/superhell/ - the seventh circle

The human anorectum is highly unsuited for many all-too-common receptive activities due to the fragility of the anorectal region. Contributing factors include:

• Anatomy — Not far inside there are very delicate and pain-insensate tissues (including simple columnar epithelium, a lining that some enemas and lubricants can inflame and even remove).
• Neuromuscular physiology — The internal anal sphincter is involuntary and relaxes with rectal distension. The external anal sphincter and puborectalis completely relax as a person bears down, causing hemorrhoidal cushions to engorge and increasing the cushions' fragility.

Potential traumatic consequences of such activities include inflammation, abrasion and tearing, damage to muscle and connective tissues, and colorectal perforation. All of those can lead to even more issues: bacterial infection followed by abscess / fistula / life-threatening systemic sepsis; hemorrhoidal disease, such as internal hemorrhoidal prolapse; rectal prolapse (originating from further inside); anatomic stenosis (narrowing due to constricting scar tissue called a stricture); one or more anal skin tags (scar tissue e.g. from a healed tear, a sentinel tag associated with a chronic anal fissure, or a remnant of external hemorrhoidal thrombosis); and fecal incontinence.

• Strong frictional sliding (aka shear) in the anal canal is likely to permanently damage supporting tissue of the internal hemorrhoidal cushions at the least, leading to internal hemorrhoidal prolapse (progressively worsening with cumulative damage from repeated trauma). Damage to one or more of the internal hemorrhoidal cushions elicits no pain sensation due to their lack of somatic innervation. As healthy internal and external anal cushions help to maintain fecal continence with a watertight seal, anal canal deformation due to their disease or removal can result in fecal incontinence (FI). Furthermore, pulling or traction on nerves in the anorectal region can potentially lead to neuropathy and associated FI.

• Internal rectal prolapse (IRP), aka rectal intussusception, is a common finding among asymptomatic individuals. Strong, repeated frictional sliding in the rectum probably does contribute to development of full-thickness external rectal prolapse (aka procidentia) particularly when IRP is present. Internal hemorrhoidal prolapse—among other conditions—also may contribute to rectal prolapse development. FI can be a consequence of rectal prolapse as well.

• Stretching the anal canal with girthy insertions is likely to disrupt or fragment one or both anal sphincter muscles, possibly without pain as the internal anal sphincter muscle also lacks somatic innervation. Such damage results in permanent muscle weakening and is associated with FI especially with a damaged or dysfunctional puborectalis muscle. Stretching the anal canal repeatedly with insertions of progressively increasing circumference may cause cumulative muscle damage.

• Trauma—including anoreceptive trauma—can instigate development of numerous other anorectal conditions that may lead to FI, such as a fistula. Additionally, surgical treatment for anorectal conditions can contribute to development of FI.

As of 2024/01/18 relevant English Wikipedia articles for many years have had major flaws. Among them:
• The "human anus" and the "perineal raphe" articles both depict a female's anus and perineum probably damaged by some kind of major trauma. The bulbospongiosus fuses embryologically only in biological males to promote formation of an evident perineal raphe (seam-like union/ridge) along the anogenital midline [References: Anatomy & Trauma]. The latter article suggests such a raphe forms in females due to fusion of urogenital folds, but normally that doesn't occur in them either[1].
• The "simple columnar epithelium" article explains neither its fragility nor (at least in the anorectal region) absence of somatic innervation.

The "anal sex" article …
• lacks neutrality; it gives the impression that opposition is limited to irrational religious positions by omitting any _scientific_ opposing perspective, e.g.: The human anorectum is very unsuited for many common receptive activities due to the region's anatomy and physiology. The single short-term benefit, _potential_ pleasure, is greatly outweighed by the many short- and long-term health risks to a receptive person.
• fails to mention the normalization of injurious anorectal violence in pornography featuring real people.
• does not disambiguate "hemorrhoid(s)," which can refer to pathology or normal anatomy. Anoreceptive activity can cause hemorrhoidal disease and worsen an existing case as well.
• contains a logically-fallacious appeal to nature.

Since many people seem to rely on Wikipedia (regardless of whether they should or not), those flaws contribute to rampant anorectal violence along with misinformation facilitating it.

1. "Anatomy and physiology of the clitoris, vestibular bulbs, and labia minora with a review of the female orgasm and the prevention of female sexual dysfunction." Clinical Anatomy. 2013 Jan; 26(1): 134-52. doi:10.1002/ca.22177. (PMID 23169570)

>Reddit /r/painal
Other subreddits which clearly violate Reddit's policy on violent content quoted below yet strangely [as of 2024/01/18] persist nonetheless: /r/Roughanal /r/DegradingHoles

"Do not post content that encourages, glorifies, incites, or calls for violence or physical harm against an individual (including oneself) or a group of people…"
https://web.archive.org/web/20230719232538/https://support.reddithelp.com/hc/en-us/articles/360043513151
Also relevant: "Note that health misinformation, namely falsifiable health information that encourages or poses a significant risk of physical harm to the reader, also violates the Rule."

For far too many years now the subreddits mentioned above have been encouraging, glorifying, and inciting anorectal violence in particular that arguably should easily constitute severely criminal behavior when more than one person is involved (at the very least for potentially-lethal outcomes/sequelae). Perhaps people at high levels of Reddit should be held accountable: not only for failing to uphold their own site's policies, but also for enabling the spread of very dangerous violent behavior along with health-harmful falsehoods and omissions facilitating it on subreddits such as /r/sex.

Traumatic risks of human anoreceptive activities include inflammation; abrasion and tearing; muscle and connective tissue damage; and colorectal perforation. Sequelae may arise, such as hemorrhage/hematoma, hemorrhoidal disease, ulceration, bacterial infection followed by abscess / fistula / life-threatening systemic sepsis, rectal prolapse, fecal incontinence, anal skin tag (remnant of external hemorrhoidal thrombosis, scar tissue from a healed tear, or a sentinel tag for a chronic anal fissure), and anatomic stenosis (narrowing due to constricting scar tissue). One instance of trauma can lead to multiple complications. Cumulative damage and preexisting conditions are concerns too.

~2cm beyond the anal opening at the pectinate/dentate line, the epithelium transitions from stratified squamous (anoderm) to simple columnar in part of the narrow surgical anal canal, continuous with the rectum. This very fragile mucosal lining is easily damaged especially if its mucus barrier is removed by an enema or otherwise impaired. Furthermore, some enemas and lubricants can inflame the lining and even cause it to slough off. Since injury to anorectal mucosa alone is painless due to a lack of somatic innervation, resultant problems may remain undetected with no obvious symptom(s).

Neuromuscular physiology also contributes to anorectal fragility particularly for girthy and vigorous insertions, which are objectively foolish and very likely to be significantly injurious. The involuntary internal anal sphincter relaxes with rectal distension. The puborectalis and external sphincter completely relax when a person bears down, causing hemorrhoidal cushions to engorge and become more susceptible to being injured by frictional sliding, aka shear. The internal hemorrhoidal cushions lack somatic innervation as well.