ABSTRACT Purpose: This study compared, through biomechanical evaluation under ventral flexion load, four surgical techniques for ventral stabilization of the atlantoaxial joint in dogs. Methods: In total, 28 identical atlantoaxial joint models were created by digital printing from computed tomography images of a dog, and the specimens were divided into four groups of seven. In each group, a different technique for ventral stabilization of the atlantoaxial joint was performed: transarticular lag screws, polyaxial screws, multiple screws and bone cement (polymethylmethacrylate–PMMA), and atlantoaxial plate. After the stabilization technique, biomechanical evaluation was performed under ventral flexion load, both with a predefined constant load and with a gradually increasing load until stabilization failure. Results: All specimens, regardless of stabilization technique, were able to support the predefined load without failing. However, the PMMA method provided significant more rigidity (p ≤ 0.05) and also best resisted the gradual increase in load, supporting a significantly higher maximum force (p ≤ 0.05). There was no statistical difference in flexural strength between the transarticular lag screws and plate groups. The polyaxial screws method was significantly less resistant to loading (p ≤ 0.05) than the other groups. Conclusions: The PMMA technique had biomechanical advantages in ventral atlantoaxial stabilization over the other evaluated methods.

RESUMO: Um cão macho, da raça Terrier Brasileiro de seis meses de idade, com dispnéia e tosse persistente foi diagnosticado com colapso traqueal intratorácico e pneumonia após estudo radiográfico de tórax. Foi instituído tratamento médico e realizada toracotomia para a implantação de prótese traqueal extraluminal de nitinol. O animal não manifestou dispneia ou pneumonia durante os quatro anos posteriores ao procedimento. A implantação da prótese extraluminal através da toracotomia foi eficaz para o tratamento do colapso traqueal intratorácico, sem provocar danos estruturais na região torácica. Desta forma, este é primeiro relato da utilização bem-sucedida deste tipo de prótese, a partir da abordagem intercostal, no tratamento de cães com colapso traqueal intratorácico.

ABSTRACT: A six-month-old male Brazilian Terrier with persistent cough and dyspnea was diagnosed with intrathoracic tracheal collapse and pneumonia after chest radiographics. The medical treatment was performed, and an extraluminal nitinol prosthesis was placed through thoracic access. The dog did not presented recurrence of dyspnea or pneumonia for four years after the surgical procedure. Placement of the extraluminal prosthesis with the thoracic approach effectively stabilized intrathoracic tracheal collapse without causing any structural damage in the thoracic region. Therefore, this is the first report of a successful use of this prosthesis with an intercostal approach in dogs for intrathoracic trachea collapse.

ABSTRACT Purpose To investigate the applicability of piezosurgery for cervical ventral slot (CVS), comparing it with the conventional technique of using high-speed burs for bone wear. Methods Thirty rabbits (Oryctolagus cuniculus) were divided into two treatment groups (T1 and T2) corresponding to CVS between C3-C4. In T1, the surgery was performed with piezoelectric apparatus, and in T2 with high-speed burs. The evaluated parameters were: duration of each stage of surgery, temperature variations during CVS, visibility of the surgical field, intra and postoperative complications, and anesthetic monitoring. At 14, 28, and 56 postoperative days, five animals from each treatment group were submitted for histopathological study of the surgical site. Results Compared with T2, T1 had more precise bone cut, and better visibility of the operative field, although it required longer total surgical time (p = 0.02) and triggered a greater number of intraoperative complications (p < 0.01), microscopic lesions in the spinal cord (p < 0.05), and transient neurological deficits in the postoperatively (p < 0.05). Conclusions It is necessary to perform surgical planning and have several tips of the piezoelectric instrument available for the safe use of the piezoelectric device in neurosurgery.