Anatomy Flashcards
What is the homologous structure of bulbourethral glands in females?
Bartholin’s glands
The appendices artery is a branch of what?
Ileocolic artery (branch of
Posterior caecal artery)
What vessel does the ureter cross and where?
It crosses beneath the uterine artery- 2cm superior to the ischial spine (water under the bridge), at the level of the internal Os
Nerve supply of area around EAS
Inferior anal nerve
Most common nerve to be damaged in sacrospinous fixation?
Pudendal nerve (runs beneath sacrospinous ligament)
Symptoms: neuralgia over perineum
Lowest level of dermatomal block to abolish pain from uterus
Sympathetic nerve supply to uterus is by which spinal nerves
T10
T10/11/23 and L1 (inferior hypogastric plexus)
Obturator nerve root
L2-L4
Supplies adductor region of thigh
Dermatome: transverse suprapubic incision at CS
L1
Layers to reach epidural space and level usually done at
Skin, subcutaneous fat, supraspinous ligament, interspinous ligament and ligamentum flavum
L3/4
Difference between spinal and epidural
Spinal- anaesthetic injected directly into the dural sac contacting CSF
Epidural = just epidural space
Types of FGM
type 1: part or total removal of the clitoris or clitoral hood
type 2: part or total removal of the clitoris and the labia minor
type 3: narrowing of the vaginal opening
type 4: all other harmful procedures to the female genitalia for non-medical purposes
Nerve that passes anterior to the psoas major muscle
Genitofemoral nerve
Nerve supply of cervix
Pelvic splanchnic (S2-4)- extension of inferior hypogastric plexus
Tortuous glands in endometrium following ovulation- type of endometrium?
Secretory
Sacroiliac joint type
Synovial
Nerve route (origin) of iliohypogastric and ilioinguinal nerve
L1- lumbar plexus
Borders of lesser sciatic foramen
Structures that pass through lesser sciatic foramen?
Borders:
Superior – sacrospinous ligament and ischial spine
Anterior – ischial spine, lesser sciatic notch and ischial tuberosity
Posterior – sacrotuberous ligament
Internal pudendal artery and vein
Pudendal nerve (first leaves the pelvis via the greater sciatic foramen, and then re-enters via the lesser sciatic foramen)
Obturator internus tendon
Nerve to obturator internus
What does the ductus venosus connect?
Umbilical vein and IVC (oxygenated blood)
Nerve supply to bladder
Neurological control is complex, with the bladder receiving input from both the autonomic (sympathetic and parasympathetic) and somatic arms of the nervous system:
Sympathetic – hypogastric nerve (T12 – L2): causes relaxation of the detrusor muscle, promoting urine retention.
Parasympathetic – pelvic nerve (S2-S4): causes contraction of the detrusor muscle, stimulating micturition.
Somatic – pudendal nerve (S2-4): innervates the external urethral sphincter, providing voluntary control over micturition.
In addition to the efferent nerves supplying the bladder, there are sensory (afferent) nerves that report to the brain. They are found in the bladder wall and signal the need to urinate when the bladder becomes full.
Sympathetic = storage
Parasympathetic = Peeing
Contents of the inguinal canal
Spermatic cord (biological males only)
Round ligament (biological females only)
Ilioinguinal nerve –
Note: only travels through part of the inguinal canal, exiting via the superficial inguinal ring (it does not pass through the deep inguinal ring)
This is the nerve most at risk of damage during an inguinal hernia repair.
Genital branch of the genitofemoral nerve
Ligament arising from lateral border of cervix and attached to end-pelvic fascia?
Cardinal ligament
Dorsal nerve of clitoris is a terminal branch of which nerve?
Pudendal nerve
Path of lateral cutaneous nerve of thigh (lateral femoral cutaneous nerve)
Passes through psoas major muscle, and emerges from its lateral border, crosses the iliacus muscle obliquely, toward the anterior superior iliac spine (ASIS).
It is crossed by the deep circumflex iliac artery and the deep circumflex iliac vein.
It enters the thigh by passing beneath (the lateral part of) the inguinal ligament in the muscular lacuna, or through (the lateral part of) the inguinal ligament itself.
It then passes over the sartorius muscle, travelling from medial to lateral.
Coeliac trunk/ SMA/ IMA- at what level does each branch from aorta?
CT- T12/L1
SMA- L1
IMA- L3
Main blood supply to transverse colon?
Middle colic artery
Sutures enclosing largest fontanelle?
Frontal (metopic), coronal, sagittal
Pelvic measurements: transverse/ oblique/anteroposterior at inlet/mid-cavity and outlet
Transverse:
Inlet: 12.7cm
Mid: 11.5cm
Outlet: 10cm (distance between ischial tuberosities)
Oblique:
Inlet: 11.5cm (Iliopectineal eminence to opposite SI joint)
Mid: 11.5cm (lower SI joint to midpoint of obturator membrane)
Outlet: 11.5cm
Anteroposterior:
Inlet: 10cm (sacral prominently - Symphysis pubis)
Mid: 11.5cm (S3 to midpoint of pubic symphysis)
Outlet: 12.7cm (pubis to sacrococcygeal joint)
Fetus born with absence of mastoid process (or poorly developed). Which structure is at increased risk of damage during delivery?
Facial nerve (CN VII)
Scarpa’s/ Dartos/ Colles fascia
Scarpa’s = deep membranous layer of the superficial fascia of the abdomen (deep to Camper’s)
Dartos fascia = scarpas that extends superficially to the spermatic cord and scrotum
Colles fascia = continuation of darts fascia as it blends with deeper layers of peritoneum
Muscle of pelvic floor not inserted into the perineal body?
Coccygeus
Pelvic floor muscles
Levator ani (puborectalis, pubococcygeus and iliococcygeus), coccygeus
Contents of the deep perineal pouch
Muscles:
- Deep transverse perineal muscle
- External urethral sphincter
- Compressor urethrae muscle (females)
- Urethrovaginal sphincter (females)
- Internal pudendal vessel
- Dorsal nerve of clitoris
Other:
Membranous portion of urethra (males)
Proximal portion of urethra (females)
Bulbourethral gland (males)
What is the deep perineal pouch and what are its inferior and superior borders?
The space between superior and inferior layers of the urogenital diaphragm
Inferior border = perineal membrane
Superior border = superior fascia of urogenital diaphragm
Obturator nerve: obstetric cause of entrapment and sensory/ motor loss.
Compression between head of foetus and bony structures of pelvis
Sensory: upper medial thigh
Motor: weakness leg adduction
Common peroneal nerve: obstetric cause of entrapment and sensory/ motor loss.
Compression lateral head of fibula and leg bars (lithotomy position)
Sensory: foot and anterolateral leg
Motor: ‘foot drop’, loss of anterior compartment extensors
Lateral femoral cutaneous nerve: obstetric cause of entrapment and sensory/ motor loss.
Obstetric cause: pregnancy
Sensory: lateral thigh
Motor: nil
Femoral nerve: obstetric cause of entrapment and sensory/ motor loss.
Pressure from a foetus in a difficult birth
Sensory: anterior thigh and knee
Motor: Quadriceps (SLR) weakness, loss of knee jerk
Internal/ external anal sphincter innervation
Internal (above dentate line):
- Sympathetic contraction
- PS relaxation
- Pelvic splanchnic nerves (S4) via inferior hypogastric plexus
- Sensitive to stretch
External (below dentate line):
- Innervation via inferior rectal branch of pudendal nerve and perineal branch of S4
Where is the hypothalamus located in the brain?
Diencephalon
Where is the pituitary located?
Pea-sized and protrudes from end of hypothalamus. Sits in a bony cavity called the sella turcica (part of the sphenoid bone) in the middle cranial fossa