Use of custom 3D-modeled guides for the treatment of lumbosacral stenosis in dogs

Abstract

A method of treating lumbosacral stenosis in dogs using 3D-modeled guiding templates is discussed. Four dogs with confirmed lumbosacral stenosis, of middle age, including German Shepherds and mixed-breed dogs, without contraindications to general anesthesia and exhibiting characteristic clinical signs, underwent dorsal laminectomy and stabilization of the seventh lumbar (L7) and first sacral (S1) segments (L7 - the last lumbar vertebra; S1 - the first sacral vertebra) using a transpedicular fixation system assisted by 3D-modeled guides. The final diagnosis in all cases was made based on magnetic resonance imaging (MRI). Within the same general anesthesia session, computed tomography (CT) was performed to obtain the data required for guide modeling in the 3D software BonaPlanner v1.1.0. The guides were printed on an Anycubic Photon M3 Max 3D printer using Harz Labs Dental Clear Pro photopolymer resin. Surgical treatment using 3D-modeled guides was successful in three of the four dogs. In one dog, the heads of the transpedicular screws were too large to be placed strictly parallel; therefore, one of the screws in the lumbar vertebra had to be inserted more caudally. This did not affect the stability of the construct but extended the duration of the surgical procedure. Following surgical treatment of lumbosacral stenosis using 3D modeling technology, all dogs recovered well, without difficulties rising or signs of pain. The results suggest that the use of 3D-modeled guides may reduce the time required for dorsal laminectomy and L7-S1 transpedicular stabilization, as well as decrease the degree of tissue trauma due to more precise screw placement.