140 NON-SPECIFIC OR GENERAL DISEASES 



terior faces of this region are travelled by the long tendons 

 belonging to the extensor and flexor muscles of the digit. 



The digit or toe is formed by six bones, three of which are 

 termed accessory or sesamoids. The digital bones may be given 

 numerical names. 



The approximal or first digital bone is the shortest long 

 bone in the bodv. The two shallow articular cavities belonging 

 to the superior extremity are completed posteriorly by the two 

 sesamoid bones. The inferior extremity is smaller than the 

 superior and resembles the inferior extremity of the cannon 

 bone in shape, excepting that it shows a middle groove. The 

 anterior and posterior faces are travelled by the tendons of the 

 digital muscles. 



The middle or second digital bone is quite short. It articu- 

 lates superiorly with the first, and inferiorly with the third bone 

 of the digit. The superior face shows two shallow cavities, and 

 the inferior two convex surfaces separated by a median groove. 

 The latter face articulates with the third and navicular bones. 

 The popular name for this articulation is the coffin joint. 



The third or distal digital bone may be compared to a cone 

 that has been cut away posteriorly, obliquely downwards and 

 backwards. The superior face shows two shallow cavities that 

 are completed posteriorly by the superior face of the cofiin or 

 navicular bone. The anterior face is convex and cribblod by 

 openings, and the inferior face is concave, forming the sole. 

 Tendons belonging to the digital muscles terminate on the sum- 

 mit and inferior face of this bone. 



The pelvis or haunch is formed by a single bone, the coxa, 

 that in the foetus may be divided into three bones. These are the 

 ilium, pubis and ischium. It belongs to the class of flat bones. 

 Anteriorly it is flattened from before to behind and directed 

 inward and upward. The external angle is rugged and is gener- 

 ally termed the angle of the haunch. The internal face of the 

 opposite angle articulates with the sacrum, to which it is firmly 



