Accuracy of Pedicle Screw Placement in Scoliosis Surgery: A Comparison between Conventional Computed Tomography-Based and O-Arm-Based Navigation Techniques

Kotani, Toshiaki; Akazawa, Tsutomu; Sakuma, Tsuyoshi; Koyama, Kayo; Nemoto, Tetsuharu; Nawata, Kento; Yamazaki, Atsuro; Minami, Shohei

Abstract

STUDY DESIGN: Retrospective study. PURPOSE: We compared the accuracy of O-arm-based navigation with computed tomography (CT)-based navigation in scoliotic surgery. OVERVIEW OF LITERATURE: No previous reports comparing the results of O-arm-based navigation with conventional CT-based navigation in scoliotic surgery have been published.
METHODS
A total of 222 pedicle screws were implanted in 29 patients using CT-based navigation (group C) and 416 screws were implanted in 32 patients using O-arm-based navigation (group O). Postoperative CT was performed to assess the screw accuracy, using the established Neo classification (grade 0: no perforation, grade 1: perforation <2 mm, grade 2: perforation > or =2 and <4, and grade 3: perforation > or =4 mm).
RESULTS
In group C, 188 (84.7%) of the 222 pedicle screw placements were categorized as grade 0, 23 (10.4%) were grade 1, 11 (5.0%) were grade 2, and 0 were grade 3. In group O, 351 (84.4%) of the 416 pedicle screw placements were categorized as grade 0, 52 (12.5%) were grade 1, 13 (3.1%) were grade 2, and 0 were grade 3. Statistical analysis showed no significant difference in the prevalence of grade 2.3 perforations between groups C and O. The time to position one screw, including registration, was 10.9+/-3.2 minutes in group C, but was significantly decreased to 5.4+/-1.1 minutes in group O.
CONCLUSIONS
O-arm-based navigation facilitates pedicle screw insertion as accurately as conventional CT-based navigation. The use of O-arm-based navigation successfully reduced the time, demonstrating advantages in the safety and accuracy of pedicle screw placement for scoliotic surgery.