532 SURGICAL APPLIED ANATOMY. [Chap. xxui. 



produced by falls upon the sole or by extreme supi- 

 nation (rotation outwards) of the foot, whereby the 

 astragalus is forced violently against the process. 



The astragalus alone may be broken by a fall upon 

 the feet, and such accidents are often associated with 

 fractures of both that bone and the os calcis. It 

 must be noted, however, that in a fall, when the 

 patient alights upon the feet, the tibia and fibula are 

 much more likely to be broken than are the tarsal 

 bones, since the bones of the leg transmit the weight 

 of the body directly, whereas that weight is much 

 diffused, and broken-up when passing through the foot 

 with its many bones and joints. 



The metatarsal bones and phalanges are nearly 

 always broken by direct violence. I had, however, 

 under my care at the London Hospital a man who 

 had broken the shafts of the three outer metatarsal 

 bones by simply slipping off the edge of the curb. 



With regard to the luxations of the foot not yet 

 considered, it may be said that the cuboid is never 

 dislocated only. Walker reports a case of dislocation of 

 the scaphoid alone, that structure being quite separated 

 from the astragalus and cuneiform bones. The acci- 

 dent was brought about by alighting upon the ball of 

 the foot when jumping, and the little bone was found 

 projecting on the dorsum. Mr. Bryant has mentioned 

 an instance of dislocation of the scaphoid inwards. 

 As a rule, however, this bone when displaced is 

 dislocated along with the astragalus. 



Of the cuneiform bones the one most often lux- 

 ated alone is the internal. The attachment of the 

 tendons of the tibialis anticus and peroneus longus 

 about the internal cuneiform and first metatarsal 

 bones renders it common for the latter to follow 

 its tarsal colleague when dislocated. Mr. Luke 

 has recorded a case of incomplete luxation of 

 all three cuneiform bones upwards, and at least 



