Chap, xv.] THE WRIST AND HAND. 26 j 



especially the palm, is singularly free from surface 

 veins. Indeed, the great bulk of the blood from the 

 hand is returned by the superficial veins on the 

 dorsum of the fingers and hand. 



The lymphatics of the palm are, moreover, scanty, 

 and very minute, whereas on the dorsum they are 

 large and profusely distributed. The ulnar border of 

 the palmar part of the hand is much used in pressure 

 and in "hammering" movements, and it is significant 

 that this surface is well protected by soft parts, and 

 presents a singular absence of large nerves, that, if 

 present, would be liable to sustain damage from such 

 movements. 



The form of the nail varies somewhat in individuals, 

 and, according to certain authors, there are special 

 types of nail to be met with in some constitutional 

 diseases. Thus are described the tubercular, the 

 rachitic, the arthritic nail. By the Hippocratic hand 

 is meant a hand the tips of the fingers of which are 

 clubbed, and the nails of which are much curved. 

 This condition would appear to be due to impeded 

 circulation, to retardation in the return of venous 

 blood, and perhaps also to imperfect oxygenation of 

 that blood. It is most often met with in congenital 

 heart disease, in phthisis, empyema, chronic lung 

 affections, certain thoracic aneurisms, and some forms 

 of scrofula.* There are several forms of inflammation 

 affecting the matrix of the nail and the soft parts 

 immediately around it (onychia, paronychia). Such 

 inflammations lead to great deformity of the structure 

 itself. When a nail is thrown off by suppuration or 

 violence a new nail is produced, provided any of the 

 deeper epithelial cells are left. During convalescence 

 from certain illnesses (e.g., scarlet fever), a transverse 

 groove will appear across all the nails. This groove 



* See " Scrofula and its Gland Diseases," p. 99. By the 

 Author. London. 1882. 



