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Carpus
In human anatomy, the wrist is variously defined as (1) the 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 and the 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, and the extensor retinaculum. As a consequence of these various definitions, fra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carpal Bones
The carpal bones are the eight small bones that make up the wrist (or carpus) that connects the hand to the forearm. The term "carpus" is derived from the Latin carpus and the Greek καρπός (karpós), meaning "wrist". In human anatomy, the main role of the wrist is to facilitate effective positioning of the hand and powerful use of the extensors and flexors of the forearm, and the mobility of individual carpal bones increase the freedom of movements at the wrist.Kingston 2000, pp 126-127 In tetrapods, the carpus is the sole cluster of bones in the wrist between the radius and ulna and the metacarpus. The bones of the carpus do not belong to individual fingers (or toes in quadrupeds), whereas those of the metacarpus do. The corresponding part of the foot is the tarsus. The carpal bones allow the wrist to move and rotate vertically. Structure Bones The eight carpal bones may be conceptually organized as either two transverse rows, or three longitudinal columns. Wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metacarpus
In human anatomy, the metacarpal bones or metacarpus form the intermediate part of the skeletal hand located between the phalanges of the fingers and the carpal bones of the wrist, which forms the connection to the forearm. The metacarpal bones are analogous to the metatarsal bones in the foot. Structure The metacarpals form a transverse arch to which the rigid row of distal carpal bones are fixed. The peripheral metacarpals (those of the thumb and little finger) form the sides of the cup of the palmar gutter and as they are brought together they deepen this concavity. The index metacarpal is the most firmly fixed, while the thumb metacarpal articulates with the trapezium and acts independently from the others. The middle metacarpals are tightly united to the carpus by intrinsic interlocking bone elements at their bases. The ring metacarpal is somewhat more mobile while the fifth metacarpal is semi-independent.Tubiana ''et al'' 1998, p 11 Each metacarpal bone consists of a bod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ulnar Styloid Process
The styloid process of the ulna is a bony prominence found at distal end of the ulna in the forearm. Structure The styloid process of the ulna projects from the medial and back part of the ulna. It descends a little lower than the head. The head is separated from the styloid process by a depression for the attachment of the apex of the triangular articular disk, and behind, by a shallow groove for the tendon of the extensor carpi ulnaris muscle. The styloid process of the ulnar varies in length between 2 mm and 6 mm. Function The rounded end of the styloid process of the ulna connects to the ulnar collateral ligament of the wrist. The radioulnar ligaments also attaches to the base of the styloid process of the ulna. Clinical significance Fractures of the styloid process of the ulna seldom require treatment when they occur in association with a distal radius fracture. The major exception is when the joint between these bones, the distal radioulnar joint (or DRUJ), is uns ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ulnar Notch Of The Radius
The articular surface for the ulna is called the ulnar notch (sigmoid cavity) of the radius In classical geometry, a radius ( : radii) of a circle or sphere is any of the line segments from its center to its perimeter, and in more modern usage, it is also their length. The name comes from the latin ''radius'', meaning ray but also the ...; it is in the distal radius, and is narrow, concave, smooth, and articulates with the head of the ulna forming the distal radioulnar joint. References Radius (bone) {{musculoskeletal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radial Collateral Ligament (wrist)
The radial collateral ligament (external lateral ligament, radial carpal collateral ligament) extends from the tip of the styloid process of the radius and attaches to the radial side of the scaphoid (formerly Navicular bone of the hand), immediately adjacent to its proximal articular surface and some fibres extend to the lateral side of the trapezium (greater multangular bone). It is in relation with the radial artery, which separates the ligament from the tendons of the Abductor pollicis longus and Extensor pollicis brevis. The radial collateral ligament's role is to limit ulnar deviation Ulnar deviation, also known as ulnar drift, is a hand deformity in which the swelling of the metacarpophalangeal joints (the big knuckles at the base of the fingers) causes the fingers to become displaced, tending towards the little finger. Its n ... at the wrist. References External links * * http://classes.kumc.edu/sah/resources/handkines/ligaments/wvsradcoll.htm Ligaments Liga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ulnar Collateral Ligament (wrist)
The ulnar collateral ligament (internal lateral ligament, ulnar carpal collateral ligament or ulnar collateral ligament of the wrist joint) is a rounded cord, attached above to the end of the styloid process of the ulna The ulna (''pl''. ulnae or ulnas) is a long bone found in the forearm that stretches from the elbow to the smallest finger, and when in anatomical position, is found on the medial side of the forearm. That is, the ulna is on the same side of t ..., and dividing below into two fasciculi, one of which is attached to the medial side of the triquetral bone, the other to the pisiform and flexor retinaculum. References Ligaments of the upper limb {{Portal bar, Anatomy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dorsal Radiocarpal Ligament
The dorsal radiocarpal ligament (posterior ligament) is less thick and strong than its volar counterpart, and has a proximal attachment to the posterior border of the distal radius. Its fibers run medially and inferiorly to form a distal attachment at the dorsal surfaces of the scaphoid (navicular bone of the hand), lunate, and triquetral. The fibres of the dorsal radiocarpal ligament blend with those of the dorsal intercarpal ligament. It is in relation, behind, with the Extensor tendons of the finger A finger is a limb of the body and a type of digit, an organ of manipulation and sensation found in the hands of most of the Tetrapods, so also with humans and other primates. Most land vertebrates have five fingers (Pentadactyly). Chambers 1 ...s; in front, it is blended with the articular disk. External links * This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained herein may be outdated. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palmar Radiocarpal Ligament
The palmar radiocarpal ligament (anterior ligament, volar radiocarpal ligament) is a broad membranous band, attached above to the distal end of the Radius (bone), radius, and passing downward to the scaphoid, lunate, Triquetral bone, triquetrum and capitate of the carpal bones in the wrist. In addition to this broad membrane, there is a rounded wikt:fasciculus, fasciculus, superficial to the rest, which reaches from the base of the styloid process of the ulna to the lunate and triangular bones. Perforations The ligament is perforated by apertures for the passage of vessels, Relations It is in relation, in front, with the tendons of the flexor digitorum profundus and flexor pollicis longus. Behind, it is closely adherent to the anterior border of the articular disk of the distal radioulnar articulation. Components Some sources break down the components of the ligament as follows: radiolunate, radiocapitate, radiotriquetral, and radioscaphoid. Other sources combine the radioscap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ligament
A ligament is the fibrous connective tissue that connects bones to other bones. It is also known as ''articular ligament'', ''articular larua'', ''fibrous ligament'', or ''true ligament''. Other ligaments in the body include the: * Peritoneal ligament: a fold of peritoneum or other membranes. * Fetal remnant ligament: the remnants of a fetal tubular structure. * Periodontal ligament: a group of fibers that attach the cementum of teeth to the surrounding alveolar bone. Ligaments are similar to tendons and fasciae as they are all made of connective tissue. The differences among them are in the connections that they make: ligaments connect one bone to another bone, tendons connect muscle to bone, and fasciae connect muscles to other muscles. These are all found in the skeletal system of the human body. Ligaments cannot usually be regenerated naturally; however, there are periodontal ligament stem cells located near the periodontal ligament which are involved in the adult ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Articular Disc
The articular disk (or disc) is a thin, oval plate of fibrocartilage present in several joints which separates synovial cavities. This separation of the cavity space allows for separate movements to occur in each space. The presence of an articular disk also permits a more even distribution of forces between the articulating surfaces of bones, increases the stability of the joint, and aids in directing the flow of synovial fluid to areas of the articular cartilage that experience the most friction. The term "meniscus Meniscus may refer to: * Meniscus (anatomy), crescent-shaped fibrocartilaginous structure that partly divides a joint cavity * Meniscus (liquid), a curve in the upper surface of liquid contained in an object *Meniscus (optics) A lens is a ..." has a very similar meaning. Additional images File:Gray325.png, Sternoclavicular articulation. Anterior view. File:Gray300.png , Diagrammatic section of a diarthrodial joint, with an articular disk. See also * Tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Condyloid Joint
A condyloid joint (also called condylar, ellipsoidal, or bicondylar) is an ovoid articular surface, or condyle that is received into an elliptical cavity. This permits movement in two planes, allowing flexion, extension, adduction, abduction, and circumduction. Examples Examples include: * the wrist-joint * s * metatarsophalangeal joints * [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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