The elephant’s other bits

Abstract

In this issue of the journal Dr. Murad-Regadas et al. present a retrospective analysis of 255 women who had undergone defecography for constipation according to the Rome Criteria [1]. This is a very interesting paper that tackles a subject with substantial implications for the aetiology of conditions that we know rather little about. There is no doubt that research into the potential aetiological contribution of childbirth should have a high priority, since there is such widespread disagreement regarding the definitions of rectocele and rectal intussusception, and since we are far from achieving consensus on treatment. In short, Murad-Regadas found that neither rectocele nor anismus nor rectal intussusception were associated with vaginal parity. These findings are in disagreement with some of our own data, and I wonder whether this may be an artefact of study design, and maybe also an artefact of the imaging methodology used in this study, resulting in reduced power and type II errors. To start with, it is usually advantageous to define hypotheses to be tested, such as ‘‘Mode of delivery is associated with defecography findings’’ (which would require a comparison of vaginally parous women against C/S) or ‘‘Parity is associated with defecography findings’’ (which requires a comparison of nulliparae vs. parous women). Another issue is the role of confounders, such as age. Nulliparae were substantially younger, and rectocele is clearly associated with age. A multivariate analysis may have been useful. And I do not quite understand the numbers trail. It seems not one patient had had both C/S and vaginal deliveries, which is, after all, quite common. Another issue is definitions. Rectal intussusception is a particularly interesting condition that is the subject of a just-completed study at my unit. One of the problems in assessing the literature on the subject is the definition of intussusception actually is. In agreement with Anders Mellgren, a colorectal surgeon with a long-standing interest in the twilight zone between Gynaecology and Coloproctology, I would suggest that rectal intussusception is an invagination of the rectal ampulla, propelled by a ‘peritoneocele’ containing small bowel, sigmoid, or, rarely, the uterine cervix, omentum or just fluid [2]. Mucosal infolding (which is often misdiagnosed as intussusception) seems to be a very different condition and probably of limited consequence. One of the main effects of modern pelvic floor imaging is that it has the potential to make colorectal surgeons, urologists and gynaecologists talk to each other as never before, and even more important, to make us understand each other. This invited commentary is plain evidence of this trend, and I for one am excited by the potential for collaboration. So far, we have all viewed the pelvic floor from very different perspectives, the urologist, as it were, from the perspective of the cystoscopist, the gynaecologist through a vaginal speculum, and the colorectal surgeon/ gastroenterologist through the sigmoidoscope. Not surprisingly, we all ended up identifying different parts of the proverbial elephant in the dark. It’s time for all of us to acknowledge that other specialties and subspecialties may have an important contribution to make to the overall picture, so that we may ultimately end up perceiving the elephant in its true form and function. This comment refers to the article doi:10.1007/s10151-009-0533-z.