332 



THE ABDOMEN AND PELVIS 



in the caecal (retro-csecal) fossa, (b) It may be plastered on to 

 the posterior aspect of the caecum by the peritoneum, and it 



FIG. 104. Diagrams to illustrate the varying relationships of the Caecum, 

 the Vermiform Process and the Ascending Colon to the Peritoneum. 



1. Absence of caecal fossa ; posterior wall of caecum not covered by peritoneum. 



2. Normal condition. Caecal fossa present. 



3. Csecal fossa extending upwards behind ascending colon. Vermiform process retro- 

 caecal in position but surrounded by peritoneum. 



4. Vermiform process retro-caecal in position but enclosed by the peritoneum surround- 

 ing the caecum. 



5. As i but vermiform process is entirely extra-peritoneal. 



6. Prolapse of caecum. 



7. " Undescended caecum." The terminal part of the ileum, as it ascends to the 

 caecum, is retro-peritoneal. The vermiform process is extra-peritoneal except at its tip, 

 which is lying in front of the kidney in the posterior wall of the hepato-renal recess. 

 The ascending colon and the right colic flexure form a "double-barrelled " colon. 



8. Ascending colon with persisting mesentery, such as is met with in intussusception. 

 Note. The dotted line represents the position of the lumbo-sacral articulation. 



then lies in the anterior wall of the fossa, (c) In cases where 

 the caecum is not covered by peritoneum posteriorly,, the retro- 



