIBP occurrence and possible effective methods to prevent and treat RIBP.

[Nerve Transfers in Children with Non-traumatic Amyoplasia] / Nerventransfers bei Kindern mit nicht traumatischer AmyoplasieNerve Transfers in Children with Non-traumatic Amyoplasia.

BACKGROUND: The treatment of obstetric brachial plexus palsy through primary reconstruction and nerve transfers has been established in the past decades. In the case of non-traumatic diseases that lead to flaccid paralysis and the inability to move the extremities, such as transverse myelitis (TM) or arthrogryposis multiplex congenita (AMC), which can have a wide variety of causes, the focus has been on rehabilitative therapy so far, while surgical interventions have been used to a lesser extent, e. g., in the form of osteotomies or muscle transfers. Our aim is to establish nerve transfers as a surgical option to improve mobility in non-traumatic amyoplasia. PATIENTS: This work presents the needs-adapted treatment of a total of 23 patients (aged 4 months to 64 months, 18 with AMC and 5 with TM) using nerve transfers on the upper extremity. RESULTS: We were able to show that early nerve transfers in the upper extremity enabled the reanimation of muscles in both AMC and TM. CONCLUSION: This work shows that the treatment of non-traumatic amyoplasia in children with selective nerve grafts is a successful method. Nerve transfers allow patients to gain or regain important functions for managing independent everyday life. The surgical methods have been established in the treatment of traumatic nerve injuries. They are well-known and can be carried out safely. We believe that this is an important treatment option for paediatric patients with paralysis associated with TM or AMC, which should also be known to the treating physicians.

Growth of the brachial nerve plexus with reference to topographical relation of the medianus nerve ansa with the thoracic wall and shoulder: a histologic study using human embryos and fetuses.

BACKGROUND: There is currently no information on positional changes in the brachial nerve plexus during prenatal growth. The subclavian-axillary artery passing through the medianus nerve ansa is considered a good landmark for evaluating the height of the plexus. MATERIALS AND METHODS: We used histologic sections from 9 embryos and 17 fetuses (approximately 6-15 weeks of gestational age) to identify the height of the ansa by referring to the level of the rib and the glenohumeral joint. RESULTS: The nerve ansa was usually (23 plexuses) observed at the level of the first and/or second ribs. However, it was sometimes observed above the first rib, at a distance equal to or more than an intercostal width (7 plexuses). In the latter group, the ansa was usually located below the glenohumeral joint. Thus, the joint was located higher than the first rib, although the upper extremities were in the anatomic position for all specimens. The left-right difference in the height of the plexus corresponded to or was less than the width of the first intercostal space. Despite the synchronized growth between the thorax and shoulder girdle, the brachial plexus showed a considerable variation in comparative height; the range corresponded to twice of an intercostal width. Whether the nerve plexus is located high or low is determined at an early developmental stage and is maintained during the later growth stages. CONCLUSION: The high-positioned plexus might cause nerve injury at delivery, followed by a glenohumeral joint deformity because of the fragility without fixation in the thorax.

Functional Free Muscle Transfer for Reconstruction of Traumatic Adult Brachial Plexus Injuries.

Traumatic brachial plexus injury is the most common indication for functional free muscle transfer, and elbow flexion recovery is the functional target, followed by shoulder stability and hand reanimation. In this article, we provide a literature review of functional free muscle transfer (FFMT) for adult traumatic brachial plexus injuries and the surgical technical recommendations to achieve the best functional results with FFMT for adult traumatic brachial plexus injuries.