Measurement, Types, and Parts of the Pelvis

Pelvis serves to both support and protect the reproductive and other support organs. Its bones are ilium, ischium, pubis, sacrum, and coccyx.

The subdivisions for obstetrical purpose are:

1. False pelvis - the superior half, supports the uterus during late months of pregnancy and aids in directing fetus to the true pelvis.
2. True pelvis - the inferior half, facilitates true delivery of fetus.
3. Inlet - the entrance to true pelvis or the upper ring of the bone through which the infant must passed to deliver vaginally.
4. Outlet - the inferior portion of the pelvis, bounded in the back by the coccyx, greatest diameter is the antero-posterior part.
5. Pelvic cavity - the space between the inlet and outlet. Its curve slows and controls the speed of birth.

Internal Measurement of Pelvis are:

1. Diagonal conjugate - the distance between the anterior surface of the sacral prominence and the anterior surface of the inferior margin of the symphysis pubis; suggestive of antero-posterior diameter of inlet; it should be 12.5 cm to be adequate.
2. True conjugate/Conjugate vera - the distance between the anterior surface of sacral prominence and posterior surface of the inferior margin of symphysis pubis; to get this, just subtract the usual depth of symphysis pubis from diagonal conjugate. It should be 10.5 - 11.0 cm.
3. Ischial tuberosity diameter - the distance between ischial tuberosities or the transverse diameter of the outlet; 11.0 measurement is adequate.

Types of Pelvis

• Gynecoid - transversely rounded and slightly ovoid
• Android - angulated, resembles male pelvis, heart shaped
• Anthropoid - oval, wider anteroposterior diameter
• Platypelloid - flat anteroposterior diameter, wide transversely
  

Enter your email address:

Delivered by FeedBurner