Computer-assisted Patient-specific Prototype Template for Thoracolumbar Cortical Bone Trajectory Screw Placement: A...

Area of Science:

• Spinal surgery
• Orthopedic biomechanics
• Medical device development

Background:

• The cortical bone trajectory (CBT) screw technique offers improved screw fixation and less invasive exposure in spinal surgery.
• Accurate screw placement is paramount for the success of the CBT technique.
• Patient-specific drill templates present a potential solution for enhancing accuracy and safety.

Purpose of the Study:

• To evaluate the accuracy and safety of patient-specific, computed tomography (CT)-based, rapid prototype drill guide templates for the CBT technique in the thoracolumbar spine.

Main Methods:

• CT scans of 7 cadaveric thoracolumbar spines were used to create 3D models.
• Customized drill templates with guides for the CBT technique were designed using computer software and fabricated via rapid prototyping.
• 80 templates (T11-L5) were used to guide screw placement without fluoroscopic control, followed by postoperative CT assessment.

Main Results:

• A total of 80 CBT screws were inserted across 7 cadaveric spines (T11-L5).
• Postoperative CT scans revealed no screw misplacement or bony perforation.
• The patient-specific drill template system demonstrated high accuracy and safety in guiding screw placement.

Conclusions:

• Patient-specific rapid prototype drill templates are effective and safe for accurate screw placement using the CBT technique in the thoracolumbar spine.
• This customized approach adapts to individual spinal anatomy, offering a promising method for precise surgical guidance.
• The study highlights the potential of drill templates to optimize CBT screw insertion, improving surgical predictability and patient safety.