Surgical Management of Congenital Vertebral Malformations in Small Animals: Outcomes and Future Directions

Document Type : Review article

Authors
Mohsen Vahar 1
Mostafa Kami 2
1 Board-certified Veterinary Surgeon, Faculty of Veterinary Medicine, Tehran University, Tehran, Iran
2 Doctor of Veterinary Medicine, Department of Clinical Sciences, Bab.C., Islamic Azad University, Babol, Iran
10.61882/eltiamj.12.1.8
Abstract
Background: Congenital vertebral malformations, particularly hemivertebrae, are prevalent in screw-tailed dog breeds such as French Bulldogs, English Bulldogs, and Pugs, with thoracic hemivertebrae reported in more than 93% of neurologically normal French Bulldogs, often without neurological signs. These malformations can cause myelopathy, presenting as ataxia, paresis, or urinary and/or fecal incontinence, often in the first year of life. While many cases are subclinical, severe kyphosis can result in deficits requiring advanced diagnostics and treatment.
Objectives: To evaluate the diagnostic methods, surgical techniques, and therapeutic outcomes for managing congenital vertebral malformations in small animals, with a focus on stabilization techniques and their impact on clinical improvement, and to explore future directions for reducing disease incidence.
Methods: A review study based on published sources on vertebral anomalies from reputable national and international journals and conferences.
Results: CT and MRI are key tools for comprehensive preoperative evaluation, with CT excelling in bony malformation assessment and MRI in spinal cord evaluation. Medical therapy yielded poor long-term outcomes, with progression of neurological signs in most cases. Surgical stabilization, with or without decompression, improved clinical signs in most dogs, with techniques like biological in situ fusion showing promise in non-ambulatory dogs, achieving ambulation without metallic implants. Cobb angles >35° predicted neurological signs with 75% positive predictive value. Selective breeding and early screening were proposed to reduce malformation incidence.
Conclusions: Surgical stabilization is the best therapeutic option for congenital vertebral malformations in small animals, providing better results than medical management by halting or reversing neurological decline. Advanced imaging is essential for surgical planning. Future efforts should focus on developing standardized grading systems, selective breeding, and early radiographic screening to mitigate disease prevalence and severity.

Keywords

Subjects

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Eltiam
Volume 12, Issue 1 - Serial Number 23
November 2025
Pages 128-134

  • Receive Date 18 August 2025
  • Accept Date 16 October 2025
  • Publish Date 22 November 2025