Comprehensive Study Notes on Pelvic Fracture Classification and Management

Young-Burgess Classification and Pelvic Injury Mechanisms

• Pelvic fractures are categorized using the Young-Burgess classification system (sometimes referred to as Virgil’s and Young), which focuses on the mechanism of injury and increases in severity based on the force applied.
• The classification assists clinicians, particularly in Emergency Departments, in understanding the potential associated injuries and stability of the fracture.
• There are three primary mechanisms within this system:

Lateral Compression (LC) Fractures

• Graded as LC $1$, LC $2$, and LC $3$.
• Mechanism: Lateral impact, such as a "T-bone" collision in a motor vehicle accident.
• Impact Characteristics: Force is conveyed from a lateral position. A significant impact on one side of the pelvis will almost always result in a corresponding fracture or injury on the contralateral side (both sides are affected).

Anterior-Posterior Compression (APC) Fractures

• Graded as APC $1$, APC $2$, and APC $3$.
• Mechanism: Impacts occurring from the front or back, such as a head-on motor vehicle collision or a crush-type injury where force is applied anteriorly and posteriorly.
• Other Causes: Falling and landing directly on the buttocks can result in these compression forces.

Vertical Shear (VS) Fractures

• This fracture type is categorized independently from the compression grades.
• Mechanism: High-energy vertical force. Examples include falling from a significant height and landing on a single foot, or a driver slamming on the brakes in a vehicle before a sudden high-impact collision, sending force up through the lower limb into the pelvis.

Clinical Pathophysiology and Bleeding Risk

Life-Threatening Hemorrhage

• The internal anatomy of the pelvis allows for massive, hidden blood loss.
• The retroperitoneal space has the capacity to hold between $4\,L$ and $5\,L$ of blood.
• Hemorrhage can also fill the pelvic space itself and track downwards into the thighs, or in males, into the scrotum.
• Severe pelvic fractures carry a high risk of exsanguination.

Open vs. Open Book Fractures

• Open Pelvic Fracture: Defined as a fracture where the bone is exposed through the skin. This carries extremely high morbidity and mortality rates. Patients are often in traumatic arrest.
• Open Book Pelvic Fracture: A radiographic and clinical description of an unstable fracture where the symphysis pubis is separated (opened like a book). This occurs as the supporting ligaments rupture, leading to posterior fractures where the pelvis connects to the sacrum.
• Clinical signs of an open book fracture include leg rotation (one leg splayed outward) or leg shortening.

Clot Preservation

• Movement of the patient must be strictly minimized to prevent the disruption of formed clots (clot disruption). Such disruption can lead to renewed, uncontrollable bleeding.

Procedural Management: Pelvic Binder Application

Anatomical Landmarks and Placement

• The primary landmark for correct placement is the greater trochanter of the femur.
• The midline of the pelvic binder must align with the greater trochanter to be at the level of the pubic symphysis. This ensures the mechanical force reduces the pelvic space and creates a tamponade effect.
• Identifying the Greater Trochanter:
  • It can be felt as a bony prominence on the side of the upper thigh.
  • An alternative landmark (used in New South Wales guidelines) is the level of the patient’s wrists when their arms are positioned straight by their side.
  • If the patient is large and the trochanter cannot be palpated, clinicians should align the binder with the pubic symphysis.
• Common Errors: A $2020$ study from the Royal Brisbane and Women's Hospital (RBWH) found that approximately $50\%$ of pelvic binders applied by paramedics were placed too high (at the level of the iliac crests). If a binder is too high, it may exacerbate the injury by opening the fracture further rather than closing it.

Application Techniques

• Queensland Ambulance Service (QAS) Guideline: Recommends using a small, controlled roll to position the binder under the patient.
• New South Wales Guideline: Suggests sliding the binder under the patient's torso or knees and then moving it into place to avoid any rolling.
• Scope of Action: If a binder is placed incorrectly, it should be repositioned (undone and moved) because an incorrectly placed binder provides no benefit and may cause harm.

Evaluation of Pelvic Immobilization Devices

Comparative Efficacy

• A $2025$ study published in the British Medical Journal (Military) compared various pelvic binding devices over a period of $2\,hours$ to measure mechanical tension stability.
• Prometheus: Found to be the least effective device, with tension dropping off significantly over time due to the Velcro-heavy design.
• Sam Pelvic Splint and TPOD: These were among the best performing devices, maintaining consistent tension.
• Makeshift Devices:
  • A "Sam splint" modified with two holes and a CAT tourniquet was found to be comparable in effectiveness to the TPOD and specialized Sam splints.
  • A military technique involving cutting off military pants at the thigh and using a belt as a binder was also tested and performed better than the Prometheus device.

Current Regional Use

• Prometheus is currently used by QAS.
• TPOD is utilized in New South Wales, Western Australia, and the Northern Territory.
• Victoria continues to use the Sam pelvic splint.

Assessment and Recognition

Clinical Signs and Observations

• Visible swelling in the pelvic region, scrotum, or vaginal lacerations.
• Flank bruising (Ecchymosis).
• Leg rotation or shortening.
• Indicators of hypovolemia (e.g., hypotension, tachycardia).

The "Springing" Assessment

• Springing the pelvis refers to an obsolete technique where a clinician applies inward and outward pressure to the pelvic bones to check for pain or mobility.
• This practice is now strictly contraindicated. It provides no clinical value and risks disrupting internal clots and worsening hemorrhage.

Neurovascular Assessment

• Clinicians should perform a full neurovascular assessment, checking the "6 Ps" (Pain, Pallor, Pulselessness, Paresthesia, Paralysis, and Poikilothermia).
• Pedal Pulse: Check for a pulse between the big toe and the second toe. This helps assess peripheral perfusion, though it may be absent in patients with severe shock/systemic shutdown.

Questions & Discussion

How should you handle a patient who is pregnant with a suspected pelvic fracture?

• Treatment principles remain the same, but clinicians must prioritize the mother to prevent exsanguination.
• To prevent aortocaval compression, the patient should be placed with a left lateral tilt (or use a wedge) to take pressure off the inferior vena cava and improve venous return.
• Be aware that pregnancy hormones make ligaments more flexible, which may increase the likelihood of an open book fracture mechanism.

What if a patient has both a Neck of Femur (NOF) fracture and a pelvic fracture?

• While a NOF fracture is a technical contraindication for a pelvic binder, in high-mechanism trauma where exsanguination is a risk, the pelvic fracture management takes priority. If the clinical picture suggests a pelvic fracture until proven otherwise, apply the binder and consult with a Critical Care Paramedic (CCP).

Should the patient's clothing be removed before applying the binder?

• According to QAS procedural skills, all clothing (including underwear) should be cut and removed. This allows for accurate landmark identification, prevents the clothing from interfering with the binder’s tension, and provides clear access for hospital staff.
• Clinicians must also provide warming blankets to prevent the "lethal triad" of trauma: hypothermia, coagulopathy, and acidosis.

How do QAS guidelines differ for pediatric or small patients using the Prometheus binder?

• QAS indicates that the binder should be cut to size rather than folded to ensure it fits the smaller anatomy correctly while maintaining proper tension.