Anatomy part 1 Flashcards
Identify the
- sacral promontory
- ala of sacrum
- arcuate line of ilium
- pecten pubis
- pubic tubercle
- pubic crest
.
What is the inferior pelvic outlet bounded by
- anteriorly
- laterally
- posteriorly
Anterior - pubic arch
Lateral - ischial tuberosities + sacrotuberous ligaments
Posterior - tip of coccyx
Lesser pelvis also known as the
True pelvis
Compared to males, the following features of the female pelvis are
- greater pelvis - depth
- lesser pelvis - width + depth
- pelvic inlet - shape
- pelvic outlet - size
- subpubic angle
shallower wider + shallower oval/round larger - to allow baby to exit >90 degrees
Sacroiliac is what type of joint
Synovial plane
Pubic symphysis is what type of joint
Secondary cartilaginous
Muscles forming these walls of the pelvic cavity
- lateral
- posterior
- floor
Lateral - obturator internus
Posterior - piriformis
Floor - levator ani + coccygeus
What nerve network lies on piriformis (posterior wall of pelvis)
Sacral plexus
What are the 3 parts of levator ani + collective functions of the levator ani
Puborectalis
Pubococcygeus
Iliococcygeus
Support abdominopelvic organs and maintain faecal + urinary continence
2 functions of the pelvic floor
Support the abdominopelvic organs
Urinary + faecal incontinence
Innervation of pelvic floor
Sacral plexus
Define a
- cystocele
- rectocele
Cystocele - prolapse of bladder into vagina (anterior prolapse)
Rectocele - prolapse of anterior wall of rectum into posterior wall of vagina (posterior prolapse)
How does childbirth injure pelvic floor
Weakens levator ani and pelvic fascia due to stretching and can also alter position of bladder neck and urethra leading to urinary incontinence
Why may an episiotomy (incision of the perineum and the posterior vaginal wall) be done during childbirth
To enlarge vaginal opening so baby can come out easier + prevent severe tear of perineum
Major arterial supply to the pelvis is from branches of which arteries
Branches of the right and left internal iliac artery
Main artery supplying the perineum
Internal pudendal (branch of internal iliac)
Which branch of the internal iliac supplies some of the pelvic muscles, ilium and head of femur
Obturator artery
Which branches of the internal iliac supplies the seminal glands, prostate + rectum
Middle + inferior rectal
Which branch of the uterine artery supplies the vagina and base of bladder
Vaginal artery
Which branch of the internal iliac supplies the uterus
Uterine artery
Which branches of the abdominal aorta supply the testes/ovaries
Gonadal artery (testicular and ovarian respectively)
Which part of the rectum drains into the portal circulation
Upper 2/3 –> superior mesenteric vein –> liver
Which part of the rectum drains into the systemic circulation
Lower 1/3 –> middle rectal vein –> IVC
Why may haemorrhoids be associated with liver cirrhosis
Liver cirrhosis increases portal pressure so venous drainage won’t be as efficient therefore leading to swollen engorged veins in the rectum –> haemorrhoids
Which venous plexus does the prostatic venous plexus communicate with on its posterior surface
What is the significance of this
Vertebral venous plexus
Route of bone metastasis in prostate cancer as the prostatic venous plexus drains into the internal iliac vein which connects with the vertebral venous plexus
Ilioinguinal nerve provides somatic innervation to what in males/females (only want sensory answer, not motor)
Sensation to
- Anteromedial thigh
- Males - skin over root of penis
- Females - labia majora
Genitofemoral nerve has 2 branches - genital branch and femoral branch
What does each branch supply
Genital branch - motor to cremaster muscle and provides sensation to anterior scrotal skin
Femoral branch - sensation to medial surface of superior thigh
Clinical significance of the genitofemoral nerve
Cremasteric reflex - contraction of the cremaster muscle when medial surface of superior thigh touched because their nerve supplies are connected
Pudendal nerve arises from plexus what and has what nerve roots
Sacral plexus
S2-4
Bony landmarks for pudendal nerve when performing a pudendal nerve block during labour
Ischial spines
Pudendal nerve descends from sacral plexus and leaves the pelvis through the greater sciatic foramen, crosses sacrospinous ligament then re-enters pelvis via lesser sciatic foramen
After re-entering the pelvis, it accompanies the internal pudendal artery and vein through what canal
Pudendal canal (also known as Alcock’s canal – a structure formed by the fascia of the obturator internus muscle)
Pudendal nerve innervates what (motor + sensory)
Motor
- levator ani
- bulbospongiosus
- ischiocavernosus
- external urethral sphincter
Sensory
- skin of external genitalia
- skin of perineum
- peri-anal skin
Sympathetic innervation of the pelvis arises from what plexus
Superior hypogastric plexus (Sacral splanchnic nerves)
Parasympathetic innervation of the pelvis arises
S2-S4 nerves (pelvic splanchnic nerves)
4 primary lymph nodes in the pelvis receiving drainage of the pelvic organs
External iliac
Internal iliac
Sacral
Common iliac
External iliac lymph nodes receive lymph from
Inguinal lymph nodes - MAINLY
Middle/anterior pelvic organs - external genitalia, vagina, cervix, uterus
Internal iliac lymph nodes receive lymph from
Inferior pelvic organs - e.g. prostate
Gluteal region
Deep perineum
Sacral lymph nodes receive lymph from
Posteroinferior pelvic organs
Components of the male genital (external + internal)
External
- penis
- urethra
- scrotum
Internal
- testes
- epididymis
- vas deferens
- seminal vesicles
- prostate
- bulbourethral glands
In males, the gonads (testes) are located outside the abdominopelvic cavity but remain connected to the structures located within the abdominopelvic cavity
Why is this?
To keep temperature optimal for sperm production as scrotum are a cooler temp which enzymes of spermatogenesis work better at
Inguinal canal carries the spermatic cord
What are the main contents of the spermatic cord
Blood vessels - testicular artery, cremasteric a + v
Nerves - genitofemoral nerve
Vas deferens
Lymph vessels
Outer fibrous layer of the testes
Tunica albuginea
What is the peritoneal sac covering the testes called (covers the tunica albuginea)
+ what are the 2 layers of it
Tunica vaginalis
Visceral and parietal layer
What material is present between the 2 layers of the tunica vaginalis
Serous fluid
What is a hydrocele and haemtocele
Collection of serous fluid or blood respectively in the cavity of the tunica vaginalis
Arterial supply of testes
Testicular arteries - L2
The testicular arteries travel retroperitoneally and cross what 2 structures near the pelvic brim
Ureter
External iliac artery
Venous drainage of testes is via what plexus
Pampiniform plexus
Function of the pampiniform plexus
Part of thermoregulatory system to keep testes at a constant temp
Right testicular vein drains into
Left testicular vein drains into
IVC
Left renal vein
What is a varicocele
Swelling of the veins of the pampiniform plexus
Testes lymphatic drainage (2)
Lumbar
Para-aortic
Function of vas deferens
Carries sperm from the epididymis to the seminal vesicles, when it joins the duct of the seminal vesicles it becomes the ejaculatory duct
Pathway of sperm production
Produced by testes –> travels to epididymis to mature –> carried by vas deferens to seminal vesicles where the ejaculatory duct is formed –> prostatic urethra –> membranous urethra –> further secretions added by bulbourethral glands into penile urethra
Bulbourethral glands empty their secretions into which part of the urethra
Penile/spongy
Prostate lymphatic drainage (1)
Internal iliac nodes
Seminal vesicle lymphatic drainage (2)
External + internal iliac nodes
Scrotum lymphatic drainage (1)
Superficial inguinal nodes
Penis lymphatic drainage (2)
Superficial + deep inguinal nodes
Special feature in the histology of testes
Interstitial Leydig cells between tubules - produce testosterone
Special feature in the histology of prostate
Eosinophilic masses called corpora amylacea in older men
Majority of the male genital tract is lined by what epithelium
Pseudostratified columnar
Contents of lesser sciatic foramen (3)
Pudendal nerve
Internal pudendal artery + vein
Obturator internus
Contents of greater sciatic foramen (formed by sacrotuberous and sacrospinous ligaments)
- nerves
- vessels
- muscles
Nerves - sciatic, superior/inferior gluteal, pudendal and others
Vessels - superior/inferior gluteal a + v, internal pudenal a + v
Piriformis - separates it into 2 halves
