Thoracolumbar Spinal Stabilization with Three Dimensional-Printed Drill Guides and Pre-Contoured Polyaxial Bone Plates

Abstract

Objective The aim of this study was to report new preoperative and intraoperative techniques performed for canine thoracic or lumbar spine kyphosis stabilization using three-dimensional-printed patient-specific drill guides, polyaxial titanium bone plates and drill stops, and to determine the accuracy of screw placement using these techniques.

Study Design Retrospective study, five client-owned dogs.

Results Three-dimensional-printed patient-specific drill guides and drill stops allowed safe drilling and screw placement in all of the cases, with (i) 84% of the screws graded as I (ideal placement) and 16% as IIa, IIIa or IIIb according to the modified Zdichavsky classification (partial penetration of medial pedicle wall, partial penetration of lateral pedicle wall and full penetration of lateral pedicle wall respectively), (ii) mean mediolateral deviation of ± 4.06 degrees (standard deviation: 8.21 degrees) compared to planned trajectories and (iii) variation in screw depth of ± 2.29mm (standard deviation: 3.07mm) compared to planned depth.

Conclusion We believe that the techniques presented here for thoracic spinal stabilization in dogs show promise; they allowed safe placement of screws along planned trajectories and depth; they also removed the need to use polymethylmethacrylate, while the use of titanium offers the possibility to repeat magnetic resonance imaging in these cases with chronic spinal conditions.

Keywords

spine - 3D-printed drill guide - polyaxial titanium plate - drill accuracy - dogs

Authors' Contributions

O.G. contributed with conceptualization, study design, data acquisition, data interpretation and analysis, drafting and revising the manuscript. L.E. and D.O., H.V., D.R., and B.O. took part in data acquisition, and drafting and revising the manuscript. N.G. contributed with conceptualization, study design, data acquisition, data interpretation and analysis, drafting and revising the manuscript. All authors approve the submitted manuscript and are publicly accountable for relevant content.

Publication History

Received: 06 December 2021

Accepted: 02 July 2022

Article published online:
22 November 2022

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