Minimally invasive pedicle screw fixation

Lumbar fusion is a commonly practiced method of achieving spinal fixation in a variety of pathological entities that affect the spine. Pedicle screws are frequently used to provide immediate stabilization while the arthrodesis occurs. Conventional techniques of lumbar fusion and pedicle screw placement are associated with significant iatrogenic soft tissue injury and potential functional impairment. Minimally invasive lumbar fusion techniques seek to minimize this injury without adversely affecting the efficacy of the procedure. Percutaneous pedicle screws can be used to supplement various conventional and minimally invasive lumbar fusion techniques such as anterior lumbar interbody fusion, transforaminal lumbar interbody fusion, posterior lumbar interbody fusion, and posterolateral fusion. Navigation through the pedicle is the most critical step of percutaneous pedicle screw placement, and consequently the surgeon must be comfortable interpreting radiographic images. Once the pedicle has been cannulated a K-wire is placed, and both tapping and screw placement are performed over the wire. This manuscript describes the technique required for safe minimally invasive pedicle screw placement and reviews both surgical pearls and pitfalls associated with the procedure.