Adjusting Angle Between Two Parts
The action of bending or folding of a limb or joint. A movement that decreases the angle between two parts. Flexion of the hip or shoulder moves the limb forward (towards the anterior side of the body). Flexor muscles generally curl the body forward into the fetal position.
The action of moving a limb from a bent to a straight position (the opposite of flexion). A straightening movement that increases the angle between body parts. Extension of the hip or shoulder moves the limb backward (towards the posterior side of the body). When standing up, the knees are extended.
Adjusting Relation to Mid-line of Body
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). Abduction of the wrist is called radial deviation. Raising the arms laterally, to the sides, is an example of abduction.
A motion that pulls a structure or part towards the midline of the body, or towards the midline of a limb (the opposite of abduction). 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 called ulnar deviation.
Adductors and abductors oppose one another.
Rotating Body Parts
The action of rotating around an axis or center. In anatomical terms it means movement around the axis of a bone.
Internal Rotation (or medial rotation)
The rotation of the shoulder or hip would point the toes or the flexed forearm inwards (towards the midline).
External Rotation (or lateral rotation)
External rotation is the opposite of Internal Rotation. It would turn the toes or the flexed forearm outwards (away from the midline).
Movement in a superior (upward) direction.
Movement in an inferior (downward) direction, the opposite of elevation.
Special Motions of the Hands and Feet
Surfaces of the Hands and Feet
The palm of the hand corresponds to the sole of the foot. The adjective volar, used mainly in orthopedics, is synonymous with palmar and plantar. The dorsum (back) of the hand corresponds to the dorsum (top) of the foot.
Rotation of the Forearm
A rotation of the forearm that moves the palm from an anterior-facing position to a posterior-facing position (i.e. palm facing down).
The opposite of pronation, the rotation of the forearm so that the palm faces anteriorly (i.e. palm facing up).
Extension of the entire foot superiorly (i.e. flexing the ankle with the foot moving upwards).
Flexion of the entire foot inferiorly (i.e. flexing the ankle with the foot moving upwards).
The movement of the sole of the foot away from the median plane (outwards).
The movement of the sole of the foot towards the median plane (inwards).
Other Special Motions
Anterior and Posterior Movement – General
The anterior movement of an object.
The opposite of protrusion, moving a part posteriorly.
Anterior and Posterior Movement – Shoulders
Anterior movement of the arms at the shoulders (i.e. draw forward).
Posterior movement of the arms at the shoulders (i.e. draw back).
Motion within the Body
The circular (or, more precisely, conical) movement of a body part. It consists of a combination of flexion, extension, adduction, and abduction.
A motion involving a grasping of the thumb and fingers.
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.