PDF icon Download PDF
Vet Comp Orthop Traumatol 2021; 34(05): 338-345
DOI: 10.1055/s-0041-1731808
Original Research

Accuracy and Safety of Image-Guided Freehand Pin Placement in Canine Cadaveric Vertebrae

Eva S. Samer 
1   Department of Clinical Veterinary Medicine, Division of Clinical Neurology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
,
Franck Forterre 
2   Department of Clinical Veterinary Medicine, Division of Small Animal Surgery, Vetsuisse Faculty, University of Bern, Bern, Switzerland
,
Justus M.K. Rathmann
3   Institute of Sociology, University of Zurich, Zurich, Switzerland
,
Veronika M. Stein
1   Department of Clinical Veterinary Medicine, Division of Clinical Neurology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
,
Christina M. Precht
4   Department of Clinical Veterinary Medicine, Division of Clinical Radiology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
,
Julien Guevar 
1   Department of Clinical Veterinary Medicine, Division of Clinical Neurology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
› Author Affiliations
› Further Information
Also available atVetCenter
   Permissions and Reprints
Preview

Abstract

Objective The aim of this study was to validate an imaging technique for evaluation of spinal surgery accuracy and to establish accuracy and safety of freehand technique in the thoracolumbar spine of large breed dogs.

Study Design After thoracolumbar spine computed tomography (CT), 26 drilling corridors were planned then drilled to receive 3.2 mm positive profile pins using a freehand technique. After pin removal, CT was repeated. All entry points, exit points and angles of the preoperative planned trajectories were compared with postoperative ones using an image registration and fusion technique by three observers. Corridor coordinates for entry and exit points were evaluated in three dimensions and angles were measured in one plane. Intraclass correlation coefficient (ICC) was used to establish the imaging technique reliability and descriptive statistics were used to report on the freehand technique accuracy. Safety was evaluated using a vertebral cortical breach grading scheme.

Results Intraclass correlation coefficient for the entry points, exit points and angle were 0.79, 0.96 and 0.92 respectively. Mean deviations for the entry points, exit points and angle were 3.1 mm, 6.3 mm and 7.6 degrees respectively. Maximum deviations were 6.3 mm, 11.0 mm and 16.4 degrees. Most deviations were lateral and caudal. All corridors were judged as safe.

Conclusion The imaging technique reliability was good to excellent to study spinal surgery accuracy. Implant deviations should be anticipated when planning stabilization surgery in large breed dogs using the freehand-guided technique.

Keywords

dog - freehand - spinal surgery - stabilization - accuracy

Authors' Contributions

J.G. and E.S. executed the experiments and registered the data. J.R. did statistical analysis. J.G., E.S., F.F., J.R., C.P. and V.S. interpreted and critically revised the manuscript for important intellectual contribution. All the authors approved the final version.




Publication History

Received: 29 September 2020

Accepted: 08 June 2021

Article published online:
23 July 2021

© 2021. Thieme. All rights reserved.

Georg Thieme Verlag KG
Rüdigerstraße 14, 70469 Stuttgart, Germany