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55-497: 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

110-464: A pain compliance method to force a person to take a certain action, such as allowing a police officer to take him into custody. These are general terms that can be used to describe most movements the body makes. Most terms have a clear opposite, and so are treated in pairs. Flexion and extension are movements that affect the angle between two parts of the body. These terms come from the Latin words with

165-460: A star jump or doing a split , the legs are abducted at the hip. Adduction is a motion that pulls a structure or part towards the midline of the body, or towards the midline of a limb, carried out by one or more adductor muscles. In the case of fingers and toes, it is bringing the digits together, towards the centerline of the hand or foot. Dropping the arms to the sides, and bringing the knees together, are examples of adduction. Adduction of

220-516: A body or an object is not equal to zero, the body will have an acceleration a {\displaystyle a} that is in the same direction as the resultant force. Classical mechanics is used for describing the motion of macroscopic objects moving at speeds significantly slower than the speed of light, from projectiles to parts of machinery , as well as astronomical objects , such as spacecraft , planets , stars , and galaxies . It produces very accurate results within these domains and

275-462: A part of the body such as a joint is overstretched or "bent backwards" because of exaggerated extension motion, then it can be described as hyperextended . Hyperextension increases the stress on the ligaments of a joint, and is not always because of a voluntary movement. It may be a result of accidents, falls, or other causes of trauma. It may also be used in surgery, such as in temporarily dislocating joints for surgical procedures. Or it may be used as

330-566: Is rotating around its dense Galactic Center , thus the Sun is moving in a circle within the galaxy 's gravity . Away from the central bulge, or outer rim, the typical stellar velocity is between 210 and 240 kilometres per second (470,000 and 540,000 mph). All planets and their moons move with the Sun. Thus, the Solar System is in motion. The Earth is rotating or spinning around its axis . This

385-404: Is special relativity . Efforts to incorporate gravity into relativistic mechanics were made by W. K. Clifford and Albert Einstein . The development used differential geometry to describe a curved universe with gravity; the study is called general relativity . Quantum mechanics is a set of principles describing physical reality at the atomic level of matter ( molecules and atoms ) and

440-410: Is a motion that pulls a structure or part away from the midline of the body, carried out by one or more abductor muscles. In the case of fingers and toes, it is spreading the digits apart, away from the centerline of the hand or foot. For example, raising the arms up, such as when tightrope -walking, is an example of abduction at the shoulder . When the legs are splayed at the hip, such as when doing

495-415: Is against the chest, the neck is flexed, and the trunk is flexed when a person leans forward. Flexion of the shoulder or hip is movement of the arm or leg forward. Extension is the opposite of flexion, a straightening movement that increases the angle between body parts. For example, when standing up, the knees are extended. When a joint can move forward and backward, such as the neck and trunk, extension

550-400: Is also the speed of all massless particles and associated fields in a vacuum, and it is the upper limit on the speed at which energy, matter, information or causation can travel. The speed of light in vacuum is thus the upper limit for speed for all physical systems. In addition, the speed of light is an invariant quantity: it has the same value, irrespective of the position or speed of

605-500: Is described through two related sets of laws of mechanics. Classical mechanics for super atomic (larger than an atom) objects (such as cars , projectiles , planets , cells , and humans ) and quantum mechanics for atomic and sub-atomic objects (such as helium , protons , and electrons ). Historically, Newton and Euler formulated three laws of classical mechanics : If the resultant force F → {\displaystyle {\vec {F}}} acting on

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660-405: Is evidenced by day and night , at the equator the earth has an eastward velocity of 0.4651 kilometres per second (1,040 mph). The Earth is also orbiting around the Sun in an orbital revolution . A complete orbit around the Sun takes one year , or about 365 days; it averages a speed of about 30 kilometres per second (67,000 mph). The Theory of Plate tectonics tells us that

715-483: Is movement in a superior direction. For example, shrugging is an example of elevation of the scapula. Depression is movement in an inferior direction, the opposite of elevation. Rotation of body parts may be internal or external, that is, towards or away from the center of the body. Internal rotation ( medial rotation or intorsion ) is rotation towards the axis of the body, carried out by internal rotators . External rotation ( lateral rotation or extorsion )

770-403: Is movement in the posterior direction. Extension of the hip or shoulder moves the arm or leg backward. Even for other upper extremity joints – elbow and wrist, backward movement results in extension. The knee, ankle, and wrist are exceptions, where the distal end has to move in the anterior direction for it to be called extension. For the toes , flexion is curling them downward whereas extension

825-523: Is moving through space and many astronomers believe the velocity of this motion to be approximately 600 kilometres per second (1,340,000 mph) relative to the observed locations of other nearby galaxies. Another reference frame is provided by the Cosmic microwave background . This frame of reference indicates that the Milky Way is moving at around 582 kilometres per second (1,300,000 mph). The Milky Way

880-618: Is not in motion relative to a given frame of reference, it is said to be at rest , motionless , immobile , stationary , or to have a constant or time-invariant position with reference to its surroundings. Modern physics holds that, as there is no absolute frame of reference, Newton 's concept of absolute motion cannot be determined. Everything in the universe can be considered to be in motion. Motion applies to various physical systems: objects, bodies, matter particles , matter fields, radiation , radiation fields, radiation particles, curvature , and space-time . One can also speak of

935-410: Is often calculated at long distances; oftentimes calculations fail to account for the fact that the speed of light is finite. When measuring the movement of distant objects across the sky, there is a large time delay between what has been observed and what has occurred, due to the large distance the light from the distant object has to travel to reach us. The error in the above naive calculation comes from

990-493: Is one of the oldest and largest scientific descriptions in science , engineering , and technology . Classical mechanics is fundamentally based on Newton's laws of motion . These laws describe the relationship between the forces acting on a body and the motion of that body. They were first compiled by Sir Isaac Newton in his work Philosophiæ Naturalis Principia Mathematica , which was first published on July 5, 1687. Newton's three laws are: Newton's three laws of motion were

1045-400: Is rotation away from the center of the body, carried out by external rotators . Internal and external rotators make up the rotator cuff , a group of muscles that help to stabilize the shoulder joint . Dorsiflexion and plantar flexion refer to extension or flexion of the foot at the ankle. These terms refer to flexion in direction of the "back" of the foot, which is the upper surface of

1100-470: Is stretching, like a rubber band . This motion is the most obscure as it is not physical motion, but rather a change in the very nature of the universe. The primary source of verification of this expansion was provided by Edwin Hubble who demonstrated that all galaxies and distant astronomical objects were moving away from Earth, known as Hubble's law , predicted by a universal expansion. The Milky Way Galaxy

1155-422: Is then interpreted as rapidity , the hyperbolic angle φ {\displaystyle \varphi } for which the hyperbolic tangent function tanh ⁡ φ = v ÷ c {\displaystyle \tanh \varphi =v\div c} . Acceleration , the change of velocity over time, then changes rapidity according to Lorentz transformations . This part of mechanics

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1210-497: Is uncurling them or raising them. Abduction is the motion of a structure away from the midline while adduction is motion towards the center of the body. The center of the body is defined as the midsagittal or longitudinal plane. These terms come from Latin words with similar meanings, ab- being the Latin prefix indicating ' away ' , ad- indicating ' toward ' , and ducere meaning ' to draw or pull ' . Abduction

1265-587: The 2019 revision of the SI , also termed the New SI . Some motion appears to an observer to exceed the speed of light. Bursts of energy moving out along the relativistic jets emitted from these objects can have a proper motion that appears greater than the speed of light. All of these sources are thought to contain a black hole , responsible for the ejection of mass at high velocities. Light echoes can also produce apparent superluminal motion. This occurs owing to how motion

1320-466: The Heisenberg uncertainty principle , the complete state of a subatomic particle, such as its location and velocity, cannot be simultaneously determined. In addition to describing the motion of atomic level phenomena, quantum mechanics is useful in understanding some large-scale phenomena such as superfluidity , superconductivity , and biological systems , including the function of smell receptors and

1375-465: The Latin word sagitta , meaning "arrow". An image of an arrow piercing a body and passing from front (anterior) to back (posterior) on a parabolic trajectory with the upright bow that shot it would be one way to demonstrate the derivation of the term. Another explanation would involve the notching of the sagittal suture posteriorly by the lambdoidal suture —similar to feathers on an arrow. The Oxford English Dictionary indicates that sagittal in

1430-578: The continents are drifting on convection currents within the mantle , causing them to move across the surface of the planet at the slow speed of approximately 2.54 centimetres (1 in) per year. However, the velocities of plates range widely. The fastest-moving plates are the oceanic plates, with the Cocos Plate advancing at a rate of 75 millimetres (3.0 in) per year and the Pacific Plate moving 52–69 millimetres (2.0–2.7 in) per year. At

1485-433: The leg . For example, when walking on the heels the ankle is described as being in dorsiflexion. Similarly, dorsiflexion helps in assuming a deep squat position. Plantar flexion or plantarflexion is the movement which decreases the angle between the sole of the foot and the back of the leg; for example, the movement when depressing a car pedal or standing on tiptoes. Palmarflexion and dorsiflexion refer to movement of

1540-468: The longitudinal plane ) is an anatomical plane that divides the body into right and left sections. It is perpendicular to the transverse and coronal planes. The plane may be in the center of the body and divide it into two equal parts ( mid-sagittal ), or away from the midline and divide it into unequal parts (para-sagittal). The term sagittal was coined by Gerard of Cremona . Examples of sagittal planes include: The term sagittal derives from

1595-499: The smooth muscles of hollow internal organs are moving. The most familiar would be the occurrence of peristalsis , which is where digested food is forced throughout the digestive tract . Though different foods travel through the body at different rates, an average speed through the human small intestine is 3.48 kilometres per hour (2.16 mph). The human lymphatic system is also constantly causing movements of excess fluids , lipids , and immune system related products around

1650-530: The structures of protein . Humans, like all known things in the universe, are in constant motion; however, aside from obvious movements of the various external body parts and locomotion , humans are in motion in a variety of ways that are more difficult to perceive . Many of these "imperceptible motions" are only perceivable with the help of special tools and careful observation. The larger scales of imperceptible motions are difficult for humans to perceive for two reasons: Newton's laws of motion (particularly

1705-463: The subatomic particles ( electrons , protons , neutrons , and even smaller elementary particles such as quarks ). These descriptions include the simultaneous wave-like and particle-like behavior of both matter and radiation energy as described in the wave–particle duality . In classical mechanics, accurate measurements and predictions of the state of objects can be calculated, such as location and velocity . In quantum mechanics, due to

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1760-430: The temperature is above absolute zero . Thus the molecules and atoms that make up the human body are vibrating, colliding, and moving. This motion can be detected as temperature; higher temperatures, which represent greater kinetic energy in the particles, feel warm to humans who sense the thermal energy transferring from the object being touched to their nerves. Similarly, when lower temperature objects are touched,

1815-420: The wrist is also known as ulnar deviation which moves the hand towards the ulnar styloid (or, towards the little finger ). Abduction of the wrist is also called radial deviation which moves the hand moving towards the radial styloid (or, towards the thumb ). Elevation and depression are movements above and below the horizontal. The words derive from the Latin terms with similar meanings. Elevation

1870-407: The body. The lymph fluid has been found to move through a lymph capillary of the skin at approximately 0.0000097 m/s. The cells of the human body have many structures and organelles that move throughout them. Cytoplasmic streaming is a way in which cells move molecular substances throughout the cytoplasm , various motor proteins work as molecular motors within a cell and move along

1925-435: The bounds of the electron cloud. Inside the atomic nucleus , the protons and neutrons are also probably moving around due to the electrical repulsion of the protons and the presence of angular momentum of both particles. Light moves at a speed of 299,792,458 m/s, or 299,792.458 kilometres per second (186,282.397 mi/s), in a vacuum. The speed of light in vacuum (or c {\displaystyle c} )

1980-411: The electron cloud in strict paths the same way planets orbit the Sun, then electrons would be required to do so at speeds that would far exceed the speed of light. However, there is no reason that one must confine oneself to this strict conceptualization (that electrons move in paths the same way macroscopic objects do), rather one can conceptualize electrons to be 'particles' that capriciously exist within

2035-509: The fact that when an object has a component of velocity directed towards the Earth, as the object moves closer to the Earth that time delay becomes smaller. This means that the apparent speed as calculated above is greater than the actual speed. Correspondingly, if the object is moving away from the Earth, the above calculation underestimates the actual speed. Sagittal plane The sagittal plane ( / ˈ s æ dʒ ɪ t əl / ; also known as

2090-424: The first to accurately provide a mathematical model for understanding orbiting bodies in outer space . This explanation unified the motion of celestial bodies and the motion of objects on Earth. Modern kinematics developed with study of electromagnetism and refers all velocities v {\displaystyle v} to their ratio to speed of light c {\displaystyle c} . Velocity

2145-409: The flexion (palmarflexion) or extension (dorsiflexion) of the hand at the wrist. These terms refer to flexion between the hand and the body's dorsal surface, which in anatomical position is considered the back of the arm; and flexion between the hand and the body's palmar surface, which in anatomical position is considered the anterior side of the arm. The direction of terms are opposite to those in

2200-416: The foot because of embryological rotation of the limbs in opposite directions. Palmarflexion is flexion of the wrist towards the palm and ventral side of forearm . Dorsiflexion is hyperextension of the wrist joint, towards the dorsal side of forearm. Pronation and supination refer generally to the prone (facing down) or supine (facing up) positions. In the extremities, they are

2255-408: The foot when standing, and flexion in direction of the sole of the foot. These terms are used to resolve confusion, as technically extension of the joint is dorsiflexion, which could be considered counter-intuitive as the motion reduces the angle between the foot and the leg. Dorsiflexion is where the toes are brought closer to the shin . This decreases the angle between the dorsum of the foot and

Anatomical terms of motion - Misplaced Pages Continue

2310-459: 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

2365-445: The horizontal plane. Many anatomical terms derive from Latin terms with the same meaning. Motions are classified after the anatomical planes they occur in, although movement is more often than not a combination of different motions occurring simultaneously in several planes. Motions can be split into categories relating to the nature of the joints involved: Apart from this motions can also be divided into: The study of movement in

2420-409: The human body is known as kinesiology . A categoric list of movements and the muscles involved can be found at list of movements of the human body . The prefix hyper- is sometimes added to describe movement beyond the normal limits, such as in hypermobility , hyperflexion or hyperextension . The range of motion describes the total range of motion that a joint is able to do. For example, if

2475-414: The motion of images, shapes, and boundaries. In general, the term motion signifies a continuous change in the position or configuration of a physical system in space. For example, one can talk about the motion of a wave or the motion of a quantum particle, where the configuration consists of the probabilities of the wave or particle occupying specific positions. In physics, the motion of massive bodies

2530-408: The observer. This property makes the speed of light c a natural measurement unit for speed and a fundamental constant of nature. In 2019, the speed of light was redefined alongside all seven SI base units using what it calls "the explicit-constant formulation", where each "unit is defined indirectly by specifying explicitly an exact value for a well-recognized fundamental constant", as was done for

2585-566: The other extreme, the slowest-moving plate is the Eurasian Plate , progressing at a typical rate of about 21 millimetres (0.83 in) per year. The human heart is regularly contracting to move blood throughout the body. Through larger veins and arteries in the body, blood has been found to travel at approximately 0.33 m/s. Though considerable variation exists, and peak flows in the venae cavae have been found between 0.1 and 0.45 metres per second (0.33 and 1.48 ft/s). additionally,

2640-408: The rotation of the forearm or foot so that in the standard anatomical position the palm or sole is facing anteriorly when in supination and posteriorly when in pronation. As an example, when a person is typing on a computer keyboard, their hands are pronated; when washing their face, they are supinated. Pronation at the forearm is a rotational movement where the hand and upper arm are turned so

2695-400: The same meaning. Flexion is a bending movement that decreases the angle between a segment and its proximal segment. For example, bending the elbow , or clenching a hand into a fist, are examples of flexion. When a person is sitting down, the knees are flexed. When a joint can move forward and backward, such as the neck and trunk, flexion is movement in the anterior direction. When the chin

2750-423: The senses perceive the transfer of heat away from the body as a feeling of cold. Within the standard atomic orbital model , electrons exist in a region around the nucleus of each atom. This region is called the electron cloud . According to Bohr's model of the atom, electrons have a high velocity , and the larger the nucleus they are orbiting the faster they would need to move. If electrons were to move about

2805-444: The sole of the foot away from (eversion) or towards (inversion) the midline of the body. Eversion is the movement of the sole of the foot away from the median plane . Inversion is the movement of the sole towards the median plane . For example, inversion describes the motion when an ankle is twisted . Unique terminology is also used to describe the eye. For example: Other terms include: Motion If an object

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2860-405: The speed of light. A new, but completely equivalent, wording of the metre's definition was proposed: "The metre, symbol m, is the unit of length; its magnitude is set by fixing the numerical value of the speed of light in vacuum to be equal to exactly 299 792 458 when it is expressed in the SI unit m s ." This implicit change to the speed of light was one of the changes that was incorporated in

2915-440: The surface of various cellular substrates such as microtubules , and motor proteins are typically powered by the hydrolysis of adenosine triphosphate (ATP), and convert chemical energy into mechanical work. Vesicles propelled by motor proteins have been found to have a velocity of approximately 0.00000152 m/s. According to the laws of thermodynamics , all particles of matter are in constant random motion as long as

2970-404: The third), which prevents the feeling of motion on a mass to which the observer is connected, and the lack of an obvious frame of reference that would allow individuals to easily see that they are moving. The smaller scales of these motions are too small to be detected conventionally with human senses . Spacetime (the fabric of the universe) is expanding , meaning everything in the universe

3025-462: The thumbs point towards the body. When the forearm and hand are supinated, the thumbs point away from the body. Pronation of the foot is turning of the sole outwards, so that weight is borne on the medial part of the foot. Supination of the forearm occurs when the forearm or palm are rotated outwards. Supination of the foot is turning of the sole of the foot inwards, shifting weight to the lateral edge. Inversion and eversion are movements that tilt

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