294 SKELETON. 



bone touches the adjacent one. The joint is furnished with a 

 capsular ligament and a synovial membrane. 



The Capsular Ligament surrounds the articulation, passing 

 on every side from the upper lo the lower row, and adhering 

 strongly to the bones. It is in a great degree a continuation 

 of the capsule of the radio-carpal joint, and has, at the same 

 points, an increase of thickness, called after the same names. 

 The internal lateral ligament is attached by one end to the cu- 

 neiforme, and by the other to the side of the unciforme. The 

 external lateral ligament arises from the extremity of the sca- 

 phoides, and is inserted into the side of the 'trapezium. The 

 posterior and anterior ligaments have the course of their fibres 

 more distinctly seen on the side of the synovial membrane. 

 The first consists in many fibres arising from the bones of the 

 first row and going to the second row; its fibres are shorter 

 and more compact. The anterior arises and is inserted after 

 the same way, some of them terminating in the anterior liga- 

 ments of the hand. 



The Synovial Membrane is not only displayed on the oppo- 

 site surfaces of the two carpal rows, but also is reflected upoft 

 the lateral faces of the bones belonging to each row. It, there- 

 fore, sends processes, two of which are found, above; one be- 

 ivveen the scaphoides and the lunare, and the other between 

 the lunare and cuneiforme. These processes are arrested at 

 their upper extremities by the fibro-cartilaginous matter be- 

 tween the bones, which was spoken of in the radio-carpal ar- 

 ticulation. It also sends three processes downwards, one be- 

 tween the trapezium and the trapezoides. another between the 

 latter and the magnum, and the third between the magnum and 

 the unciforme. Those latter processes communicate with or 

 are continuous with the synovial membrane, between the car- 

 pal and the metacarpal bones of the fingers.* The connexions 

 and reflections of this membrane are of the greatest impor- 

 tance, as they form a commonieation from the top of the wrist 

 to the base of the metacarpal bones; not only covering the ar- 

 ticular surfaces, but being prolonged in some instances beyond 



* Eicliat, Anat. Dcscr 



