Surgical anatomy of the female pelvis — structured oral station (12 minutes)

Opening prompt — "Construct your dissection plan for this patient."

Model response — say it in this order:

• "This patient has two specific risk factors: a 10-week bulky fibroid uterus and one previous lower-segment Caesarean section. Both alter the dissection anatomy — the fibroid displaces the ureter laterally and the prior Caesarean section makes the bladder adherent to the lower uterine segment."
• "I would plan a total laparoscopic hysterectomy in the standard anatomical sequence: identify the ureter at the pelvic brim first, divide the round ligament, open the pararectal and paravesical spaces, skeletonise the ureter down to the uterine artery, divide the uterine artery at its origin from the internal iliac, develop the bladder flap with sharp dissection for the prior Caesarean section, divide the utero-ovarian ligaments, divide the uterosacral ligaments, perform the colpotomy along the Koh cup, retrieve the specimen, and close the cuff with a continuous barbed suture or interrupted figure-of-eight absorbable sutures."
• "I would check the pre-operative checklist: anaesthetic depth, full muscle relaxation, NG tube, urinary catheter, patient in steep Trendelenburg, the team briefed on the steps and the named complications."
• "I would quote the named evidence for the route: the Cochrane Pickett 2023 review (PMID 37642285) — vaginal route preferred to abdominal when feasible, laparoscopic advantages over abdominal with shorter recovery but higher urinary tract injury (OR 2.16, 95% CI 1.19–3.93)."^[7]

Examiner is listening for: named spaces, named sequence, named vessels and nerves, named complications.

Probe 1 — "Name the five retroperitoneal avascular spaces and their boundaries."

• "The five retroperitoneal avascular spaces of the pelvis are: pararectal, paravesical, retropubic Retzius, presacral (retrorectal), and rectovaginal."
• "The pararectal space is divided into the Latzko (lateral, between internal iliac artery and ureter) and the Okabayashi (medial, between ureter and rectum) compartments."
• "The paravesical space is bounded medially by the bladder and the obliterated umbilical artery, laterally by the obturator internus, posteriorly by the cardinal ligament."
• "The Retzius space is between the pubic symphysis and the bladder, opened for colposuspension and Burch procedures."
• "The presacral space is between the rectum and the sacrum, opened for sacrocolpopexy and presacral neurectomy."
• "The rectovaginal space is between the rectum and the vagina, opened for posterior colpotomy and rectovaginal endometriosis excision."^[1]

Probe 2 — "Trace the ureter along its pelvic course and name the most common site of injury."

• "The ureter crosses the pelvic brim over the bifurcation of the common iliac artery. It runs along the medial leaf of the broad ligament peritoneum, passes under the uterine artery at the internal os 1.5–2 cm lateral to the cervix — this is the 'water under the bridge' and the most common site of injury. It then traverses the cardinal ligament to enter the bladder."
• "The Kobayashi 2023 case series (PMID 37638335) documents the lateral cervical step as the most common site of injury. The Cochrane Pickett 2023 review (PMID 37642285) found a higher urinary tract injury rate with laparoscopic hysterectomy than abdominal (OR 2.16, 95% CI 1.19–3.93)."^[6][7]

Probe 3 — "Name the pelvic autonomic nerves and the three named zones of injury at hysterectomy."

• "Sympathetic fibres from T10–L2 form the superior hypogastric plexus on the aortic bifurcation and descend as the two hypogastric nerves. Parasympathetic fibres from S2–S4 emerge from the sacral foramina over the piriformis as the pelvic splanchnic nerves. The two systems join on the lateral side of the mesorectum and the base of the broad ligament to form the inferior hypogastric (pelvic) plexus, with three named subdivisions — vesical, uterovaginal, rectal."
• "The three named zones of injury are: presacral (where the hypogastric nerves descend over the sacral promontory), lateral parametrial (where the pelvic splanchnic nerves cross the cardinal ligament), and uterosacral (where the inferior hypogastric plexus runs to the uterus)."
• "The Sakuragi 2021 nerve-sparing radical hysterectomy (PMID 35111930, Okabayashi–Kobayashi method) describes the systematic preservation of these nerves."^[4][1]

Probe 4 — "At the lateral cervical step, brisk bleeding is encountered from the tissue crossing over the right ureter. What do you do?"

• "The most likely source is the lateral cervical branch of the uterine artery crossing over the ureter — the named source of bleeding at this step."
• "I would stop, apply pressure with a swab, do not blind-diathermy near the ureter, and identify the vessel exactly."
• "I would suture-ligate the vessel with a fine absorbable suture (4-0 or 5-0 PDS) or apply a clip; bipolar diathermy is acceptable if the ureter is identified and away from the field; never use unipolar diathermy near the ureter."
• "At the end of the case, intra-operative cystoscopy with indigo carmine and furosemide to demonstrate bilateral ureteric efflux; check postoperative creatinine on day 2."
• "If haemostasis cannot be secured, convert to laparotomy — the consultant-level response."^[1][6]

Probe 5 — "The case proceeds to the colpotomy. The bladder has been mobilised and the uterine vessels divided. What are you thinking about as you perform the colpotomy?"

• "The colpotomy is performed circumferentially along the Koh cup or the vaginal tube, above the level of the uterosacral ligaments and below the level of the uterine artery division."
• "I am thinking about three things: the position of the ureter (which should be safely lateral at this point), the position of the rectum (posteriorly — do not buttonhole the rectum with the posterior colpotomy incision), and the integrity of the bladder flap (which has been mobilised down to the upper vagina)."
• "After the colpotomy, the specimen is retrieved vaginally if the uterus is small enough, or by morcellation in a containment bag if required — AAGL morcellation practice report 2014 (PMID 24865630)."^[8][1]
• "Cuff closure is with continuous barbed suture (V-Loc or Stratafix) or interrupted figure-of-eight absorbable suture (e.g. 0 Vicryl). The cuff closure technique determines the dehiscence rate."

Probe 6 — "The patient wakes up well and you go to see her on ward next morning. She asks what happened and whether she is safe to go home tomorrow."

This is a scored domain, not a courtesy. Demonstrate it out loud:

• Move to her eye level, use her name, brief plainly: "The operation went well. We removed the uterus laparoscopically through four small cuts on your tummy. The surgery took a few hours and we were able to preserve your ovaries. You have a small cut at the top of the vagina where we closed the cervix, and there are some stitches there that will dissolve over the next few weeks. You should be safe to go home when you are eating and drinking, mobilising, and your pain is controlled with tablets. Most women go home the next day or the day after."
• Acknowledge any concerns, invite questions, offer written information, and tell her how to contact the team.
• Explain the warning signs: heavy vaginal bleeding, fever, worsening pelvic pain, inability to pass urine, or any concerns — contact the team immediately.
• Document the conversation and the plan.^[6]

Probe 7 — "What are your top three learning points from this case?"

• "Identify the ureter first, every time. The first step at laparoscopic hysterectomy is to find the ureter at the pelvic brim. If you cannot see it, open the pararectal space and trace it from above. Do not coagulate tissue you cannot identify."^[1]
• "The lateral cervical branch of the uterine artery is the named source of bleeding. Identify the vessel, control with suture or clip, do not blind-diathermy. Confirm ureteric integrity at the end of the case."^[6]
• "The three named zones of nerve injury are presacral, lateral parametrial, uterosacral. Identify and preserve these nerves at every hysterectomy. Bilateral injury produces bladder dysfunction."^[4]