An anatomic, radiographic, and biomechanical assessment of extrapedicular screw fixation in the thoracic spine.

This study performed a thorough review of the pertinent thoracic spine anatomy to determine the appropriate landmarks for extrapedicular screw placement and indentified the anatomic structures at risk; assessed the safety and accuracy of the newly proposed screw insertion technique; determined the stability and strength of this new screw position through biomechanical testing; and analyzed the stability of this extrapedicular screw location with respect to bone mineral density of the vertebra.