SDR L6 - Anatomy of the Pelvis I Flashcards
1) Conjugal (AP) Diameter (part of Pelvic Inlet)
2) Ischial Diameter (Pelvic Outlet)
These are the two important diameters that restrict the pelvis
Pubic Tubercle
In the anatomical position the ASISs and the (1) are in the same vertical plane
Sacral Promontory
The Conjugal Diameter is the distance from the (1) in the back to the pubic symphysis in the front
Ischial Spines
The Ischial Diameter is the distance between the two (1)
1) Estrogen
2) Relaxin
3) 15%
Hormones like (1) and (2) released during labor help to relax the pubic symphysis in order to help expand these diameters by about ~_____% to help with parturition
1) S2-4
2) Posterior/Lateral
3) Sacrospinous
The pudendal nerve originates from the anterior rami of (1) then loops ((anterior/posterior)* to the ischial spine and (3) Ligament and enters the perineum
1) Inferior Rectal
2) Perineal
Once it passes around the ischial spine the pudendal nerve gives off the (1) nerve, after which point the pudendal is called the (2) nerve.
1) Dorsal Nerve of the Penis or Clitoris
The perineal nerve continues down after the ischial spine, and gives off the (1)
T
(T/F) The pudendal nerve innervates the entire perineum
Transvaginally (with a guiding finger that palpates the sacrospinous ligament)
The preferred method of implementing a pudendal block is (transvaginally/transcutaneously)
1) Size: M = thicker/heavier
2) Subpubic Angle: F > 90; M < 90
3) Inlet Shape: F = Round; M = Heart
4) Outlet Size: F = larger
5) Ischial Spines: M = inward protrusion; F = No inward protrusion
5 main differences between the male and female pelvis
Pelvic Diaphragm
Pelvic floor aka
Levator Ani muscles
Dr. Dym collectively referred to the pelvic floor muscles as the
1) Fecal Continence (Puborectalis Muscle)
2) Increase intrabdominal pressure
3) Prevent Prolapse of abdominal components
Functions of the pelvic floor muscles
F (Relaxes to remove the angle)
(T/F) The defecation reflex constricts the puborectalis muscle to remove the angle between the rectum and anal canal, which allows feces to be excreted
1) Urogenital Triangle
2) Anal Triangle
The perineum is a diamond shaped area below the pelvic floor composed of these two triangles
1) Pubic Symphysis
2) Ischial Tuberosities
3) Sacrum
The perineum is bounded anteriorly by the (1), laterally by the (2), and posteriorly by the (3)
1) UG Diaphragm
2) Roots of external genitalia
3) Skin/superficial fascia
The perineum has 3 main layers. From superior to inferior they are
External Urethral Sphincter
UG Diaphragm aka
1) Pelvic
2) Urogenital
The (1) Diaphragm is superior and makes up the entire
floor of the pelvis while the (2) Diaphragm is inferior and is only found in the urogenital triangle
F (2 in F; 1 in M)
(T/F) The UG Diaphragm is mainly responsible
for suspending the roots of the external genitalia, so there will be one opening in it in females and two in males
Perineal Membrane
Inferior Fascia of the UG Diaphragm aka (there is also a less imp superior fascia)
1) Bulb
2) Crura
The erectile tissue suspended from the UG Diaphragm is comprised of a (1) and two (2)
Ischioanal Fossa (Common site of abscess)
These are triangular spaces lateral to the pelvic viscera that are filled with liquid fat. Their role is to maintain flexibility of the area to accommodate feces
Perineal Body
The integrity of this part of the pelvic floor is important for entire region b/c 8 pelvic floor muscles converge here. Tear may lead to prolapse.
Episiotomy
A procedure sorta common during childbirth, where an incision is made in order to prevent a jagged tear that would heal slower and be harder to stitch up
1) Infection
2) Pain
3) Longer healing times compared to no tear at all
4) Increased discomfort when resuming intercourse
Downsides of Episiotomies (4)
T (Due to the fact that the fallopian tubes are open to the peritoneum at the proximal end)
(T/F) Female perineal infections can lead to peritonitis
Bartholin’s Glands
Cysts in these glands are common in women (2% of all women will have them), especially in women aged 20-29
1) UGD
2) Urethra
3) Vagina
In females the deep perineal pouch contains these three things
1) UGD
2) Membranous Urethra,
3) Bulbourethral (Cowper’s) glands
In males the deep perineal pouch contains these three things
1) Erectile Structures of the Penis
2) Proximal Spongy Urethra
In males the superficial perineal pouch contains these three things
1) Erectile Structures of the Clitoris
2) Bartholin’s Glands
In females the superficial perineal pouch contains these three things
The Superior and Inferior Fascia of the UGD
The Deep Perineal Pouch is between
The Inferior Fascia of the UGD and superficial fascia of the perineum
The Superficial Perineal Pouch is between
L4
As the aorta descends it branches into the common iliac arteries at this vertebrae
1) Iliolumbar A.
2) Lateral Sacral A.
3) Superior Gluteal A. (Largest)
The posterior division of the of the internal iliac has 3 arteries
1) umbilical
2) superior vesical (vesical=bladder)
3) inferior vesical/vaginal
4) middle rectal
5) obturator
6) internal pudendal
7) inferior gluteal
8) Uterine
The anterior division of the of the internal iliac has 3 arteries
Ureter
The (1) passes posterior/inferior to the uterine artery
Superficial Inguinal Nodes
Lymph from the perineum first drains into the
1) Great Saphenous Vein
2) Inguinal Ligament
Superficial Inguinal Nodes are arranged in
a ‘T’ with the trunk of the ‘T’ overlying the (1) and the cross of the ‘T’ lying parallel and directly inferior to the (2)
Genitals –> Superficial Inguinal Nodes –> Deep Inguinal Nodes –> External Iliac Nodes –> Common Iliac Nodes –> Aortic Nodes
The pathway of lymph from the genitalia
L4-S4
The sacral plexus is made up of the anterior rami from these vertebrae
L4-S3
The Sciatic N. is made up of the anterior rami from these vertebrae
1) External Genitalia
2) buttocks
3) uterus (via the round ligament)
4) lower anal canal
5) legs
6) trunk/back below the umbilicus.
6 regions that drain to the Superficial Inguinal Nodes
