AN48.1-8 | Pelvic wall and viscera — Summary & Reflection

REFLECT

A 38-year-old woman presents with a 6-month history of pelvic pain and heavy menstrual bleeding. Transvaginal ultrasound shows a 6 cm fibroid in the posterior wall of the uterus. She undergoes a total abdominal hysterectomy.

What are the key anatomical steps in a total abdominal hysterectomy? At what point is the ureter at greatest risk, and why? Which ligament provides the main support to the uterus and must be divided? If the fibroid was in the broad ligament, which structures would be at risk during its removal?

KEY TAKEAWAYS

Pelvic Wall and Viscera — Key Points:

1. Pelvic diaphragm: levator ani (pubococcygeus, puborectalis, iliococcygeus) + coccygeus; supports pelvic viscera; puborectalis maintains the anorectal angle
2. Internal iliac artery: posterior division (iliolumbar, lateral sacral, superior gluteal); anterior division (obturator, inferior gluteal, superior + inferior vesical, uterine, internal pudendal, middle rectal)
3. Uterine artery crosses ureter 2 cm lateral to cervix ("water under the bridge")
4. Sacral plexus: L4–S4; gives sciatic, pudendal, superior + inferior gluteal; pelvic splanchnics (S2–S4) = parasympathetic to pelvic viscera
5. BPH: transition zone → compresses urethra; PCa: peripheral zone → hard nodule on DRE
6. Automatic bladder: lesion above S2 → spastic/reflex bladder; autonomous bladder: lesion at/below S2 → atonic/overflow
7. Suprapubic cystostomy: full bladder rises extraperitoneally above pubis → safe midline entry
8. Haemorrhoids: internal (above pectinate line = painless); external (below = painful)
9. Ectopic pregnancy: blood in pouch of Douglas → posterior fornix tenderness
10. Structures on DRE: prostate, seminal vesicles (male); cervix, pouch of Douglas (female)