PELVIC CAVITY
The pelvic cavity is the body cavity, bounded by the pelvic girdle, anteriorly, posteriorly and laterally, by the pelvic floor, below, and by the so-called pelvic entrance, above.
Between the abdomen and the perineum, the pelvic cavity has a characteristic funnel shape.
Inside the pelvic cavity, large arteries, veins, muscles, nerves and very important organs (the so-called pelvic organs) take place, including:The bladder, located just behind the pubic symphysis;The rectum, located approximately in the center of the posterior part of the pelvis, immediately in front of the borderline between the sacrum and the coccyx;
The sigmoid colon (or sigmoid colon), located to the left of the rectum and communicating with it.The uterus, fallopian tubes, ovaries and vagina in women;
The prostate, the vas deferens and the seminal vesicles in man.
Most anatomical descriptions of the pelvic cavity report that the pelvic cavity can be divided into two regions: an upper, called the large pelvis or false pelvis, and a lower, called the small pelvis or true pelvis.
The large pelvis is a space shared with the abdominal cavity; the small pelvis, on the other hand, is the actual pelvic cavity, the one that includes the aforementioned organs.
PELVIC FLOOR
Also known as the pelvic diaphragm, the pelvic floor is a rhomboid area, consisting predominantly of muscle tissue and to a lesser extent connective tissue, extending from the pubic symphysis to the coccyx.
The pelvic floor – especially its muscle tissue – has two important functions: one function is to close the pelvic cavity below and to support the load of the pelvic and abdominal organs; the other function, on the other hand, is to control the openings towards the outside of the rectum and urogenital organs, by means of special perforations on the muscle tissue and connective tissue (the so-called rectal hiatus and urogenital hiatus).
In essence, therefore, the pelvic floor must guarantee a support action, towards the bladder, rectum, organs of the reproductive system, etc., and, at the same time, must ensure the passage, through its constituent tissues, of those anatomical structures that open outwards.
The muscle tissues of the pelvic floor belong to two very important muscles, certainly known to most, which are: the levator ani muscle and the coccygeal muscle.PERINEUMIn humans, the perineum is the anatomical area, in the shape of a lozenge, corresponding to the lower end of the pelvis.
Underlying the pelvic floor, it traces the extension from the pubic symphysis to the coccyx.
Looking at it from the outside, it is the area of the human body which, in the coccygeal-pubic direction, goes from the anus to the genital organs (vulva, in women, and testicles, in men) and which, in a transverse direction, is between the two thighs.
The perineum includes several muscles (including the external anal sphincter muscle, the urethral sphincter muscle, the bulbospongiosus muscle, the superficial transverse perineal muscle, and the deep transverse perineal muscle), connective tissue, collagen fibers, skin tissue, subcutaneous tissue, and ligaments.
According to the most traditional anatomical descriptions, it can be divided into two semi-triangles having the base in common: the so-called urogenital triangle, anteriorly, and the so-called anal triangle, posteriorly.The urogenital triangle contains the genital organs, while the anal triangle encloses the anus.