Transpedicular screw placement: image-guided versus lateral-view fluoroscopy: in vitro simulation

Area of Science:

• Spine surgery
• Surgical navigation
• Orthopedic technology

Background:

• Pedicle screw placement accuracy is crucial for spinal stability and neurological safety.
• Traditional methods rely on identifying anatomical landmarks and intraoperative fluoroscopy for guidance.
• Frameless stereotaxy offers potential for enhanced precision and safety in pedicle screw insertion.

Purpose of the Study:

• To compare the accuracy and efficiency of a novel computer-guided navigation system versus standard image intensifier monitoring for pedicle screw placement.
• To evaluate operative time and screw placement accuracy between the two monitoring methods.

Main Methods:

• An in vitro study simulating pedicle screw placement in eight human cadaveric vertebral sections.
• Four spine surgeons performed transpedicular screw insertions using either image intensifier or image-guided navigation.
• A total of 80 pedicle screws were placed and analyzed for accuracy and time.

Main Results:

• The image-guided technique resulted in fewer cortical disruptions (1 vs. 2) and a smaller average distance to the anterior wall (5 mm vs. 10.7 mm).
• Average screw insertion time was significantly longer with the image-guided system (13.5 minutes) compared to the image intensifier (4 minutes).

Conclusions:

• Computer-aided pedicle screw insertion in the thoracic spine is more accurate than lateral-view fluoroscopy.
• Increased operative time is a current disadvantage of the image-guided navigation system.
• Further advancements in image-guided techniques are expected to decrease overall surgical time.