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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 (carpus) that connects the hand to the forearm. The terms "carpus" and "carpal" are derived from the Latin wikt:carpus#Latin, carpus and the Greek language, Greek wikt:καρπός#Ancient Greek, καρπός (karpós), meaning "wrist". In human anatomy, the main role of the carpal bones is to joint, articulate with the radius (bone), radial and ulnar heads to form a highly mobile condyloid joint (i.e. wrist joint),Kingston 2000, pp 126-127 to provide attachments for thenar and hypothenar muscles, and to form part of the rigid carpal tunnel which allows the median nerve and tendons of the anterior compartment of the forearm, anterior forearm muscles to be transmitted to the hand and fingers. In tetrapods, the carpus is the sole cluster of bones in the wrist between the radius (bone), radius and ulna and the metacarpus. The bones of the carpus do not belong to individual fingers (or toes in quadrupeds), whereas those ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metacarpus
In human anatomy, the metacarpal bones or metacarpus, also known as the "palm bones", are the appendicular skeleton, appendicular bones that form the intermediate part of the hand between the phalanges (fingers) and the carpal bones (wrist, wrist bones), which joint, articulate with the forearm. The metacarpal bones are homologous 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-indepen ... [...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 ulna varies from 2 to 6 mm in length. 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 unstable ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Forearm
The forearm is the region of the upper limb between the elbow and the wrist. The term forearm is used in anatomy to distinguish it from the arm, a word which is used to describe the entire appendage of the upper limb, but which in anatomy, technically, means only the region of the upper arm, whereas the lower "arm" is called the forearm. It is homologous to the region of the leg that lies between the knee and the ankle joints, the crus. The forearm contains two long bones, the radius and the ulna, forming the two radioulnar joints. The interosseous membrane connects these bones. Ultimately, the forearm is covered by skin, the anterior surface usually being less hairy than the posterior surface. The forearm contains many muscles, including the flexors and extensors of the wrist, flexors and extensors of the digits, a flexor of the elbow ( brachioradialis), and pronators and supinators that turn the hand to face down or upwards, respectively. In cross-section, the forearm can ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ligament
A ligament is a type of fibrous connective tissue in the body that connects bones to other bones. It also connects flight feathers to bones, in dinosaurs and birds. All 30,000 species of amniotes (land animals with internal bones) have ligaments. It is also known as ''articular ligament'', ''articular larua'', ''fibrous ligament'', or ''true ligament''. Comparative anatomy 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 regeneration of periodontist ligament. The study of ligaments is known as . Humans Other ligame ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Articular Disc
The articular disc (or disk) 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 Synovial fluid, also called synovia, elp 1/sup> is a viscous, non-Newtonian fluid found in the cavities of synovial joints. With its egg white–like consistency, the principal role of synovial fluid is to reduce friction between the articul ... to areas of the articular cartilage that experience the most friction. The term " meniscus" 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 * ... [...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 * metacarpophalangeal joints * metatarsophalangeal joints * atlanto-occipital joints These are also called ellipsoid joints. The oval-shaped condyle of one bone fits into the elliptical cavity of the other bone. These joints allow biaxial movements — i.e., forward and backward, or from side to side, but not rotation. Radiocarpal joint and metacarpophalangeal joint are examples of condyloid joints. An example of an Ellipsoid joint is the wrist; it functions similarly to the ball and socket joint The ball-and-socket joint (or spheroid joint) is a type of synovial joint in which the ball-shaped surface of one rounded bone fits into the cup-like depression of anoth ... [...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] |
Pronation
Motion, the process of movement, is described using specific anatomical terminology, anatomical terms. Motion includes movement of Organ (anatomy), organs, joints, Limb (anatomy), 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. Anatomy, 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'', descri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proximal Radioulnar Joint
The proximal radioulnar articulation, also known as the proximal radioulnar joint (PRUJ), is a synovial pivot joint between the circumference of the head of the radius and the ring formed by the radial notch of the ulna and the annular ligament. Structure The proximal radioulnar joint is a synovial pivot joint. It occurs between the circumference of the head of the radius and the ring formed by the radial notch of the ulna and the annular ligament. The interosseous membrane of the forearm and the annular ligament stabilise the joint. A number of nerves run close to the proximal radioulnar joint, including: *median nerve *musculocutaneous nerve *radial nerve See also * Distal radioulnar articulation * 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 relativ ... Referen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
