The ligaments connecting the pisiform bone are the articular capsule and the 

 two volar ligaments. 



The articular capsule is a thin membrane which connects the pisiform to the 

 triangular; it is lined by synovial membrane. 



The two volar ligaments are strong fibrous bands; one, the pisohamate ligament, 

 connects the pisiform to the hamate, the other, the pisometacarpal ligament, joins 

 the pisiform to the base of the fifth metacarpal bone (Fig. 334) . These ligaments 

 are, in reality, prolongations of the tendon of the Flexor carpi ulnaris. 



Articulations of the Distal Row of Carpal Bones. These also are arthrodial 

 joints; the bones are connected by dorsal, volar, and interosseous ligaments. 



The Dorsal Ligaments (ligamenta intercarpea dorsalia). The dorsal ligaments, 

 three in number, extend transversely from one bone to another on the dorsal 

 surface, connecting the greater with the lesser multangular, the lesser multangular 

 with the capitate, and the capitate with the hamate. 



The Volar Ligaments (ligamenta intercarpea wlaria; palmar ligaments'). The 

 volar ligaments, also three, have a similar arrangement on the volar surface. 



The Interosseous Ligaments (ligamenta intercarpea interossea). The three inter- 

 osseous ligaments are much thicker than those of the first row; one is placed be- 

 tween the capitate and the hamate, a second between the capitate and the lesser 

 multangular, and a third between the greater and lesser multangulars. The first 

 is much the strongest, and the third is sometimes wanting. 



Articulations of the Two Rows of Carpal Bones with Each Other. The joint 

 between the navicular, lunate, and triangular on the one hand, and the second 

 row of carpal bones on the other, is named the midcarpal joint, and is made up of 

 three distinct portions: in the center the head of the capitate and the superior 

 surface of the hamate articulate with the deep cup-shaped cavity formed by the 

 navicular and lunate, and constitute a sort of ball-and-socket joint. On the 

 radial side the greater and lesser multangulars articulate with the navicular, and 

 on the ulnar side the hamate articulates with the triangular, forming gliding joints. 



The ligaments are: volar, dorsal, ulnar and radial collateral. 



The Volar Ligaments (ligamenta intercarpea wlaria; anterior or palmar ligaments). 

 The volar ligaments consist of short fibers, which pass, for the most part, from 

 the volar surfaces of the bones of the first row to the front of the capitate. 



The Dorsal Ligaments (ligamenta intercarpea dorsalia; posterior ligaments). 

 The dorsal ligaments consist of short, irregular bundles passing between the dorsal 

 surfaces of the bones of the first and second rows. 



The Collateral Ligaments (lateral ligaments') .The collateral ligaments are very 

 short; one is placed on the radial, the other on the ulnar side of the carpus; the 

 former, the stronger and more distinct, connects the navicular and greater mul- 

 tangular, the latter the triangular and hamate; they are continuous with the 

 collateral ligaments of the wrist-joint. In addition to these ligaments, a slender 

 interosseous band sometimes connects the capitate and the navicular. 



Synovial Membrane. The synovial membrane of the carpus is very extensive (Fig. 336), 

 and bounds a synovial cavity of very irregular shape. The upper portion of the cavity inter- 

 venes between the under surfaces of the navicular, lunate, and triangular bones and the upper 

 surfaces of the bones of the second row. It sends two prolongations upward between the navic- 

 ular and lunate, and the lunate and triangular and three prolongations downward between 

 the four bones of the second row. The prolongation between the greater and lesser multangulars, 

 or that between the lesser multangular and capitate, is, owing to the absence of the interosseous 

 ligament, often continuous with the cavity of the carpoimetacarpal joints, sometimes of the 

 second, third, fourth, and fifth metacarpal bones, sometimes of the second and third only. In 

 the latter condition the joint between the hamate and the fourth and fifth metacarpal bones 

 has a separate synovial membrane. The synovial cavities of these joints are prolonged for a 

 short distance between the bases of the metacarpal bones. There is a separate synovial mem- 

 brane between the pisiform and triangular. 



