Chap. xv. j THE WRIST AND HAND. 237 



The wrist joint. The tip of the styloid process 

 of the ulna corresponds to the line of the wrist joint, 

 and a knife entered below that point would enter the 

 articulation. A knife entered horizontally just below 

 the tip of the styloid process of the radius would 

 hit the scaphoid bone. A line drawn between the 

 two styloid processes would slope downwards and 

 Outwards, its two extremities would represent the 

 extreme inferior limits of the radio-carpal joint, and 

 would fairly correspond to the chord of the arc 

 formed by the line of that joint. The line between 

 the styloid processes would be nearly half an inch 

 below the summit of the arch of the wrist joint. 



There are several folds in the skin on the front of 

 the wrist ; of these, the lowest is the most distinct^ 

 It is a little convex downwards, precisely crosses the" 

 heck of the os magnum in the line of the third m eta- 

 carpal bone (Tillaux), and is not quite three-quarters 

 of an inch below the arch of the wrist joint. It is 

 about half an inch above the carpo-metacarpal joint 

 line, and indicates very fairly the upper border of the 

 anterior annular ligament. 



The palmar surface of hand. The palm is con- 

 cave in the centre where the skin is adherent to the 

 palmar fascia. This " hollow of the hand " is of some- 

 what triangular outline, with the apex upwards. On 

 either side are the thenar and hypothenar eminences. 

 At the upper end of the former eminence, a bony pro- 

 jection is felt, just below and internal to the radial 

 styloid process, that is formed by the tubercle of the 

 scaphoid and ridge on the trapezium. The interval 

 separating these two processes of bone cannot always 

 be made out. At the upper extremity of the hypothenar 

 eminence is the projection of the pisiform bone, and 

 just below it the unciform process can be identified. 

 Below the hollow of the palm, and opposite the clefts 

 between the four fingers, three little elevations are 



