Different positions of Appendix comparison between adult cadaver and dead fetus – An original report
Dr. Gattu Praveen kumar
Menashsi medical college
Appendicitis is one of the most common diseases that need emergency surgery. Variations in anatomical position cause different clinical presentations. The aim of this study is to determine the anatomical variations of the position, length and meso-appendix in operative specimens. The caecum and the appendix are the commencement of the large intestine. They are situated normally in the right iliac fossa in adults. Morphologically the appendix is the undeveloped distal end of the large caecum found in many lower animals. The position of appendix is extremely variable, more than that of any organ in the body. The present work consists of the study of the positions vermiform appendix in adult cadavers and dead fetus. The total number of specimens studied are 50, out of which 25 are adult cadavers and the rest are 25 dead fetuses freshly collected from labor rooms of the department of Obstetrics and Gynecology, Government General Hospital, Sex is noted in the adult cadavers and sex and age are noted in the fetuses.
KEY WORDS: Appendicitis, anatomical positions, right iliac fossa, adult cadavers, dead fetus.
The vermiform appendix a narrow vermian (worm shaped) tube, arising from postero-medial caecal wall, two cms or less below the end of the ileum. The vermiform appendix is suspended by a fold of peritoneum known as meso-appendix. The base of appendix lies at the junction of the lateral 1/3 rd and medial 2/3rds of the line joining the right anterior superior iliac spine and the umbilicus11 (Mc Burneys point).The maximum tenderness is located at this point acute appendicitis. The three taeniae coli on the ascending colon and caecum converge on the base of appendix merging into its longitudinal muscle. The anterior caecal taenia is distinct and traceable to the appendix. Appendix is a part of large intestine which is devoid of taeniae coli, sacculations and appendices epiploicae5.The length and diameter of appendix are variable. The length of the appendix varies from 2-20 cm. The average length being 9 cms. It is longer in children and may atrophy or diminish after mid-adult life. The average diameter at the base is 6 mm. The vermiform appendix has base, body and tip. The base is attached to the postterio-medial wall of the caecum about 2 cms below the ileo caecal junction. All the taeniae of the caeca converge to the base and serve as a guide for the identification of the appendix. The body is a narrow and tubular and contains a canal which opens in to the caecum by an orifice lying below and a little behind the ileo-ceacal opening. The opening of the appendix in to the caecum sometimes is guarded by a semilunar9 mucosal fold forming a valve known as the ‘valve of Gerlach’. The lumen may be partially or wholly obliterated in later decades of life. The tip is least vascular and directed in various positions. Accordingly the position of the appendix is classified.
Retrocaecal and Retrocolic – It is the commonest type and present in more than 60 percent of cases. The appendix lies Retroperitoneally behind the caecum (Retrocaecal) and lower part of ascending colon .
Pelvic Position – It is the second commonest position and present in more than 30% of cases. The tip passes downwards and medially, crosses the pelvic brim on the right side. In females it is in close relation to the right uterine tube and ovary.
Sub-caecal Position – This is present in 2.226 percent of cases. The appendix lies below the caecum.
Splenic Position -It is present in about 1-2 percent of cases. The tip of appendix passes upwards and medially either infront or behind the ileum. It may be pre ileal or post-ileal. The pre-ileal variety is most dangerous because the inflammation from the appendix spreads to the general peritoneal cavity.
Promontoric Position -It is very rare, the tip of the appendix is directed horizontally towards the sacral promontory.
Mid – inguinal Position -It is very rare and tip is directed vertically downwards towards towards the middle of the inguinal ligament.
Sir Frederick Treves (1885) designated the various positions of the appendix to the numbers on the face of a Clock
1. 110 Clock – Paracolic
2.12 0 Clock – Retrocaecal and Retrocolic
3. 20 Clock – Splenic Position
4. 30 Clock – Promontoric Position
5. 40 Clock – Pelvic Position
6. 60 Clock – Mid-Inguinal Position
The mesentery of the appendix is known as meso-appendix it is a triangular fold of peritoneum. It arises from the lower surface of the mesentery of the terminal ileum. In childhood the meso appendix is so transparent that the contained blood vessels can be seen. In adults the meso-appendix is studded with fat and obscures the vessels. Appendicular artery, a branch of ileo-colic artery, passes behind the terminal part of ileum to enter into the meso-appendix then lie in the free border of the meso –appendix. Four to six lymphatic vessels traverse the meso- appendix which drains into the ileo-caecal lymph nodes8. Nerves also traverse the meso-appendix. But sometimes it fails to reach the distal third, and represented by a low peritoneal ridge containing fat. If the meso-appendix is incomplete the appendicular artery lies on the wall of the appendix in its distal part.
The following observations are made in the present study of vermiform appendix.
Table No.1 position of Appendix
Position No.of specimens Percentage
Retrocolic or Retrocaecal12 ‘o’ clock
Preileal 2’o’ clock position
Promonteric 3 ‘o’ clock position.
Ectopic type sub-hepatic position 3 12%
Table No. 2 Position of the tip of appendix in 25 foetuses.
Position No.of specimens Percentage
Retrocolic or Retrocaecal 12 ‘o’ clock position
Preileal 2’o’ clock position
Mid Inguinal 6 ‘o’ clock position
Promonteric 3 ‘o’ clock position.
Ectopic type sub-hepaticPosition 2 80%
Measurements : In 15 adult male specimens the length of appendix is varying from 9 cm to 4 cm with an average length of 6.02 cm. In 15 adult males the breadth of appendix at the base of varying from 1.2 cm to 0.5 cm with an average of 0.75 cm. In 10 female fetuses (40%) the length of the vermiform appendix is varying from 2 cm to 4 cm with an average length.
Out of 25 adult specimen, the meso appendix is complete in 4 specimens but in the rest of 21 specimens the meso appendix remained short of apex. In fetuses out of 25 specimens the meso appendix is complete in 16 specimens and in the remaining 9 specimens the meso appendix is not stretching to the apex .
Table no. 3 Meso appendix in adults and fetuses
Specimen Incomplete Meso appendix Complete Meso appendix
25 Adults 21 4
Percentage 84% 16%
25 foetuses 9 16
Percentage 36% 64%
Arterial supply of caecum and Appendix
The arterial supply to the caecum and appendix in the adults as well as in the fetuses derived from the iliocolic artery which is a branch given from the lower part of the right side of superior mesenteric artery. The iliocolic artery is divided into superior and inferior divisions. The inferior division is giving ascending branch (colic) anterior and posterior caecal branches and appendicular and ileal branches.
In all adult and foetal specimens the anterior and posterior caecal branches are arising from the inferior division of ileocolic artery. The appendix is supplied by appendicular artery which is a branch of lower division of iliocolic artery it is an end artery. It runs behind the terminal part of the ileum and enters the meso appendix at a short distance from its base. It runs along the free border of meso appendix it gives a recurrent branch at the base which anastomoses with a branch of posterior caecal artery. The main artery runs towards the tip of the appendix lying of first near to and them in the free border of the meso appendix. There may be an accessory appendicular artery (artery of seshachalam) arising from the posterior caecal artery out of 25 adult specimens dissected in 23 specimens. The appendix is supplied only by appendicular artery but in 2 specimens in addition to appendicular artery, the artery of seshachalam is seen arising from posterior caecal branch
Table no. 4 – Arterial supply of appendix in adults and fetuses.
Specimens Appendicular artery from inferior division of iliocolic artery Artery of seshachalam and Appendicular artery
Adult specimens 23 2
Percentage 92% 8%
Foetuses 25 —
The Vermiform appendix may occupy one of the several positions. The direction of the tip of the appendix is taken as the criterion to describe the position of the appendix. Various authors quoted different percentages of frequency of occurrence. Gray10 has described the positions as retro-caecal, retro-colic, pelvic, sub-caecal, pre-ileal and post-ileal. Wakely12 described the position of vermiform appendix as retro-caecal and retro-colic (65.28%), pelvic (31%), sub-caecal (2.26%), pre-ileal (1%) and post-ileal (0.4%). Buschard and Kjaeldgaard classified positions as anterior (pelvic and ileo caecal) and posterior (retro caecal and subcaecal). They observed posterior positions are more common in Danish people. Wakely and Gladstone, both described the positions of the appendix as retro-caecal (64%), pelvic(32%), they described that sub-caecal and splenic positions are rare. According to Lockhart the positions of vermiform appendix are retro-caecal (65%), pelvic (30% ), remaining (5%) are of sub-caecal or pre-ileal or post-ileal in position. Khan7 described the position of appendix as retro-caecal and retro-colic (65%), pre-ileal and pelvic (30%), right para colic and sub-caecal (2%) and ileo-colic (1%). Dutta classified the different positions of the appendix as sub-caecal and paracolic (2%), retro-caecal and retro-colic (60%) splenic 1-2%), promontoric (rare), pelvic (30%) and mid-inguinal which is rare.
In the present study the position of appendix in adult specimens is as follows. Preileal (8%) retro caecal (60%) Midinginal (16%) Promonteric (12%) Subhepatic (4%) These observations are not in conformity with any of the above authors because they have used different criteria.
In fetuses the positions of the appendix are observed as retro-caecal 40%, Pre-ileal 8% and mid-inguinal 20% promonteric 24%. These observations could not be compared as no proper literature is available.
It is a triangular fold of peritoneum enclosing the blood vessels, nerves and lymph vessels of the vermiform appendix. This extends to a variable length. As per Gray, Keith.L.Moore and A.K.Dutta1 the meso-appendix extends up to the tip of the appendix. As per R.J.Last and Hollinshead the meso-appendix extends to a variable length.
In 4 adult specimens of the present study the meso-appendix is complete which is in conformity with the descriptions given by Gray, Keith.L.Moore and A.K.Datta.In the rest of the specimens the extent of meso-appendix is coinciding with the findings of R.J.Last and Hollinshead2.
In 4 foetal specimens of the present study the meso-appendix is complete and in 9 foetal specimens it is incomplete. These observastions could not be compared as no proper literature is available.
Peritoneal reflections of appendix
According to wood Burne and Sahana3 the vermiform appendix is completely covered with peritoneum. In the present study also in all the adult specimens the appendix is fully covered by peritoneum which is in conformity with description given by the above authors.
In all fetuses also the appendix is fully covered by peritoneum. No literature is available regarding peritoneal covering of vermiform appendix in fetuses for comparison.
Length and breadth of appendix in adult and foetal specimens
The length of the vermiform appendix in adults varies widely from 20 mm to 250mm as described by different authors, the average ranging from 75mm to 100mm. In the present study, the length of the appendix is ranging from 40 mm to 90 mm which is within the range described by the authors shown in the table No. 22. But the average length 60 mm which is less when compared to that of the above authors Very few authors described the breadth of appendix. In the present study, the average breadth of appendix in adults is 7.8 mm which is nearer to the breadth given by Lockhart 4 and Cunningham6.
In all 25 foetal specimens, the length of the appendix is ranging from 25 mm to 50 mm and the average being 27 mm. The breadth in all 25 foetal specimens is ranging from 2 mm to 5 mm with an average of 2.5 mm. This findings could not be compared as the literature is not available.
Arterial Supply of Caecum
Regarding the origion of the ileo-colic artery G ray, Grant, Cunningham, Buchanan, Anson, R.J.Last, Morris, Nicholas and Michels, Wood Burne have described that it is arising independently from the right side of the superior mesenteric artery. In the present study in all 25 adult specimens (100%) the ileo-colic artery is arising independently from the right side of the superior mesenteric artery which is in conformity with the description of above authors.
In all foetal specimens (100%) also the ileo-colic artery is arising independently from the right side of the superior mesenteric artery.
In view of variability of positions, varying anatomical relations and clinical complications, the study of gross anatomy and arterial supply of caecum and appendix has been taken. The dissection is done in 25 adult specimens and in 25 foetal specimens. The anatomy of appendix is studied in detail. An attempt is made to draw a contrast between the adult and foetal anatomy of appendix.
The normal position of appendix in adult specimens is at the right iliac fossa, most of the fetuses the position of the caecum is in right lumbar region. In some it is in sub-hepatic position and in others it is right iliac fossa.
In all adult and foetal specimens both caecum and appendix are completely covered by peritoneum.
In 50% of adult and foetal specimens the appendix is retro-caecal in position. Other different positions of it are described in the rest of the adult and foetal specimens.
In all adult specimens and in most of the foetal specimens the terminal part of ileum is opening into the posterio-medial aspect of caecum. In rest of the fetuses the terminal part of the ileum is opening either medially or anterior-medially or anterior aspects of the caecum.
The average length and breadth of the caecum are more in male adults than in female adults. In foetal specimens the average length of the caecum is more in female than in male where as the average breadth is same in both male and female fetuses.
In both adult and foetal specimens the average length and breadth of appendix is more in males than in females. The extent of meso-appendix in most of the adult and foetal specimens is incomplete and in the rest of the specimens it is complete.
The arterial supply of caecum and appendix is studied in detail. In all adult and foetal specimens the ileo-colic artery is arising from the right side of the superior mesenteric artery. The anterior and posterior ceacal branches are arising from the interior division of ileocolic artery in all adult and foetal specimens.
In all adult specimens and in all foetal specimens, appendicular artery is single arising from inferior division of ileo-colic artery in 2 adult specimen a recurrent branch arising from the appendicular artery is anostomosing with the posteriorcaecal branch at the base of the appendix. In 2 adult specimens the appendix in supplied by appendicular artery and also by the artery of sesachalam.
All the data given above is presented as basic study about appendix. There is yet a lot of scope for further investigation, using ultra-microscope and histo-chemical techniques in a more accurate and to obtain upto date knowledge about the appendix.
Datta. K. Essentials of human Anatomy Part-I Thorax & Abdomen 6th edition; July 2003 Current books international Kolkata, Chennai. Page Nos: 192- 198.
Hollinshed. H W. Anatomy for surgeons Volume-2; Thorax, Abdomen, Pelvis May 1966, A Hoeber-Harper International edition, New York, London,
Sahana. S.N: Sahana’s Human Anatomy Descriptive and applied. Volume: II Ankur edition- July 1994 Ankur publications, Calcutta. Page Nos: 104, 362-367.
Lockhart. R.D., Hamilton. G.F: Fyfe. F. W. Anatomy of the human body, 1st edition, 1959. Faber and Faber limited; London Page Nos: 522-525, 624-626.
Singh I.B. Chaurassia human anatomy, Regional and applied. 3rd ed. Vol. 2. CBC publishers and distributors. New Delhi.1999; P: 223-5.
Romanes. G. J. Cunningham’s Manual of practical Anatomy, Volume-2, Thorax and Abdomen, 15th edition, 1993, 1998. ELBS with Oxford University press, London. Page Nos: 141-142.
Ali N, Rasul S, Mehmood. Z, Inamullah, Khan. A. Journal of surgery Pakistan 2009; 4:153- 156.
Rehman MM et all. Extent of mesoappendix of vermiform Appendix in Bangladeshi People. J Bangladesh Soc Physiol. 2009 June; 4(1): 20-23.
Sabiston DC, Courtney M. Sabiston’s Textbook of Surgery: The Biological Basis of Modern Surgical Practice in Appendix. 16th edition. Vol. 2. Philadelphia, Pa, USA: WB Saunders; 2001.
Gray’s Anatomy., 39th Ed., Lawrence. H.Bannister., Martin.M.Berry., Patrica Collin., Pages 1553, 1554, 1743, 1774, 1775 & 1785. Churchil Living Stone., Edinburgh, London, New York, Philadelphia, Sydney, Toronto.
Mc Burney1889 Started the modern manner of Surgical approach to appendix, as quoted by Michels.
Wakely C.P.C.1933The position of the vermiform appendix as ascertained by an analysis of 10,000 cases, J, Anat. 67.277-283.