In this study, four screws were accurately placed in the pedicles utilizing the Bolt Navigation System in a patient with grade III lytic spondylolisthesis.
65 years old
Lytic spondylolisthesis L4-5 grade III
Fusion L4-5 with pedicle screw fixation and decompression repositioning L4 to L5 as part of a comparative study between traditional O-arm Stealth Station (Medtronic) and the Bolt Navigation System (BNS).
Levels with fixation:
Pedicle screw fixation
Posterior decompression nerve roots L4, Reduction L4 to L5. Surgical time 75 minutes. Blood loss 200 cc.
The patient was positioned in the prone position, prepped and draped per our standard procedures. Axial images for levels L4 and L5 were acquired with the Bolt Navigation System utilizing the patient’s pre-operative CT scans. A standard C-arm was utilized to obtain a true-lateral image of these levels that were then acquired with the BNS.
An open approach was utilized to expose the levels and decompression performed. The BNS was attached to a Medtronic gearshift probe and utilized to determine the correct trajectory for the screw pilot holes. The trajectory was then checked intraoperatively with an O-arm Stealth Station to compare the accuracy of the Bolt system. The BNS was then used to generate the pilot hole which was then tapped and screws placed. All screw trajectories in L4 and L5 were nicely in the middle of the pedicles and in all cases, the telemetry provided by the Bolt Navigation System matched that provided by the O-arm Stealth Station. Screw positioning was then confirmed with a post-operative CT scan.
(Bolt head-to-head with Legacy System)
All four screws were accurately placed in the pedicles utilizing the Bolt Navigation System in a patient with relatively challenging anatomy. The patient’s leg pain completely resolved and reports minimal back pain.