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.


Radial abduction is produced by (in order of importance) extensor carpi radialis longus, abductor pollicis longus, extensor pollicis longus, flexor carpi radialis, and flexor pollicis longus.

Ulnar adduction causes a tilting or dorsal shifting of the proximal row of carpal bones.

It is produced by extensor carpi ulnaris, flexor carpi ulnaris, extensor digitorum, and extensor digiti minimi.

Both radial abduction and ulnar adduction occurs around a dorsopalmar axis running through the head of the capitate bone.
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.

Radial abduction is produced by (in order of importance) extensor carpi radialis longus, abductor pollicis longus, extensor pollicis longus, flexor carpi radialis, and flexor pollicis longus.
Ulnar adduction causes a tilting or dorsal shifting of the proximal row of carpal bones.
It is produced by extensor carpi ulnaris, flexor carpi ulnaris, extensor digitorum, and extensor digiti minimi.
Both radial abduction and ulnar adduction occurs around a dorsopalmar axis running through the head of the capitate bone.
Carpal bones