Anatomical terms of motion

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Muscles drive many movements of the human body, both voluntary and involuntary. They move organs, members, and the whole body in specific ways described by anatomical terminology. The terminology describes movement according to its direction. Anatomists use a unified set of terms to describe most of the movements, although other, more specialized terms are necessary for describing movements such as those of the hands, feet, and eyes.

The anatomical positions of the joints are the basis for description of most obvious skeletal movements, but there also are classes of movement, both voluntary and involuntary, in which joints and even skeletal elements play little part, such as movements of eyes, viscera and lips.

Classifications of motion[edit]

Motions are classified after the anatomical planes they occur in,[1] although movement is more often than not a combination of different motions occurring simultaneously in several planes.[2] Additionally, motion may be divided into gross motion, affecting the large joints (such as legs, arms, and torso), and fine movements, which describe those made by the fingers, toes, feet or wrist. The study of movement is known as Kinesiology, and a categoric list of movements of the human body and the muscles involved can be found at List of movements of the human body.

Motions can be split into three categories as per how they engage different joints of the body:

Apart from this motions can also be divided into:[2]

Abnormal motion[edit]

The prefix hyper- is sometimes added to describe movement beyond the normal limits to a limb's or organ's motion, such as in hyperflexion or hyperextension. Such movements are variously important; they may be used in surgery, such as in temporarily dislocating joints for surgical procedures, and also may be important in that they may seriously stress the joints involved. Such prefixes are common in Medical terminology. If a part of the body such as a joint is overstretched or "bent backwards" because of exaggerated extension motion, then one speaks of a hyperextension (as with the knee). This puts increased stress on the ligaments of the joint, and need not always be a voluntary movement, but may occur as part of accidents, falls, or other causes of trauma. Hyperextension is also sometimes defined as normal movement into the space posterior to the anatomical position.[3]

General motion[edit]

Body Movements I.jpg

These are general terms that can be use to describe most movements the body makes. Most terms have a clear opposite, and so are treated in pairs.

Flexion and extension[edit]

Flexion and extension describe movements that affect the angle between two parts of the body. These terms come from the Latin words of the same meaning.[a]

Flexion describes a bending movement that decreases the angle between two parts.[5] For example, bending the elbow, or clenching a hand into a fist, are examples of flexion. When sitting down, the knees are flexed. Flexion of the shoulder or hip refers to movement of the arm of leg forward. [6]

Extension is the opposite of flexion, describing a straightening movement that increases the angle between body parts.[7] When standing up, the knees are extended. Extension of the hip or shoulder moves the limb backward. [6] In a conventional high five, the fingers are fully extended.

Abduction and adduction[edit]

Abduction and adduction refer to motions that move a structure away from or towards the centre of the body.[8] These terms come from the Latin words of the same meaning.[b]

Abduction refers to 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 also called radial deviation. [8] Raising the arms laterally, such as when tightrope-walking, is an example of abduction at the shoulder. [6]

Adduction refers to a motion that pulls a structure or part toward the midline of the body, or towards the midline of a limb. Dropping the arms to the sides, or bringing the knees together, are examples of adduction. In the case of the fingers or toes, adduction is closing the digits together. Adduction of the wrist is also called ulnar deviation. Bringing the arms closer to the body is an example of adduction at the shoulder. [8]

Elevation and depression[edit]

The terms elevation and depression refer to movement above and below the horizontal. They derive from the Latin terms of the same meaning [c]

Elevation refers to movement in a superior direction.[11] For example, raising the arm upwards is elevating the arm.

Depression refers to movement in an inferior direction, the opposite of elevation.[12] For example, depressing the eyelid will close the eyes.


Rotation of body parts is referred to as internal or external, referring to rotation towards or away from the center of the body.[13]

Internal rotation (or medial rotation) refers to rotation towards the axis of the body. [13] For example, a roman salute, in which the arm is placed against the chest, is an example of internal rotation.

External rotation (or lateral rotation) refers to rotation away from the center of the body. [13] For example, the legs are externally rotated in the lotus posture of yoga


Special motion[edit]

Special motions of the hands and feet[edit]

Flexion and extension of the foot[edit]

Dorsiflexion and plantarflexion refers to extension (dorsiflexion) or flexion (plantarflexion) of the foot at the ankle. These terms refer to flexion between the foot and the body's dorsal surface, considered the front of the leg, and flexion between the foot and the body's plantar surface, considered the back of the leg.[17]

Dorsiflexion where the toes are brought closer to the shin. This flexion decreases the angle between the dorsum of the foot and the leg. [18] An example includes the position of the foot when walking on the heels.

Plantarflexion is the movement which decreases the angle between the sole of the foot and the back of the leg. For example, when depressing an car pedal or standing on the tiptoes.

Flexion and extension of the hand[edit]

Palmarflexion and dorsiflexion refer to movement of the flexion (palmarflexion) or extension (dorsiflexion) of the hand at the wrist.[19] These terms refer to flexion between the hand and the body's dorsal surface, considered the front of the arm, and flexion between the hand and the body's plantar surface, considered the back of the arm.[17]

Palmarflexion refers to decreasing the angle between the palm and the forearm. [19]

Dorsiflexion refers to extension at the wrist joint. This brings the hand closer to the dorsum of the body. [19] For example, prayer is often conducted with the hands dorsiflexed.

Pronation and supination[edit]

Pronation and supination refer to rotation of the forearm or foot so that in the anatomical position the palm or sole is facing anteriorly (supination) or posteriorly (pronation).[20]

Pronation at the forearm is a rotational movement where the hand and upper arm are turned inwards. Pronation of the foot refers to turning of the foot outwards, so that weight is borne on the medial part of the foot. [21]

Supination of the forearm occurs when the forearm or palm are rotated outwards. Supination of the foot refers to turning of the sole of the foot inwards.[22]

Inversion and eversion[edit]

Inversion and eversion refer to movements that tilt the sole of the foot away from (eversion) or towards (inversion) the midline of the body.[23]

Eversion is the movement of the sole of the foot away from the median plane.[24] Inversion is the movement of the sole towards the median plane (as when an ankle is twisted).[18]

Special motions of the eyes[edit]

Unique terminology is also used to describe the eye. For example:

Special motions of the jaw and teeth[edit]

Special motion of the fingers and thumb[edit]


Such terms include:


  1. ^ "to stretch out" (Latin: extendere), "to bend" Latin: flectere)[4]
  2. ^ "to bring in" (Latin: adductere), "to lead away" Latin: abducere[9]
  3. ^ "press down" (Latin: deprimere), "to raise" (Latin: elevare)[10]


  1. ^ a b Marieb 2010, pp. 212.
  2. ^ a b Lippert 2011, pp. 6-7.
  3. ^ Seeley 1998, pp. 229.
  4. ^ OED 1989, "Flexion, Extension".
  5. ^ OED 1989, "Flexion".
  6. ^ a b c Cook 2012, pp. 180-193.
  7. ^ OED 1989, "Extension".
  8. ^ a b c Swartz 2010, pp. 590–591.
  9. ^ OED 1989, "Adduction, Abduction, Abduct".
  10. ^ OED 1989.
  11. ^ OED 1989, "elevation".
  12. ^ OED 1989, "depression".
  13. ^ a b c Swartz 2010, pp. 590-1.
  14. ^ OED 1989, "Anterograde, Retrograde".
  15. ^ Saladin 2010, pp. 300.
  16. ^ Taber 2001, "reduction".
  17. ^ a b OED & 1989 "plantarflexion, dorsiflexion".
  18. ^ a b Kyung 2005, pp. 123.
  19. ^ a b c Swartz 2010, pp. 591-3.
  20. ^ Swartz 2010, pp. 591–592.
  21. ^ OED 1989, "pronation".
  22. ^ OED 1989, "supination".
  23. ^ Swartz 2010, pp. 591.
  24. ^ Kyung 2005, pp. 108.
  25. ^ Kanski, JJ. Clinical Ophthalmology: A Systematic Approach. Boston:Butterworth-Heinemann;1989.
  26. ^ Taber 2001, "Torsion".
  27. ^ Taber 2001, "occlusion".
  28. ^ Taber 2001, "protrusion, retrusion".
  29. ^ Taber 2001, "opposition".
  30. ^ OED 1989, "resposition".
  31. ^ OED 1989, "protraction, retraction".
  32. ^ Taber 2001, "reciprocation".
  33. ^ Houglum 2012, pp. 333.
  34. ^ OED 1989, "Nutation".


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