Accuracy of pedicle screw placement using patient-specific template guide system

Area of Science:

• Neurosurgery
• Orthopedic Surgery
• Medical Device Technology

Background:

• Cervical pedicle screw insertion frequently results in malpositioning, increasing the risk of neurovascular complications.
• Developing accurate methods for screw placement is crucial for patient safety in cervical spine surgery.

Purpose of the Study:

• To evaluate the accuracy and effectiveness of a novel patient-specific screw guide system for cervical pedicle screw (PS) placement.
• To assess the potential of this system in minimizing screw malposition and associated risks.

Main Methods:

• A retrospective clinical evaluation of 17 patients undergoing posterior cervical fusion using the patient-specific guide system.
• Preoperative 3D planning and custom screw guide fabrication for 77 pedicle screws (C3-C7).
• Postoperative CT scans to measure screw deviations from planned trajectories and assess pedicle perforation.

Main Results:

• 98.7% of screws (76/77) were accurately placed within the pedicle without neurovascular injury.
• Mean screw deviations were minimal (axial: 0.43-0.56 mm; sagittal: 0.43-0.63 mm).
• Mean angular deviations were low (sagittal: 2.94°, axial: 2.53°), with slight increases in cranial vertebrae.

Conclusions:

• The patient-specific screw guide system is highly effective for precise cervical pedicle screw insertion.
• This innovative technique offers a reliable solution to enhance surgical accuracy and reduce complication rates in cervical spine procedures.