Fig. 1From: Navigated 2-level posterior lumbar fusion: a 5-cm-incision procedure a The pedicles of L4, L5, and S1 are located with fluoroscopy. b Three transversal lines (arrows) are drawn on the skin to mark the location of the pedicles of L4, L5, and S1. c A 5-cm longitudinal median incision is made. d The navigated instruments are used in the procedure. e A patient tracker is fixed to the spinal process after exposureBack to article page