of C2/3 treated with lag screw fixation
A 24 year old female presents as a secondary
transfer to the regional trauma centre. That night she has been
walking by the side of the road with her boyfriend when a car lost
control and veered into them. The boyfriend was killed at the scene.
She had a head injury with Glasgow
Coma Scale of 5 on arrival. A lateral cervical spine X-ray showed
fracture-dislocation at C2/3. At the receiving hospital she was
intubated and ventilated prior to transfer.
At the regional trauma centre she had a
full trauma response performed. No additional injuries were found.
The initial lateral radiograph
of her cervical spine is shown below.
She was placed in carbon fibre halo stabilisation.
Computed tomography (CT) confirmed these findings, and she was taken
directly for Magnetic Resonance Imaging (MRI) of her cervical spine.
The T2 weighted image, shown below, identified a posterior disc
herniation with impingement onto the cervical spinal cord. There
was some contusion in the substance of the cord.
CT of her brain showed a left parietal contusion,
with effacement of the ventricles a some midline shift. She had
soft tissue swelling of the right side, indicating a contre-coup
She was taken to the operating room for insertion
of intracranial pressure monitor, and decompression / stabilisation
of the C2/3 level. This was performed through an anterior approach
through the right side. At operation the C2/3 level was identified.
A large anterior fragment was separate from the rest of the body
of C2, and the C2/3 disc was herniated posteriorly. This was excised,
and the fracture stabilised anteriorly with two lag screws across
the C2/C3 space, including the anterior fragment. Post-operative
lateral radiograph is shown below :
She subsequently spent 3 weeks in the neurosurgical
intensive care unit, before being transferred to the regional spinal
injuries unit for rehabilitation. She has regained good motor power
in her left arm and leg, though she has a spastic right hemiparesis
following the intracranial injury. She has a good range of pain
free neck movements.
As far as we are aware, this is the first time
lag screws have been used in this manner. Lag screw fixation is
common for fractures of the odontoid, and also for fusion at the
atlantooccipital and lumbosacral junction, where they are placed
across the facet joints (Magerl type fusion).
The cervical cord required an anterior approach
to decompression to adequately manage the disc herniation. An anterior
fusion is usually completed with bone graft and plate fixation.
However in this patient the large anterior fragment of C2 prevented
use of this technique.
Also of interest is the value of the MRI
scan in this patient. Without this, the full extent of soft tissue
disruption is not appreciated, and canal compromise from the disc
protusion can be clearly seen. There was no bony impingement on
the cord visible on either plain radiography or CT scan.