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Supinator Muscle
In human anatomy, the supinator is a broad muscle in the posterior compartment of the forearm, curved around the upper third of the radius. Its function is to supinate the forearm. Structure Supinator consists of two planes of fibers, between which the deep branch of the radial nerve ls. The two planes arise in common — the superficial one by tendinous (the initial portion of the muscle is actually just tendon) and the deeper by muscular fibers —''Gray's Anatomy'' (1918), see infobox from the supinator crest of the ulna, the lateral epicondyle of humerus, the radial collateral ligament, and the annular radial ligament. The superficial fibers (''pars superficialis'') surround the upper part of the radius, and are inserted into the lateral edge of the radial tuberosity and the oblique line of the radius, as low down as the insertion of the pronator teres. The upper fibers (''pars profunda'') of the deeper plane form a sling-like fasciculus, which encircles the ne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lateral Epicondyle Of The Humerus
The lateral epicondyle of the humerus is a large, tuberculated eminence, curved a little forward, and giving attachment to the radial collateral ligament of the elbow joint, and to a tendon common to the origin of the supinator and some of the extensor muscles. Specifically, these extensor muscles include the anconeus muscle, the supinator, extensor carpi radialis brevis, extensor digitorum, extensor digiti minimi, and extensor carpi ulnaris. In birds, where the arm is somewhat rotated compared to other tetrapods, it is termed dorsal epicondyle of the humerus. In comparative anatomy, the term ''ectepicondyle'' is sometimes used. A common injury associated with the lateral epicondyle of the humerus is lateral epicondylitis also known as tennis elbow. Repetitive overuse of the forearm, as seen in tennis or other sports, can result in inflammation of "the tendons that join the forearm muscles on the outside of the elbow. The forearm muscles and tendons become damaged from overus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deep Branch Of The Radial Nerve
The radial nerve divides into a superficial (sensory) and deep (motor) branch at the cubital fossa. The deep branch of the radial nerve winds to the back of the forearm around the lateral side of the radius between the two planes of fibers of the Supinator, and is prolonged downward between the superficial and deep layers of muscles, to the middle of the forearm. The deep branch provides motor function to the muscles in the posterior compartment of the forearm, which is mostly the extensor muscles of the hand. The radial nerve arises from the posterior cord of the brachial plexus. The posterior cord takes nerves from the upper, lower, and middle trunk, so ultimately the radial nerve is formed from the anterior rami of C5 through T1. The radial nerve passes through the axilla, which makes it susceptible to injury. It can be compressed against the humerus by crutches, causing crutch paralysis. Symptoms of damage to the deep branch of the radial nerve typically include "wrist drop", ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biceps Brachii Muscle
The biceps or biceps brachii ( la, musculus biceps brachii, "two-headed muscle of the arm") is a large muscle that lies on the front of the upper arm between the shoulder and the elbow. Both heads of the muscle arise on the scapula and join to form a single muscle belly which is attached to the upper forearm. While the biceps crosses both the shoulder and elbow joints, its main function is at the elbow where it flexes the forearm and supinates the forearm. Both these movements are used when opening a bottle with a corkscrew: first biceps screws in the cork (supination), then it pulls the cork out (flexion). Structure The biceps is one of three muscles in the anterior compartment of the upper arm, along with the brachialis muscle and the coracobrachialis muscle, with which the biceps shares a nerve supply. The biceps muscle has two heads, the short head and the long head, distinguished according to their origin at the coracoid process and supraglenoid tubercle of the sc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abductor Pollicis Longus Muscle
In human anatomy, the abductor pollicis longus (APL) is one of the extrinsic muscles of the hand. Its major function is to abduct the thumb at the wrist. Its tendon forms the anterior border of the anatomical snuffbox. Structure The abductor pollicis longus lies immediately below the supinator and is sometimes united with it. It arises from the lateral part of the dorsal surface of the body of the ulna, below the insertion of the anconeus, from the interosseous membrane, and from the middle third of the dorsal surface of the body of the radius.''Gray's Anatomy'' (1918), see infobox Passing obliquely downward and lateralward, it ends in a tendon, which runs through a groove on the lateral side of the lower end of the radius, accompanied by the tendon of the extensor pollicis brevis. The insertion is divided into a distal, superficial part and a proximal, deep part. The superficial part is inserted with one or more tendons into the radial side of the base of the first meta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paralysis
Paralysis (also known as plegia) is a loss of motor function in one or more muscles. Paralysis can also be accompanied by a loss of feeling (sensory loss) in the affected area if there is sensory damage. In the United States, roughly 1 in 50 people have been diagnosed with some form of permanent or transient paralysis. The word "paralysis" derives from the Greek παράλυσις, meaning "disabling of the nerves" from παρά (''para'') meaning "beside, by" and λύσις (''lysis'') meaning "making loose". A paralysis accompanied by involuntary tremors is usually called "palsy". Causes Paralysis is most often caused by damage in the nervous system, especially the spinal cord. Other major causes are stroke, trauma with nerve injury, poliomyelitis, cerebral palsy, peripheral neuropathy, Parkinson's disease, ALS, botulism, spina bifida, multiple sclerosis, and Guillain–Barré syndrome. Temporary paralysis occurs during REM sleep, and dysregulation of this system can ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Posterior Interosseous Nerve
The posterior interosseous nerve (or dorsal interosseous nerve) is a nerve in the forearm. It is the continuation of the deep branch of the radial nerve, after this has crossed the supinator muscle. It is considerably diminished in size compared to the deep branch of the radial nerve. The nerve fibers originate from cervical segments C7 and C8 in the spinal column. Structure Course It descends along the interosseous membrane, anterior to the extensor pollicis longus muscle, to the back of the carpus, where it presents a gangliform enlargement from which filaments are distributed to the ligaments and articulations of the carpus. Supply The posterior interosseous nerve supplies all the muscles of the posterior compartment of the forearm, except anconeus muscle, brachioradialis muscle, and extensor carpi radialis longus muscle. In other words, it supplies the following muscles: * Extensor carpi radialis brevis muscle — deep branch of radial nerve * Extensor digitorum muscle * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arcade Of Frohse
Arcade of Frohse, sometimes called the supinator arch, is the most superior part of the superficial layer of the supinator muscle, and is a fibrous arch over the posterior interosseous nerve. The arcade of Frohse is a site of interosseous posterior nerve entrapment, and is believed to play a role in causing progressive paralysis of the posterior interosseous nerve, both with and without injury. The arcade of Frohse was named after German anatomist Anatomy () is the branch of biology concerned with the study of the structure of organisms and their parts. Anatomy is a branch of natural science that deals with the structural organization of living things. It is an old science, having it ..., Fritz Frohse (1871-1916). References External links Clinical anatomy of the radial nerveMRI Web Clinic (MRIs of Posterior interosseous nerve entrapment) Archade of Frohse {{muscle-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muscle Fascicle
A muscle fascicle is a bundle of skeletal muscle fibers surrounded by perimysium, a type of connective tissue. Structure Muscle cells are grouped into muscle fascicles by enveloping perimysium connective tissue. Fascicles are bundled together by epimysium connective tissue. Muscle fascicles typically only contain one type of muscle cell (either type I fibres or type II fibres), but can contain a mixture of both types. Function In the heart specialized cardiac muscle cells transmit electrical impulses from the atrioventricular node (AV node) to the Purkinje fibers – fascicles, also referred to as bundle branches. These start as a single fascicle of fibers at the AV node called the bundle of His that then splits into three bundle branches: the right fascicular branch, left anterior fascicular branch, and left posterior fascicular branch. Clinical significance Myositis may cause thickening of the muscle fascicles. This may be detected with ultrasound scans. Mu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pronator Teres
The pronator teres is a muscle (located mainly in the forearm) that, along with the pronator quadratus, serves to pronate the forearm (turning it so that the palm faces posteriorly when from the anatomical position). It has two attachments, to the medial humeral supracondylar ridge and the ulnar tuberosity, and inserts near the middle of the radius. Structure The pronator teres has two heads—humeral and ulnar. * The humeral head, the larger and more superficial, arises from the medial supracondylar ridge immediately superior to the medial epicondyle of the humerus, and from the common flexor tendon (which arises from the medial epicondyle). * The ulnar head (or ulnar tuberosity) is a thin fasciculus, which arises from the medial side of the coronoid process of the ulna, and joins the preceding at an acute angle. The median nerve enters the forearm between the two heads of the muscle, and is separated from the ulnar artery by the ulnar head. The muscle passes obliquely acros ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radial Tuberosity
Beneath the neck of the radius, on the medial side, is an eminence, the radial tuberosity; its surface is divided into: * a ''posterior, rough portion'', for the insertion of the tendon of the biceps brachii. * an ''anterior, smooth portion'', on which a bursa ( grc-gre, Προῦσα, Proûsa, Latin: Prusa, ota, بورسه, Arabic:بورصة) is a city in northwestern Turkey and the administrative center of Bursa Province. The fourth-most populous city in Turkey and second-most populous in the ... is interposed between the tendon and the bone. Ligaments that support the elbow joint also attach to the radial tuberosity. References External links * * () Additional images File:Sobo 1909 124.png, Radial tuberosity shown. File:Radius.jpg, Anterior View. Radial tuberosity. File:Radius2.jpg, Posterior View. Radial tuberosity. File:Radius_post.jpg, Radial tuberosity below neck. File:Radius_ant.jpg, Radial tuberosity below neck. File:Left_radius_-_close-up_-_animation. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anular Ligament Of Radius
The annular ligament (orbicular ligament) is a strong band of fibers that encircles the head of the radius, and retains it in contact with the radial notch of the ulna.''Gray's Anatomy'' (1918), see infobox Per '' Terminologia Anatomica 1998'', the spelling is "anular", but the spelling "annular" is frequently encountered. Indeed, the most recent version of ''Terminologia Anatomica'' (2019) uses "annular" as the preferred English spelling. Anatomy The annular ligament is attached by both its ends to the anterior and posterior margins of the radial notch of the ulna, together with which it forms the articular surface that surrounds the head and neck of the radius. The ligament is strong and well defined, yet its flexibility permits the slightly oval head of the radius to rotate freely during pronation and supination. The head of the radius is wider than the bone's neck, and, because the annular ligament embraces both, the radial head is "trapped" inside the ligament which thus a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radial Collateral Ligament (elbow)
The radial collateral ligament (RCL), lateral collateral ligament (LCL), or external lateral ligamentAs opposed to the "internal lateral ligament", better known as the medial or ulnar collateral ligament is a ligament in the elbow on the side of the radius. Structure The composition of the triangular ligamentous structure on the lateral side of the elbow varies widely between individuals, see alsFigure 4/ref> and can be considered either a single ligament, in which case multiple distal attachments are generally mentioned and the annular ligament is described separately, or as several separate ligaments, in which case parts of those ligaments are often described as indistinguishable from each other. In the latter case, the ligaments are collectively referred to as the lateral collateral ligament complex (LCLC), consisting of four ligaments: * the radial collateral ligament roper(RCL), from the lateral epicondyle to the annular ligament deep to the common extensor tendon * the la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
