Interpretation of Cervical X-ray

Faizal

Jayamalar

Indications

• Mental status less than alert or intoxicated

• Reports neck pain

• Midline neck tenderness

• Neurologic signs and symptoms

Criteria for excluding cervical spine fractures on a clinical basis

• No neck pain

• No neck tenderness on palpation

• Full, painless, active range of motion of c-spine

• No history of loss of consciousness

• No mental status change

• No neurologic deficit from neck injury

Basic Interpretation

• Mneumonic AABCDS

• Adequacy

• Alignment

• Bone

• Cartilage

• Disc

• Soft tissue

Adequacy

• An adequate film should include all 7 vertebrae and C7-T1 junction.

• It should also have correct density and show the soft tissue and bony structures well.

Alignment

• Assess four parallel lines. – Anterior vertebral line (anterior margin of vertebral

bodies)– Posterior vertebral line (posterior margin of vertebral

bodies)– Spinolaminar line (posterior margin of spinal canal)– Posterior spinous line (tips of the spinous processes)

Any misalignment should be considered evidence of ligamentous injury or occult fracture, and cervical spine immobilization should be maintained until a

definitive diagnosis is made.

Atlanto-occipital alignment

• The anterior margin of the foramen magnum should line up with the dens. A line projected downward from the dorsum sellae along the clivus to the basion should point to the dens.

• The posterior margin of foramen magnum should line up with the C1 spinolaminar line.

Bony Landmarks• Trace the unbroken outline of each

vertebrae (including Odontoid on C2).

• The anterior height of vertebral body should roughly equal posterior height

Bony landmarks

• Pedicles

• Facets

• Lamina

• Spinous process

Cartilaginous Space

• The Predental space = Distance from dens to C1 body– Adults <3mm– Children <5mm

If the space is increased, a fracture of the Odontoid process or disruption of the

transverse ligament is likely.

Disc spaces

• Should be roughly equal in height at anterior and posterior margins.

• Should be symmetric.

• Disc space height should also be approximately equal at all levels.

• In older patients, degenerative diseases may lead to spurring and loss of disc height.

Soft tissue space• Preverteral soft tissue swelling is important in trauma because it is

usually due to hematoma formation secondary to occult fractures. Unfortunately, it is extremely variable and nonspecific.

• Maximum allowable thickness of preverteral spaces is as follows:– Nasopharyngeal space (C1) - 10 mm (adult)– Retropharyngeal space (C2-C4) - 5-7 mm– Retrotracheal space (C5-C7) - 14 mm (children), 22 mm (adults).

• If the space between the lower anterior border of C3 and the pharyngeal air shadow is > 7 mm, one should suspect retropharyngeal swelling (e.g. hemorrhage) indirect sign of a C2 fracture.

• Space between lower cervical vertebrae and trachea should be < 1 vertebral body.

AP view

• Alignment on the A-P view should be evaluated using the edges of the vertebral bodies and articular pillars.

• The height of the cervical vertebral bodies should be approximately equal on the AP view

• The height of each joint space should be roughly equal at all levels.

• Spinous process should be in midline and in good alignment. If one of the spinous process is displaced to one side, a facet dislocation should be suspected

The Odontoid View

• First, assess if the film is Adequate.An adequate film should include the entire odontoid and the lateral borders of C1-C2.

• Alignment.– Occipital condyles

should line up with the lateral masses and superior articular facet of C1.

• The distance from the dens to the lateral masses of C1 should be equal bilaterally– Asymmetry = fracture

of C1/ C2 or rotational abnormality.

• The tips of lateral mass of C1 should line up with the lateral margins of the superior articular facet of C2. – If not, a fracture of C1

should be suspected.

• Bony Margins.– Odontoid should

have uninterrupted cortical margins blending with the body of C2.

Atlanto-axial Dislocation

• Hyperextension injury

• Children>adults

• Head slips forward on C1

• Usually fatal

Neural Arch Fracture of C1

• Most common fracture of C1

• Hyperextension injury

• Not associated with neurologic deficit

• Confused with congenital anomaly

Jefferson Fracture of C1

• Burst fracture

• Caused by compressive force

• Bilateral breaks in anterior and posterior arches

• Open mouth view shows bilateral offset of C1 on C2

• Not associated with neurologic deficit

Hangman’s Fracture of C2

Spondylosis

• disc space narrowing and osteophyte formation