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.
Pelvic outlet | |
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Details | |
Identifiers | |
Latin | apertura pelvis inferior |
TA98 | A02.5.02.009 |
TA2 | 1290 |
FMA | 17273 |
Anatomical terms of bone |
Boundaries edit
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.[1]
Notches edit
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 edit
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 edit
Additional images edit
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Articulations of pelvis. Anterior view.
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Articulations of pelvis. Posterior view.
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Low-dose CT scan of sagittal pelvic outlet diameter as part of pelvimetry
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Intertuberous diameter, as a measure of the transverse measure of the pelvic outlet
References edit
- ^ 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 edit
- pelvis at The Anatomy Lesson by Wesley Norman (Georgetown University) (medialpelvissmall, malepelvissagittalinlet&outletsml)