457 



lexer carpi radialis, which lies in the groove on the greater multangular between 

 the attachments of the ligament to the bone. On its volar surface the tendons of 

 the Palmaris longus and Flexor carpi ulnaris are partly inserted; below, it gives 

 origin to the short muscles of the thumb and little finger 



Median nerve 

 Palmaris longus 

 Flex. poll. long. 

 Flex. carp. rod. 

 Radial artery 



Abd. poll. long. 

 Ext poll brev. 



Ext. carp. rad. long. 



Flexor dig. sublimis 



Ulnar artery 

 Ulnar nerve 



Flex. carp. uln. 



Flex. dig. profundua. 



Ext. carp. uln. 

 Distal radio-ulnar artic. 



Ext. carp. rad. brev. 



Ext. poll. long. 



Ext. indicia, prop. \ Ext. dig. quinti prop. 



Ext. dig. commun. 

 Fio. 421. Transverse section across distal ends of radius and ulna. 



The Mucous Sheaths of the Tendons on the Front of the Wrist. Two sheaths envelop 

 the tendons as they pass beneath the transverse carpal ligament, one for the 

 Flexores digitorum sublimis and profundus, the other for the Flexor pollicis 

 longus (Fig. 423). They extend into the forearm for about 2.5 cm. above the 

 transverse carpal ligament, and occasionally communicate with each other under 



Median nerve Transverse carpal ligament 



Flex. poll, long 

 Flex, carpi rad. 

 Muscles of thumb 



Palmaris Longus 



Flex. dig. sublimis 



Ulnar art. and nerve 



Abd. pott. long. 

 Ext. poll. brev. 



Ext. carp, rad, long. 



Radial artery 



Ext. carp. rad. brev. 



Ext. poll, long. 



Muscles of little finger 



Flex. dig. profundus 



Ext. carp. uln. 

 Ext. dig. quinti prop. 



Ext. dig. communis 

 Ext. indicis prop. 

 FIG. 422. Transverse section across the wrist and digits. 



the ligament. The sheath which surrounds the Flexores digitorum extends down- 

 ward about half-way along the metacarpal bones, where it ends in blind diverticula 

 around the tendons to the index, middle, and ring fingers. It is prolonged on 

 the tendons to the little finger and usually communicates with the mucous 



