The feasibility and accuracy of double-channel pedicle screws fixation / 中华骨科杂志

ABSTRACT

Objective:To investigate the feasibility and accuracy of inserting two pedicle screws through different trajectories in the same pedicle.Methods:3D image data of 100 adults lumbar spine in the database of radiology department from March 2019 to October 2019 were randomly selected. The cancellous bone width and height of pedicles were measured by using Mimics software. The diameters of pedicle screws and revision screws were chosen according to the width of pedicles. A revision screw was implanted into the same vertebral pedicle after inserting a traditional pedicle screw. The successful rates were analyzed. The head inclination angles and outer inclination angles were measured.Results:1) Pedicle morphology the height of L 1-L 5 pedicle cancellous bone were 10.94±2.22 mm, 9.76±1.82 mm, 9.47±1.77 mm, 8.71±1.52 mm, and 8.66±1.62 mm respectively, showing a trend of gradually decreasing. The width of L 1-L 5 pedicle cancellous bone were 5.01±1.61 mm, 5.48±1.69 mm, 6.95±1.79 mm, 8.58±1.85 mm, and 11.72±2.25 mm respectively, showing a trend of gradually increasing. 2) The successful rates of dual pedicle screws fixation 57.2% dual pedicle screws fixation were successfully planned in 500 pedicles of 100 people. The successful rates of L 1-L 5 were 100%, 93.2%, 79.8%, 27.6%, and 11.0% respectively, showing a trend of gradually increasing. As the width of pedicles increased, the successful rates gradually decreased. (3) The angle of revision screws the head inclination angles of L 1-L 4 revision screws were 9.73°±3.96°, 9.57°±4.58°, 9.13°±4.11°, and 6.10°±3.00° respectively, showing a decreasing trend; the outer inclination angles were 9.57°±3.85°, 8.76°±4.83°, 6.61°±4.93°, and 5.03°±5.80° respectively, showing a decreasing trend. The head inclination angle of L 5 revision screw was 28.42°±6.06° and the outer inclination angle was 150.58°±2.08°. Conclusion:CBW is related to the successful rate of dual trajectory pedicle screws fixation. Measurement of CBW is of great significance for the feasibility and accuracy of double-channel pedicle screws fixation before operation. The digital simulation of pedicle screw fixation provides reference for the clinical application of double-channel pedicle screws fixation.