| Pelvic outlet | |
|---|---|
 Diameters of inferior aperture of lesser pelvis (female) | |
 Muscles of the female perineum | |
| Details | |
| Identifiers | |
| Latin | apertura pelvis inferior |
| TA98 | A02.5.02.009 |
| TA2 | 1290 |
| FMA | 17273 |
| Anatomical terms of bone[edit on Wikidata] | |
The lower circumference of the lesser pelvis is very irregular; the space enclosed by it is named the inferior aperture or pelvic outlet. It is an important component of pelvimetry.
Boundaries
It has the following boundaries:
- anteriorly: the pubic arch
- laterally: the ischial tuberosities
- posterolaterally: the inferior margin of the sacrotuberous ligament
- posteriorly: the anterior border of the middle of the coccyx.
Notches
These eminences are separated by three notches:
- one in front, the pubic arch, formed by the convergence of the inferior rami of the ischium and pubis on either side.
- The other notches, one on either side, are formed by the sacrum and coccyx behind, the ischium in front, and the ilium above; they are called the sciatic notches; in the natural state they are converted into foramina by the sacrotuberous and sacrospinous ligaments.
In situ
When the ligaments are in situ, the inferior aperture of the pelvis is lozenge-shaped, bounded as follows:
- in front, by the pubic arcuate ligament and the inferior rami of the pubes and ischia
- laterally, by the ischial tuberosities
- behind, by the sacrotuberous ligaments and the tip of the coccyx.
See also
Additional images
-
Articulations of pelvis. Anterior view.
-
Articulations of pelvis. Posterior view.
-
Low-dose CT scan of sagittal pelvic outlet diameter as part of pelvimetry
-
Intertuberous diameter, as a measure of the transverse measure of the pelvic outlet
References
- Sara Paterson-Brown, Phillip Bennett, Catherine Williamson (2010). Basic Science in Obstetrics and Gynaecology (Fourth Edition) - Obstetric pelvic definitions and dimensions. Elsevier Ltd. ISBN 978-0-443-10281-3.
{{cite book}}: CS1 maint: multiple names: authors list (link)
External links
- pelvis at The Anatomy Lesson by Wesley Norman (Georgetown University) (medialpelvissmall, malepelvissagittalinlet&outletsml)
| Bones of the pelvis | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| General | |||||||||||
| Ilium |
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| Ischium |
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| Pubis |
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| Compound | |||||||||||