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Joints
A joint or articulation (or articular surface) is the connection made between bones, ossicles, or other hard structures in the body which link an animal's skeletal system into a functional whole.Saladin, Ken. Anatomy & Physiology. 7th ed. McGraw-Hill Connect. Webp.274/ref> They are constructed to allow for different degrees and types of movement. Some joints, such as the knee, elbow, and shoulder, are self-lubricating, almost frictionless, and are able to withstand compression and maintain heavy loads while still executing smooth and precise movements. Other joints such as suture (joint), sutures between the bones of the skull permit very little movement (only during birth) in order to protect the brain and the sense organs. The connection between a tooth and the jawbone is also called a joint, and is described as a fibrous joint known as a gomphosis. Joints are classified both structurally and functionally. Classification The number of joints depends on if Sesamoid bone, sesamoi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gomphosis
In anatomy, fibrous joints are joints connected by fibrous tissue, consisting mainly of collagen. These are fixed joints where bones are united by a layer of white fibrous tissue of varying thickness. In the skull the joints between the bones are called sutures. Such immovable joints are also referred to as synarthroses. Types Most fibrous joints are also called "fixed" or "immovable". These joints have no joint cavity and are connected via fibrous connective tissue. The skull bones are connected by fibrous joints called '' sutures''. In fetal skulls the sutures are wide to allow slight movement during birth. They later become rigid ( synarthrodial). Some of the long bones in the body such as the radius and ulna in the forearm are joined by a ''syndesmosis'' (along the interosseous membrane). Syndemoses are slightly moveable ( amphiarthrodial). The distal tibiofibular joint is another example. A ''gomphosis'' is a joint between the root of a tooth and the socket in the maxil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fibrous Joint
In anatomy, fibrous joints are joints connected by fibrous tissue, consisting mainly of collagen. These are fixed joints where bones are united by a layer of white fibrous tissue of varying thickness. In the skull the joints between the bones are called sutures. Such immovable joints are also referred to as synarthroses. Types Most fibrous joints are also called "fixed" or "immovable". These joints have no joint cavity and are connected via fibrous connective tissue. The skull bones are connected by fibrous joints called '' sutures''. In fetal skulls the sutures are wide to allow slight movement during birth. They later become rigid ( synarthrodial). Some of the long bones in the body such as the radius and ulna in the forearm are joined by a ''syndesmosis'' (along the interosseous membrane). Syndemoses are slightly moveable ( amphiarthrodial). The distal tibiofibular joint is another example. A ''gomphosis'' is a joint between the root of a tooth and the socket in the max ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Suture (joint)
In anatomy, fibrous joints are joints connected by fibrous tissue, consisting mainly of collagen. These are fixed joints where bones are united by a layer of white fibrous tissue of varying thickness. In the skull the joints between the bones are called sutures. Such immovable joints are also referred to as synarthroses. Types Most fibrous joints are also called "fixed" or "immovable". These joints have no joint cavity and are connected via fibrous connective tissue. The skull bones are connected by fibrous joints called '' sutures''. In fetal skulls the sutures are wide to allow slight movement during birth. They later become rigid ( synarthrodial). Some of the long bones in the body such as the radius and ulna in the forearm are joined by a ''syndesmosis'' (along the interosseous membrane). Syndemoses are slightly moveable ( amphiarthrodial). The distal tibiofibular joint is another example. A ''gomphosis'' is a joint between the root of a tooth and the socket in the max ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synovial Joint
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] |
Cartilaginous Joint
Cartilaginous joints are connected entirely by cartilage (fibrocartilage or hyaline). Cartilaginous joints allow more movement between bones than a fibrous joint but less than the highly mobile synovial joint. Cartilaginous joints also forms the growth regions of immature long bones and the intervertebral discs of the spinal column. __TOC__ Primary cartilaginous joints Primary cartilaginous joints are known as "synchondrosis". These bones are connected by hyaline cartilage and sometimes occur between ossification centers. This cartilage may ossify with age. Some examples of primary cartilaginous joints in humans are the "growth plates" between ossification centers in long bones. These joints here allow for only a little movement, such as in the spine or ribs. Secondary cartilaginous joints Secondary cartilaginous joints are known as "symphysis". These include fibrocartilaginous and hyaline joints, which usually occur at the midline. Some examples of secondary cartilagin ... [...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] |
Cartilaginous Joint
Cartilaginous joints are connected entirely by cartilage (fibrocartilage or hyaline). Cartilaginous joints allow more movement between bones than a fibrous joint but less than the highly mobile synovial joint. Cartilaginous joints also forms the growth regions of immature long bones and the intervertebral discs of the spinal column. __TOC__ Primary cartilaginous joints Primary cartilaginous joints are known as "synchondrosis". These bones are connected by hyaline cartilage and sometimes occur between ossification centers. This cartilage may ossify with age. Some examples of primary cartilaginous joints in humans are the "growth plates" between ossification centers in long bones. These joints here allow for only a little movement, such as in the spine or ribs. Secondary cartilaginous joints Secondary cartilaginous joints are known as "symphysis". These include fibrocartilaginous and hyaline joints, which usually occur at the midline. Some examples of secondary cartilagin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pivot Joint
In animal anatomy, a pivot joint (trochoid joint, rotary joint or lateral ginglymus) is a type of synovial joint whose movement axis is parallel to the long axis of the proximal bone, which typically has a convex articular surface. According to one classification system, a pivot joint like the other synovial joint —the hinge joint has one degree of freedom.Platzer, Werner (2008) ''Color Atlas of Human Anatomy'', Volume 1p.28/ref> Note that the degrees of freedom of a joint is not the same as the same as joint's range of motion. Movements Pivot joints allow for rotation, which can be external (for example when rotating an arm outward), or internal (as in rotating an arm inward). When rotating the forearm, these movements are typically called pronation and supination. In the standard anatomical position, the forearms are supinated, which means that the palms are facing forward, and the thumbs are pointing away from the body. In contrast, a forearm in pronation would have the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amphiarthrosis
Amphiarthrosis is a type of continuous, slightly movable joint. Types In amphiarthroses, the contiguous bony surfaces can be: * A symphysis: connected by broad flattened disks of fibrocartilage, of a more or less complex structure, which adhere to the ends of each bone, as in the articulations between the bodies of the vertebrae or the inferior articulation of the two hip bones (aka the pubic symphysis). * An interosseous membrane An interosseous membrane is a thick dense fibrous sheet of connective tissue that spans the space between two bones, forming a type of syndesmosis joint. Interosseous membranes in the human body: * Interosseous membrane of forearm * Interosseou ... - the sheet of connective tissue joining neighboring bones (e.g. tibia and fibula).Principles of Anatomy & Physiology, 12th Edition, Tortora & Derrickson, Pub: Wiley & Sons References External links * Joints {{musculoskeletal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Facet Joint
The facet joints (or zygapophysial joints, zygapophyseal, apophyseal, or Z-joints) are a set of synovial, plane joints between the articular processes of two adjacent vertebrae. There are two facet joints in each spinal motion segment and each facet joint is innervated by the recurrent meningeal nerves. Innervation Innervation to the facet joints vary between segments of the spinal, but they are generally innervated by medial branch nerves that come off the dorsal rami. It is thought that these nerves are for primary sensory input, though there is some evidence that they have some motor input local musculature. Within the cervical spine, most joints are innervated by the medial branch nerve (a branch of the dorsal rami) from the same levels. In other words, the facet joint between C4 and C5 vertebral segments is innervated by the C4 and C5 medial branch nerves. However, there are two exceptions: # The facet joint between C2 and C3 is innervated by the third occipital nerv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synarthrosis
A synarthrosis is a type of joint which allows no movement under normal conditions. Sutures and gomphoses are both synarthroses. Joints which allow more movement are called amphiarthroses or diarthroses. Syndesmoses joints are considered to be amphiarthrotic, because they allow a small amount of movement. Types They can be categorised by how the bones are joined together: *''Gomphosis'' is the type of joint in which a conical peg fits into a socket, for example, the socket of a tooth. Normally, there is very little movement of the teeth in the mandible or maxilla. *''Synostosis'' is where two bones that are initially separated eventually fuse, essentially becoming one bone. In humans, as in other animals, the plates of the cranium fuse with dense fibrous connective tissue as a child approaches adulthood.Principles of Anatomy & Physiology, 12th Edition, Tortora & Derrickson, Pub: Wiley & Sons Children whose cranial plates fuse too early may suffer deformities and brain damage as t ... [...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 * s * |
