Question

Highlight the movements at the; Radio Carpal Joint, Intercarpal joints, Carpometacarpal joint and Mid carpal joints. High light the muscles involved in bringing about the movements listed above. Make reference to their proximal and distal attachment sites (origins and insertion sites)

Answer 1

Radio carpal joint:- This is the complex joint that marks transition between forearm and the hand. It is the joint where radius(proximal) of forearm meets the first row of carpel bones(distal) in the lower hand.

The muscles involved in movements of wrist arm:- *flexation produced by flexor carpi ulnaris and flexor carpi radialis with the assistance of flexor digitorium superficialis. Extension produced by extensor carpi radialis longus and brevis and extensor carpi ulnaris with the assistance of extensor digitorium.

Intercarpal joints:- These are the carpal bones of wrist are sub-divided into three sets of joints(articulations). Those of the proximal row of carpal bones, distal row of carpal bones and those of the two each other. The joints of the proximal row are arthroidal joints(scaphoid, lunate and the traquetrum) connected to the distal row(dorsal, volar and interosseous ligaments).

The movements of intercarpal joints includes:- * Carpal bones rotates on a transverse axis drawn between the tips of the styloid processes of the radius and ulna. A certain amount of adduction(or lunar flexation) and abduction( or lunar flexation) also permitted. Thus muscles involved are flexor pollicis longus and brevis assisted by the opponens pollicis and adductor pollicis.

Carpometacarpal joints:- These are the five joints in the wrist that articulate with the distal row of carpal bones and proximal basis of five metacarpal bones. The first carpometacarpal joint with thumb is called trapeziometacarpal joint.

The movements permitted are flexation and extension in the plane of the palm. Adduction and abduction in the right angles to the palm, circumduction and opposition. Flexation(flexor pollicis longus and bravis assisted by the opponens pollicis and adductor pollicis. Extension(abductor pollicis longus, extensores pollicis longus and brevis).

Mid carpal joints:- These joints ariculates with proximal row of carpal bones and distal row of carpal bones. At lateral portion of joint, scaphoid articulates with trapezium and trapezoid. Centrally, scaphoid and lunate articulate with the capitate.

The movements include flexation, extension, abduction and adduction. Thenar muscles, hypothenar muscles, palmaris brevis and intermediate muscles are involved in the movent of mid carpal joints.