Grade II Spondylolisthesis: Reverse Bohlman Procedure with Transdiscal S1-L5 and S2 Alar Iliac Screws Placed with Robotic Guidance

Abstract

Grade II spondylolisthesis remains a complex surgical pathology for which there is no consensus regarding optimal surgical strategies. Surgical strategies vary regarding extent of reduction, use of instrumentation/interbody support, and anterior versus posterior approaches with or without decompression. Here we provide the first report on the efficacy of robotic spinal surgery systems in support of the treatment of grade II spondylolisthesis. Using 2 illustrative cases, we provide a technical report describing how robotic spinal surgery platform can be used to treatment grade II spondylolisthesis with a novel instrumentation strategy. We describe how the "reverse Bohlman" technique to achieve a large anterior fusion construct spanning the pathological level and buttressed by the adjacent level above, coupled with a novel, high-fidelity posterior fixation scheme with transdiscal S1-L5 and S2 alar iliac (S2AI) screws placed in a minimally invasive fashion with robot guidance allows for the best chance of fusion in situ. The reverse Bohlman technique coupled with transdiscal S1-L5 and S2AI screw fixation accomplishes the surgical goals of creating a solid fusion construct, avoiding neurologic injury with aggressive reduction, and halting the progression of anterolisthesis. The use of robot guidance allows for efficient placement of these difficult screw trajectories in a minimally invasive fashion.