Transthoracic Vertebral Distraction and Stabilization in 10 Dogs with Congenital Thoracic Vertebral Malformations

Abstract

Objective The aim of this study was to describe the surgical technique and outcomes of dogs with congenital thoracic vertebral body malformations (CTVBM) treated with unilateral vertebral distraction and stabilization with monocortical screws and polymethylmethacrylate (PMMA).

Study Design Medical records of 10 client-owned dogs with CTVBM were retrospectively searched for signalment, history, neurological examination, neurological grade based on the modified Frankel scale (MFS), diagnostic method, CTVBM location, Cobb's angle, and vertebral canal angle (VCA), surgical procedure, complications and long-term follow-up.

Results One dog suffered cardiac arrest 24 hours post-surgery and died. Median follow-up in nine dogs was 26.5 months (12–50 months). Cobb's angle improved from 33–83 to 10–46 degrees and the VCA ratio from 97–138 to 122–164 degrees. The MFS improved from 3 (n = 3)–4 (n = 7) to 4 (n = 2)–6 (n = 7). Seven dogs recovered full function. Nine dogs improved after surgery compared with preoperative status, recovering ambulation when lost or achieving normal neurological examination in seven cases. No complications were reported during the follow-up period (12–50 months).

Conclusion Unilateral transthoracic vertebral distraction and stabilization with monocortical screws and PMMA for treatment of compressive myelopathy due to CTVBM achieved long-term neurological improvement in 9 of 10 dogs.

Keywords

congenital vertebral body malformation - transthoracic - stabilization - distraction - dog

Note

A part of the clinical cases included in this study were presented in the 31st annual ECVN/ESVN symposium in Copenhagen, Denmark, September 20–22, 2018.

Authors' Contributions

A.F.M. was involved in drafting the work, acquisition, analysis and interpretation of data, final approval of the published version and agrees to be accountable for all aspects of the work. L.D.R. was involved in performing the surgery in some of the cases described, revising the intellectual content of the work, final approval of the published version and agrees to be accountable for all aspects of the work. J.M. was involved in performing the surgery in some of the cases described, revising the intellectual content of the work, final approval of the published version and agrees to be accountable for all aspects of the work. M.J.P. was involved in the surgical approach of some of the cases described, revising the intellectual content of the work, final approval of the published version and agrees to be accountable for all aspects of the work. M.L. was involved in the acquisition of data for the work, revising the intellectual content of the work, final approval of the published version and agrees to be accountable for all aspects of the work. F.S. was involved in the acquisition of data for the work, revising the intellectual content of the work, final approval of the published version and agrees to be accountable for all aspects of the work. A.L.F. was involved in performing the surgery in some of the cases described, conception and design of the work, revising the intellectual content of the work, final approval of the published version and agrees to be accountable for all aspects of the work.

Publication History

Received: 23 October 2020

Accepted: 08 June 2021

Article published online:
22 July 2021

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