[Jeff]

I thought that TGM students may enjoy understanding the anatomy of wrist movements so I produced the following image.



There are 8 wrist (carpal) bones.

Only two planar movements are possible at the wrist joint in two opposite planes - hinging (what HK calls bending/flattening) and cocking.

Cocking upwards causes radial deviation of the wrist - see left upper photo. It occurs mainly as a sliding action at the radio-carpal joint between the end of the radius and the scaphoid bone. Cocking downwards causes ulnar deviation of the wrist (see right upper photo) and occurs mainly at the articulation between the radius and the two proximal carpal bones (scaphoid and lunate).

Hinging forwards (palmar flexion) produces a palmar-flexed hand, and occurs at two articulatory levels - a certain amount of sliding between the radius and lunate bone, and a certain amount of inter-carpal joint sliding between the lunate and capitate wrist bones. Hinging backwards (dorsiflexion) produces a dorsiflexed hand (what TGM calls a bent wrist) and occurs partly at the level of the radiocarpal articulation (between the radius and lunate bone) and partly at the level of the intercarpal articulation between the lunate and capitate wrist bones.

Pronation and supination of the hand are not wrist movements and usually occur due to rotation of the radius bone over the ulna bone in the forearm, but the rotary movement can also occur at the level of the shoulder socket joint.

Jeff.