pelvic diameter


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Related to pelvic diameter: true pelvis, bony pelvis, conjugata vera

diameter

 [di-am´ĕ-ter]
the length of a straight line passing through the center of a circle and connecting opposite points on its circumference; hence the distance between the two specified opposite points on the periphery of a structure such as the cranium or pelvis.
cranial d's (craniometric d's) imaginary lines connecting points on opposite surfaces of the cranium; the most important are biparietal, that joining the parietal eminences; bitemporal, that joining the extremities of the coronal suture; cervicobregmatic, that joining the center of the anterior fontanel and the junction of the neck with the floor of the mouth; frontomental, that joining the forehead and chin; occipitofrontal, that joining the external occipital protuberance and the most prominent midpoint of the frontal bone; occipitomental, that joining the external occipital protuberance and the most prominent midpoint of the chin; suboccipitobregmatic, that joining the lowest posterior point of the occiput and the center of the anterior fontanel.
pelvic diameter see pelvic diameter.

pelvic

 [pel´vik]
pertaining to the pelvis.
pelvic diameter any diameter of the pelvis. The diagonal conjugate joins the posterior surface of the pubis to the tip of the sacral promontory; the external conjugate joins the depression under the last lumbar spine to the upper margin of the pubis; the true or internal conjugate is the anteroposterior diameter of the pelvic inlet, measured from the upper margin of the pubic symphysis to the sacrovertebral angle; the oblique joins one sacroiliac articulation to the iliopubic eminence of the other side; the transverse diameter of the inlet joins the two most widely separated points of the pelvic inlet; and the transverse diameter of the outlet joins the medial surfaces of the ischial tuberosities.
pelvic inflammatory disease any pelvic infection involving the upper female genital tract beyond the cervix; such diseases are a major cause of female infertility.

pelvic diameter

Etymology: L, pelvis, basin; Gk, diametros, measuring across
1 at the rim of the pelvis, a line from the lumbosacral angle to the symphysis pubis.
2 at the pelvic outlet, a line from the tip of the coccyx to the lower border of the symphysis pubis.

diameter

the length of a straight line passing through the center of a circle and connecting opposite points on its circumference; hence the distance between the two specified opposite points on the periphery of a structure such as the cranium or pelvis.

cranial d's, craniometric d's
imaginary lines connecting points on opposite surfaces of the cranium.
pelvic diameter
any of the diameters of the pelvis; any measurement that expresses the diameter of the birth canal in the female.
References in periodicals archive ?
Their radiological examination of pelvic diameters of women at least 37 weeks pregnant, studied the dorsal lithotomy position as well as during the McRoberts' manoeuvre (hyper flexion of the woman's legs onto her chest).
Russell's 1969 study of pelvic x-rays of 96 women in the last trimester of pregnancy in both the dorsal and sitting positions identified the gains that can be made to increase all pelvic diameters by positional changes (Russell, 1969).
These include facilitation of alignment of the presenting part to the pelvic axis, encouragement of the mother's efforts toward giving birth, allowing for larger pelvic diameters, improving comfort, and promoting fetal well being, she advised.