A study published in Spine Deformity — the journal of the Scoliosis Research Society — examines the effectiveness of preoperative three dimensional CT scans in adolescent scoliosis patients.
The authors examined 62 patients with an average age of 15.1 years old. The average deformity was 76 degrees with a range of 52 degrees to 80 degrees. Average follow up was 35 months and 710 pedicle screws were placed.
Here are five findings from the article:
1. A breakdown of the average perioperative task times in the navigation group include:
• Average tracker placement time: 55 seconds
• Registration time: 94.5 seconds per vertebra
• Screw tract formation: 131.1 seconds on the concave side
• Screw tract formation: 129.5 seconds for the convex side
2. The average total procedure time was 3.5 hours, with a range of two to seven hours. The freehand group had 470 pedicle screw placements with an average placement time of 135.2 seconds per screw.
3. The average overall registration accuracy was 0.7 mm in the navigation group. However, it's important to note subtle differences in the patient's position on the CT couch and operating table can lead to navigation errors, according to the study.
4. Pedicle integrity was breached in 1.6 percent trajectories in the navigation group; in the freehand group, pedicle integrity was breached in 5.1 percent of trajectories. Screw placement accuracy with 3D navigation guidance has reached 96.7 percent, according to the study's discussion, and in a previous study surgeons reported proper tract preparation in 98.4 percent of cases.
5. There were no neurological or other complications reported. There weren't any instrument destabilizations in the spine during the short or long-term follow up. "Intraoperative optic fluoroscopic navigation based on anatomic landmark registration to preoperative 3D-CT spine images enables precise pedicle screw placement with only minor increase in pedicle preparation time in patients with adolescent idiopathic scoliosis," the study authors concluded.