Perineal groove is a congenital malformation of the perineum characterized by a wet (nonkeratinized epithelium) sulcus spanning the region between the posterior vaginal fourchette and the anterior edge of the anus with a normally formed vestibule, urethra, and vagina. Associated congenital anomalies in girls are rare and include
anorectal stenosis, anal ectopy, and anal prolapse. When found in boys, the groove extends from the penoscrotal junction to the anterior edge of the anus and may be associated with anomalies such as
hypospadias or bifid scrotum.
The incidence of perineal groove is not known, but it is believed to be uncommon and found most frequently in girls. The pathogenesis is not completely understood, but the occurrence of the malformation in males and females suggests a possible anomaly of embryologic development common to both sexes.
The 2 types of perineal groove are:
- Complete – The sulcus extends completely from the posterior fourchette of the vagina to the anterior edge of the anus.
- Incomplete – The sulcus extends from the anus anteriorly but does not reach the posterior fourchette of the vagina.
Most lesions have a benign course and spontaneously undergo full or partial epithelialization by age 1-2 years, but some cases may take years to fully resolve. Complications are rare and include local irritation, skin infection,
urinary tract infection,
constipation, and failure to self-resolve. Additionally, there have been occasional reports of concomitant anomalies such as ectopic anus, bifid scrotum, hypospadias, and urinary tract abnormalities.