Rectal prolapse traumatizes rectal neuromuscular microstructure explaining persistent rectal dysfunction.
OBJECTIVE
Internal rectal prolapse is common and correlates with age. It causes a plug-like physical obstruction and is a major cause of defecation disorder. The progressive distortion of the prolapsing rectum likely causes secondary defects in the rectal wall, which may exacerbate rectal dysfunction. We undertook a prospective observational study to detect and quantify the neurologic and histopathologic changes in the rectal wall.


METHODS
We examined dorsal and ventral rectal wall specimens from consecutive patients with internal rectal prolapse undergoing stapled transanal rectal resection (STARR). We subjected specimens to histopathologic and neuropathologic assessment, including immunohistochemistry. We also recorded patients' clinical and demographic characteristics and sought correlations between these and the pathologic findings.


RESULTS
We examined 100 specimens. The severity of rectal prolapse and the extent of descent of the perineum correlated significantly with age. Concomitant hemorrhoidal prolapse was noted in all male patients and in 79 % of female patients. Muscular and neuronal defects were detected in 94 and 90 % of the specimens, respectively. Only four specimens (4 %) were free of significant structural defects.


CONCLUSIONS
Rectal prolapse traumatizes the rectum causing neuromuscular defects. The tissue trauma is due to shearing forces and ischemia caused by the intussusception. This initiates a self-reinforcing vicious circle of physical and functional obstruction, further impairing rectal evacuation and causing constipation and incontinence. The correlation between extent of prolapse and age suggests that internal rectal prolapse can be considered a degenerative disorder. Neural and motor defects in the wall of the rectum caused by rectal prolapse are likely irreversible.
Department of General and Visceral Surgery, Coloproctology, St. Barbara-Klinik, Hamm, Germany. mkraemer@barbaraklinik.de.
Matthias
http://orcid.org/0000-0001-9018-922X
M
Kraemer
Institute of Neuropathology, University-Hospital, Westfälische Wilhelms-Universität, Münster, Germany.
Werner
W
Paulus
Department of General and Visceral Surgery, Coloproctology, St. Barbara-Klinik, Hamm, Germany.
David
D
Kara
Department of General and Visceral Surgery, Coloproctology, St. Barbara-Klinik, Hamm, Germany.
Saskia
S
Mankewitz
Institute of Neuropathology, University-Hospital, Westfälische Wilhelms-Universität, Münster, Germany.
Stephanie
S
Rozsnoki
D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D019841:Defecography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009469:Neuromuscular Junction / Q000473:pathology* / Q000503:physiopathology*; D012005:Rectal Prolapse / Q000150:complications / Q000503:physiopathology* / Q000601:surgery; D012007:Rectum / Q000473:pathology* / Q000503:physiopathology*
Megarectum; Obstructed defecation; Rectal dysfunction; Rectal hyposensitivity; Rectal inertia; Rectal prolapse