POP-Q Classification for Uterovaginal Prolapse

The Core Concept: The Hymen as Reference Zero

• Above the hymen (normal/reduced) = negative number (e.g., -3 cm)
• At the hymen = 0
• Below the hymen (prolapsing out) = positive number (e.g., +2 cm)

The 9 Measurements

The Anatomical Diagram

6 Vaginal Points (Measured at Valsalva)

Anterior Compartment

• In a normal woman: Ba = Aa = -3 cm
• In full vaginal eversion: Ba = +tvl

Middle / Apical Compartment

• The difference between C and D helps differentiate true uterine descent (C and D descend together) from cervical elongation (C descends, D stays high).

Posterior Compartment

3 Anatomical Landmarks (NOT measured at Valsalva)

How to Record / Write Down the POP-Q

Method 1: The Tic-Tac-Toe Grid (Standard Format)

 Aa   |  Ba  |  C
------+------+------
 gh   |  pb  | tvl
------+------+------
 Ap   |  Bp  |  D

 -3   |  -3  |  -8
------+------+------
  3   |   3  |   9
------+------+------
 -3   |  -3  |  -9

 +2   |  +4  |  -5
------+------+------
  4   |   3  |   8
------+------+------
 -3   |  -3  |  -5

Method 2: Linear Notation

The 5 Stages of POP-Q (Staging Criteria)

The leading edge is whichever single point has the most positive (most prolapsed) value. That point alone determines the stage.

Important Points and Clinical Pearls

1. After hysterectomy: Point D is omitted. Point C represents the vaginal cuff, and Ba = Bp = -3 if no prolapse.
2. C vs D differentiation: If C descends significantly but D remains high, this suggests cervical elongation rather than true uterine descent. This is clinically relevant for surgical planning.
3. Aa and Ap are fixed points (always between -3 and +3). Ba and Bp are variable and move with prolapse - they are the "leading edge" markers for each compartment.
4. Naming the prolapse in POP-Q terminology: Rather than saying "cystocele," POP-Q describes which points are abnormal (e.g., "anterior wall prolapse with Ba +4").
5. How to identify which compartment is most affected:
   • Anterior prolapse (cystocele): Ba is the most positive point
   • Apical prolapse: C or D is most positive
   • Posterior prolapse (rectocele): Bp is most positive
6. Worked example - posterior predominant prolapse (from PMC3056425):
   • Bp = +5, Ap = +2, vaginal cuff C = -6, tvl = 8
   • Leading edge = Bp = +5; since +5 > +1 and < +(8-2) = +6, this is Stage III Bp prolapse

Summary: Quick Reference Card

9 measurements = 6 vaginal points + 3 landmarks

ANTERIOR:  Aa (fixed, -3 to +3) | Ba (variable, leading anterior edge)
APICAL:    C (cervix/cuff)       | D (posterior fornix; omit post-hysterectomy)
POSTERIOR: Ap (fixed, -3 to +3) | Bp (variable, leading posterior edge)
LANDMARKS: gh | pb | tvl (not at Valsalva)

Grid format:
 Aa  | Ba  | C
 gh  | pb  | tvl
 Ap  | Bp  | D

Staging: based on most positive single measurement (leading edge)
 Stage 0: all points normal
 Stage I:  leading edge < -1 cm
 Stage II: leading edge -1 to +1 cm
 Stage III: leading edge > +1 cm but < (tvl-2) cm
 Stage IV: leading edge ≥ (tvl-2) cm

Surgery for Uterovaginal (UV) Prolapse

Overview: Compartment-Based Approach

1. Anterior Compartment - Anterior Colporrhaphy (Anterior Vaginal Wall Repair)

1. Patient in lithotomy position; catheterise bladder.
2. Inject dilute adrenaline solution under anterior vaginal wall to hydrodissect.
3. Vertical midline incision on anterior vaginal wall from just below the urethral meatus to the cervix/vault.
4. Dissect the vaginal epithelium laterally off the pubocervical fascia using sharp/blunt dissection.
5. Identify the fascial edges and plicate them in the midline using interrupted or continuous absorbable sutures (2-0 Vicryl), reducing the bladder neck and bladder.
6. Trim excess vaginal epithelium.
7. Close vaginal skin with a continuous absorbable suture.

Note on mesh: Mesh-augmented anterior repair had higher short-term anatomical success but carries significant risks (pain, erosion, dyspareunia) and is restricted in the UK. Current standard is native tissue repair.

2. Apical Compartment Procedures

A. Vaginal Hysterectomy (with Pelvic Floor Repair)

1. Lithotomy position. Cervix grasped with Vulsellum forceps.
2. Circumferential incision around the cervix at the cervicovaginal junction (ring incision).
3. Anterior dissection: Bladder pushed upward; anterior peritoneum of the pouch of vesicouterine peritoneum opened.
4. Posterior dissection: Posterior vaginal wall opened; pouch of Douglas (posterior peritoneum) entered.
5. Clamping of ligaments (in sequence):
   • Uterosacral and cardinal ligaments (Mackenrodt ligaments) - clamped, cut, ligated bilaterally. These are the most important supports. The pedicles are later incorporated into the vault repair.
   • Broad ligament / uterine vessels - clamped, cut, ligated.
   • Cornual pedicles (round ligament, tube and ovarian ligament or infundibulopelvic ligament if oophorectomy required).
6. Uterus delivered and removed.
7. Vault closure and apical support: The vaginal vault is closed, incorporating the uterosacral-cardinal ligament pedicles into the angles of the vault closure to provide apical support. This is the McCall culdoplasty technique - placing sutures through the uterosacral ligaments and posterior vaginal wall to obliterate the pouch of Douglas and elevate the vault.
8. Anterior and/or posterior colporrhaphy + perineorrhaphy performed as needed.

B. Manchester (Fothergill) Repair - Uterus-Preserving

1. Anterior vaginal wall opened, bladder dissected upward.
2. Cardinal (transverse cervical) ligaments identified and divided on each side.
3. Cervical amputation at the level of internal os. The Sturmdorf suture is used to re-cover the raw cervical stump with vaginal skin (reduces stenosis).
4. The cut ends of the cardinal ligaments are sutured together anteriorly to the residual cervical stump - this is the Fothergill stitch - providing apical elevation.
5. Anterior colporrhaphy and posterior repair done as required.

C. Sacrospinous Ligament Fixation (SSLF)

1. Midline posterior vaginal incision; enter rectovaginal space by blunt dissection, pushing rectum medially.
2. Identify ischial spine; blunt dissection exposes the SSL.
3. Breisky-Navratil or Heaney retractors used for exposure.
4. Two non-absorbable sutures (e.g. PDS or Prolene) placed through the SSL approximately 1.5-2 fingerbreadths medial to the ischial spine - using a Capio suture device, Miyazaki hook, or Deschamps ligature carrier.
5. Sutures brought through the vaginal vault and tied, pulling the vault to the ligament ("pulley sutures" - delayed tying until other repairs complete).
6. Concomitant anterior and posterior colporrhaphy performed if needed.

D. Uterosacral Ligament Suspension (High Uterosacral Colpopexy)

1. Vaginal vault opened; peritoneum of pouch of Douglas entered.
2. Uterosacral ligaments identified on each side at the level of the ischial spine.
3. Permanent or delayed-absorbable sutures (2-3 per side) placed through uterosacral ligaments.
4. Sutures attached to the full thickness of the vaginal vault bilaterally.
5. Culdoplasty (McCall) performed to close the cul-de-sac.
6. Peritoneum closed; vault suspended.

E. Sacrocolpopexy (Abdominal/Laparoscopic/Robotic)

1. Patient in Trendelenburg; bowel retracted.
2. Retroperitoneal dissection to expose the sacral promontory (S1 level). Identify right ureter, middle sacral artery and vein.
3. Dissect vesicovaginal space anteriorly (between bladder and vagina) and rectovaginal space posteriorly.
4. Y-mesh: anterior arm sutured to anterior vaginal wall (2-3 cm below vault), posterior arm to posterior vaginal wall, trunk to the sacral promontory with permanent sutures (Prolene) or bone anchors.
5. Peritoneum closed over the mesh (retroperitonealise) to prevent bowel adhesions.
6. Concomitant Burch colposuspension or mid-urethral sling can be added for stress incontinence.

F. Sacrohysteropexy (Uterus-Preserving Abdominal Approach)

3. Posterior Compartment - Posterior Colporrhaphy + Perineorrhaphy

1. Allis forceps applied to posterior fourchette; triangular skin incision on perineum.
2. Midline vertical incision up the posterior vaginal wall to the vaginal apex.
3. Vaginal skin dissected laterally off the rectovaginal fascia.
4. Enterocele sac (if present) identified, opened, hernial sac contents reduced, neck ligated with a purse-string suture, sac excised.
5. Levator ani muscles approximated in the midline with interrupted absorbable sutures (levatorplasty) - note: over-aggressive levatorplasty causes dyspareunia.
6. Pubocervical / rectovaginal fascia plicated in the midline over the rectum.
7. Excess vaginal skin trimmed.
8. Perineal body reconstructed (perineorrhaphy) using interrupted sutures to rebuild the perineal body.
9. Vaginal skin and perineal skin closed.

4. Obliterative Procedures - Colpocleisis (Le Fort's Procedure)

1. Rectangular strips of vaginal epithelium removed from anterior and posterior vaginal walls.
2. Denuded anterior and posterior surfaces approximated with interrupted absorbable sutures, effectively closing off the vaginal canal while leaving lateral drainage channels for any cervical/uterine discharge.
3. Perineorrhaphy performed.

5. Mesh Considerations

• Chronic pelvic/vaginal/buttock pain
• Mesh erosion into vagina or bladder/rectum
• Dyspareunia
• Recurrent UTI and voiding dysfunction

6. Choice of Procedure - Summary

The Manchester (Fothergill) Repair - Detailed Account

History

What the Operation Does (Principle)

1. Cervical amputation - removes the elongated descending cervix
2. Cardinal ligament plication (Fothergill stitch) - shortens and reattaches the Mackenrodt/cardinal ligaments to the anterior surface of the cervical stump, elevating and retroverting the uterus into the pelvis
3. Anterior colporrhaphy + posterior colpoperineorrhaphy - repairs the associated cystocele and rectocele

Crucially, the peritoneal cavity is NOT entered - this reduces morbidity and operating time compared to vaginal hysterectomy.

Indications

1. Uterine prolapse with cervical elongation - the classic and best indication. The cervix is elongated but the uterine body has not descended much. The uterine sound on D&C will show the elongated canal.
2. Desire to preserve the uterus - women who want to retain the uterus but whose family is complete (relative - see below)
3. Preservation of reproductive function - in carefully selected younger women (though with significant obstetric caveats)
4. Elderly or unfit patients - the procedure avoids entering the peritoneal cavity, making it suitable for those not fit for hysterectomy

Contraindications

• Cervical or endometrial pathology (must be excluded preoperatively with colposcopy and endometrial sampling/hysteroscopy)
• Active cervical or pelvic infection
• Uterine body prolapse without cervical elongation (here vaginal hysterectomy is better)
• Undiagnosed uterine bleeding
• Severe cystocele or enterocele that cannot be corrected concomitantly

Pre-operative Assessment

• Full pelvic examination with POP-Q staging
• Cervical smear / colposcopy - mandatory to exclude cervical dysplasia/malignancy
• Endometrial sampling / hysteroscopy - to exclude endometrial pathology
• Uterine sound to measure the degree of cervical elongation
• Urodynamic studies if urinary symptoms coexist
• Thromboprophylaxis planning
• Bowel preparation (optional, centre-dependent)

Composite Steps of the Manchester Repair

Step 1 - Preliminary Dilatation and Curettage (D&C)

• The uterine sound gives accurate measurement of the degree of cervical elongation (length of cervical canal vs. total uterine length)
• Dilatation of the cervical canal facilitates passage of sutures through the canal later during the Sturmdorf/Bonney covering step
• Ensures adequate uterine drainage post-operatively and reduces risk of cervical stenosis
• Curettage provides endometrial tissue for histology - excludes malignancy

Step 2 - Amputation of the Cervix

• Anterior and posterior vaginal incisions are made circumferentially around the cervix at the cervicovaginal junction.
• The bladder is pushed superiorly off the anterior cervix using sharp/blunt dissection (identify the "tent of tissue" anteriorly and incise into the vesicovaginal space). A right-angle Heaney retractor elevates the bladder and ureter out of the field throughout.
• Posteriorly, the posterior cul-de-sac is explored digitally to ensure no bowel has prolapsed into it.

• The cervix is deviated to one side; the uterosacral and cardinal ligaments are identified laterally on each side.
• Each uterosacral ligament is clamped with a Heaney clamp placed immediately adjacent to the lower uterine segment (the clamp should grasp a small portion of the lower uterine segment), then incised and ligated with No. 1 or 2-0 synthetic absorbable suture (e.g. Vicryl). This is done bilaterally.
• Similarly, a small section of the cardinal ligament on each side is clamped, incised, and tied.
• Any enterocele sac found in the pouch of Douglas is identified, reduced, and repaired with a purse-string suture at this point before proceeding.

• With the bladder elevated anteriorly and rectum depressed posteriorly, the cervix is amputated at the level of the internal os / lower uterine segment using a scalpel.
• The incision is deliberately angulated (wedge-shaped / bevelled) rather than a straight horizontal cut. The anterior cut is made slightly higher than the posterior - this creates a "wedge" shape that makes it easier to cover the raw cervical stump with vaginal mucosa anteriorly.
• The amputated cervix (specimen) is sent for histology.
• The anterior lip of the remaining cervical stump is held with a single-toothed Vulsellum.

Step 3 - Covering the Amputated Cervix

Method A - Sturmdorf Suture (most common)

1. A suture (chromic catgut or Vicryl) is placed through the anterior vaginal flap near its apex.
2. The needle is then passed through the cervical canal from outside inwards, and brought out again laterally.
3. When tied, this pulls the vaginal mucosa flap over and into the cervical canal, neatly covering the raw stump.
4. The same is done for the posterior vaginal flap.
5. The result is that both flaps cover the raw cervical stump on anterior and posterior surfaces, with the canal visible in the middle.

Method B - Bonney's Method

1. A catgut stitch is fixed at the apex of the posterior vaginal flap.
2. The two ends of the suture are passed through the cervical canal and brought out laterally on either side of the new posterior fornix.
3. The ends are tied in the midline, drawing the posterior vaginal flap over the cervical stump.

Step 4 - Plication of Mackenrodt's (Cardinal) Ligaments - The Fothergill Stitch

1. Vaginal skin at the lateral "Fothergill point" (lateral margin of anterior vaginal incision)
2. Through the Mackenrodt / cardinal ligament on that side
3. Through the cervical tissue from outside inwards (from the lateral surface into the cervical canal)
4. Through the cervical tissue from inside outwards on the other side
5. Through the Mackenrodt / cardinal ligament of the opposite side
6. Through the vaginal skin at the Fothergill lateral point of the opposite side
7. Tied firmly

Step 5 - Anterior Colporrhaphy and Posterior Colpoperineorrhaphy

• The redundant vaginal mucosa on the anterior wall is now trimmed.
• The cut margins of the vagina are approximated with interrupted or continuous absorbable sutures.
• The pubocervical fascia has already been plicated (Step 4), reinforcing the bladder base.

• A posterior vaginal incision is made.
• The rectovaginal fascia is plicated.
• Levatorplasty if needed (judicious - over-tightening causes dyspareunia).
• Perineal body reconstructed.
• Vaginal skin and perineum closed.

• Vaginal vault inspected for haemostasis.
• Vaginal pack (ribbon gauze soaked in antiseptic) inserted for 24-48 hours.
• Catheter left in for 24-48 hours post-operatively.

Summary of Operative Sequence

1. D&C (uterine sound → cervical dilatation → endometrial curettage)
     ↓
2. Circumferential vaginal incision at cervicovaginal junction
   - Bladder pushed up anteriorly
   - Check for enterocele posteriorly (repair if found)
   - Bilateral uterosacral + cardinal ligament clamping, division, ligation
     ↓
3. Cervical amputation at internal os (bevelled/wedge cut)
   - Specimen to histology
     ↓
4. Cover cervical stump (Sturmdorf suture or Bonney's method)
     ↓
5. Fothergill stitch: bilateral cardinal ligaments plicated
   anteriorly over cervical stump → uterus anteverted + elevated
     ↓
6. Anterior colporrhaphy (pubocervical fascia plication, trim vaginal skin)
     ↓
7. Posterior colpoperineorrhaphy + perineorrhaphy
     ↓
8. Vaginal pack + catheter

Complications

Intraoperative

• Haemorrhage - from the paracervical venous plexus or uterine vessels; vaginal packing usually controls it
• Bladder injury - if the vesicovaginal plane is not carefully developed; risk highest anteriorly when mobilising the bladder off the cervix
• Ureteric injury - if the clamp on the cardinal ligament is placed too high; the ureter lies ~1.5 cm lateral to the cervix and may be caught
• Rectal injury - rare, during posterior dissection

Post-operative (early)

• Haemorrhage / vault haematoma
• Urinary retention (requires catheterisation)
• Urinary tract infection
• Wound infection / dehiscence
• Deep vein thrombosis

Post-operative (late)

• Cervical stenosis (at the external os) - leads to haematometra / pyometra. The preliminary dilatation is done specifically to reduce this risk.
• Dyspareunia - from vaginal narrowing, especially if over-zealous colporrhaphy
• Recurrence of prolapse (~4-7% at apex, which is actually lower than vaginal hysterectomy)
• Residual/de novo stress urinary incontinence - unmasked after anterior repair; Kelly plication can be added at the time of operation if needed
• Failure to conceive / infertility - from cervical stenosis blocking sperm passage
• Miscarriage - cervical incompetence due to shortened cervical length
• Preterm labour / dystocia - from reduced cervical length and rigidity of the scarred cervix
• Difficulty taking smears - from cervical stenosis; these patients require endocervical cytology

Comparison with Vaginal Hysterectomy

Post-operative Care

• Vaginal pack removed at 24-48 hours
• Catheter removed at 24-48 hours; trial of void
• Mobilise early; VTE prophylaxis (LMWH + TED stockings)
• Topical oestrogen cream post-operatively aids healing (especially peri/post-menopausal women)
• Avoid intercourse for 6-8 weeks
• Avoid heavy lifting for 3 months
• Cervical surveillance (smears) must continue as per national schedule