ABSTRACT
Lumbar pedicle screw fixation is a common procedure performed in spinal surgery. In traditional open approaches, extensive midline exposure extends above and below the instrumented levels allowing lateral retraction of the soft tissues to visualize the pedicle screw entry points at the intersection of the transverse process and facet complexes. Percutaneous lumbar pedicle screws may be used to treat degenerative disc disease, spondylolisthesis, and spinal trauma. In the upper lumbar spine, the pedicles are oval, with a greater height than transverse diameter, making the transverse diameter the limiting feature in determining the appropriate pedicle screw diameter. The starting point for open pedicle screws in the lumbar spine is close to the junction of the transverse process and the facet complex. The popularity of minimally invasive spinal arthrodesis procedures is growing, and percutaneous pedicle screws are often used to minimize soft-tissue trauma.
