Emergency Medicine · Trauma
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Has a bimodal distribution: young adults from high-energy blunt trauma and the elderly from low-energy falls.
Immediate treatment for hemorrhagic shock is a pelvic binder centered over the greater trochanters.
AP pelvic radiograph is the initial trauma screen; CT pelvis is the gold standard for definitive classification.
Massive retroperitoneal hemorrhage is mostly venous from the presacral plexus, with arterial bleeds causing rapid exsanguination.
Blood at the urethral meatus or a high-riding prostate signals urethral injury requiring a retrograde urethrogram before a Foley.
Refractory shock despite binding requires preperitoneal packing or angiographic embolization.
Avoid repeated pelvic rocking during exam to prevent dislodging early clots.
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A 34-year-old man is brought in after a motorcycle collision. His blood pressure is 82/50 mm Hg and heart rate is 130/min. There is perineal ecchymosis and blood at the urethral meatus. AP pelvic radiograph shows an open-book pelvic ring disruption with widening of the pubic symphysis.
Which of the following is the most appropriate immediate intervention?
Application of a pelvic binder over the greater trochanters.
An unstable open-book pelvic fracture with hemodynamic instability is managed first by a pelvic binder centered on the greater trochanters to reduce pelvic volume and tamponade venous bleeding. Blood at the urethral meatus mandates a retrograde urethrogram before any Foley catheter placement.
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Etiology / Epidemiology
Bimodal distribution affecting young adults via high-energy blunt trauma and the elderly via low-energy falls.
Clinical Manifestations
Presents with severe pelvic/groin pain, inability to bear weight, perineal ecchymosis, and potentially lethal hemodynamic instability.
Diagnosis
AP pelvic radiograph is the initial trauma screen, while CT pelvis is the gold standard for definitive classification.
Treatment
Immediate application of a pelvic binder over the greater trochanters for hemorrhagic shock, followed by angiographic embolization or surgical fixation.
Prognosis
High morbidity and mortality driven by massive retroperitoneal hemorrhage and subsequent venous thromboembolism.
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Epidemiology & Etiology
Pelvic fractures exhibit a bimodal demographic, primarily affecting young adults via high-energy blunt trauma like MVCs or crush injuries. In the elderly, they frequently result from low-energy falls superimposed on osteoporosis. Adolescents may present with avulsion fractures at tendinous insertions during explosive athletic movements, which rarely cause hemodynamic compromise.
Pertinent Anatomy
The pelvic ring consists of the sacrum and two innominate bones joined by the pubic symphysis anteriorly and sacroiliac ligaments posteriorly. Because it functions as a rigid ring, isolated single fractures are rare; disruption typically occurs in two or more places. The presacral venous plexus and branches of the internal iliac artery lie directly against the bone, making them highly vulnerable to shearing forces.
Pathophysiology
High-energy impact disrupts the osteoligamentous ring, leading to abnormal pelvic expansion and an increase in true pelvic volume. This expansion eliminates the natural tamponade effect, precipitating massive retroperitoneal hemorrhage. Bleeding is primarily venous from the presacral venous plexus (80%), though arterial sources (20%) can cause rapid exsanguination. Associated shear forces simultaneously risk urethral or bladder rupture and lumbosacral plexus avulsion.
Clinical Manifestations
Patients present with profound pelvic pain, inability to ambulate, and frequent hemodynamic instability. Classic physical signs include Destot sign (superficial hematoma above the inguinal ligament) and extensive perineal or scrotal ecchymosis. A high-riding prostate or blood at the urethral meatus are critical red flags for concurrent genitourinary trauma. Lower extremities may appear shortened and externally rotated, particularly in an open book fracture.
Diagnosis
Initial evaluation must follow the ATLS protocol, utilizing an AP pelvic radiograph as the primary screening tool in the trauma bay. The gold standard for detailed anatomic evaluation and operative planning is a CT pelvis without contrast. If urethral injury is suspected based on meatal blood, a retrograde urethrogram must be performed before inserting a Foley catheter to prevent completing a partial tear.
Treatment
Immediate stabilization of a hypotensive patient requires a pelvic binder or sheet centered strictly over the greater trochanters to reduce pelvic volume and promote venous tamponade. If hemorrhagic shock persists despite binding and fluid resuscitation, emergent preperitoneal pelvic packing or angiographic embolization is indicated. Definitive management for mechanically unstable ring disruptions requires Open Reduction Internal Fixation (ORIF) or external fixation. Avoid excessive movement or repeated pelvic rocking during examination to prevent dislodging early clots.
Prognosis
Mortality rates can exceed 30% in patients presenting with hemorrhagic shock or open pelvic fractures. Long-term survivors frequently suffer from chronic pelvic pain, sexual dysfunction, and persistent neurologic deficits. Due to major venous stasis and endothelial injury, patients are at extreme risk for venous thromboembolism (VTE) and require aggressive prophylaxis once bleeding is controlled.
Differential Diagnosis
1. Acetabular Fracture: Involves the hip joint articulation rather than the pelvic ring, typically presenting with deep hip pain exacerbated by axial loading.
2. Hip Dislocation: Presents with a shortened, internally rotated leg (if posterior) and a structurally intact pelvic ring on imaging.
3. Proximal Femur Fracture: Common in elderly falls, presenting with a shortened, externally rotated leg but normal pelvic ring integrity.