Spine Surgery
What this domain tests
Degenerative disease and its surgical indications, deformity measurement, trauma classification, spinal infection, and tumor staging.
Core rules
- Thoracolumbar trauma: the TLICS score sums morphology (compression 1, burst 2, translation/rotation 3, distraction 4), posterior ligamentous complex integrity (0, 2, or 3), and neurology (intact 0, nerve root 2, complete cord 2, incomplete cord 3, cauda equina 3). Five or more points favor surgery, three or less nonoperative care.
- Adolescent idiopathic scoliosis: measure the Cobb angle on standing films, assess remaining growth with Risser and Sanders staging. Bracing is considered for curves of 25-40° in a growing child; surgery is generally offered above 45-50°.
- Pyogenic spondylodiscitis: obtain blood cultures and image-guided biopsy before antibiotics in the stable patient. Tuberculous spondylitis is more insidious, spares the disc early, produces cold abscesses and skip lesions, and needs prolonged multidrug therapy.
- Metastatic disease: use Tokuhashi or similar scores for prognosis and decide between decompression plus stabilization and radiosurgery alone.
Worked example
A T12 burst fracture with retropulsion, intact posterior ligamentous complex, and an incomplete cord injury. TLICS = burst 2 + PLC 0 + incomplete cord 3 = 5, which crosses the operative threshold. Posterior short-segment pedicle screw fixation with decompression addresses instability and neural compression; bracing alone would be inadequate given the neurologic deficit.
Traps that cost marks
- Ordering only CT in a patient with a neurologic deficit; MRI is needed for cord, disc, and epidural assessment.
- Confusing TLICS with the AO Spine classification.
- Missing that knee-level or abdominal pain in spondylodiscitis can be the presenting complaint.