|
Saddle Joint
A saddle joint (sellar joint, articulation by reciprocal reception) is a type of synovial joint in which the opposing surfaces are reciprocally concave and convex. It is found in the thumb, the thorax, the middle ear, and the heel. Structure In a saddle joint, one bone surface is concave while another is convex. This creates significant stability. Movements The movements of saddle joints are similar to those of the condyloid joint and include flexion, extension, adduction, abduction, and circumduction. However, axial rotation is not allowed. Saddle joints are said to be biaxial, allowing movement in the sagittal and frontal planes. Examples of saddle joints in the human body include the carpometacarpal joint of the thumb, the sternoclavicular joint of the thorax, the incudomalleolar joint of the middle ear, and the calcaneocuboid joint of the heel. Name The term "saddle" arises because the concave-convex bone interaction is compared to a horse rider riding a horse ... [...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 of joints 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 The pelvis (: pelves or pelvises) is the lower part of an Anatomy, anatomical Trunk (anatomy), trunk, between the human abdomen, abdomen and the thighs (sometimes also called pelvic region), together with its embedded skeleton (sometimes also c ...; and in the shoulder joint, where the rou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adduction
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] |
Equestrianism
Equestrianism (from Latin , , , 'horseman', 'horse'), commonly known as horse riding ( Commonwealth English) or horseback riding (American English), includes the disciplines of riding, driving, and vaulting. This broad description includes the use of horses for practical working purposes, transportation, recreational activities, artistic or cultural exercises, and competitive sport. Overview of equestrian activities Horses are trained and ridden for practical working purposes, such as in police work or for controlling herd animals on a ranch. They are also used in competitive sports including dressage, endurance riding, eventing, reining, show jumping, tent pegging, vaulting, polo, horse racing, driving, and rodeo (see additional equestrian sports listed later in this article for more examples). Some popular forms of competition are grouped together at horse shows where horses perform in a wide variety of disciplines. Horses (and other equids such as mules ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saddle
A saddle is a supportive structure for a rider of an animal, fastened to an animal's back by a girth. The most common type is equestrian. However, specialized saddles have been created for oxen, camels and other animals. It is not known precisely when riders first began to use some sort of padding or protection, but a blanket attached by some form of surcingle or girth was probably the first "saddle", followed later by more elaborate padded designs. The solid saddle tree was a later invention, and though early stirrup designs predated the invention of the solid tree, the paired stirrup, which attached to the tree, was the last element of the saddle to reach the basic form that is still used today. Present-day saddles come in a wide variety of styles, each designed for a specific equestrianism discipline, and require careful fit to both the rider and the horse. Proper saddle care can extend the useful life of a saddle, often for decades. The saddle was a crucial step in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcaneocuboid Joint
The calcaneocuboid joint is the joint between the calcaneus and the cuboid bone. Structure The calcaneocuboid joint is a type of saddle joint between the calcaneus and the cuboid bone. Ligaments There are five ligaments connecting the calcaneus and the cuboid bone, forming parts of the articular capsule: * the dorsal calcaneocuboid ligament. * part of the bifurcated ligament. * the long plantar ligament. * and the plantar calcaneocuboid ligament. Function The calcaneocuboid joint is conventionally described as among the least mobile joints in the human foot. The articular surfaces of the two bones are relatively flat with some irregular undulations, which seem to suggest movement limited to a single rotation and some translation. However, the cuboid rotates as much as 25° about an oblique axis during inversion- eversion in a movement that could be called involution. Clinical significance The calcaneocuboid joint may be affected by a calcaneal fracture. This may be a s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Incudomalleolar Joint
The incudomalleolar joint (also called incudomallear joint, or malleoincudal joint) or articulatio incudomallearis is a small saddle-type synovial joint between the malleus (hammer) and the incus (anvil). The joint's function is to transfer vibrations between the ossicles in the middle ear, which is perceived as sound. It may also play a role in protecting the inner ear during changes in static air pressure. Contrary to other synovial joints the movement is very limited. All of the ossicles move more or less as a unit, at least at low frequencies. When the eardrum In the anatomy of humans and various other tetrapods, the eardrum, also called the tympanic membrane or myringa, is a thin, cone-shaped membrane that separates the external ear from the middle ear. Its function is to transmit changes in pres ... is moved inward due to sound vibrations, transferred through the outer ear, it transmits to the handle or manubrium of the malleus which is connected to the ear drum. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sternoclavicular Joint
The sternoclavicular joint or sternoclavicular articulation is a Synovial joint, synovial Saddle joint, saddle joint between the sternum#Manubrium, manubrium of the sternum, and the clavicle bone, clavicle, and the first costal cartilage. The joint possesses a joint capsule, and an articular disk, articular disc, and is reinforced by multiple ligaments. Structure The joint is structurally classified as a Synovial joint, synovial saddle joint and functionally classed as a diarthrosis and multiaxial joint. It is composed of two portions separated by an articular disc of fibrocartilage. The joint is formed by the sternal end of the clavicle, the clavicular notch of the sternum, and (the superior surface of) the costal cartilage of the first rib. The articular surface of the clavicle is larger than that of the sternum, and is invested with a layer of cartilage, which is considerably thicker than that of the sternum. The joint receives arterial supply via branches of the internal tho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carpometacarpal Joint
The carpometacarpal (CMC) joints are five joints in the wrist that articulate the distal row of carpal bones and the proximal bases of the five metacarpal bones. The CMC joint of the thumb or the first CMC joint, also known as the trapeziometacarpal (TMC) joint, differs significantly from the other four CMC joints and is therefore described separately. Thumb The carpometacarpal joint of the thumb (''pollex''), also known as the first carpometacarpal joint, or the trapeziometacarpal joint (TMC) because it connects the trapezium to the first metacarpal bone, plays an irreplaceable role in the normal functioning of the thumb. The most important joint connecting the wrist to the metacarpus, osteoarthritis of the TMC is a severely disabling condition; it is up to twenty times more common among elderly women than in the average. Pronation-supination of the first metacarpal is especially important for the action of opposition. The movements of the first CMC are limited by the sha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biaxial Joint
In anatomy, a biaxial joint is a freely mobile joint that allows movement in two anatomical planes. An example of a biaxial joint is a metacarpophalangeal joint The metacarpophalangeal joints (MCP) are situated between the metacarpal bones and the proximal phalanges of the fingers. These joints are of the condyloid kind, formed by the reception of the rounded heads of the metacarpal bones into shallow ... of the hand. The joint allows for movement along one axis to produce bending or straightening of the finger, and movement along a second axis, which allows for spreading of the fingers away from each other and bringing them together. References Joints {{Anatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Axis (anatomy)
In anatomy, the axis (from Latin ''axis'', "axle") is the second cervical vertebra (C2) of the spine, immediately inferior to the atlas, upon which the head rests. The spinal cord passes through the axis. The defining feature of the axis is its strong bony protrusion known as the dens, which rises from the superior aspect of the bone. Structure The body is deeper in front or in the back and is prolonged downward anteriorly to overlap the upper and front part of the third vertebra. It presents a median longitudinal ridge in front, separating two lateral depressions for the attachment of the longus colli muscles. Dens The dens, also called the odontoid process, or the peg, is the most pronounced projecting feature of the axis. The dens exhibits a slight constriction where it joins the main body of the vertebra. The condition where the dens is separated from the body of the axis is called ''os odontoideum'' and may cause nerve and circulation compression syndrome. On its an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Circumduction (anatomy)
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] |
Abduction (kinesiology)
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] |
