252 SURGICAL APPLIED ANATOMY. [Chap. xv. 



that the middle finger is, from its greater length, 

 the one most exposed to injury and to shocks received 

 by the fingers. Its metacarpal bone is directly 

 received by the strongest carpal bone, the os magnum, 

 and the latter bone is brought by means of the 

 semi-lunar in connection with the widest and strongest 

 part of the radius. 



But little movement is allowed in the metacarpo- 

 carpal joints of the first three fingers, but in the like 

 joints of the thumb and little finger movements are 

 free, and their preservation is of great importance to 

 the general usefulness of the hand. The glenoid liga- 

 ments in front of the three finger-joints are firmly 

 attached to the distal bone, and but loosely to the 

 proximal. Thus it happens that in dislocation of the 

 distal bone backwards, the glenoid ligament is carried 

 with it, and offers a great obstacle to reduction. In 

 flexing the second and third finger joints alone, it will 

 be seen that the first phalanx is steadied by the ex- 

 tensor tendon as a preliminary measure, and in 

 paralysis of the extensors flexion of these two joints 

 alone is not possible. 



Very few persons have the power of flexing the 

 last finger joint without at the same time bending the 

 articulation above it ; but in certain inflammatory 

 affections about the last phalanges the terminal joint 

 is sometimes seen to be fixed in a flexed posture while 

 the other finger joints are straight. I imagine that 

 this position must always indicate some disease of the 

 articulation itself. 



Colles' fracture. This name is given to a 

 transverse fracture through the lower end of the 

 radius, from a half to one inch above the wrist joint. 

 It is associated with -a certain definite deformity, and 

 is always the result of indirect violence, a fall upon 

 the outstretched hand. There are good reasons why 

 the bone should break in this situation. The lower 



