Page:Structure and functions of the body; a hand-book of anatomy and physiology for nurses and others desiring a practical knowledge of the subject (IA structurefunctio00fiskrich).pdf/187

 row are the scaphoid and semilunar bones, on the outer side, articulating with the radius, the cuneiform articulating with the fibro-cartilage of the wrist-joint, and the pisiform. In the second row, in corresponding positions, are the trapezium, trapezoid, os magnum, and unciform. The eminence felt on the radial side of the wrist is the protuberance of the scaphoid, while the pisiform is generally felt on the ulnar side.

—Right carpal bones, dorsal surface. T, trapezium; T´, trapezoid; 7, os magnum; U, unciform; S, scaphoid; L, semilunar; C, cuneiform, P, pisiform.

The Hand.—The hand contains nineteen bones, five metacarpal bones, one for each finger and the thumb, whose bases articulate with the lower row of wrist bones, and fourteen phalanges, three for each finger and two for the thumb, of which the first row articulate with the metacarpal bones. They are all long bones and are slightly concave anteriorly. When the hand is flexed it is the heads of the metacarpal bones, not the bases of the phalanges, that are so prominent, the head of the third metacarpal being most prominent.

The metacarpals are seldom fractured, though bad fractures occasionally occur. In comminuted fracture nothing can be done but remove the bone. If the periosteum is left the bone will grow again. Two diseases