Usefulness and Radiological Evaluation of Accuracy of the Innovative “Smart” Hand Technique for Pedicle Screw Placement: An Anatomical Study

Özet

AIM: To use a smartphone application (app) during pedicle screw placement navigation and examine the accuracy of this applicationon an anatomical dry vertebrae model.MATERIAL and METHODS: Seventy-six dry vertebrae were used for this study, and pedicle entry points and projections ofpedicle screw trajectory lines in the lateral and superior aspects of the vertebral body were identified and drawn for each vertebrabilaterally. In each position, all angulations were measured directly before the procedure manually. One hundred and fifty two pediclescrews were inserted as a simulation of screw placement with the guidance of the angle-meter smart app. Accuracy of the methodwas tested according to the occurrence of bone penetration while the angular deviation of the inserted screws was evaluated incomputed tomography images.RESULTS: The mean deviation for 76 pedicle screws on the right side was 2.30°±1.78° in the horizontal plane and 2.17°±1.57° inthe sagittal plane; and on the left side, 3.01°±1.83° in the horizontal plane and 2.38°±1.68° in the sagittal plane. No bone penetrationoccurred during 152 pedicle screw placements. According to the t-test results, there were significant differences between the twogroups in the craniocaudal direction of the right side pedicle screws and in the craniocaudal direction of left sided pedicle screws.CONCLUSION: The free smartphone app presented here as an angle-meter is a safe digital device for spinal instrumentationprocedures. As a prototype of future pedicle screw fixation systems, it should be improved in terms of its feasibility and compatibilitywith screw probes. This may lead to a useful mobile digital angle-meter for spinal procedures.