Horseshoe appendix

A case of a
horseshoe appendix. The diagram of the specimen. a The orifice of the cecum. b The orifice of the ascending colon. (i) The mesentery of the appendix, (ii) tenia of colon, (iii) the ileum
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Congenital
abnormalities and anatomical variations of the vermiform appendix and mesoappendix: Modified Cave-Wallbridge classification. Type A, partial duplication of the appendix; Type B1 (bird type), two appendices are placed symmetrically on both sides of the ileocecal valve; Type B2 (taenia coli type), one appendix is in the usual place and the other is far along the taenia coli; Type C, duplication of cecum and appendix; Type D (horseshoe type), one appendix has two openings in the cecum; Bulut et al. (2016).
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A case of a
horseshoe appendix. A 30-mm-wide mass in the ascending colon
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A case of a
horseshoe appendix. A mass connected with the appendix. Tumor invasion derived from the ascending colon or appendix suspected
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Case report
of the duplex vermiform appendix: A rare presentation in an elderly patient: Table 1. Showing the modified Cave-Wallbridge classification
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A horseshoe appendix is an extremely rare variant of the vermiform appendix, in which the appendix arises from the cecum and curves back on itself to re-insert into the cecum, similar to a semicircular canal in the inner ear.

Epidemiology

Anatomic variation of the appendix is extremely rare. In a study of 50,000 appendix surgical specimens by Donald C Collins, an American general surgeon and pathologist, appendiceal agenesis was only seen in four cases, and duplication was seen in two cases, a prevalence of 0.004%. But no cases of horseshoe appendix were seen . In total eleven cases of horseshoe appendix have been reported in the English medical literature with a further four in the Chinese literature .

Gross anatomy

The appendix forms a loop with two appendiceal orifices and in theory at least acute appendicitis should be less likely as it is no longer a blind-ending tube, although at least one case has been described .

History and etymology

The first case was described as recently as 1989 by Thomas W Mesko, an American surgeon, and colleagues .

Siehe auch:
Assoziationen und Differentialdiagnosen zu Hufeisenform der Appendix vermiformis:
Lageanomalien
der Appendix vermiformis
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Duplikation
der Appendix vermiformis
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