Pfannenstiel Approach to the Pubic Symphysis

What it exposes. The Pfannenstiel approach gives direct anterior access to the pubic symphysis, the superior pubic rami and the retropubic space of Retzius through a single transverse suprapubic incision. It is the standard anterior exposure for symphyseal plating in open-book (APC) pelvic ring injuries and forms the superficial part of the modified Stoppa intrapelvic approach to the acetabulum. Why transverse (and not midline). The incision lies two fingerbreadths above the pubic crest and follows Langer's lines, healing with an excellent cosmetic result and a low hernia rate compared with a vertical midline laparotomy. It can be extended laterally along the pelvic brim into the Stoppa approach without a second skin incision, and proximally in the midline if abdominal exploration is needed. Principal indications. - Symphyseal diastasis in APC II and APC III pelvic ring injuries requiring plate stabilisation

• Displaced superior pubic ramus fractures with anterior ring instability
• Combined anterior ring and acetabular fractures (transverse, T-type, anterior column) via the Stoppa extension
• Revision surgery for symptomatic symphyseal nonunion or malunion
• Open-book injuries with urological or bowel entrapment requiring direct access Contraindications are mostly relative: active infection or open wounds in the suprapubic region, dense adhesions from previous lower abdominal surgery, a severe bladder injury requiring urological repair first, or patient instability precluding anterior pelvic surgery. Alternatives. A vertical midline laparotomy when simultaneous abdominal exploration is required; the modified Stoppa (intrapelvic) approach for full anterior column and acetabular access through the same skin incision; the ilioinguinal approach when a lateral window is needed for the iliac wing or posterior column; and percutaneous anterior ring fixation for minimally displaced ramus fractures in stable patterns. Position and landmarks. Supine on a radiolucent table with full fluoroscopic access (inlet, outlet, obturator and iliac oblique views), the C-arm brought in from the opposite side. Insert a urinary catheter and confirm it is draining before skin preparation. Slight hip flexion (10 to 15 degrees) relaxes the iliopsoas and rectus. Palpate and mark the pubic symphysis, pubic crest, superior pubic rami, the pectineal eminence and the ASIS (the lateral limit if ramus exposure is needed). A cell saver and cross-matched blood should be available for high-energy pelvic injuries.

Work down through the abdominal wall in the midline, decompress and protect the bladder, enter the space of Retzius, and then — for ramus work — develop the subperiosteal plane out along the superior pubic ramus where the corona mortis must be found and controlled before any plate is placed.

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Structures at risk, by layer

Corona mortis injury management. If brisk bleeding is encountered from the superior ramus, apply direct pressure with a sponge or finger — do not blindly clamp. Pack the space of Retzius firmly and maintain pressure for 5 to 10 minutes; if bleeding persists, carefully remove the packing, identify the vessel and ligate both proximal and distal ends. For uncontrolled arterial bleeding, leave the packing in place and obtain interventional radiology embolisation. Most injuries are venous, but arterial injury can cause life-threatening retroperitoneal haemorrhage. Post-operative complications

Extensile options. The three rectus-management variants map directly onto how far the exposure is taken: a classic midline linea alba split for an isolated symphysis, a unilateral rectus release for wider ramus exposure, and an extended Pfannenstiel combined with the Stoppa intrapelvic plane for acetabular fractures. - Modified Stoppa (intrapelvic) extension. After entering the space of Retzius, release the rectus insertion and develop the extraperitoneal plane along the pelvic brim, elevating the iliopsoas from the anterior column and quadrilateral surface. This exposes the entire anterior pelvic ring, anterior column and acetabulum without a second skin incision, and avoids the morbidity of the lateral window of the ilioinguinal approach.

• Lateral extension toward the ilioinguinal. Extend the incision laterally along the inguinal ligament toward the ASIS and develop the plane between the external oblique aponeurosis and the inguinal ligament to reach the iliac wing and anterior column from a lateral window.
• Proximal midline extension. If simultaneous laparotomy is needed, extend the incision proximally in the midline through the linea alba toward the umbilicus — rarely needed in isolated pelvic ring trauma.
• Combined posterior approaches. For APC III injuries with posterior ring disruption, combine the Pfannenstiel approach with percutaneous or open posterior fixation (iliosacral screws, sacral bars or posterior tension-band plating) in the same or a staged procedure. Closure. Irrigate the retropubic space copiously and achieve meticulous haemostasis of the deep dorsal vein complex. Reattach the rectus abdominis to the pubic crest or linea alba with heavy absorbable or non-absorbable suture (number 1 or 2 PDS or Prolene) passed through drill holes in the pubis or the ligamentous attachments. Close the anterior rectus sheath with running absorbable suture (number 0 PDS), approximate Scarpa's fascia, and close skin with subcuticular absorbable suture or staples; consider mesh reinforcement in obese patients or poor tissue quality. Confirm reduction and plate position on pelvic inlet, outlet and oblique views, with CT if screw position near the hip joint or reduction quality is in doubt. Rehabilitation. Touch or non-weight bearing on the affected side for 6 to 12 weeks depending on posterior ring stability, with crutches or a walker; gentle hip flexion and abduction as pain allows, avoiding aggressive external rotation for the first 6 weeks to protect the symphyseal repair. Follow-up inlet and outlet radiographs at 6 and 12 weeks, progressing weight bearing as healing permits. Consent (globally applicable). Discuss bladder injury (1 to 3 percent), corona mortis bleeding requiring ligation or embolisation (2 to 5 percent), abdominal wall hernia (2 to 5 percent), chronic symphyseal pain or dyspareunia (10 to 20 percent), infection (2 to 5 percent), and the need for posterior ring stabilisation in APC III injuries.

• Symphyseal plating for APC II/III pelvic ring injuries — the principal operation, open reduction and plate fixation of symphyseal diastasis with a 3.5 mm reconstruction plate resisting the external rotation forces that opened the symphysis.
• Fixation of displaced superior pubic ramus fractures and anterior ring stabilisation in combined pelvic-acetabular injuries.
• Modified Stoppa intrapelvic approach to the acetabulum — anterior column, quadrilateral surface and medial wall — developed through the same skin incision.
• Exposure for transverse and T-type acetabular fracture ORIF when combined with the Stoppa plane.
• Debridement and stabilisation of symphyseal infection or osteomyelitis (rare).

The Pfannenstiel approach is used worldwide for symphyseal plating in APC pelvic ring injuries and as the anterior window for the modified Stoppa approach to acetabular fractures. Principles converge across examination systems. Side-by-side principles (where guidance converges): - AO Foundation — CT mandatory for all pelvic ring and acetabular fractures; corona mortis identification required before superior ramus plating; staged management with external fixation for haemodynamically unstable patients.

• BOA / BOAST — early pelvic binder application, urological assessment for bladder injury, joint orthoplastic care for open pelvic injuries; definitive fixation only once soft tissues and physiology permit.
• OTA / AAOS — anatomic reduction of the symphysis and posterior ring; plate fixation resisting external rotation forces; identification and protection of the corona mortis. Registry and population evidence: - APC II and III injuries comprise approximately 15 to 20 percent of pelvic ring fractures in high-energy trauma registries.
• Symphyseal plating through a Pfannenstiel approach achieves stable anterior ring fixation in greater than 90 percent of cases when combined with appropriate posterior stabilisation.
• Corona mortis injury rates have fallen from a historical 10 to 15 percent to less than 3 percent in modern series with deliberate identification. Global practice variation. In high-resource settings, dedicated pelvic reconstruction plates and routine CT with three-dimensional reconstruction are standard. In resource-limited settings the same biomechanical principles are achieved with contoured reconstruction plates or even one-third tubular plates, and external fixation has a larger role for temporisation.