Reflex anal dilation (RAD) is the

reflex In biology, a reflex, or reflex action, is an involuntary, unplanned sequence or action and nearly instantaneous response to a stimulus. Reflexes are found with varying levels of complexity in organisms with a nervous system. A reflex occurs ...

ive dilation of the human

anus The anus (Latin, 'ring' or 'circle') is an opening at the opposite end of an animal's digestive tract from the mouth. Its function is to control the expulsion of feces, the residual semi-solid waste that remains after food digestion, which, d ...

to a diameter greater than two centimeters in response to the parting of the buttocks or anal stimulation, such as brushing with a medical instrument. RAD was theorized to be a clinical marker associated with anal

sexual assault Sexual assault is an act in which one intentionally sexually touches another person without that person's consent, or coerces or physically forces a person to engage in a sexual act against their will. It is a form of sexual violence, whi ...

in children, and has been associated with other signs of sexual assault but also appears in children with severe chronic

constipation Constipation is a bowel dysfunction that makes bowel movements infrequent or hard to pass. The stool is often hard and dry. Other symptoms may include abdominal pain, bloating, and feeling as if one has not completely passed the bowel moveme ...

and those subject to invasive medical treatments of the anus. The finding of RAD alone is not considered indicative of

sexual abuse Sexual abuse or sex abuse, also referred to as molestation, is abusive sexual behavior by one person upon another. It is often perpetrated using force or by taking advantage of another. Molestation often refers to an instance of sexual assa ...

, and a normative sample of children not suspected of having been sexually abused found that 49 per cent of children showed anal dilation either continuously or intermittently, though the dilation exceeded 20 mm in only 1.2 per cent of cases. In 1986, Marietta Higgs learned of the RAD connection with sexual assault at a conference where it was presented by Christopher J Hobbs. Higgs used this RAD diagnosis extensively the following year, leading to the Cleveland child abuse scandal. It was discredited during the trial as the sole indication of sexual abuse, determined to be considered a sign of sexual assault by a tiny minority of British doctors. RAD as a clinical marker for sexual abuse is now considered discredited. However Hobbs was still studying RAD in 2014.

References

{{Reflist, 2 Anus Child sexual abuse Reflexes Sexual abuse

See also

References