OR2.7-8 | Axial Skeleton Injuries — Practice Quiz

Correct. A circumferential pelvic binder reduces pelvic volume, compresses bleeding venous plexuses, and is the first-line haemorrhage control measure for open-book pelvic fractures in the haemodynamically unstable patient.

An open-book pelvic fracture causes massive haemorrhage by expanding pelvic volume; emergent circumferential compression with a pelvic binder or sheet reduces this volume and tamponades venous/bony haemorrhage before definitive fixation.

A pelvic binder is the first-line life-saving measure — it reduces pelvic volume and tamponades haemorrhage immediately. Operative fixation and CT angiography are deferred until the patient is stabilised.

Correct. Vertical shear injuries cause superior hemipelvis displacement that directly stretches or avulses the lumbosacral plexus (L4–S1), producing lower limb neurological deficit.

Vertical shear pelvic fractures disrupt both the anterior and posterior pelvic ring, including the posterior sacroiliac complex. The lumbosacral plexus — especially L4, L5, and S1 roots — and the superior gluteal artery are most at risk due to the severe displacement.

The lumbosacral plexus is the structure most at risk in vertical shear pelvic fractures due to the dramatic posterior ring disruption and superior displacement of the hemipelvis.

Correct. Maintaining strict spinal precautions and obtaining urgent CT (or MRI) is the priority to characterise the injury, plan decompression/stabilisation, and prevent secondary cord injury from further movement.

In a haemodynamically stable patient with a suspected unstable spine injury and neurological deficit, maintaining spinal precautions (cervical collar, log-roll, hard surface transfer) during assessment and obtaining urgent MRI/CT prevents secondary cord injury from additional displacement.

Spinal precautions must be maintained until bony instability is excluded. Imaging is needed to plan definitive management. Moving the patient without precautions risks converting an incomplete injury to a complete one.

Correct. Until bony stability is restored (traction, halo vest, or surgical fixation), the spine must be kept immobilised. Log-rolling in a coordinated team — maintaining cervical alignment — is the only safe positional change method.

In unstable cervical spine injuries with complete neurological deficit, mobilisation is only safe after bony stability has been restored (either by halo vest/cervical orthosis after closed reduction, or surgical fixation). Log-rolling with maintained cervical alignment is mandatory for all positional changes until stability is confirmed.

Bony instability persists even in complete cord injury; further displacement can injure surviving roots at the injury level or adjacent levels. Rigid immobilisation and coordinated log-rolling are mandatory.

Correct. With FAST negative and persistent haemodynamic instability, pelvic arterial bleeding is the most likely source. After external stabilisation (binder), angiography with embolisation is the definitive haemostatic intervention.

In haemodynamically unstable pelvic fractures with a negative FAST (no intra-abdominal source), the haemorrhage is retroperitoneal/pelvic. Interventional radiology (angiography and embolisation) is the most effective intervention once external stabilisation has been applied and intra-abdominal injury excluded.

When FAST excludes abdominal injury and the patient remains haemodynamically unstable with a pelvic fracture, arterial pelvic bleeding is the culprit. Angioembolisation is the definitive intervention after binder application.

Correct. Conus medullaris syndrome presents with saddle anaesthesia, early bladder and bowel dysfunction (often urinary retention with overflow), and preserved or minimally affected lower limb motor function — unlike the complete flaccid paralysis of a cauda equina injury.

The conus medullaris ends at approximately L1–L2. Injury at T12–L1 classically produces a mixed upper and lower motor neuron picture: bladder/bowel dysfunction, saddle anaesthesia, preserved but altered lower limb reflexes. Perianal numbness and bladder dysfunction (saddle anaesthesia + bladder retention) are hallmark conus signs.

Conus medullaris injury characteristically produces saddle anaesthesia and sphincter dysfunction in a patient who retains some lower limb motor function. This distinguishes it from complete cord injury and from cauda equina syndrome.

Correct. In patients with known unstable pelvic fractures, a scoop stretcher (or similar device) that lifts the patient without inducing a rolling motion is preferred to avoid displacing the fracture and worsening haemorrhage.

Log-rolling an unstable pelvic fracture patient risks displacing the fracture and worsening haemorrhage. The log-roll must be performed with at minimum four team members: one designated to the head/cervical spine, two controlling the trunk and pelvis, and one to examine. The pelvis must be kept in neutral rotation throughout.

Log-rolling an unstable pelvic fracture risks displacing the fracture. A scoop stretcher that lifts without rolling preserves pelvic alignment and prevents additional haemorrhage.

Correct. A stable compression fracture (anterior wedging only, no posterior cortex disruption, no neurological deficit) is managed conservatively with analgesia, a TLSO brace, and supervised early mobilisation to prevent deconditioning.

Stable osteoporotic compression fractures without neurological deficit (no posterior cortex disruption, no kyphosis >30 degrees) are initially managed conservatively: analgesia, thoracolumbar orthosis (TLSO), and early mobilisation with physiotherapy. Surgical intervention is reserved for progressive deformity or neurological compromise.

Stable compression fractures without neurological deficit and without posterior disruption are treated conservatively with analgesia, brace, and early mobilisation; surgery is not indicated initially.