Development of a patient specific 3D-printed drill guide for ventral slot surgery in dogs

Spinal cord decompression via ventral slot is considered the treatment of choice for cervical intervertebral disc extrusion in dogs. Complications of the ventral slot procedure include vertebral instability and subluxation secondary to excessive slot width. Achieving appropriate dimensions intraoperatively can be difficult due to patient size, size of available equipment, and experience of the surgeon. The objectives of this study are to develop a patient-specific 3Dprinted drill guide that will improve the accuracy of the creation of ventral slots for spinal cord decompression in dogs with cervical intervertebral disc disease. In this ex vivo study, cervical computed tomography (CT) was performed on 8 canine cadavers and images were used to create patient-specific drill guides to achieve appropriate ventral slot dimensions. Vertebral models and drill guides were 3D-printed, and utility was subjectively assessed by the investigators. Ventral slot procedures will be performed on cadavers with and without drill guides (n=24) by a novice surgeon and slot length, slot width, slot shape, and deviation from midline will be assessed based on post-operative CT. Statistical analyses will be performed to compare dimensions of ventral slots achieved with and without a drill-guide.