INTRODUCTIONThe term “vermiform” comes from latin word and means “worm shaped”.The vermiform appendix is a blind ended tube connected to the cecum from which is develops embryologically.
DEFINITIONVermiform appendix is a vestigial organ. Atubular structure of about 8cm with a lumenattached the cecum.
VESTIGIALITYA vestigial structure is a structure that has lost all or most of its original function through the process of evolution. The main function of appendix is to digest cellulose with the help of mutualistic bacteria. As the human appendix no longer houses a significant amount of these bacteria and humans are no longer capable of digesting more than a minimal amount of cellulose per day. Thus human appendix is considered as a vestigial organ.
SIZE AND LOCATION The appendix averages 11 cm in length but can range from 2 -20 cm. The diameter of appendix is usually between 7 and 8 mm.
The appendix is located near the junction of the small intestine and large intestine in right lower quaderant of the abdomen near the right hip bone.
Appendix position within the abdomen corresponds to a point on the surface known as Mc burney’s point.
Thelocation of the tip of the appendix can vary.
FEATURES Found at the point where the taniae coli converge on the postero medial wall of caecum. It opens into the caecum at one end and the other end is blind. Mesoappendix :-a peritoneal fold enclosing the appendicular vessels. It is the prolongation of the mesentry of the terminal ileum. The tip of the appendix lies at the level of the brim of the pelvis.
STRUCTURE OF APPENDIX Varies considerably in length and circumference. The lumen of the appendix is narrow. Peritoneal layer-serosa
muscular coat of longitudinal and circular muscle layer. It has well developed submucosa coat containing lymphoid tissue. The lumen has longitudinal fold of mucous membrane and contains intestinal debris.
BLOOD SUPPLY TO THE APPENDIX The arterial supply of the appendix is by means of the appendicular artery,inferior branch of of the ileocecal artery of the superior mesentric trunk. The appendicular vein , ranch of ileocecal vein, drains appendicecal venous network into the superior mesentric vein and eventually into the portal circulation.
LYMPH SUPPLY The lymph vessels drain into one or two nodes lying in the mesoappendix,fom there the lymph passes through a numer of mesentric nodes to reach the superior mesentric nodes. nerve supply The nerve of the appendix are derived from sympathetic and parasympthetic (vagus) nerve from the superior mesentric plexus.
FUNCTIONS OF VERMIFORM APPENDIX Maintain homeostatic :- the endocrine cells present in appendix contribute to biological control mechanism. Immune function :- during the early years of development, the appendix has been shown to function as a lymphoid organ, assisting with the Maturation of B lymphocytes and production of antibodies IgA.
Provide direction to lymphocytes :- appendix is involved in the production of molecules that help to direct the movement of lymphocytes to various other location in the body. Maintaining gut flora :- the tube like structure of appendix helps in the proper movement of waste matter in the digestive system.
Provide surface :- appendix serves a haven for useful bacteria when illness flushes those bacteria from the rest of the intestine. It serve the vital function of repopulating the gut with beneficial bacteria after a dirrhoea like desentry.
Probiotic function:- help to have proper digestion and a healthy colon. helps protect from harmfull bacteria. helps in maintaining digestive system’s function. maintain high energy level and proper immune system function. helps in maintaining body’s vital hormone and chemical balance
SECONDARY FUNCTION OF APPENDIXUse of appendix in reconstructive surgery:- The appendix is used to recreat a sphincter muscles in the bladder surgeries so that the patient can continent the urin. In the disease of ureter the appendix allow urin to flow from the kidney to the bladder.