Female Pelvis Flashcards
Plane of Pelvic Inlet
Imaginary line joining the following points:
Upper border of symphysis pubis.
Superior pubic ramus.
Iliopectineal eminence.
Iliopectineal line.
Sacroiliac joint.
Ala of sacrum.
Pubic tubercle.
Pubic crest.
Promontory of sacrum.
Other points on opposite side.
Diameters of Pelvic Inlet
Diameters of Pelvic Inlet
- AP
Diameters of Pelvic Inlet
Diameters of Pelvic Inlet
- Transverse
Diameters of Pelvic Inlet
- Other Diameters
Length of True Conjugate (Anatomical AP - Conjugata Vera)
11cm
Extent of True Conjugate (Anatomical AP - Conjugata Vera)
- Tip of sacral promontory
to
- Posterior part of upper border of symphysis pubis
Importance of True Conjugate (Anatomical AP - Conjugata Vera)
Divided by anatomical transverse diameter into:
- Anterior sagittal diameter of inlet (7 cm)
- Posterior sagittal diameter of inlet (4 cm)
Length of Obstetric Conjuate Diameter
10.5 cm
Extent of Obstetric Conjuate Diameter
- Tip of sacral promontory
to
- Most bulging point on posterior surface of symphysis pubis
Importance of Obstetric Conjuate Diameter
- Most important A-P diameter it is the shortest one through which fetus must pass)
Length of Diagonal Conjugate Diameter
12.5 cm
Extent of Diagonal Conjugate Diameter
- Tip of sacral promontory
to
- Lower border of symphysis pubis
Importance of Diagonal Conjugate Diameter
- Can be measured clinically & approximate length of true conjugate is calculated by subtracting 1.5 cm.
Length of Anatomical Transverse Diameter
13 cm
Extent of Anatomical Transverse Diameter
() 2 farthest points on iliopectineal line
Importance of Anatomical Transverse Diameter
Divides true conjugate into:
- Anterior sagittal diameter of inlet (7 cm)
- Posterior sagittal diameter of inlet (4 cm)
Length of Obstetric transverse Diameter
12 cm
Extent of Obstetric transverse Diameter
Bisects true conjugate diameter
Importance of Obstetric transverse Diameter
The available transverse diameter for head (the shortest)
Length of Oblique Diameters
12 cm
Extent of Oblique Diameters
- Sacroiliac joint on one side
to
- Iliopectineal eminence on the other side.
Importance of Oblique Diameters
Named (Rt or Lt) according to joint & Lt diameter is slightly shorter than Rt due to:
- More frequent use of Rt leg,
- Encroachment of sigmoid colon on Lt diameter.
Length of Sacrocotyloid Diameters
9-9.5 cm
Extent of Sacrocotyloid Diameters
- Center of sacral promontory.
to
- Iliopectineal eminence
Importance of Sacrocotyloid Diameters
Named (Rt or Lt) according to eminence
Plane of Obstetric Midpelvis
- Importance
Diameters of Anatomical Outlet
- AP
- Transverse (bituberous)
- Anterior Sagittal
- Posterior Sagittal
Diameters of Anatomical Outlet
- AP
Diameters of Anatomical Outlet
- Transverse (Bituberous)
Diameters of Anatomical Outlet
- Anterior Sagittal
Diameters of Anatomical Outlet
- Posterior Sagittal
Thorn’s (Klein’s) Dictum
- To allow average sized fetal head to pass through pelvic outlet → bituberous diameter + posterior sagittal diameter of pelvic outlet must be > 15 cm provided that bituberous diameter is > 8 cm.
Diameters of Bony Pelvis (Summary)
- Pelvic Inlet
Diameters of Bony Pelvis (Summary)
- Plane of GPD
12 cm all round
Diameters of Bony Pelvis (Summary)
- Plane of MP
Diameters of Bony Pelvis (Summary)
- Plane of LPD
Diameters of Bony Pelvis (Summary)
- Anatomical Outlet
Classification of Female Pelvis
Classification of Female Pelvis is based on ……
Caldwell & Moloy have classified female pelvises based on radiological studies into four types
Gynecoid Pelvis
- Incidence
- Pelvic Inlet
- Sacrum
- Pelvic Cavity
- Sunpubic Angle
- Head Engagment
- Pelvic Reserve Capacity
- Clinical Importance
Android Pelvis
- Incidence
- Pelvic Inlet
- Sacrum
- Pelvic Cavity
- Sunpubic Angle
- Head Engagment
- Pelvic Reserve Capacity
- Clinical Importance
Anthropoid Pelvis
- Incidence
- Pelvic Inlet
- Sacrum
- Pelvic Cavity
- Sunpubic Angle
- Head Engagment
- Pelvic Reserve Capacity
- Clinical Importance
Platypelloid Pelvis
- Incidence
- Pelvic Inlet
- Sacrum
- Pelvic Cavity
- Sunpubic Angle
- Head Engagment
- Pelvic Reserve Capacity
- Clinical Importance
Compare between Gtnecoid, Android, Anthropoid, Platypelloid Pelvis in terms of:
- Incidence
- Pelvic Inlet
- Sacrum
- Pelvic Cavity
- Sunpubic Angle
- Head Engagment
- Pelvic Reserve Capacity
- Clinical Importance
Incidence of Gynecoid Pelvis
50 %
Pelvic Inlet in Gynecoid Pelvis
oval
Pelvic Inlet in Android Pelvis
- Triangular with narrow anterior segment & wide flat posterior segment
Head Engagment in Android Pelvis
In transverse diameter