Anatomy Flashcards
What is the pelvis?
Space bound by pelvic girdle
What is the great pelvis?
Upper abdo region of pelvic girdle, above pelvic inlet
What is the lesser pelvis?
Lower region of pelvic girdle, below pelvic inlet
Pelvic cavity and perineum
What is the pelvic cavity?
Region between inlet and pelvic floor
What is the perineum?
Region below the pelvic floor
What are differences between the male and female pelvis?
Female pelvic girdle is wider, thinner boned and has an approximately cylindrical cavity
Pubic arch in female is wider
What term describes the normal desirable shape of the pelvis?
Gynecoid
What term describes a female pelvis which is shaped more like a males?
Android
What is an anthropoid pelvis?
Anterior posterior distance much greater than the transverse
What is a platypelloid pelvis linked with?
Rickets
What measurements can be taken to determine whether a birth canal is the correct dimensions to permit birth?
Diagonal conjugate = (>12 cm) measured by vaginal exam
True Conjugate = (Diagonal conjugate – Pubic symphysis depth =10.5-11.0cm)
Intertuberous distance = (>12cm)
Interspinous distance = (>11cm)
Describe the plane of pelvic orientation
~60º
ASIS aligns with PT in vertical plane
Which direction do the urogenital and anal triangles face?
Anal triangle faces postero-inferiorly
Urogenital triangle faces inferiorly
What does the perineum contain?
External genitalia and distal anal canal
What are the female parts of external genitalia?
Labia (Majora & Minora)
Crura of clitoris
Bulb of vestibule
Greater vestibular gland
What are the male parts of the external genitalia?
Crura & bulb of penis Urethra Testes (hanging from abdo wall) Scrotum Bulbourethral gland
What neurovascular structures do both male and female perineum contain?
Internal pudendal artery (& branches)
Pudendal nerve (& branches)
Perineal membrane
What is the pelvic floor?
Bowl-shaped group of sheet-like muscles that support pelvic viscera & assist with sphincters
What muscles make up the Levator Ani?
Iliococcygeus
Pubococcygeus
Puborectalis
What is the function of Puborectalis?
Maintains angle at anorectal junction to help in faecal continence
Loss of angle leads to increased risk of faecal incontinence
What is the Perineal body?
Only point of union between pelvic floor and perineal membrane
Important for integrity of pelvic floor
Support to posterior vaginal wall
Attachment point for anal sphincter
What is the nerve supply to levator ani?
S4
What are the borders of the Urogenital Triangle?
Ischial tuberosities to pubic symphysis
What are the borders of the anal triangle?
Ischial tuberosities to coccyx
What are female external genitalia?
Folds of skin guarding the vagina and clitoris
Where do the greater vestibular glands lie in the female? And what do they do?
Drain into vestibule at 5 & 7o’clock
Secrete lubricant
What is an Episiotomy?
Create a controlled increase in aperture size during childbirth to give a controlled tear
What types of incision can be used for an episiotomy?
Midline incision
Media lateral incision
What is the clitoris?
Erectile body very similar in structure to the penis
What is the male equivalent to the bulb of vestibule?
Corpus spongiosum of penis
What are the female equivalents to the bulbourethral glands?
Greater vestibular glands
What is the sensory innervation of the glans of the clitoris and penis?
Pudendal nerve S2-4
What does the Female reproductive tract connect the outside world to?
The peritoneal cavity
What are the 3 parts of the uterine tubes?
Infundibulum
Ampulla
Isthmus
What is the cervical canal?
Connects vagina and uterine cavity via the external and internal os
What can be used to directly view the uterine cavity?
Hysteroscopy
What can be used to determine whether there is a blockage in the uterine tubes?
Hysterosalpingogram - dye into cavity
What presents a route of infection spread by an STI?
Uterine tubes can allow spread from vagina
What is an ectopic pregnancy?
Blastocyst implantation can occur into most tissues and development will continue if a placenta is established
How might a tubal ectopic present?
6-8 weeks, pain
Rupture of tube can lead to peritonitis
What is normal nulliparous size for a uterus?
Approx 80x50x30mm HxWxD
What is the pelvic girdle?
Bony pelvis
What tool can be used to view the cervix?
Speculum
What are the fornices?
Superior portions of vagina extending into recess created by vaginal portion of the cervix
What tissue type are the ovaries derived from?
Intermediate mesoderm
What is the blood supply to the ovary?
Ovarian artery
Branch of the aorta at L2
Where do the ovaries sit? And what are they suspended in?
Sit close to lateral pelvic wall suspended in broad ligament
What is the ovary covered in? And what goes through this layer?
Covered in peritoneum which forms surface epithelium (germinal layer) covering
Ovulation takes place through this layer and into peritoneal cavity
What is the round ligament of the ovary similar to in males?
Gubernaculum
What could Ovulation/cysts/tumour impinge on?
Obturator nerve (L2-4)
Resulting in pain/ache in medial thigh, hip or knee; medial thigh
weakness/wasting
What is the blood supply to the uterus and vagina? And where do they pass?
Uterine: branch of internal iliac, Heads toward lateral cervix and fornix, Passes superior to ureter
Ovarian: From aorta at L2
Vaginal: Often a branch of the uterine, Can arise independently from internal iliac
Where does the ureter pass in relation to the uterine artery? And what is the significance of this?
Passes inferior to uterine artery (water under bridge)
Very delicate and must not be ligated, crushed or moved too much
Why can cervical cancer cause kidney failure?
Compression/obstruction of ureters as they run in close proximity to cervix
Where do Uterine & cervical lymphatics drain?
Pass to external, internal iliac & sacral nodes
Some go to palpable inguinal nodes via round ligament
What is a hysterectomy?
Removal of uterine body alone – cervix preserved
What is a Bilateral salpingo- oophorectomy?
Removal of tubes & ovaries
What is a radical hysterectomy?
Removal of everything including lymphactics
Distal vagina normally preserved
What is a normal position of a uterus and what supports it?
Anteverted anteflexed
Rests on bladder and is supported by it in this position
What is the angle of anteversion?
Between vagina and cervical canal
What is the angle of anteflexion?
Between cervical canal and uterus
Which position of the uterus carries the highest risk of prolapse?
Retroverted retroflexed
How can you estimate the size and position of the uterus?
Bimanual palpation
Vaginal exam with other hand on abdomen
What is the round ligament of the uterus?
Equivalent to male gubernaculum
Route for uterine lymphatic drainage to superficial inguinal nodes (palpable)
What does peritoneum cover in the pelvic region of a female?
Bladder, uterus, cervix and upper rectum
What is the folded peritoneum region between bladder and uterus called?
Vesico uterine pouch
What is the folded peritoneum pouch between the uterus and the rectum called? And what clinical significance does it have?
Recto uterine pouch (pouch of Douglas)
Relevant to infected fluid accumulation
Abscess & fistula formation
Home abortion – line of travel of inserted implements
What is the broad ligament?
Large double layered fold of peritoneum
What are the different parts of the round ligament?
Mesovarium
Mesosalpinx
Mesometrium
Where does the round ligament travel?
Passes through Inguinal canal and into labia majora
Where does ovulation take place?
Ovulation takes places through peritoneal covering
Germinal epithelium
What are the layers of pelvic fascia?
Visceral (covers organs)
Parietal (covers muscles & walls)
Endopelvic: Loose & fatty (fills spaces), Dense & fibrous (supportive ligaments)
What comes together at the tendinous arch?
Dense pelvic fascia
What ligament supports the cervix/uterus?
Cardinal ligament
What ligament supports the bladder?
Lateral ligament of the bladder
What ligament supports the rectum?
Lateral ligament of the rectum
Where does the tendinous arch run?
From pubis to sacrum
What is the Paracolpium?
Connection of vaginal fascia to tendinous arch
Important for support
What do uterine tubes develop from?
Paired paramesonephric ducts
What can Uterine & vaginal malformations lead to?
1° amenorrhoea, infertility or problematic pregnancy
Visceral sensory fibres from the uterus travel to the CNS via two different routes. What are they?
Pelvic organs above pelvic pain line covered in peritoneum Refer pain to T10-L1 (via Sympathetic nerves)
Pelvic organs not covered in peritoneum below pelvic pain line Refer pain to S2-4 (via Parasympathetic nerves)
Describe uterine innervation
Sensory Neurons above pelvic pain line run with Sympathetics (T10-T12)
Sensory Neurons below pelvic pain line run with Parasympathetics (S2-4)
Somatic sensory innervation to distal vagina (S2-4 Pudendal nerve)
How would you anaesthetise the uterus above the pelvic pain line?
Spinal Block @ L3/4 (inject into CSF)
& an epidural at the same level
(Combined spinal epidural – CES/CSE)
How would you anaesthetise the uterus below the pelvic pain line?
Caudal epidural (sacral hiatus & canal)
How would you anaesthetise the distal vagina?
Pudendal Nerve Block
Palpate ischial spine and inject around it via vaginal wall
What structures will be anaesthetised by a pudendal nerve block?
Perineum, distal vagina & anal canal
What is the testicle a derivative of?
Intermediate mesoderm
Where does the testicle lymph drainage go to?
Para-aortic nodes ~L2
What structure aids the descent of the testicle through the inguinal canal?
Gubernaculum
What is the path of sperm from their site of production?
Produced in seminiferous tubules Into Rete testis Head of epididymis Body Tail Ductus deferens
What is a hydrocele?
Excess fluid in tunica vaginalis
What is a spermatocoele?
Swelling of epididymis
What is the Processus vaginalis?
Fold of parietal peritoneum
Future site of inguinal canal
What forms a potential weak spot and is the route taken by indirect inguinal hernias?
Processus vaginalis
Which layer of the abdo wall doesn’t contribute to the spermatic coverings?
Transversus abdominis
What forms the tunica vaginalis?
Lower part of processus vaginalis
Describe the Content of the spermatic cord
- Pampiniform plexus
- Ductus deferens
- Lymphatics
- Testicular artery
- Ductus deferens artery
- Cremasteric artery
- Genital nerve
- Autonomic nerves
- (Ilioinguinal nerve)
Describe the coverings of the spermatic cord
Internal spermatic fascia Cremasteric fascia External spermatic fascia Colles fascia Dartos fascia Skin