pelvic diaphragm - definition of pelvic diaphragm in the Medical dictionary - by the Free Online Medical Dictionary, Thesaurus and Encyclopedia.

diaphragm /di·a·phragm/ (di´ah-fram)

1. the musculomembranous partition separating the abdominal and thoracic cavities and serving as a major muscle aiding inhalation.

2. any separating membrane or structure.

3. a disk with one or more openings or with an adjustable opening, mounted in relation to a lens or source of radiation, by which part of the light or radiation may be excluded from the area.

4. a device of molded rubber or other soft plastic material, fitted over the uterine cervix before intercourse to prevent entrance of spermatozoa.diaphragmat´ic

contraceptive diaphragm diaphragm (4).

pelvic diaphragm the portion of the floor of the pelvis formed by the coccygeal and levator ani muscles and their fasciae.

polyarcuate diaphragm one showing abnormal scalloping of the margins on radiographic visualization.

Potter-Bucky diaphragm see under grid.

respiratory diaphragm diaphragm (1).

urogenital diaphragm traditional but no longer valid concept that fascial layers enclose the sphincter urethrae and deep transverse perineal muscles and together form a musculomembranous sheet that extends between the ischiopubic rami.

vaginal diaphragm diaphragm (4).

pelvic diaphragm

The paired coccygeal muscle and elevator muscle of the anus with the fascia above and below them.

pelvic diaphragm,

the inferior aspect of the body wall, stretched like a hammock across the pelvic cavity and comprising the levator ani and the coccygeus muscles. It holds the abdominal contents, supports the pelvic viscera, and is pierced by the anal canal, the urethra, and the vagina. It is reinforced by fasciae and muscles associated with these structures and with the perineum.

diaphragm

1. the musculomembranous partition separating the thoracic and abdominal cavities. On its sides, it is attached to the caudal ribs; ventrally to the sternum; at the back, to the spine. The esophagus, the aorta and vena cava, and nerves pass through the diaphragm. When relaxed, the diaphragm is convex but it flattens and moves caudally as it contracts during inhalation, thereby enlarging the chest cavity and allowing for expansion of the lungs. See also respiration.

2. any separating membrane or structure.

3. a disk with one or more openings or with an adjustable opening, mounted in relation to a lens, by which part of the light may be excluded from the area.