Orthopaedics
Spine and Pelvic Fractures
Spine and pelvic fractures for MBBS and NEET-PG: Denis columns, cord injury, spinal and neurogenic shock, open book pelvis and haemorrhage control, mapped to NMC codes OR2.7 to OR2.9.
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Spine and Pelvic Fractures
Spine and pelvic fractures for MBBS and NEET-PG: Denis columns, cord injury, spinal and neurogenic shock, open book pelvis and haemorrhage control, mapped to NMC codes OR2.7 to OR2.9.
This chapter covers injuries to the axial skeleton and the pelvic ring. It sets out the stability concepts of the spine, the recognition of cord injury and its shock states, and the classification and emergency management of pelvic fractures, where haemorrhage and associated visceral injury dominate the early risk.
High-yield: Spine and Pelvic Fractures
- The spine is stable when at least two of the three Denis columns, anterior, middle and posterior, remain intact.
- A burst fracture involves the middle column and can retropulse bone into the canal, so it carries a real risk of neurological injury.
- Any patient with a suspected spinal injury must be log rolled and immobilised until an unstable injury is excluded.
- Spinal shock is a transient loss of all cord function below the level of injury, and its resolution is marked by the return of the bulbocavernosus reflex.
- Neurogenic shock is hypotension with bradycardia from loss of sympathetic tone in a high cord injury, and it is distinct from spinal shock.
- A pelvic fracture from high energy trauma can cause life-threatening retroperitoneal haemorrhage.
- An anteroposterior compression injury produces the open book pelvis, which is treated early with a pelvic binder to close the ring.
- The Young and Burgess classification groups pelvic ring injuries by the direction of force: anteroposterior, lateral and vertical shear.
- Pelvic fractures may be complicated by bladder and urethral injury, so blood at the urethral meatus warns against passing a catheter.
- A stable minor pelvic fracture, such as an isolated pubic ramus fracture in the elderly, is usually managed conservatively.
- Sacral fractures may injure the sacral nerve roots and cause bladder, bowel and sexual dysfunction.
- A cervical spine injury above C4 threatens the phrenic nerve and diaphragmatic breathing.
- Odontoid peg fractures are an important cause of instability at the craniovertebral junction.
- Vertical shear pelvic injuries are the most unstable and carry the highest risk of major haemorrhage.
Spine and pelvis essentials
- **Denis three columns:** Instability when two or more of the anterior, middle and posterior columns are disrupted.
- **Spinal vs neurogenic shock:** Spinal shock is transient loss of cord function; neurogenic shock is hypotension with bradycardia from lost sympathetic tone.
- **Open book pelvis:** Anteroposterior compression injury; apply a binder early to control retroperitoneal bleeding.
- **Associated injury:** Bladder and urethral injury; blood at the meatus contraindicates catheterisation until assessed.
NMC competencies in this chapter
- **OR2.7:** Fractures and dislocations of the spine and their stability
- **OR2.8:** Spinal cord injury: assessment and early management
- **OR2.9:** Fractures of the pelvis and their complications
Frequently Asked Questions
When is a spinal fracture unstable?
Using the Denis model, the spine is unstable when two or more of its three columns, anterior, middle and posterior, are disrupted, which raises the risk of progressive neurological injury.
How do spinal shock and neurogenic shock differ?
Spinal shock is a temporary loss of all cord reflexes below the injury. Neurogenic shock is a circulatory state with low blood pressure and a slow heart rate caused by loss of sympathetic tone in high cord injuries.
Why is a pelvic binder applied early?
An open book pelvic injury opens up the ring and can bleed heavily into the retroperitoneum. A binder closes the ring, reduces the volume and helps tamponade the bleeding.
Why avoid catheterisation with blood at the urethral meatus?
Blood at the meatus suggests a urethral injury from the pelvic fracture, and passing a catheter blindly can worsen it, so imaging or specialist input is needed first.
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