» Articles » PMID: 35189892

The Accuracy and Effectiveness of Automatic Pedicle Screw Trajectory Planning Based on Computer Tomography Values: an in Vitro Osteoporosis Model Study

Overview
Publisher Biomed Central
Specialties Orthopedics
Physiology
Date 2022 Feb 22
PMID 35189892
Authors
Affiliations
Soon will be listed here.
Abstract

Background: Pedicle screw placement in patients with osteoporosis is a serious clinical challenge. The bone mineral density (BMD) of the screw trajectory has been positively correlated with the screw pull-out force, while the computer tomography (CT) value has been linearly correlated with the BMD. The purpose of this study was to establish an in vitro osteoporosis model and verify the accuracy and effectiveness of automated pedicle screw planning software based on CT values in this model.

Methods: Ten vertebrae (L1-L5) of normal adult pigs were randomly divided into decalcification and control groups. In the decalcification group, the vertebral bodies were decalcified with Ethylenediaminetetraacetic acid (EDTA) to construct an in vitro osteoporosis model. In the decalcification group, automatic planning (AP) and conventional manual planning (MP) were used to plan the pedicle screw trajectory on the left and right sides of the pedicle, respectively, and MP was used on both sides of the control group. CT values of trajectories obtained by the two methods were measured and compared. Then, 3D-printed guide plates were designed to assist pedicle screw placement. Finally, the pull-out force of the trajectory obtained by the two methods was measured.

Results: After decalcification, the BMD of the vertebra decreased from - 0.03 ± 1.03 to - 3.03 ± 0.29 (P < 0.05). In the decalcification group, the MP trajectory CT value was 2167.28 ± 65.62 Hu, the AP trajectory CT value was 2723.96 ± 165.83 Hu, and the MP trajectory CT value in the control group was 2242.94 ± 25.80 Hu (P < 0.05). In the decalcified vertebrae, the screw pull-out force of the MP group was 48.6% lower than that of the control group (P < 0.05). The pull-out force of the AP trajectory was 44.7% higher than that of the MP trajectory (P < 0.05) and reached 97.4% of the MP trajectory in the control group (P > 0.05).

Conclusion: Automatic planning of the pedicle screw trajectory based on the CT value can obtain a higher screw pull-out force, which is a valuable new method of pedicle screw placement in osteoporotic vertebre.

Citing Articles

A user-friendly system for identifying the optimal insertion direction and to choose the best pedicle screws for patient-specific spine surgery.

Magliano A, Naddeo F, Naddeo A Heliyon. 2024; 10(4):e26334.

PMID: 38404767 PMC: 10884480. DOI: 10.1016/j.heliyon.2024.e26334.


Biomechanical evaluation of a novel minimally invasive pedicle bone cement screw applied to the treatment of Kümmel's disease in porcine vertebrae.

Ma X, Feng Q, Zhang X, Sun X, Lin L, Guo L Front Bioeng Biotechnol. 2023; 11:1218478.

PMID: 37476480 PMC: 10354293. DOI: 10.3389/fbioe.2023.1218478.

References
1.
Lehman Jr R, Polly Jr D, Kuklo T, Cunningham B, Kirk K, Belmont Jr P . Straight-forward versus anatomic trajectory technique of thoracic pedicle screw fixation: a biomechanical analysis. Spine (Phila Pa 1976). 2003; 28(18):2058-65. DOI: 10.1097/01.BRS.0000087743.57439.4F. View

2.
Cody D, Gross G, Hou F, Spencer H, Goldstein S, Fyhrie D . Femoral strength is better predicted by finite element models than QCT and DXA. J Biomech. 1999; 32(10):1013-20. DOI: 10.1016/s0021-9290(99)00099-8. View

3.
Rho J, Hobatho M, Ashman R . Relations of mechanical properties to density and CT numbers in human bone. Med Eng Phys. 1995; 17(5):347-55. DOI: 10.1016/1350-4533(95)97314-f. View

4.
Carter D, Hayes W . The compressive behavior of bone as a two-phase porous structure. J Bone Joint Surg Am. 1977; 59(7):954-62. View

5.
Goerres J, Uneri A, De Silva T, Ketcha M, Reaungamornrat S, Jacobson M . Spinal pedicle screw planning using deformable atlas registration. Phys Med Biol. 2017; 62(7):2871-2891. PMC: 9148916. DOI: 10.1088/1361-6560/aa5f42. View