Review Question - QID 3788

The patient has an underlying anklyosing spinal disorder, most likely ankylosing spondylitis (AS) in light of his genetic testing. Spinal fractures in these populations behave as long bone injuries and require fusion with long segment pedicle screw fixation.

Ankylosing spondylitis is an autoimmune disease primarily affecting the axial spine and associated with the HLA-B27 phenotype in about 90% of cases. Non-orthopaedic manifestations can include uveitis, pulmonary fibrosis, and amyloidosis. Imaging typically shows a classic bamboo spine and marginal syndesmophytes with squaring of the vertebral bodies. Given the autofusion of the spine, injuries in this population behave differently and are typically extension-type three-column injuries with significant epidural bleeding. Surgical stabilization with long constructs is the treatment of choice, and nonoperative management is reserved for patients with severe medical comorbidities.

Einsiedel et al. reviewed 37 cases of cervical spine fractures from two institutions in patients with AS. They found significant early fixation failures in patients treated with either anterior or posterior fixation only. Therefore, they recommend both anterior and posterior fixation in the cervical spine and high index of suspicion for spinal injury in this population.

El Tecle et al. reviewed the management of spine injuries in AS. The subaxial spine, cervicothoracic junction, and thoracolumbar junction are the most common areas of injury. Given poor outcomes with nonoperative management and increased difficulty of delayed surgical management patients initially treated non-operatively, they recommend surgical fixation in patients who are healthy enough for surgery. Patients with AS are at much higher risk of perioperative complications.

Figures A and B are coronal and sagittal CT scan images showing an extension type injury in an AS patient through the L1-L2 disc space and superior endplate of L2 extending into the posterior column.

Incorrect Answers:
Answers 1-3: Nonoperative management is reserved for patients who are not healthy enough for surgery. Appropriate bracing depending on location of fracture and early mobilization would be the mainstay of nonoperative management.
Answer 4: Given the altered biomechanics of the spine in AS, injuries behave similar to long bone fractures and require long segment fixation for fusion.