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Synovial Joints
A synovial joint, also known as diarthrosis, joins bones or cartilage with a fibrous joint capsule that is continuous with the periosteum of the joined bones, constitutes the outer boundary of a synovial cavity, and surrounds the bones' articulating surfaces. This joint unites long bones and permits free bone movement and greater mobility. The synovial cavity/joint is filled with synovial fluid. The joint capsule is made up of an outer layer of fibrous membrane, which keeps the bones together structurally, and an inner layer, the synovial membrane, which seals in the synovial fluid. They are the most common and most movable type of joint in the body of a mammal. As with most other joints, synovial joints achieve movement at the point of contact of the articulating bones. Structure Synovial joints contain the following structures: * Synovial cavity: all diarthroses have the characteristic space between the bones that is filled with synovial fluid * Joint capsule: the fibrous ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 another bone. The distal bone is capable of motion around an indefinite number of axes, which have one common center. This enables the joint to move in many directions. An enarthrosis is a special kind of spheroidal joint in which the socket covers the sphere beyond its equator.Platzer, Werner (2008) ''Color Atlas of Human Anatomy'', Volume 1p.28/ref> Examples Examples of this form of articulation are found in the hip, where the round head of the femur (ball) rests in the cup-like acetabulum (socket) of the pelvis; and in the shoulder joint, where the rounded upper extremity of the humerus (ball) rests in the cup-like glenoid fossa (socket) of the shoulder blade.And the phalanges (toes, fingers)Introduction to Joints: Synovial Joints - Ball and Socket Joints (The shoulder also includes a sternoclavicular joint ... [...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" 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 * Triangular fibrocartilage ("articular disk of the distal radioulnar articulation") * Articular disk of the temporomandibular joint * Articular disk of sternoclavicular articulation The articular disc of the sternoclavicular joint is flat and nearly circula ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elbow-joint
The elbow is the region between the 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 medial epicondyles of the humerus. The elbow joint is a hinge joint between the arm and the forearm; more specifically between the humerus in the upper arm and the radius and ulna in the forearm which allows the forearm and hand to be moved towards and away from the body. The term ''elbow'' is specifically used for humans and other primates, and in other vertebrates forelimb plus joint is used. The name for the elbow in Latin is ''cubitus'', and so the word cubital is used in some elbow-related terms, as in ''cubital nodes'' for example. Structure Joint The elbow joint has three different portions surrounded by a common joint capsule. These are joints between the three bones of the elbow, the humerus of the upper arm, and the radius and th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acromioclavicular Joint
The acromioclavicular joint, or AC joint, is a joint at the top of the shoulder. It is the junction between the acromion (part of the scapula that forms the highest point of the shoulder) and the clavicle. It is a plane synovial joint. Structure Ligaments The joint is stabilized by three ligaments: * The acromioclavicular ligament, which attaches the clavicle to the acromion of the scapula. Superior Acromioclavicular Ligament This ligament is a quadrilateral band, covering the superior part of the articulation, and extending between the upper part of the lateral end of the clavicle and the adjoining part of the upper surface of the acromion. It is composed of parallel fibers, which interlace with the aponeuroses of the Trapezius and Deltoideus; below, it is in contact with the articular disk when this is present. Inferior Acromioclavicular Ligament This ligament is somewhat thinner than the preceding; it covers the under part of the articulation, and is attached to the adjoi ... [...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] |
Carpal
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. When c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anastomosis
An anastomosis (, plural anastomoses) is a connection or opening between two things (especially cavities or passages) that are normally diverging or branching, such as between blood vessels, leaf#Veins, leaf veins, or streams. Such a connection may be normal (such as the foramen ovale (heart), foramen ovale in a fetus's heart) or abnormal (such as the atrial septal defect#Patent foramen ovale, patent foramen ovale in an adult's heart); it may be acquired (such as an arteriovenous fistula) or innate (such as the arteriovenous shunt of a metarteriole); and it may be natural (such as the aforementioned examples) or artificial (such as a surgical anastomosis). The reestablishment of an anastomosis that had become blocked is called a reanastomosis. Anastomoses that are abnormal, whether congenital disorder, congenital or acquired, are often called fistulas. The term is used in medicine, biology, mycology, geology, and geography. Etymology Anastomosis: medical or Modern Latin, from Gre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gosselin Fracture
The Gosselin fracture is a V-shaped fracture of the distal tibia which extends into the ankle joint and fractures the tibial plafond into anterior and posterior fragments. The fracture was described by Leon Athanese Gosselin, chief of surgery at the Hôpital de la Charité Hôpital de la Charité (, "Charity Hospital") was a hospital in Paris founded in the 17th century and closed in 1935. History In 1606, Marie de Médicis invited the Brothers Hospitallers of St. John of God to come to France. The Abbot of Sai ... in Paris.Gosselin LA, Stimson LA. ''translated in Clinical lectures on surgery.'' Philadelphia, Pa. Lea, 1878. References External links {{orthopedics-stub Bone fractures ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Talocrural Joint
The ankle, or the talocrural region, or the jumping bone (informal) is the area where the foot and the human leg, leg meet. The ankle includes three joints: the ankle joint proper or talocrural joint, the subtalar joint, and the inferior tibiofibular joint. The movements produced at this joint are dorsiflexion and plantarflexion of the foot. In common usage, the term ankle refers exclusively to the ankle region. In medical terminology, "ankle" (without qualifiers) can refer broadly to the region or specifically to the talocrural joint. The main bones of the ankle region are the talus bone, talus (in the foot), and the tibia and fibula (in the leg). The talocrural joint is a Synovial joint, synovial hinge joint that connects the distal ends of the tibia and fibula in the lower limb with the proximal end of the talus. The articulation between the tibia and the talus bears more weight than that between the smaller fibula and the talus. Structure Region The ankle region is found at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Collagen Fibers
Type I collagen is the most abundant collagen of the human body. It forms large, eosinophilic fibers known as collagen fibers. It is present in scar tissue, the end product when tissue heals by repair, as well as tendons, ligaments, the endomysium of myofibrils, the organic part of bone, the dermis, the dentin, and organ capsules. Formation The gene produces the pro-alpha1(I) chain. This chain combines with another pro-alpha1(I) chain and also with a pro-alpha2(I) chain (produced by the gene) to make a molecule of type I pro-collagen. These triple-stranded, rope-like pro-collagen molecules must be processed by enzymes outside the cell. Once these molecules are processed, they arrange themselves into long, thin fibrils that cross-link to one another in the spaces around cells. The cross-links result in the formation of very strong mature type I collagen fiber. Clinical significance See Collagen, type I, alpha 1#Clinical significance Markers used to measure bone loss are not ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dense Regular Connective Tissue
Dense regular connective tissue (DRCT) provides connection between different tissues in the human body. The collagen fibers in dense regular connective tissue are bundled in a parallel fashion. DRCT is divided into white fibrous connective tissue and yellow fibrous connective tissue, both of which occur in two forms: cord arrangement and sheath arrangement. In cord arrangement, bundles of collagen and matrix are distributed in regular alternate patterns. In sheath arrangement, collagen bundles and matrix are distributed in irregular patterns, sometimes in the form of a network. It is similar to areolar tissue, but in DRCT elastic fibers are completely absent. Structures formed * An example of their use is in tendons, which connect muscle to bone and derive their strength from the regular, longitudinal arrangement of bundles of collagen fibers. * Ligaments bind bone to bone and are similar in structure to tendons. * Aponeuroses An aponeurosis (; plural: ''aponeuroses'') is a type ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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