Operative Planning

• Review imaging (plain radiographs, magnetic resonance imaging, myelogram/computed tomography myelogram)

Routine Equipment

• Basic lumbar laminectomy and fusion instruments

Special Equipment

• Thoracolumbar pedicle screw implants
  
• Iliac fixation system
  
• Neurophysiological monitoring for somatosensory evoked potentials, motor evoked potentials, and pedicle screw testing with triggered electromyography (EMG)

Operating Room Set-up

• Open-frame spinal table with traction set-up (optional)
  
• Headlight
  
• Two Bovie cauteries for simultaneous bilateral exposure
  
• Cell saver
  
• Smoke evacuator

Anesthetic Issues

• Sufficient intravenous access for blood transfusion
  
• Arterial line for blood pressure monitoring
  
• Wake-up test may be required during procedure
  
• For complex procedures, consider epsilon aminocaproic acid to reduce blood loss

Positioning

• Gardner-Wells tongs placed in standard position (1 cm above pinnae, inline with external auditory meatus)
  
• 15 lb of inline traction
  
• If using head holder instead of traction, ensure no ocular pressure
  
• Three pads on each side: 3 to 4 cm distal to axillae, proximal and distal to anterior superior iliac spine
  
• Hips extended to maximize lumbar lordosis
  
• Shoulders abducted and elbows flexed 90 degrees
  
• All pressure points well padded

Sterile Scrub and Prep

• As in posterior thoracic approach

Incision

• Linear incision extending from tip of spinous process one level proximal to upper instrumented vertebra (UIV) to spinous process of lower instrumented vertebra (LIV)

Exposure

• Bilateral subperiosteal exposure to tips of transverse processes of all levels to be included in construct
  
• Maintain integrity of supra- and interspinous ligament proximal to UIV and distal to LIV
  
• Avoid disruption of facet capsules of levels excluded from construct
  
• Thoroughly clean all soft tissue from dorsal bony surfaces of spine

Decompression

• Perform decompression (laminotomy, laminectomy, foraminotomy) at appropriate levels

Pedicle Screw Fixation

• Place bilateral pedicle screws at each segment
  
• Begin distally and work proximally
  
• Ensure appropriate screw length based on preoperative measurements and intraoperative confirmation
  
• Optimal SI screws are bi- or tri-cortical (exit ventrally at sacral promontory)
  
• Obtain anteroposterior (AP) and lateral radiographs to confirm proper screw placement
  
• Test triggered EMG threshold for each screw distal to T6