Anatomical terms of motion
Encyclopedia
The movement of body structures is accomplished by the contraction of muscle
s. Muscles may move parts of the skeleton relatively to each other, or may move parts of internal organs relatively to each other. All such movements are classified by the directions in which the affected structures are moved. In human anatomy
, all descriptions of position and movement are based on the assumption that the body is its complete medial and abduction stage in anatomical position.
The prefix hyper- is sometimes added to emphasize movement beyond the normal position, such as in hyperflexion or hyperextension. Such movements can put significant stress on the joint
s involved. See: Medical terminology
All motions are considered to be a mixture of or a single contribution by the following types of movement.
Most terms of a motion have clear opposites, and as such, are treated below in pairs.
Some additional motions without clear opposites are as follows:
Muscle
Muscle is a contractile tissue of animals and is derived from the mesodermal layer of embryonic germ cells. Muscle cells contain contractile filaments that move past each other and change the size of the cell. They are classified as skeletal, cardiac, or smooth muscles. Their function is to...
s. Muscles may move parts of the skeleton relatively to each other, or may move parts of internal organs relatively to each other. All such movements are classified by the directions in which the affected structures are moved. In human anatomy
Human anatomy
Human anatomy is primarily the scientific study of the morphology of the human body. Anatomy is subdivided into gross anatomy and microscopic anatomy. Gross anatomy is the study of anatomical structures that can be seen by the naked eye...
, all descriptions of position and movement are based on the assumption that the body is its complete medial and abduction stage in anatomical position.
The prefix hyper- is sometimes added to emphasize movement beyond the normal position, such as in hyperflexion or hyperextension. Such movements can put significant stress on the joint
Joint
A joint is the location at which two or more bones make contact. They are constructed to allow movement and provide mechanical support, and are classified structurally and functionally.-Classification:...
s involved. See: Medical terminology
Medical terminology
Medical terminology is a vocabulary for accurately describing the human body and associated components, conditions, processes and process in a science-based manner. Some examples are: R.I.C.E., trapezius, and latissimus dorsi. It is to be used in the medical and nursing fields...
All motions are considered to be a mixture of or a single contribution by the following types of movement.
Most terms of a motion have clear opposites, and as such, are treated below in pairs.
General motion
| Adjusting angle between two parts | Flexion Flexion In anatomy, flexion is a position that is made possible by the joint angle decreasing. The skeletal and muscular systems work together to move the joint into a "flexed" position. For example the elbow is flexed when the hand is brought closer to the shoulder... – Bending movement that decreases the angle between two parts. Bending the elbow, or clenching a hand into a fist, are examples of flexion. When sitting down, the knees are flexed. Flexion of the hip or shoulder moves the limb forward (towards the anterior side of the body). Good examples of hip flexors are the rectus femoris, sartorius, iliacus, and psoas. Some knee flexors are the biceps femoris, semitendinosus, and semimembranosus. A couple elbow flexors are the brachialis, biceps brachii, and brachioradialis. |
Extension | Abduction Abduction (kinesiology) Abduction, in functional anatomy, is a movement which draws a limb away from the median plane of the body. It is thus opposed to adduction.-Upper limb:* of arm at shoulder ** Supraspinatus** Deltoid* of hand at wrist... – A motion that pulls a structure or part away from the midline of the body (or, in the case of fingers and toes, spreading the digits apart, away from the centerline of the hand or foot). Abduction of the wrist is called radial deviation. Raising the arms laterally, to the sides, is an example of abduction. A good example for the arm is the deltoid. Some leg abductors are the gluteus medius and the gluteus minimus. |
Adduction | Internal rotation Internal rotation In anatomy, internal rotation is rotation towards the center of the body.The muscles of internal rotation include:* of arm/humerus at shoulder** Deltoid muscle** Subscapularis** Teres major** Latissimus dorsi... (or medial rotation) of the shoulder or hip would point the toes or the flexed forearm inwards (towards the midline). The pectoralis major and subscapularis both medially rotate the humerus. The adductor longus and adductor brevis both medially rotate the thigh. |
External rotation | Elevation Elevation (kinesiology) Elevation, in kinesiology is the anatomical term of motion for movement in a superior direction.It is the opposite of depression.-Muscles:* elevation of the scapula at the shoulders Elevation, in kinesiology is the anatomical term of motion for movement in a superior direction.It is the opposite of... – Movement in a superior direction. The upper muscle fibers of the trapezius aid in elevating the apex of the shoulder. |
Depression Depression (kinesiology) Depression, in kinesiology, is the anatomical term of motion for movement in an inferior direction.It is the opposite of elevation.This term is often applied to the shoulders Depression, in kinesiology, is the anatomical term of motion for movement in an inferior direction.It is the opposite of... – Movement in an inferior direction, the opposite of elevation. Opposite to the upper fibers, the lower half of the trapezius aids in depressing the apex of the shoulder. |
Special motions of the hands and feet
| surfaces of the hands and feet | The palm (adj palmar) of the hand corresponds to the sole (adj plantar) of the foot. The adjective volar, used mainly in orthopaedics, is synonymous with palmar and plantar. | >- | Pronation Pronation In anatomy, pronation is a rotational movement of the forearm at the radioulnar joint, or of the foot at the subtalar and talocalcaneonavicular joints. For the forearm, when standing in the anatomical position, pronation will move the palm of the hand from an anterior-facing position to a... – A rotation of the forearm that moves the palm from an anterior-facing position to a posterior-facing position, or palm facing down. This is not medial rotation as this must be performed when the arm is half flexed. (See also Pronator quadratus Pronator quadratus Pronator quadratus is a square shaped muscle on the distal forearm that acts to pronate the hand.As it is on the anterior side of the arm, it is innervated by a branch of the median nerve, the anterior interosseous nerve... and Pronator teres muscle Pronator teres muscle The pronator teres is a muscle of the human body that, along with the pronator quadratus muscle, serves to pronate the forearm .-Structure:... .) |
Supination Supination Supination is a position of either the forearm or foot; in the forearm when the palm faces anteriorly, or faces up . Supination in the foot occurs when a person appears "bow-legged" with their weight supported primarily on the anterior of their feet.The hand is supine in the anatomical position... – The opposite of pronation, the rotation of the forearm so that the palm faces anteriorly, or palm facing up. The hand is supine (facing anteriorly) in the anatomical position. (See also Supinator muscle Supinator muscle In human anatomy, the supinator is a broad muscle in the posterior compartment of the forearm, curved around the upper third of the radius. Its function is to supinate the forearm.-Terminology:... .) >- | bending of the entire foot |
Dorsiflexion Dorsiflexion Dorsiflexion is the movement which decreases the angle between the dorsum of the foot and the leg, so that the toes are brought closer to the shin. The movement moving in opposite directions is called plantarflexion... – Extension of the entire foot superiorly, as if taking one's foot off an automobile pedal. |
Plantarflexion Plantarflexion Plantarflexion is the movement which increases the approximate 90 degree angle between the front part of the foot and the shin, as when depressing an automobile pedal... – Flexion of the entire foot inferiorly, as if pressing an automobile pedal. Occurs at ankle Ankle The ankle joint is formed where the foot and the leg meet. The ankle, or talocrural joint, is a synovial hinge joint that connects the distal ends of the tibia and fibula in the lower limb with the proximal end of the talus bone in the foot... . >- | movement of the sole of the foot |
Eversion Eversion (kinesiology) Eversion is the movement of the sole of the foot away from the median plane. It occurs at the subtalar joint.Peroneus longus and peroneus brevis evert. Both muscles are innervated by the superficial fibular nerve.... – the movement of the sole of the foot away from the median plane. |
Inversion Inversion (kinesiology) Inversion is the movement of the sole towards the median plane .Tibialis anterior and tibialis posterior invert. Some sources also state that the triceps surae and extensor hallucis longus invert.... – the movement of the sole towards the median plane (same as when an ankle is twisted). |
Other special motions
| anterior/posterior movement – general | Protrusion – The anterior movement of an object. This term is often applied to the jaw. | Retrusion – The opposite of protrusion, moving a part posteriorly. >- | anterior/posterior movement – shoulders |
Protraction Protraction Protraction is the anatomical term of motion for anterior movement of an anatomical part of the body forward . This can include the shoulders, jaw, pelvis, etc.It is the opposite of retraction.... – Anterior movement of the arms at the shoulders. |
Retraction Retraction (kinesiology) Retraction is the anatomical term of motion for posterior movement of the arms at the shoulders. It is the opposite of protraction. Major muscles involved include: * Rhomboid major muscle* Rhomboid minor muscle* Trapezius muscle-External links:* *... – Posterior movement of the arms at the shoulders. >- | motion within body (such as in blood vessel Blood vessel The blood vessels are the part of the circulatory system that transports blood throughout the body. There are three major types of blood vessels: the arteries, which carry the blood away from the heart; the capillaries, which enable the actual exchange of water and chemicals between the blood and... s or the digestive system) |
anterograde motion is in the normal direction of flow. (For example, passage of food from the mouth to the stomach.) | retrograde motion means reversed flow. (For example, gastric reflux Gerd In Norse mythology, Gerðr is a jötunn, goddess, and the wife of the god Freyr. Gerðr is attested in the Poetic Edda, compiled in the 13th century from earlier traditional sources; the Prose Edda and Heimskringla, written in the 13th century by Snorri Sturluson; and in the poetry of skalds... .) |
Some additional motions without clear opposites are as follows:
- Rotation – A motion that occurs when a part turns on its axis. The head rotates on the neck, as in shaking the head 'no'.
- Circumduction – The circular (or, more precisely, conicalCone (geometry)A cone is an n-dimensional geometric shape that tapers smoothly from a base to a point called the apex or vertex. Formally, it is the solid figure formed by the locus of all straight line segments that join the apex to the base...
) movement of a body part, such as a ball-and-socket joint or the eyeHuman eyeThe human eye is an organ which reacts to light for several purposes. As a conscious sense organ, the eye allows vision. Rod and cone cells in the retina allow conscious light perception and vision including color differentiation and the perception of depth...
. It consists of a combination of flexion, extension, adduction, and abduction. "Windmilling" the armArmIn human anatomy, the arm is the part of the upper limb between the shoulder and the elbow joints. In other animals, the term arm can also be used for analogous structures, such as one of the paired forelimbs of a four-legged animal or the arms of cephalopods...
s or rotating the handHandA hand is a prehensile, multi-fingered extremity located at the end of an arm or forelimb of primates such as humans, chimpanzees, monkeys, and lemurs...
from the wristWristIn human anatomy, the wrist is variously defined as 1) the carpus or carpal bones, the complex of eight bones forming the proximal skeletal segment of the hand;...
are examples of circumductive movement.
- Apposition – A motion involving a grasping of the thumb and fingers.
- Reposition – To release an object by spreading the fingers and thumb.
- Reciprocal motion of a joint – Alternating motion in opposing directions, such as the elbow alternating between flexion and extension.
External references
- White, T. D. & P. A. Folkens. Human Osteology. 1991. Academic Press, Inc. San Diego.