Anatomy of the Cecum and Appendix

00:01 So let's have a look at the cecum and the appendix. The appendix is quite redundant in humans. It has no function in some lower order species, but it's quite redundant in the human and it kind of helps to pump these some lymphatic properties, but it also can be a site of infection.

00:18 The cecum and the appendix, so the cecum is the beginning part of the large intestine.

00:23 It's really formed where the ileum joins the large intestine, ileocecal junction. And here we see the cecum, we see the terminal ileum, and we have the ileocolic junction there. The opening where food can pass into the cecum from the ileum is the ileal papilla which were seen elsewhere before if you think of the major duodenal papilla. Coming away from the cecum, we have the appendix and we have a very small opening that leads from the cavity of the cecum into the appendix and food can pass into that space and that can sometimes lead to infection, inflammation, which can lead to appendicitis perhaps. The position of the appendix can be highly variable. So here we can see in the vast majority, we have a retrocecal appendix.

01:10 In other places, we can see it's located in various different ways and there's various different names and percentages for how much they are found in that different location.

01:20 I'm not sure, you'll have to look in your own course and your own learning objectives as to how much you need to know. But it's really just an indication of the variation of the appendix and how that can be found within the cecum and the large intestine. I'm not sure I'd really require my shoes to remember what are these percentages. It's highly variable so make sure you have a good look for it if you have access to a cadaver or appreciate its location in the living patient. It's important to be able to recognize the location of the appendix within the living patient as I've just said and we've talked about this when we looked at surface anatomy of the abdomen just briefly, but it's worthwhile going over again. If you were to draw a diagonal line from the umbilicus all the way to the anterior-superior iliac spine on the right side of the abdomen. Remember the appendix is located on the right side of the abdomen, then a diagonal line from the umbilicus down to the anterior-superior iliac spine 2/3 of the way from the umbilicus. So 2/3 of the way from the umbilicus to the ASIS, anterior superior iliac spine, you'll find McBurney's point and that's where palpation can lead to some guarding and some sensitivity around the area indicating an acute appendicitis which we can see here.