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Extensor Tendon Compartments Of The Wrist
Extensor tendon compartments of the wrist are anatomical tunnels on the back of the wrist that contain tendons of muscles that extend (as opposed to flex) the wrist and the digits (fingers and thumb). The extensor tendons are held in place by the extensor retinaculum. As the tendons travel over the posterior (back) aspect of the wrist they are enclosed within synovial tendon sheaths. These sheaths reduce the friction to the extensor tendons as they traverse the compartments that are formed by the attachments of the extensor retinaculum to the distal (far end) of the radius and ulna. Structure The compartments are numbered with each compartment containing specific extensor tendons. Clinical significance Any of the dorsal compartments of the wrist can develop tenosynovial inflammation. The first compartment is the most frequently affected site, called De Quervain's disease (syndrome or tenosynovitis). The other two most commonly injured are the sixth (extensor carpi ulnaris) a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wrist
In human anatomy, the wrist is variously defined as (1) the Carpal bones, carpus or carpal bones, the complex of eight bones forming the proximal skeletal segment of the hand; "The wrist contains eight bones, roughly aligned in two rows, known as the carpal bones." (2) the wrist joint or radiocarpal joint, the joint between the radius (bone), radius and the Carpal bones, carpus and; (3) the anatomical region surrounding the carpus including the distal parts of the bones of the forearm and the proximal parts of the metacarpus or five metacarpal bones and the series of joints between these bones, thus referred to as ''wrist joints''. "With the large number of bones composing the wrist (ulna, radius, eight carpas, and five metacarpals), it makes sense that there are many, many joints that make up the structure known as the wrist." This region also includes the carpal tunnel, the anatomical snuff box, bracelet lines, the Flexor retinaculum of the hand, flexor retinaculum, and the ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extensor Pollicis Longus Muscle
In human anatomy, the extensor pollicis longus muscle (EPL) is a skeletal muscle located dorsally on the forearm. It is much larger than the extensor pollicis brevis, the origin of which it partly covers and acts to stretch the thumb together with this muscle. Structure The extensor pollicis longus arises from the dorsal surface of the ulna and from the interosseous membrane, next to the origins of abductor pollicis longus and extensor pollicis brevis. Passing through the third tendon compartment, lying in a narrow, oblique groove on the back of the lower end of the radius,''Gray's Anatomy'' 1918, see infobox it crosses the wrist close to the dorsal midline before turning towards the thumb using Lister's tubercle on the distal end of the radius as a pulley. It obliquely crosses the tendons of the extensores carpi radialis longus and brevis, and is separated from the extensor pollicis brevis by a triangular interval, the anatomical snuff box in which the radial artery is found. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intersection Syndrome
Intersection syndrome is a painful condition that affects the lateral side of the forearm when inflammation occurs at the intersection of the muscle bellies of the abductor pollicis longus and extensor pollicis brevis cross over the extensor carpi radialis longus and the extensor carpi radialis brevis. These 1st and 2nd dorsal muscle compartments intersect at this location, hence the name. The mechanism of injury is usually repetitive resisted extension, as with rowing, weight lifting, or pulling. Intersection syndrome is often confused with another condition called DeQuervain's syndrome De Quervain syndrome is mucoid degeneration of two tendons that control movement of the thumb and their tendon sheath. This results in pain and tenderness on the thumb side of the wrist. Radial abduction of the thumb is painful. On occasion, th ..., which is an irritation of the thumb-sided set of tendons at the wrist, called the first dorsal compartment. References External links {{muscu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tenosynovial Inflammation
Tenosynovitis is the inflammation of the fluid-filled sheath (called the synovium) that surrounds a tendon, typically leading to joint pain, swelling, and stiffness. Tenosynovitis can be either infectious or noninfectious. Common clinical manifestations of noninfectious tenosynovitis include de Quervain tendinopathy and stenosing tenosynovitis (more commonly known as trigger finger) Signs and symptoms Infectious tenosynovitis occurs between 2.5% and 9.4% of all hand infections. Kanavel's cardinal signs is used to diagnose infectious tenosynovitis. They are: tenderness to touch along the flexor aspect of the finger, fusiform enlargement of the affected finger, the finger being held in slight flexion at rest, and severe pain with passive extension. Fever may also be present but is uncommon. Pathogenesis Infectious tenosynovitis is the infection of closed synovial sheaths in the flexor tendons of the fingers. It is usually caused by trauma, but bacteria can spread from other sites ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extensor Carpi Ulnaris Muscle
In human anatomy, the extensor carpi ulnaris is a skeletal muscle located on the ulnar side of the forearm. The extensor carpi ulnaris acts to extend and adduct at the carpus/wrist from anatomical position. Being an extensor muscle, extensor carpi ulnaris is located on the posterior side of the forearm. Origin and insertion It originates from the lateral epicondyle of the humerus and the posterior border of the ulna, and crosses the forearm to the ulnar (medial) side to insert at the base of the 5th metacarpal. Action The extensor carpi ulnaris extends the wrist, but when acting alone inclines the hand toward the ulnar side; by its continued action it extends the elbow-joint. The muscle is a minor extensor of the carpus in carnivores, but has become a flexor in ungulates. In this case it would be described as ''ulnaris lateralis''. Innervation Despite its name, the extensor carpi ulnaris is innervated by the posterior interosseous nerve (C7 and C8), the continuation of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Distal Radioulnar Articulation
The distal radioulnar articulation (also known as the distal radioulnar joint, or inferior radioulnar joint) is a synovial pivot joint between the two bones in the forearm; the radius and ulna. It is one of two joints between the radius and ulna, the other being the proximal radioulnar articulation. The joint features an articular disc, and is reinforced by the palmar and dorsal radioulnar ligaments. Structure The distal radioulnar articulation is formed by the head of ulna, and the ulnar notch of the distal radius. Articular disc The joint features a triangular articular disc that is attached to the inferior margin of the ulnar notch by its base, and to a fossa at the base of the styloid process of the ulna by its apex. The articular disc acts to firmly bind the distal extremities of the two bones together. Ligaments The articulation is reinforced by the palmar radioulnar ligament, and dorsal radioulnar ligament. Function The function of the radioulnar joint is to li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extensor Digiti Minimi Muscle
The extensor digiti minimi (extensor digiti quinti proprius) is a slender muscle of the forearm, placed on the ulnar side of the extensor digitorum communis, with which it is generally connected. It arises from the common extensor tendon by a thin tendinous slip and frequently from the intermuscular septa between it and the adjacent muscles. Its tendon passes through a compartment of the extensor retinaculum, posterior to distal radio-ulnar joint, then divides into two as it crosses the dorsum of the hand, and finally joins the extensor digitorum tendon. All three tendons attach to the dorsal digital expansion of the fifth digit (little finger). There may be a slip of tendon to the fourth digit. Variations An additional fibrous slip from the lateral epicondyle; the tendon of insertion may not divide or may send a slip to the ring finger. Absence of muscle rare; fusion of the belly with the extensor digitorum communis The extensor digitorum muscle (also known as extensor dig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compartment Syndrome
Compartment syndrome is a condition in which increased pressure within one of the body's anatomical compartments results in insufficient blood supply to tissue within that space. There are two main types: acute and chronic. Compartments of the leg or arm are most commonly involved. Symptoms of acute compartment syndrome (ACS) can include severe pain, poor pulses, decreased ability to move, numbness, or a pale color of the affected limb. It is most commonly due to physical trauma such as a bone fracture (up to 75% of cases) or crush injury, but it can also be caused by acute exertion during sport. It can also occur after blood flow returns following a period of poor blood flow. Diagnosis is generally based upon a person's symptoms and may be supported by measurement of intracompartmental pressure before, during, and after activity. Normal compartment pressure should be within 12-18 mmHg; anything greater than that is considered abnormal and would need treatment. Treatment i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extensor Indicis Muscle
In human anatomy, the extensor indicis roprius'' is a narrow, elongated skeletal muscle in the deep layer of the dorsal forearm, placed medial to, and parallel with, the extensor pollicis longus. Its tendon goes to the index finger, which it extends. Structure It arises from the distal third of the dorsal part of the body of ulna and from the interosseous membrane. It runs through the fourth tendon compartment together with the extensor digitorum, from where it projects into the dorsal aponeurosis of the index finger. Opposite the head of the second metacarpal bone, it joins the ulnar side of the tendon of the extensor digitorum which belongs to the index finger. Like the extensor digiti minimi (i.e. the extensor of the little finger), the tendon of the extensor indicis runs and inserts on the ulnar side of the tendon of the common extensor digitorum. The extensor indicis lacks the juncturae tendinum interlinking the tendons of the extensor digitorum on the dorsal side of the h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extensor Digitorum Muscle
The extensor digitorum muscle (also known as extensor digitorum communis) is a muscle of the posterior forearm present in humans and other animals. It extends the medial four digits of the hand. Extensor digitorum is innervated by the posterior interosseous nerve, which is a branch of the radial nerve. Structure The extensor digitorum muscle arises from the lateral epicondyle of the humerus, by the common tendon; from the intermuscular septa between it and the adjacent muscles, and from the antebrachial fascia. It divides below into four tendons, which pass, together with that of the extensor indicis proprius, through a separate compartment of the dorsal carpal ligament, within a mucous sheath. The tendons then diverge on the back of the hand, and are inserted into the middle and distal phalanges of the fingers in the following manner.''Gray's anatomy'' (1918), see infobox Opposite the metacarpophalangeal articulation each tendon is bound by fasciculi to the collateral ligaments an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
