Diseases of the Peripheral Nerve and Mononeuropathies
Philip B. Gorelick, Fernando D. Testai, Graeme J. Hankey, Joanna M. Wardlaw in Hankey's Clinical Neurology, 2020
Course of the musculocutaneous nerve: Arises from the lateral cord of the brachial plexus, carrying fibers from the C5 and C6 nerve roots.Passes through the axilla, pierces the coracobrachialis muscle (giving off branches to it), descends between the biceps and brachialis muscles, giving off branches to both parts of the biceps muscle and the brachialis muscle, and terminates as the lateral antebrachial cutaneous nerve.The sensory branch (lateral antebrachial cutaneous nerve) innervates the skin of the lateral aspect of the forearm from the elbow to the wrist.
Upper Limb
Rui Diogo, Drew M. Noden, Christopher M. Smith, Julia Molnar, Julia C. Boughner, Claudia Barrocas, Joana Bruno in Understanding Human Anatomy and Pathology, 2018
cutaneous nerve of the arm, and the medial cutaneous nerve of the forearm. The lateral cord logically gives rise to the lateral pectoral nerve (only to pectoralis major), and does not give rise to lateral cutaneous nerves of the arm and forearm because those of the forearm derive from the mus-culocutaneous nerve that bifurcates from this cord, while those of the arm derive from the axillary and radial nerves that bifurcate from the posterior cord (see Section 4.2.1.1). The upper, middle, and lower subscapular nerves branch from the posterior cord and perform the fourth and final “trick” (i.e., the “inferior trick’) listed above, running inferiorly and passing medially to the scapula, to innervate the group formed by the subscapularis, teres major, and latissimus dorsi. At the level of the scapula, the upper and lower subscapular nerves innervate the subscapularis. Then the middle (thoracodorsal) and lower nerves continue their descent inferiorly until they pass the inferior portion of the scapula to reach the more inferior and posterior (dorsal) muscles latissimus dorsi and teres major, respectively, thence the name “inferior trick” (Plate 4.7b) (Table 4.1).
Musculoskeletal system
Helen Butler, Neel Sharma, Tiago Villanueva in Student Success in Anatomy - SBAs and EMQs, 2022
32 The brachial plexus is formed from the C4–T1 roots. It divides into upper, middle and lower trunks, then lateral, posterior and medial cords. Which of the following nerves arise from the lateral cord? Ulnar nerveMusculocutaneous nerveAxillary nerveRadial nerveLong thoracic nerve
Superficial location of the brachial plexus and axillary artery in relation to pectoralis minor: a case report
Published in Southern African Journal of Anaesthesia and Analgesia, 2018
K Keet, G Louw
The brachial plexus innervates all the structures of the upper limb, and originates from spinal roots C5, C6, C7, C8 and T1, which are located between the anterior and middle scalene muscles.3 The trunks arise in the posterior triangle of the neck from the union of the roots; C5 and C6 roots join to form the superior trunk, C8 and T1 unite to form the inferior trunk, while C7 continues as the middle trunk. The trunks surround the first part of the axillary artery and pass over rib one, deep to the clavicle, where they each divide into anterior and posterior divisions. All three of the posterior divisions unite posterior to the axillary artery to form the posterior cord, the anterior divisions of the superior and middle trunk form the lateral cord on the lateral side of the axillary artery, while only the anterior division of the inferior trunk gives rise to the medial cord on the medial side of the artery. The cords are therefore named according to their position relative to the second part of the axillary artery and are situated deep to the pectoralis major and minor muscles. The terminal branches of the brachial plexus arise from the cords in the region of the third part of the axillary artery, inferior to the distal border of pectoralis minor, and supply skin and muscles of the upper limb.4 The lateral cord gives rise to the musculocutaneous nerve and the lateral root of the median nerve, the medial cord gives rise to the medial root of the median nerve and the ulnar nerve, and the posterior cord divides into the radial and axillary nerves.3
Everything pectoralis major: from repair to transfer
Published in The Physician and Sportsmedicine, 2020
Kamali Thompson, Young Kwon, Evan Flatow, Laith Jazrawi, Eric Strauss, Michael Alaia
The pectoralis major is a triangular muscle that lies anterior to the subscapularis and coracobrachialis and inferior to the deltoid [30]. It contains two heads: the superior clavicular head and the inferior sternocostal head. The clavicular head originates at the anterior border of the medial half of the clavicle, from which the fibers run laterally in a downward direction. It is innervated by the lateral pectoral nerve (C5-C7), which exits the lateral cord of the brachial plexus medial to the pectoralis minor, travels with the pectoral branch of thoracoacromial artery, and enters the pectoralis major at a mean of 12.5 cm medial to the humeral insertion (95% confidence interval 10–14.9 cm) [4,30,31]. The primary role of the clavicular head is forward flexion, adduction, and internal rotation of the humerus. The clavicular head is also partially responsible for abduction once the arm is abducted to 90° and adduction with the arm below 90°.
Can collagenase effectiveness in Dupuytren’s contracture be improved by using ultrasound-guided Injection? A comparative study
Published in Journal of Plastic Surgery and Hand Surgery, 2022
Luis Aguilella, Rosana Pérez-Giner, Victoria Higueras-Guerrero, Elena Belloch-Ramos, María Cuenca-Torres, Eva Llopis-San Juan
The selection of the point of injection, a relevant aspect in those patients who presented involvement of two joints of the same finger, was performed depending on the characteristics of the cords of the affected finger. In those patients where there was involvement of only one joint, MCP or PIP, the injection was made directly on the cord responsible for the contracture. However, when there was the involvement of two joints, to determine which cord was best suited for injection, in order to obtain the better clinical result with a single injection, the MCP hyperflexion manoeuvre was used, which highlights the dynamism in Dupuytren’s contracture described by Rodrigues [8]. If the performance of this manoeuvre (Figure 1) substantially improved the contracture of the PIP joint, which demonstrated its dependence on the pretendinous cord, then the injection was performed on that cord. If no reduction in the contracture of the PIP joint with the MCP hyperflexion manoeuvre was observed, which demonstrated its dependence on a phalangeal central or lateral cord, we opted to inject in the most affected joint. In this case, the patient was warned of the possibility of having to receive a second injection in order to extend the other joint. The total dose of CCH for each case was administered fractioned in three contiguous points of the same cord.
Related Knowledge Centers
- Axillary Artery
- Brachial Plexus
- Lateral Pectoral Nerve
- Median Nerve
- Musculocutaneous Nerve
- Axilla
- Posterior Cord
- Medial Cord