|
Medial Pectoral Nerve
The medial pectoral nerve (also known as the medial anterior thoracic nerve) is (typically) a branch of the medial cord of the brachial plexus and is derived from spinal nerve roots C8-T1. It provides motor innervation to the pectoralis minor muscle, and the lower half (sternal part) of the pectoralis major muscle. It runs along the inferior border of the pectoralis minor muscle. Damage to the medial pectoral nerve can result in inability to elevate the shoulder. Anatomy Origin The medial pectoral nerve usually arises from the medial cord of the brachial plexus; it can however occasionally arise directly from the anterior division of the inferior trunk of the brachial plexus. It is derived from the eighth cervical (C8) and first thoracic (T1) spinal nerve roots. The origin is situated posterior to the axillary artery. Course and relations It passes behind the first part of the axillary artery, curves forward between the axillary artery and vein, and unites in front of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pectoralis Minor Muscle
Pectoralis minor muscle () is a thin, triangular muscle, situated at the upper part of the chest, beneath the pectoralis major in the human body. It arises from ribs III-V; it inserts onto the coracoid process of the scapula. It is innervated by the medial pectoral nerve. Its function is to stabilise the scapula by holding it fast in position against the Thoracic wall, chest wall. Structure Attachments From the muscle's origin, the muscle's fibers pass superiorly and laterally, converging to form a flat tendon. Origin Pectoralis minor muscle arises from the upper margins and outer surfaces of the 3rd, 4th, and 5th ribs near their costal cartilages, and from the Aponeurosis, aponeuroses covering the External intercostal muscles, intercostalis. Insertion Its tendon inserts onto the medial border and upper surface of the coracoid process of the scapula. Innervation The muscle receives motor innervation from the medial pectoral nerve. Relations Pectoralis minor muscle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Axillary Artery
In human anatomy, the axillary artery is a large blood vessel that conveys oxygenated blood to the lateral aspect of the thorax, the axilla (armpit) and the upper limb. Its origin is at the lateral margin of the first rib, before which it is called the subclavian artery. After passing the lower margin of teres major muscle, teres major it becomes the brachial artery. Structure The axillary artery is often referred to as having three parts, with these divisions based on its location relative to the pectoralis minor muscle, which is superficial to the artery. * First part – the part of the artery superior to the pectoralis minor * Second part – the part of the artery posterior to the pectoralis minor * Third part – the part of the artery inferior to the pectoralis minor. Relations The axillary artery is accompanied by the axillary vein, which lies medial to the artery, along its length. In the axilla, the axillary artery is surrounded by the brachial plexus. The second ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lateral Pectoral Nerve
The lateral pectoral nerve (also known as the lateral anterior thoracic nerve) arises from the lateral cord of the brachial plexus, and through it from the C5-7. It passes across the axillary artery and vein, pierces the clavipectoral (coracoclavicular) fascia, and enters the deep surface of the pectoralis major to innervate it. Function The lateral pectoral nerve provides motor innervation to the pectoralis major muscle. Although this nerve is described as mostly motor, it also has been considered to carry proprioceptive and nociceptive fibers. It arises either from the lateral cord or directly from the anterior divisions of the upper and middle trunks of the brachial plexus. This is unlike the medial pectoral nerve, which derives from the medial cord (or directly from the anterior division of the lower trunk). It splits into four to seven branches that pierce the clavipectoral fascia to innervate the entire pectoralis major or its superior portion. The medial and latera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Axillary Nerve
The axillary nerve or the circumflex nerve is a nerve of the human body, that originates from the brachial plexus ( upper trunk, posterior division, posterior cord) at the level of the axilla (armpit) and carries nerve fibers from C5 and C6. The axillary nerve travels through the quadrangular space with the posterior circumflex humeral artery and vein to innervate the deltoid and teres minor. Structure The nerve lies at first behind the axillary artery, and in front of the subscapularis, and passes downward to the lower border of that muscle. It then winds from anterior to posterior around the neck of the humerus, in company with the posterior humeral circumflex artery, through the quadrangular space (bounded above by the teres minor, below by the teres major, medially by the long head of the triceps brachii, and laterally by the surgical neck of the humerus), and divides into an anterior, a posterior, and a collateral branch to the long head of the triceps brachii bra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pectoralis Minor
Pectoralis minor muscle () is a thin, triangular muscle, situated at the upper part of the chest, beneath the pectoralis major in the human body. It arises from ribs III-V; it inserts onto the coracoid process of the scapula. It is innervated by the medial pectoral nerve. Its function is to stabilise the scapula by holding it fast in position against the chest wall. Structure Attachments From the muscle's origin, the muscle's fibers pass superiorly and laterally, converging to form a flat tendon. Origin Pectoralis minor muscle arises from the upper margins and outer surfaces of the 3rd, 4th, and 5th ribs near their costal cartilages, and from the aponeuroses covering the intercostalis. Insertion Its tendon inserts onto the medial border and upper surface of the coracoid process of the scapula. Innervation The muscle receives motor innervation from the medial pectoral nerve. Relations Pectoralis minor muscle forms part of the anterior wall of the axilla. It is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lateral Pectoral Nerve
The lateral pectoral nerve (also known as the lateral anterior thoracic nerve) arises from the lateral cord of the brachial plexus, and through it from the C5-7. It passes across the axillary artery and vein, pierces the clavipectoral (coracoclavicular) fascia, and enters the deep surface of the pectoralis major to innervate it. Function The lateral pectoral nerve provides motor innervation to the pectoralis major muscle. Although this nerve is described as mostly motor, it also has been considered to carry proprioceptive and nociceptive fibers. It arises either from the lateral cord or directly from the anterior divisions of the upper and middle trunks of the brachial plexus. This is unlike the medial pectoral nerve, which derives from the medial cord (or directly from the anterior division of the lower trunk). It splits into four to seven branches that pierce the clavipectoral fascia to innervate the entire pectoralis major or its superior portion. The medial and latera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Axillary Vein
In human anatomy, the axillary vein is a large blood vessel that conveys blood from the lateral aspect of the thorax, axilla (armpit) and upper limb toward the heart. There is one axillary vein on each side of the body. Structure Its origin is at the lower margin of the teres major muscle and a continuation of the brachial vein. This large vein is formed by the brachial vein and the basilic vein. At its terminal part, it is also joined by the cephalic vein. Other tributaries include the subscapular vein, circumflex humeral vein, lateral thoracic vein and thoraco-acromial vein. It terminates at the lateral margin of the first rib, at which it becomes the subclavian vein. It is accompanied along its course by a similarly named artery, the axillary artery In human anatomy, the axillary artery is a large blood vessel that conveys oxygenated blood to the lateral aspect of the thorax, the axilla (armpit) and the upper limb. Its origin is at the lateral margin of the fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thoracic Vertebrae
In vertebrates, thoracic vertebrae compose the middle segment of the vertebral column, between the cervical vertebrae and the lumbar vertebrae. In humans, there are twelve thoracic vertebra (anatomy), vertebrae of intermediate size between the cervical and lumbar vertebrae; they increase in size going towards the lumbar vertebrae. They are distinguished by the presence of Zygapophysial joint, facets on the sides of the bodies for Articulation (anatomy), articulation with the head of rib, heads of the ribs, as well as facets on the transverse processes of all, except the eleventh and twelfth, for articulation with the tubercle (rib), tubercles of the ribs. By convention, the human thoracic vertebrae are numbered T1–T12, with the first one (T1) located closest to the skull and the others going down the spine toward the lumbar region. General characteristics These are the general characteristics of the second through eighth thoracic vertebrae. The first and ninth through twelfth v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cervical Vertebrae
In tetrapods, cervical vertebrae (: vertebra) are the vertebrae of the neck, immediately below the skull. Truncal vertebrae (divided into thoracic and lumbar vertebrae in mammals) lie caudal (toward the tail) of cervical vertebrae. In sauropsid species, the cervical vertebrae bear cervical ribs. In lizards and saurischian dinosaurs, the cervical ribs are large; in birds, they are small and completely fused to the vertebrae. The vertebral transverse processes of mammals are homologous to the cervical ribs of other amniotes. Most mammals have seven cervical vertebrae, with the only three known exceptions being the manatee with six, the two-toed sloth with five or six, and the three-toed sloth with nine. In humans, cervical vertebrae are the smallest of the true vertebrae and can be readily distinguished from those of the thoracic or lumbar regions by the presence of a transverse foramen, an opening in each transverse process, through which the vertebral artery, verteb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
