|
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 The supinator consists of two planes of fibers, between which passes the deep branch of the radial nerve. The two planes arise in common—the superficial one originating as tendons and the deeper by muscular fibers—from the supinator crest of the ulna, the lateral epicondyle of the 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 neck of the radius above the tuberosity and is attached to the back part of its medial surfac ... [...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 overu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supination
Motion, the process of movement, is described using specific anatomical terms. Motion includes movement of organs, joints, limbs, and specific sections of the body. The terminology used describes this motion according to its direction relative to the anatomical position of the body parts involved. Anatomists and others use a unified set of terms to describe most of the movements, although other, more specialized terms are necessary for describing unique movements such as those of the hands, feet, and eyes. In general, motion is classified according to the anatomical plane it occurs in. ''Flexion'' and ''extension'' are examples of ''angular'' motions, in which two axes of a joint are brought closer together or moved further apart. ''Rotational'' motion may occur at other joints, for example the shoulder, and are described as ''internal'' or ''external''. Other terms, such as ''elevation'' and ''depression'', describe movement above or below the horizontal plane. Many anatomic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biceps Brachii Muscle
The biceps or 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 Muscle head, 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 long head of the biceps crosses both the shoulder and elbow joints, its main function is at the elbow where it flexes and supination, 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 Fascial compartments of arm#Anterior compartment, 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 cor ... [...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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paralysis
Paralysis (: paralyses; also known as plegia) is a loss of Motor skill, motor function in one or more Skeletal muscle, 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 language, 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, Physical trauma, trauma with nerve injury, poliomyelitis, cerebral palsy, peripheral neuropathy, Parkinson's disease, ALS, botulism, spina bifida, multiple sclerosis and Guillain–Barré syndrome. Incidents th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Posterior Interosseous Nerve
The posterior interosseous nerve (or dorsal interosseous nerve/deep radial 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 * Ext ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radial Nerve
The radial nerve is a nerve in the human body that supplies the posterior portion of the upper limb. It innervates the medial and lateral heads of the triceps brachii muscle of the arm, as well as all 12 muscles in the Posterior compartment of the forearm, posterior osteofascial compartment of the forearm and the associated joints and overlying skin. It originates from the brachial plexus, carrying fibers from the posterior roots of spinal nerves C5, C6, C7, C8 and T1. The radial nerve and its branches provide Motor neuron, motor innervation to the dorsal arm muscles (the triceps brachii and the anconeus) and the extrinsic extensors of the wrists and hands; it also provides cutaneous Nerve supply to the skin, sensory innervation to most of the back of the hand, except for the back of the little finger and adjacent half of the ring finger (which are innervated by the ulnar nerve). The radial nerve divides into a deep branch, which becomes the posterior interosseous nerve, and a su ... [...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 morphology concerned with the study of the internal 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 scien ..., 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. ... [...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 origins, at the medial humeral supracondylar ridge and the medial side of the coronoid process of the ulna 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. T ... [...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 is interposed between the tendon and the bone. Ligaments that support the elbow joint The elbow is the region between the upper arm and the forearm that surrounds the elbow joint. The elbow includes prominent landmarks such as the olecranon, the cubital fossa (also called the chelidon, or the elbow pit), and the lateral and the ... 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. Structure 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 thu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
