Editing Carpal bones (section)

=== Movements ===
{{Main|Anatomical terms of motion#Special motions of the hands and feet}}
The hand is said to be in '''straight position''' when the third finger runs over the capitate bone and is in a straight line with the forearm. This should not be confused with the '''midposition''' of the hand which corresponds to an ulnar deviation of 12&nbsp;degrees. From the straight position two pairs of movements of the hand are possible: [[Abduction (kinesiology)|abduction]] (movement towards the radius, so called radial deviation or abduction) of 15&nbsp;degrees and [[adduction]] (movement towards the ulna, so called ulnar deviation or adduction) of 40&nbsp;degrees when the arm is in strict [[supination]] and slightly greater in strict [[pronation]].
<ref name="Platzer-132">Platzer 2004, p 132</ref>
[[Flexion]] (tilting towards the palm, so called palmar flexion) and [[Extension (kinesiology)|extension]] (tilting towards the back of the hand, so called dorsiflexion) is possible with a total range of 170&nbsp;degrees.
<ref name="Platzer-134">Platzer 2004, p 134</ref>

==== Radial abduction/ulnar adduction ====
[[File:Braus 1921 210.png|thumb|'''Left''': Ulnar adduction<br>'''Right''': Radial abduction]]
[[File:Braus 1921 214.png|thumb|'''Left''': Dorsiflexion<br>'''Right''': Palmar flexion]]
During '''radial abduction''' the scaphoid is tilted towards the palmar side which allows the trapezium and trapezoid to approach the radius. Because the trapezoid is rigidly attached to the second metacarpal bone to which also the flexor carpi radialis and extensor carpi radialis are attached, radial abduction effectively pulls this combined structure towards the radius. During radial abduction the pisiform traverses the greatest path of all carpal bones.
<ref name="Platzer-132" />
Radial abduction is produced by (in order of importance) [[Extensor carpi radialis longus muscle|extensor carpi radialis longus]], [[Abductor pollicis longus muscle|abductor pollicis longus]], [[Extensor pollicis longus muscle|extensor pollicis longus]], [[Flexor carpi radialis muscle|flexor carpi radialis]], and [[Flexor pollicis longus muscle|flexor pollicis longus]].
<ref name="Platzer-172">Platzer 2004, p 172</ref>

'''Ulnar adduction''' causes a tilting or dorsal shifting of the proximal row of carpal bones.<ref name="Platzer-132" />
It is produced by [[Extensor carpi ulnaris muscle|extensor carpi ulnaris]], [[Flexor carpi ulnaris muscle|flexor carpi ulnaris]], [[Extensor digitorum muscle|extensor digitorum]], and [[Extensor digiti minimi muscle|extensor digiti minimi]].<ref name="Platzer-172" />

Both radial abduction and ulnar adduction occurs around a dorsopalmar axis running through the head of the capitate bone.
<ref name="Platzer-132" />

==== Palmar flexion/dorsiflexion ====
During '''palmar flexion''' the proximal carpal bones are displaced towards the ''dorsal'' side and towards the ''palmar'' side during '''dorsiflexion'''. While flexion and extension consist of movements around a pair of transverse axes &mdash; passing through the lunate bone for the proximal row and through the capitate bone for the distal row &mdash; palmar flexion occurs mainly in the [[radiocarpal joint]] and dorsiflexion in the [[midcarpal joint]].
<ref name="Platzer-134" />

Dorsiflexion is produced by (in order of importance) [[Extensor digitorum muscle|extensor digitorum]], [[Extensor carpi radialis longus muscle|extensor carpi radialis longus]], [[Extensor carpi radialis brevis muscle|extensor carpi radialis brevis]], [[Extensor indicis muscle|extensor indicis]], [[Extensor pollicis longus muscle|extensor pollicis longus]], and [[Extensor digiti minimi muscle|extensor digiti minimi]]. Palmar flexion is produced by (in order of importance) [[Flexor digitorum superficialis muscle|flexor digitorum superficialis]], [[Flexor digitorum profundus muscle|flexor digitorum profundus]], [[Flexor carpi ulnaris muscle|flexor carpi ulnaris]], [[Flexor pollicis longus muscle|flexor pollicis longus]], [[Flexor carpi radialis muscle|flexor carpi radialis]], and [[Abductor pollicis longus muscle|abductor pollicis longus]].
<ref name="Platzer-172" />

==== Combined movements ====
Combined with movements in both the elbow and shoulder joints, '''intermediate''' or '''combined movements''' in the wrist approximate those of a [[ball-and-socket joint]] with some necessary restrictions, such as maximum palmar flexion blocking abduction.<ref name="Platzer-134" />

==== Accessory movements ====
[[Anatomical terms of location#Anterior and posterior 2|Anteroposterior]] gliding movements between adjacent carpal bones or along the midcarpal joint can be achieved by stabilizing individual bones while moving another (i.e. gripping the bone between the thumb and index finger).
<ref name="Palastanga-184">Palastanga 2006, p 184</ref>