Preoperative Robotics Planning Facilitates Complex Construct Design in Robot-Assisted Minimally Invasive Adult Spinal Deformity Surgery-A Preliminary Experience.

ABSTRACT

(1) Background: The correction of adult spinal deformity (ASD) can require long, complex constructs with multiple rods which traverse important biomechanical levels to achieve multi-pelvic fixation. Minimally invasive (MIS) placement of these constructs has historically been difficult. Advanced technologies such as spinal robotics platforms can facilitate the design and placement of these constructs and further enable these surgical approaches in MIS deformity surgery. (2) Methods: A retrospective study was performed on a series of ASD patients undergoing MIS deformity correction with ≥eight fusion levels to the lower thoracic spine with preoperative robotic construct planning and robot-assisted pedicle screw placement. (3) Results: There were 12 patients (10 female, mean age 68.6 years) with a diagnosis of either degenerative scoliosis (8 patients) or sagittal imbalance (4 patients). All underwent preoperative robotic planning to assist in MIS robot-assisted percutaneous or transfascial placement of pedicle and iliac screws with multiple-rod constructs. Mean operative values per patient were 9.9 levels instrumented (range 8-11), 3.9 interbody cages (range 2-6), 3.3 iliac fixation points (range 2-4), 3.3 rods (range 2-4), 18.7 screws (range 13-24), estimated blood loss 254 cc (range 150-350 cc), and operative time 347 min (range 242-442 min). All patients showed improvement in radiographic sagittal, and, if applicable, coronal parameters. Mean length of stay was 5.8 days with no ICU admissions. Ten patients ambulated on POD 1 or 2. Of 224 screws placed minimally invasively, four breaches were identified on intraoperative CT and repositioned (three lateral, one medial) for a robot-assisted screw accuracy of 98.2%. (4) Conclusions: Minimally invasive long-segment fixation for adult spinal deformity surgery has historically been considered laborious and technically intensive. Preoperative robotics planning facilitates the design and placement of even complex multi-rod multi-pelvic fixation for MIS deformity surgery.