T2 Contributions to the Brachial Plexus

Abstract Objective: Recent advancements in neurotization and nerve grafting procedures have led to an increasing need for knowledge of the detailed anatomy of communicating branches between peripheral nerves. Although the surgical anatomy of the axilla has been well described, little is known regarding the degree or frequency of potential contributions to or communications with the brachial plexus. The aim of our study, therefore, was to explore extrathoracic, as well as potential intrathoracic, contributions to the brachial plexus from T2. Methods: The anatomy of the ventral primary ramus of T2 and the second intercostal nerve, including its lateral cutaneous contribution as the intercostobrachial nerve, was examined in 75 adult human cadavers (150 axillae), with particular emphasis on the communications with the brachial plexus. Results: Extrathoracically, communications were observed to occur in 86% of specimens. These contributions arose variably from either the intercostobrachial nerve or one of its branches and communicated with the medial cord (35.6%), medial ante-brachial cutaneous nerve (25.5%), or posterior antebrachial cutaneous nerve (24%). Whereas the majority of specimens (68.2%) were observed to have only one extratho-racic communication, 31.7% of specimens exhibited two. Intrathoracically, communications were observed to occur in 17.3% of specimens. These communications always arose from the ventral primary ramus of T2. When combining and comparing data within individual specimens, it was observed that those axillae without an extratho-racic contribution from the intercostobrachial nerve always contained an intrathoracic communication. Conclusion: Based on our findings, we conclude that 100% of specimens contained a communication branch between T2 and the brachial plexus. Considering the possible implications of this data, with regards to sensory innervation of the arm and axilla, further studies in this area of research could prove extremely beneficial.

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SITE-SPECIFIC FASCIA TUNING PEGS AND PLACES OF PERILOUS PASSAGE MYOFASCIAL CONSIDERATIONS IN UPPER EXTREMITY ENTRAPMENT NEUROPATHIES: A CLINICAL ANATOMISTS VIEW

International Journal of Anatomy and Research ◽

10.16965/ijar.2020.237 ◽

2020 ◽

Vol 8 (4.2) ◽

pp. 7823-7828

Author(s):

John Sharkey ◽

Keyword(s):

Brachial Plexus ◽

Upper Extremity ◽

Morphological Changes ◽

Modern Society ◽

Protective Role ◽

Grocery Store ◽

Sensory Innervation ◽

Site Specific ◽

Entrapment Neuropathies ◽

Intercostobrachial Nerve

The objective of this study was to identify common anatomical locations of densified fascia associated with axillary, musculocutaneous, median, ulnar and radial nerve entrapment. Additionally, a proposal concerning a tensegrity based expansive decompressive protective role of muscles and ligaments as ‘site-specific fascia tuning pegs’ is offered for consideration. This observational report provides a means to stimulate research into the dynamics of force transfer via tensegral mechanotransductive pathways possibly decompressing neurovascular structures. Morphological changes to fascia profunda, septal tissues, epineurium, perineurium and endomysial tissue in continuity with neural structures were noted. Entrapment neuropathies involving the upper extremity are a growing and widespread phenomenon within modern society. Upper extremity neuropathies affect dentists, athletes (professional and recreational), pianists, grocery store employees, office workers, cab drivers and a host of other professional and non-professional individuals. Neurovascular insults can develop at multiple sites referred to by anatomists as the three P’s [i.e. Places of Perilous Passage]. The complexity of the inter-communicating nerve network, known as the brachial plexus, is well described as are the referred pain patterns of the contributing terminal branches. Sensory innervation to the upper extremity includes most of the axilla while excluding a specific region of the medial upper extremity and axilla which is supplied by the intercostobrachial nerve [i.e. T2]. This observational study identified specific anatomical locations where increased fascial densification lead to reduced gliding of the various facial laminae due to densified, fibrotic or adhered fascial tissues. A new hypothesis emerged concerning “site-specific fascia tuning pegs” described as biological instruments [i.e. muscle fibers and ligaments] that modify the length and width of the various specialist neural and vascular tubes [i.e. epineurium, tunica adventitia]. This author hopes that providing this information will assist in improving diagnosis, treatment and prognosis of upper extremity neurovascular insults that result in pain or unpleasant changes in sensation. KEY WORDS: Neuropathy, Fascia, Entrapment, Brachial Plexus, Tensegrity, Densification, Fibrotic, Site-Specific Fascia Tuning Pegs.

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Anatomic variations of the extrathoracic course of the intercostobrachial nerve and its clinical significance

Asian Journal of Medical Sciences ◽

10.3126/ajms.v9i5.20291 ◽

2018 ◽

Vol 9 (5) ◽

pp. 77-80 ◽

Cited By ~ 1

Author(s):

Soubhagya Ranjan Nayak ◽

Smita Singh Banerjee

Keyword(s):

Peripheral Nerves ◽

Clinical Importance ◽

Intercostal Nerve ◽

Lateral Branch ◽

Superficial Fascia ◽

Breast Cancers ◽

Medical Sciences ◽

Nerve Blocks ◽

Indian Origin ◽

Intercostobrachial Nerve

Background: The intercostobrachial nerve (ICBN) can present anatomic alterations in its course, but in general it originates as a lateral branch of the second intercostal nerve and penetrates the axilla, in the mid axillary line. Its communication with brachial plexus (BP) is of clinical importance. Neurotization and nerve grafting procedures have renewed interest in the communications of peripheral nerves, like that of between BP and ICBN. Aims and Objective: The current study was conducted with an aim to observe the variation in the origin of extra thoracic course of the ICBN and its connection with the components of BP.Materials and Methods: One hundred thirty hemi-thoraxes of 65 adult cadavers (35male & 30 female) of Indian origin were dissected. After removal of the skin and superficial fascia, the ICBN was identified from its origin. The point of emergence from the intercostal space and its communication with BP was noted and photographed.Results: Extrathoracically, ICBN originated from the 2nd intercostals space in 100% specimens. Additionally ICBN originated from the 1st intercostals space in 3.8% specimens, from 3rd intercostals space in 20.7% cases. The ICBN communicated more frequently with medial cutaneous nerve of the arm (MCN) in 63% cases and with other BP branches in 44.6% cases.Conclusion: In the present study we observed ICBN and BP are coherently linked anatomically. The anatomical knowledge of ICBN origin and its variable communication with BP branchesis significant in the event of surgical treatment of breast cancers, lymph node clearance, anaesthetic nerve blocks and traction injuries to the brachial plexus.Asian Journal of Medical Sciences Vol.9(5) 2018 77-80

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Management of desmoid-type fibromatosis involving peripheral nerves

Arquivos de Neuro-Psiquiatria ◽

10.1590/s0004-282x2012000700008 ◽

2012 ◽

Vol 70 (7) ◽

pp. 514-519 ◽

Cited By ~ 8

Author(s):

Mario G. Siqueira ◽

Paulo L. Tavares ◽

Roberto S. Martins ◽

Carlos O. Heise ◽

Luciano H.L. Foroni ◽

...

Keyword(s):

Brachial Plexus ◽

Median Nerve ◽

Surgical Procedures ◽

Peripheral Nerves ◽

Soft Tissues ◽

Radical Surgery ◽

Cutaneous Nerve ◽

High Rate ◽

Fibroblastic Proliferation

Desmoid-type fibromatosis is an uncommon and aggressive neoplasia, associated with a high rate of recurrence. It is characterized by an infiltrative but benign fibroblastic proliferation occurring within the deep soft tissues. There is no consensus about the treatment of those tumors. We present a surgical series of four cases, involving the brachial plexus (two cases), the median nerve and the medial brachial cutaneous nerve. Except for the last case, they were submitted to multiple surgical procedures and showed repeated recurrences. The diagnosis, the different ways of treatment and the prognosis of these tumoral lesions are discussed. Our results support the indication of radical surgery followed by radiotherapy as probably one of the best ways to treat those controversial lesions.

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Recovery of Hand Function Following Nerve Grafting and Transfer in Obstetric Brachial Plexus Lesions

Journal of Reconstructive Microsurgery ◽

10.1055/s-2006-949714 ◽

2006 ◽

Vol 22 (06) ◽

Author(s):

Willem Pondaag ◽

Martijn Malessy

Keyword(s):

Brachial Plexus ◽

Hand Function ◽

Nerve Grafting ◽

Obstetric Brachial Plexus

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Investigation Into the Optimal Number of Intercostal Nerve Transfers for Musculocutaneous Nerve Reinnervation: A Systematic Review

Hand ◽

10.1177/1558944717744280 ◽

2017 ◽

Vol 13 (6) ◽

pp. 621-626 ◽

Cited By ~ 2

Author(s):

Hyuma A. Leland ◽

Beina Azadgoli ◽

Daniel J. Gould ◽

Mitchel Seruya

Keyword(s):

Systematic Review ◽

Brachial Plexus ◽

Donor Site ◽

Elbow Flexion ◽

Donor Site Morbidity ◽

Intercostal Nerve ◽

Optimal Number ◽

Musculocutaneous Nerve ◽

Nerve Transfers ◽

Meta Analyses

Background: The purpose of this study was to systematically review outcomes following intercostal nerve (ICN) transfer for restoration of elbow flexion, with a focus on identifying the optimal number of nerve transfers. Methods: A systematic review was performed following Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines to identify studies describing ICN transfers to the musculocutaneous nerve (MCN) for traumatic brachial plexus injuries in patients 16 years or older. Demographics were recorded, including age, time to operation, and level of brachial plexus injury. Muscle strength was scored based upon the British Medical Research Council scale. Results: Twelve studies met inclusion criteria for a total of 196 patients. Either 2 (n = 113), 3 (n = 69), or 4 (n = 11) ICNs were transferred to the MCN in each patient. The groups were similar with regard to patient demographics. Elbow flexion ≥M3 was achieved in 71.3% (95% confidence interval [CI], 61.1%-79.7%) of patients with 2 ICNs, 67.7% (95% CI, 55.3%-78.0%) of patients with 3 ICNs, and 77.0% (95% CI, 44.9%-93.2%) of patients with 4 ICNs ( P = .79). Elbow flexion ≥M4 was achieved in 51.1% (95% CI, 37.4%-64.6%) of patients with 2 ICNs, 42.1% (95% CI, 29.5%-55.9%) of patients with 3 ICNs, and 48.4% (95% CI, 19.2%-78.8%) of patients with 4 ICNs ( P = .66). Conclusions: Previous reports have described 2.5 times increased morbidity with each additional ICN harvest. Based on the equivalent strength of elbow flexion irrespective of the number of nerves transferred, 2 ICNs are recommended to the MCN to avoid further donor-site morbidity.

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Trends in Brachial Plexus Surgery: Characterizing Contemporary Practices for Exploration of Supraclavicular Plexus

Hand ◽

10.1177/15589447211014613 ◽

2021 ◽

pp. 155894472110146

Author(s):

J. Ryan Hill ◽

Steven T. Lanier ◽

Liz Rolf ◽

Aimee S. James ◽

David M. Brogan ◽

...

Keyword(s):

Brachial Plexus ◽

Treatment Strategies ◽

Technical Difficulty ◽

Nerve Grafting ◽

Structured Interviews ◽

Lower Trunk ◽

Nerve Transfers ◽

Case Vignettes ◽

Distal Nerve

Background There is variability in treatment strategies for patients with brachial plexus injury (BPI). We used qualitative research methods to better understand surgeons’ rationale for treatment approaches. We hypothesized that distal nerve transfers would be preferred over exploration and nerve grafting of the brachial plexus. Methods We conducted semi-structured interviews with BPI surgeons to discuss 3 case vignettes: pan-plexus injury, upper trunk injury, and lower trunk injury. The interview guide included questions regarding overall treatment strategy, indications and utility of brachial plexus exploration, and the role of nerve grafting and/or nerve transfers. Interview transcripts were coded by 2 researchers. We performed inductive thematic analysis to collate these codes into themes, focusing on the role of brachial plexus exploration in the treatment of BPI. Results Most surgeons routinely explore the supraclavicular brachial plexus in situations of pan-plexus and upper trunk injuries. Reasons to explore included the importance of obtaining a definitive root level diagnosis, perceived availability of donor nerve roots, timing of anticipated recovery, plans for distal reconstruction, and the potential for neurolysis. Very few explore lower trunk injuries, citing concern with technical difficulty and unfavorable risk-benefit profile. Conclusions Our analysis suggests that supraclavicular exploration remains a foundational component of surgical management of BPI, despite increasing utilization of distal nerve transfers. Availability of abundant donor axons and establishing an accurate diagnosis were cited as primary reasons in support of exploration. This analysis of surgeon interviews characterizes contemporary practices regarding the role of brachial plexus exploration in the treatment of BPI.

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Compression neuropathies of the forearm: anatomy, clinical features and management

British Journal of Hospital Medicine ◽

10.12968/hmed.2021.0187 ◽

2021 ◽

pp. 1-10

Author(s):

Alexander Scarborough ◽

Robert J MacFarlane ◽

Michail Klontzas ◽

Rui Zhou ◽

Mohammad Waseem

Keyword(s):

Peripheral Nerve ◽

Brachial Plexus ◽

Upper Limb ◽

Peripheral Nerves ◽

Clinical Presentation ◽

Permanent Damage ◽

Peripheral Nerve Lesions ◽

Clinical Presentations ◽

Wide Range ◽

Prompt Diagnosis

The upper limb consists of four major parts: a girdle formed by the clavicle and scapula, the arm, the forearm and the hand. Peripheral nerve lesions of the upper limb are divided into lesions of the brachial plexus or the nerves arising from it. Lesions of the nerves arising from the brachial plexus are further divided into upper (proximal) or lower (distal) lesions based on their location. Peripheral nerves in the forearm can be compressed in various locations and by a wide range of pathologies. A thorough understanding of the anatomy and clinical presentations of these compression neuropathies can lead to prompt diagnosis and management, preventing possible permanent damage. This article discusses the aetiology, anatomy, clinical presentation and surgical management of compressive neuropathies of the upper limb.

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Prolonged brachial plexus neuropathy: a rare complication following protracted endometriosis surgery in Lloyd-Davies position

BMJ Case Reports ◽

10.1136/bcr-2021-243408 ◽

2021 ◽

Vol 14 (11) ◽

pp. e243408

Author(s):

Anna Katrina Hay ◽

Anna McDougall ◽

Peter Hinstridge ◽

Sanjeev Rajakuldendran ◽

Wai Yoong

Keyword(s):

Brachial Plexus ◽

Brachial Plexus Injury ◽

Rare Complication ◽

Patient Positioning ◽

Sensory Innervation ◽

Plexus Brachialis ◽

Clinical Anatomy ◽

Reduction Strategies ◽

Risk Reduction Strategies ◽

Endometriosis Surgery

Brachial plexus injury is a rare but potentially serious complication of laparoscopic surgery. Loss of motor and/or sensory innervation can have a significant impact on the patient’s quality of life following otherwise successful surgery. A 38-year-old underwent elective laparoscopic management of severe endometriosis during which she was placed in steep head-down tilt Lloyd-Davies position for a prolonged period. On awakening from anaesthesia, the patient had no sensation or movement of her dominant right arm. A total plexus brachialis injury was suspected. As advised by a neurologist, an MRI brachial plexus, nerve conduction study and electromyography were requested. She was managed conservatively and made a gradual recovery with a degree of residual musculocutaneous nerve neuropathy. The incidence of brachial plexus injury following laparoscopy is unknown but the brachial plexus is particularly susceptible to injury as a result of patient positioning and prolonged operative time. Patient positioning in relation to applied clinical anatomy is explored and risk reduction strategies described.

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