Anatomy of vaginal canal anal

The perineum is the space between the anus and scrotum in the male and between the anus and the vulva in the female. There is some variability in how the boundaries are defined. The perineum is an erogenous zone for both males and females. The perineum is generally defined as the surface region in both males and females between the pubic symphysis and the coccyx. The perineum is below the pelvic diaphragm and between the legs. It is a diamond-shaped area that includes the anus and, in females, the vagina.

Here, we will discuss the relevance of pelvic floor to the anal opening and closure function, and discuss new findings with regards to the role of these muscles in the vaginal and urethra closure mechanisms. The bony pelvis is composed of sacrum, ileum, ischium, and pubis. It is divided into the false greater and true lesser pelvis by the pelvic brim. The sacral promontory, the anterior ala of the sacrum, the arcuate line of the ilium, the pectineal line of the pubis and the pubic crest that culminates in the symphsis pubis. The shape of the female bony pelvis can be classified into four broad categories: gynecoid, anthropoid, android, and platypelloid. The pelvic diaphragm is a wide but thin muscular layer of tissue that forms the inferior border of the abdominopelvic cavity. Composed of a broad, funnel-shaped sling of fascia and muscle, it extends from the symphysis pubis to the coccyx and from one lateral sidewall to the other.

The female pelvic floor serves to aid in the function of the lower urinary system, genital tract and rectum. The majority of the time the muscles are contracted and aid in urinary and fecal continence, and support of the genital tract. Relaxation of these muscles occurs at urination, defecation, coitus and childbirth.

In mammals , the vagina is the elastic, muscular part of the female genital tract. In humans, it extends from the vulva to the cervix. The outer vaginal opening is normally partly covered by a membrane called the hymen. At the deep end, the cervix neck of the uterus bulges into the vagina. The vagina allows for sexual intercourse and birth.