. Diaphragviatocele — Diaph rag77iatic Hern ia — Ph ren ic Hern ia . 365 



otlier hand the orifice may be of almost any form, size or situa- 

 tion. It may be round, elHptical, triangular, or irregular in 

 many ways. It may be so small as to admit nothing more than 

 a small fold of the omentum, or it may be large enough to open 

 the two cavities, thoracic and abdominal into one common space, 

 and to practically abolish the function of the diaphragm. 

 If the lesion is a recent one the torn margin is irregularly indent- 

 ed or fimbriated and marked by small black blood clots, and 

 somewhat later by exudate and irregular thickening or swelling. 

 When due to a broken rib, the existence of the fracture is patent 

 and the laceration extends along two lines often radiating from 

 point of perforation by the rib. When the laceration has resulted 

 from tympany of the stomach or intestines or from other over- 

 distension of the abdominal organs, the general and comparatively 

 equable pressure has determined the independent laceration of 

 numerous tendinous or muscular bundles all over the diaphragm, 

 so that the divided ends stand out at intervals each bearing its 

 little clot of dark blood, but without actual perforation. The 

 actual orifice in such cases is confined to one point where the 

 tension has been greater or the resistance less. Pos^ viorteni 

 lacerations, from tympany or other cause, are easily distinguished 

 from those occurring during life, in that the edges of the wound 

 are pale and bloodless, wifhout clot or exudate. 



When the hernia is chronic there is an absence of exposed 

 fringes, and of indications of inflammation, the margins of the 

 orifice being in some ca.ses smooth, even and fibrous, and in 

 others irregularly notched or indented with nodular, fibroid 

 swellings of various sizes at intervals. In such cases the orifice is 

 always relatively small and the hernial mass inconsiderable. 



As a rule the peritoneum and pleura, being firmly adherent to 

 the diaphragm, are involved in the laceration so that the hernial 

 mass is not retained in a special sac, but simply protrudes into the 

 pleural cavity, after the manner of an eventration. In excep- 

 tional cases they become detached from the muscle, and becoming 

 di.stended, envelope the hernial mass in a di.stinct sac. 



In hernia with a very small orifice the omentum alone may 

 pass through, even the small intestine proving too large for ad- 

 mission. In such cases it is usual to find the band of omentum 

 adherent to the callus formed by the repair of a fractured rib. 



