Lumbar cortical screw, an alternative to the traditional pedicle screw, has more cranially and laterally oriented trajectory within pedicle after being anchored in the pars interarticularis. Such cortical trajectory can lower the risk of nerve root impingement by traditional pedicle screw and reduce the iatrogenic soft tissue damage that occurs with muscle stripping and lateral retraction for traditional trajectory. In addition, lumbar cortical screw proved equivalent pullout strength compared with the traditional pedicle trajectory despite its shorter and smaller screw design.
However, clinical trial is still in the beginning stage, and further clinical studies are required to clarify the actual outcome of the lumbar cortical screw.