Understanding "Hernia in the Rectum"
The term "hernia in the rectum" is not technically accurate medical terminology, but people often use this phrase to describe rectal prolapse, which is a circumferential, full-thickness protrusion of the rectum through the anus—not a true hernia. 1, 2
What Rectal Prolapse Actually Is
Rectal prolapse is a herniation of the rectum through the anal canal, involving either just the mucosal layer or the full thickness of the rectal wall. 3, 4
This condition differs fundamentally from a true hernia because it represents an intussusception (telescoping) of the rectal wall rather than a defect in the abdominal wall with organ protrusion through it. 2
The key distinguishing feature is concentric protrusion of rectal tissue, which differentiates it from prolapsed hemorrhoids that show radial bulging of discrete anal cushions. 1
Who Gets Rectal Prolapse
This condition can occur at any age but shows a bimodal distribution: children under 4 years (due to anatomical variants) and adults over 65 years (prevalence of 1%). 5, 4
Women are affected 9 times more frequently than men, with chronic straining during defecation, menopause, vaginal multiparity, and pelvic floor muscle weakness being the primary risk factors. 5
Chronic constipation with repetitive straining is the most common predisposing factor, causing mechanical stretching and eventual failure of the rectovaginal septum, levator ani muscles, and endopelvic fascia. 6, 5
Previous pelvic surgeries can contribute to pelvic floor denervation injury, increasing stress on fascial support structures. 6, 5
True Pelvic Hernias That Can Involve the Rectum
While rectal prolapse itself is not a hernia, there are actual hernias that can affect the rectal area:
Enterocele is a true pelvic hernia formed from separation of endopelvic fascia, where small bowel herniates into the pelvis and can present as anterior rectal prolapse. 7
Rectocele is defined as a hernia of the rectum with protrusion of the anterior rectal wall through the posterior vaginal wall, affecting 30-50% of women over age 50. 8
Pouch of Douglas protrusion (peritoneocele) is often confused with rectal intussusception but represents herniation of peritoneum and is best addressed with sacrocolpopexy. 1
Critical Clinical Pitfall
Any patient presenting with rectal prolapse requires colorectal cancer screening, as rectosigmoid cancer prevalence is 5.7% in patients with rectal prolapse compared to 1.4% in age-matched controls—representing a 4.2-fold increased relative risk that mandates endoscopic examination. 1, 6
When to Seek Emergency Care
Irreducible or strangulated rectal prolapse requires urgent evaluation, as patients may develop bowel ischemia, perforation, or peritonitis. 1
Hemodynamically stable patients with irreducible prolapse should undergo urgent contrast-enhanced abdomino-pelvic CT scan to detect complications, while unstable patients require immediate surgical management without imaging delays. 1