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Case 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 type injury.
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. Discussion 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.
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