Similar mechanisms of traumatic rectal injuries in patients who had anal sex with animals to those who were butt-fisted by human sexual partner

Sexual pleasure comes in various forms of physical play, for many it involves stimulation of the vagina, while the anus for others; some enjoy both. A recent report by Cappelletti et al.¹ shows a meta-analysis of cases describing anal trauma due to sexual fisting in human partners. This clinical article reports four cases of males diagnosed with zoophilia, and who received anal sex from animals, resulting in injuries. Surgical and psychiatric evaluations are summarized. Unusual etiology of sexual activity with animals caused peri-anal trauma in men who engaged in anal sex with dogs and farm animals. Injuries to patients who receive anal sex from animals are mechanistically similar to fisting-induced rectal damage. Among zoophiles, the mode of harm occurs through blood-engorged, interlocked penis that causes tissue lacerations upon retraction from an anus. In people experimenting with fisting, repetitive stretching within anal canal and of external sphincter causes the internal injuries. The mode of physical stimulation explains the extent of injuries in fisters vs. zoophiles: in fisting, the pressure applied by hand is controllable proximally around and within anal sphincter, while penetration by the animal penis is unpredictable and occurs within the proximal anal canal. Forensically, the findings presented in this article describe a significant mechanism of injury in fisters versus passive zoophiles. These descriptions may aid in clinically differentiating pleasurable and pathological rectal stimulation.