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Ligaments Of The Head And Neck
A ligament is a type of Connective tissue#Types, fibrous connective tissue in the body that connects bones to other bones. It also connects Flight_feather#Remiges, 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 li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plural
In many languages, a plural (sometimes list of glossing abbreviations, abbreviated as pl., pl, , or ), is one of the values of the grammatical number, grammatical category of number. The plural of a noun typically denotes a quantity greater than the default quantity represented by that noun. This default quantity is most commonly one (a form that represents this default quantity of one is said to be of ''singular'' number). Therefore, plurals most typically denote two or more of something, although they may also denote fractional, zero or negative amounts. An example of a plural is the English word ''boys'', which corresponds to the singular ''boy''. Words of other types, such as verbs, adjectives and pronouns, also frequently have distinct plural forms, which are used in agreement (linguistics), agreement with the number of their associated nouns. Some languages also have a dual (grammatical number), dual (denoting exactly two of something) or other systems of number categories. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cementum
Cementum is a specialized calcified substance covering the root of a tooth. The cementum is the part of the periodontium that attaches the teeth to the alveolar bone by anchoring the periodontal ligament. Structure The cells of cementum are the entrapped cementoblasts, the cementocytes. Each cementocyte lies in its lacuna, similar to the pattern noted in bone. These lacunae also have canaliculi or canals. Unlike those in bone, however, these canals in cementum do not contain nerves, nor do they radiate outward. Instead, the canals are oriented toward the periodontal ligament and contain cementocytic processes that exist to diffuse nutrients from the ligament because it is vascularized. After the apposition of cementum in layers, the cementoblasts that do not become entrapped in cementum line up along the cemental surface along the length of the outer covering of the periodontal ligament. These cementoblasts can form subsequent layers of cementum if the tooth is injured. Sh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dislocation (medicine)
A joint dislocation, also called luxation, occurs when there is an abnormal separation in the joint, where two or more bones meet. A partial dislocation is referred to as a subluxation. Dislocations are commonly caused by sudden trauma to the joint like during a car accident or fall. A joint dislocation can damage the surrounding ligaments, tendons, muscles, and nerves. Dislocations can occur in any major joint (shoulder, knees, hips) or minor joint (toes, fingers). The most common joint dislocation is a shoulder dislocation. The treatment for joint dislocation is usually by closed reduction, that is, skilled manipulation to return the bones to their normal position. Only trained medical professionals should perform reductions since the manipulation can cause injury to the surrounding soft tissue, nerves, or vascular structures. Signs and Symptoms The following symptoms are common with any type of dislocation. * Intense pain * Joint instability * Deformity of the joint area ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viscoelastic
In materials science and continuum mechanics, viscoelasticity is the property of materials that exhibit both Viscosity, viscous and Elasticity (physics), elastic characteristics when undergoing deformation (engineering), deformation. Viscous materials, like water, resist both shear flow and Strain (materials science), strain linearly with time when a Stress (physics), stress is applied. Elastic materials strain when stretched and immediately return to their original state once the stress is removed. Viscoelastic materials have elements of both of these properties and, as such, exhibit time-dependent strain. Whereas elasticity is usually the result of chemical bond, bond stretching along crystallographic planes in an ordered solid, viscosity is the result of the diffusion of atoms or molecules inside an amorphous material.Meyers and Chawla (1999): "Mechanical Behavior of Materials", 98-103. Background In the nineteenth century, physicists such as James Clerk Maxwell, Ludwig Boltzm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cruciate Ligament
Cruciate ligaments (also cruciform ligaments) are pairs of ligaments arranged like a letter X. They occur in several joints of the body, such as the knee joint, wrist joint and the atlanto-axial joint. In a fashion similar to the cords in a toy Jacob's ladder, the crossed ligaments stabilize the joint while allowing a very large range of motion. Knee Structure Cruciate ligaments occur in the knee of humans and other bipedal animals and the corresponding stifle of quadrupedal animals, and in the neck, fingers, and foot. * The cruciate ligaments of the knee are the anterior cruciate ligament (ACL) and the posterior cruciate ligament (PCL). These ligaments are two strong, rounded bands that extend from the head of the tibia to the intercondyloid notch of the femur. The ACL is lateral and the PCL is medial. They cross each other like the limbs of an X. They are named for their insertion into the tibia: the ACL attaches to the anterior aspect of the intercondylar area, ... [...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. As with most other joints, synovial joints achieve movement at the point of contact of the articulating bones. They originated 400 million years ago in the first jawed vertebrates. Structure Synovial joints contain the following structures: * Synovial cavity: all diarthroses have the characteristic space between the bones that is f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Articular Capsule
In anatomy, a joint capsule or articular capsule is an envelope surrounding a synovial joint. Each joint capsule has two parts: an outer fibrous layer or membrane, and an inner synovial layer or membrane. Membranes Each capsule consists of two layers or membranes: * an outer (fibrous membrane, ''fibrous stratum'') composed of avascular white fibrous tissue * an inner ('''', ''synovial stratum'') which is a secreting layer On the inside of the capsule, articular cartilage covers the end surfaces of the bones that articulate within ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muscle
Muscle is a soft tissue, one of the four basic types of animal tissue. There are three types of muscle tissue in vertebrates: skeletal muscle, cardiac muscle, and smooth muscle. Muscle tissue gives skeletal muscles the ability to muscle contraction, contract. Muscle tissue contains special Muscle contraction, contractile proteins called actin and myosin which interact to cause movement. Among many other muscle proteins, present are two regulatory proteins, troponin and tropomyosin. Muscle is formed during embryonic development, in a process known as myogenesis. Skeletal muscle tissue is striated consisting of elongated, multinucleate muscle cells called muscle fibers, and is responsible for movements of the body. Other tissues in skeletal muscle include tendons and perimysium. Smooth and cardiac muscle contract involuntarily, without conscious intervention. These muscle types may be activated both through the interaction of the central nervous system as well as by innervation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Joint
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. Joints play a vital role in the human body, contributing to movement, sta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dense Irregular Connective Tissue
Dense irregular connective tissue has fibers that are not arranged in parallel bundles as in dense regular connective tissue. Dense irregular connective tissue has less ground substance than loose connective tissue. Fibroblasts are the predominant cell type, scattered sparsely across the tissue. Function This type of connective tissue is found mostly in the reticular layer (or deep layer) of the dermis. It is also in the sclera and in the deeper skin layers. Due to high portions of collagenous fibers, dense irregular connective tissue provides strength, making the skin resistant to tearing by stretching forces from different directions. Dense irregular connective tissue also makes up submucosa of the digestive tract, lymph nodes, and some types of fascia. Other examples include periosteum The periosteum is a membrane that covers the outer surface of all bones, except at the articular surfaces (i.e. the parts within a joint space) of long bones. (At the joints of long b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Collagen
Collagen () is the main structural protein in the extracellular matrix of the connective tissues of many animals. It is the most abundant protein in mammals, making up 25% to 35% of protein content. Amino acids are bound together to form a triple helix of elongated fibril known as a collagen helix. It is mostly found in cartilage, bones, tendons, ligaments, and skin. Vitamin C is vital for collagen synthesis. Depending on the degree of biomineralization, mineralization, collagen tissues may be rigid (bone) or compliant (tendon) or have a gradient from rigid to compliant (cartilage). Collagen is also abundant in corneas, blood vessels, the Gut (anatomy), gut, intervertebral discs, and the dentin in teeth. In muscle tissue, it serves as a major component of the endomysium. Collagen constitutes 1% to 2% of muscle tissue and 6% by weight of skeletal muscle. The fibroblast is the most common cell creating collagen in animals. Gelatin, which is used in food and industry, is collagen t ... [...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 tendon A tendon or sinew is a tough band of fibrous connective tissue, dense fibrous connective tissue that connects skeletal muscle, muscle to bone. It sends the mechanical forces of muscle contraction to the skeletal system, while withstanding tensi ...s, which connec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
