T H E various positions whic+i may be occwpietl by tlie v e~~n~i f o r n i iippendix are well known; the figures given by diEerent authorities as to the relative frequency of these positions vary considerably, and in a general way fill1 into two main groups which are contradictory.Wakeley and Gladstone,(l) following an examination of 5,000 subjects, state that the appendix is 1-etrocaecal or retrocolic in 64.38%. Wakeley,(z' in another aidicle based on 10,000 subjects quotes a similar percentage. Collins(3' found 25% retrocaecal a t operation aiid 20% in 4,680 autopsies. Meyer and Spivack"" state that 9% of appendices were found in the retrocaecal position, while the percentage quoted by Busher(5' and Kelly("' agrees with those of Collins. I n my own series of 105 appeiidicectomies in the past eighteen months, 16 appendices were retrocaecal.It is most probable that the discrepancy in the figures resultR fidoni varying ideas as to the meaning of the term "retrocaecal appendix". A large proportion of the subjects in the series of Wakeley and Gladstone were examined in the dissecting room. Most of the other series quoted were based on operative findings, and the term retrocaecal was reserved for those appendices which were held posterios to tlie caecum either by adhesions or by virtue of a retroperitoneal position (either behind the parietal peritoneum or underneath the visceral peritoneum covering the c*aec.nni) for ;I whole or part of their length. Those appendices lying beliintl the raeciini but freely movable were excluded ; their position is almost certainly not constant.X a~i a u , (~) in challenging some earlier figures of Lafforgue with regard to the position of the appendix, pointed out that post-mortem positions did not agree with the incidence of abscesses operated upon. He iiisuffiated the caecum and discovered that the position assumed by the appendix depended on the amount of distension in the caecum. He Rtates that the appendix is the most mobile of organs, and with increasing distension the appendix will keep changing its position until finally it points up behind the caecum.There seems to be little doubt that inflammation OCCIII~S more comn~only in appendices that are in the reti3ocaecal position than in those in other sites. Kelly@) suggests that this is due to an abnormal degree of friction to which the appendix is subjected by contraction of the psoas muscle. Rusher(5) says that acute inflammation is three times as frequent in retrocolic and five times as frequent in retroperitoneal appendices a s it is in those in other sites.In the personal series mentioned above every one of the retrocaecal appendices was acutely inflamed aiid most were ganpenous ; though this 'Accepted for publication on October 1 7 , 1939.
