2/O TJie Fore -anti, Wrist, and Hand 



the fact that the creases themselves are not landmarks to the joints, 

 but that the line of the joints lies halfway between the palmar creases 

 and the creases at the roots of the ringers, that is along the middle line 

 of the tranverse fold. 



The deep fascia offers a strong investment to the superficial 

 muscles of the fore-arm, and, dipping between them, supplies inter- 

 muscular septa from which they take additional origin. It receives 

 important accessory fibres from the insertions of the biceps and 

 triceps. It is attached along the posterior the subcutaneous border 

 of the ulna, and above it is continuous with the deep fascia of the arm; 

 below it passes to the front and back of the hand, being thickened to 

 form the annular ligaments. 



The posterior annular ligament is firmly connected by transverse 

 fibres with the lower end of the radius, converting certain grooves into 

 tunnels for the passage of the tendons ; it slopes downwards, inwards, 

 and forwards to the cuneiform and pisiform bones. 



The tendons at the back of the wrist. -Beneath the fascial 

 band are six canals for the extensor tendons, each being lined by a 

 separate synovial sheath : the outermost is for the extensors ossis 

 and primi ; the second is for the extensors radialis longior and brevior ; 

 the third, narrow and oblique, for the extensor secundi internodii ; the 

 fourth, wide and shallow, is for the extensors communis digitorum 

 and indicis ; the fifth, between the radius and ulna, is for the tendon 

 of the extensor minimi digiti ; and the sixth, at the back of the ulna, is 

 for that of the extensor carpi ulnaris. 



Superficial to the posterior annular ligament are the radial and the 

 posterior ulnar veins, and the radial and the dorsal ulnar nerves. 



The anterior annular ligament is the thickened band attached 

 to the prominences of the scaphoid and trapezium on the outer side, 

 and to the pisiform and unciform on the inner. It strengthens the bony 

 arch of the carpus, binds down the flexor tendons of the fingers, and 

 affords origin to certain muscles of the thumb and little finger. 



Superficial to it pass the tendon of the palmaris longus, the palmar 

 cutaneous branches of the median and ulnar nerves, the superficialis 

 volae, and the ulnar artery and nerve. 



Beneath it are the tendons of the flexors carpi radialis, sublimis and 

 profundus digitorum, and of the longus pollicis ; the median nerve and 

 the comes nervi mediani. 



The palmar fascia, continuous above with the anterior annular 

 ligament and with the insertion of the palmaris longus, spreads more 

 thinly over the muscles of the ball of the thumb and of the ball of the little 

 finger. Its median piece is extremely thick, protecting the subjacent 

 branches of the median and ulnar nerves and the superficial palmar 

 arch. It sends slips to join the sheaths of the flexor tendons of the 

 four inner digits, also to the webs of the fingers, and to the transverse 

 ligament connecting the heads of the metacarpal bones. 



