1. Pelvis and Perineum
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- 4 Bones that make up the Bony Pelvis:
-
-Sacrum (S1-S5)
-Coccyx
-2 Innominate bones - (ox coxal or hip bone) - 3 components of the hip bone:
-
-Ilium
-Ischium
-Pubic bone - What are 3 important structures on the hip bone?
-
1. Acetabulum
2. Lesser sciatic notch
3. Greater sciatic notch - What articulates with the acetabulum?
- Head of femur
- What makes up the acetabulum?
-
ALL THREE hip bone components:
-Ilium
-Ischium
-Pubic bone - Lesser Sciatic Notch is the concavity between:
-
Ischial Spine
Ischial Tuberosity - Greater Sciatic notch is located
-
Superior to Ischial spine
-Formed b the ilium in part - 2 Important spaces created by the bony pelvis:
-
-True pelvis (lesser)
-False pelvis (greater) - Boundaries of True pelvis:
-
-Below iliopectineal line
-Between pelvic inlet and outlet - Function of True Pelvis:
- Contains and protects parts of the GI, GU, and reproductive structures
- Contents of True Pelvis:
-
-Rectum
-Uterus/Fallopian tubes (Female)
-Prostate (male)
-Bladder - Boundaries of False Pelvis:
-
Above pectineal line
Posterior: Spinal cord
Anterior: abdominal walls - Contents of False Pelvis:
- Abdominal viscera - of little importance
- Sacrum consists of:
- 5 fused vertebrae S1-S5
-
Parts of Sacrum that Articulate:
-with what? -
Anterior/Lateral
-With iliac crests - Important feature of Sacrum:
- Promontory - creates posterior wall of pelvis
- 5 important Pelvic ligaments:
-
1. Anterior longitudinal
2. Iliolumbar
3. Posterior sacroiliac
4. Sacrospinous
5. Sacrotuberous - What forms the GSF/LSF?
-
-Sacrospinous Lig (separates them)
-Sacrotuberous Lig (inferior) - Functions of Sacrospinous and Sacrotuberous ligaments:
-
-Prevent excess superior /posterior rotation of inferior aspect of sacrum
-Support weight of vertebral column. - Bony components of Obturator Foramen:
-
-Pubic ramus
-Ischial ramus - 3 things pass thru the Obturator Canal:
-
-Obturator nerve
-Obturator Artery
-Obturator Vein - What is the obturator canal?
- A small hole in the membrane over the obturator foramen.
- Plane of Pelvic Inlet runs between what 2 points?
-
-Tip of Sacral Promontory
-Superior edge of Pubic Symphysis - Linea terminalis runs along what 3 points?
-
1. Sacral promontory
2. Arcuate line (iliac)
3. Pectineal line - Plane of Pelvic Outlet runs between what two points?
-
1. Sacrum S5
2. Inferior edge of Pubic Symphysis -
Dimensions of avg female pelvic outlet:
-Transverse
-Anteroposterior -
Transv: ~11 cm
Ant/post: ~9.5-11.5 cm - What is the Conjugate diameter?
- another name for the plane of the pelvic inlet
- Avg length of the conjugate diameter:
- ~11 cm
- What is the Pelvic Axis?
- A line in the MEDIAN PLANE - ALWAYS at the center piont of the pelvic cavity - this means it ANGLES around pubic symphysis.
-
Pubic Arch:
-Males
-Females -
-Males = < 90 degrees
-Females = > 90 degrees -
If cement poured into pelvis, how would it flow in the
-Male
-Female -
Male = convergant
Female = Divergant - What is the preferred type of pelvis for delivery?
- Gynecoid
- 2 Spaces created by the Pelvic Diaphragm:
-
1. Intra-pelvic (visceral)
2. Ischiorectal - Where is the intrapelvic space?
- Superior to pelvic diaphragm
- Where is the ischiorectal fossa?
-
-Inferior to pelvic diaphragm
-Posterior to UG diaphragm - What muscles make up the Pelvic Diaphragm?
-
-Levator Ani
-Coccygeus - 3 components of Levator Ani:
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1. Puborectalis
2. Pubococcygeus
3. Iliococcygeus - What is the importance of Puborectalis?
-
-Forms a sling
-Maintains fecal continence - What is Levator Ani innervated by?
-
-Perineal branches of S3-S4
-Inferior rectal nerve - What is the Coccygeus muscle innervated by?
- S4,S5
- What is the IMPORTANT FUNCTION of levator ani?
- MAIN SUPPORT FOR PELVIC VISCERA
- What muscle is adjacent to the pelvic diaphragm?
- Piriformis