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25                 Vertebral Fracture and Luxation





                                  Repair




               Bianca Hettlich




               Introduction                                       the  extent of injury and allow familiarization with the anatomy
               Vertebral column injuries are typically the result of high‐impact   around the injury and patient‐specific landmarks. Decisions must
               trauma  such as  vehicular  accidents  or falls from  heights.  While   be made regarding the type of implant, number of implants, and
               trauma can be sustained via bite wounds, projectiles and crushing   unilateral or bilateral placement. If the type of implant allows, indi­
               injuries, fractures and luxations most often occur due to tremen­  vidual implant insertion angles should be measured for each verte­
               dous compression forces, rotation, hyperflexion or hyperextension   bra and each implant to allow for maximum bone purchase, while
               (Figure 25.1). The need for surgical stabilization is based on the   assuring a safe implant corridor (Figure 25.3).
               degree of vertebral column instability and spinal cord compression.
               Injury to the intervertebral disc, articular processes, vertebral body,
               and associated ligamentous structures will have differing impact on  Decompression in Addition to Stabilization
               the stability of the spine.                        At times, it is necessary to access the vertebral canal to address com­
                 The three‐compartment concept can be applied to guide deci­  pression by hematomas, traumatic disc extrusions, and displaced
               sion‐making after vertebral trauma [1]. With this concept the   bone fragments. The type of approach depends on the location of
               vertebra is divided into dorsal, middle and ventral compart­  the inciting compression. For the cervical spine, a ventral slot can
               ments that comprise (i) spinous process, dorsal ligamentous   be performed through the same approach as for ventral stabiliza­
               structures, lamina, articular processes, and pedicles; (ii) dorsal   tion; however, it is limited in the amount of exposure to the verte­
               longitudinal ligament, dorsal annulus fibrosus, dorsal aspect of   bral canal it provides. A separate approach for a dorsal laminectomy
               the vertebral body, and transverse processes; and (iii) remaining   is possible, but must be carefully considered due to the need for a
               vertebral body and annulus fibrosus, nucleus pulposus, and ven­  second major surgical approach. For thoracolumbar trauma, it is
               tral longitudinal ligament (Figure 25.2). Injury to two or more   common to perform a hemilaminectomy, mini‐hemilaminectomy
               compartments is generally considered unstable. Apart from   (sparing the articular processes), or partial pediculectomy in con­
               assessing stability and spinal cord compression, the decision to   junction with vertebral column  stabilization if compression is
               pursue vertebral column stabilization has to consider the   located ventrally or ventrolaterally. If a dorsal laminectomy is
               patient’s neurological status, chronicity of injury, and concur­  required  for  dorsal  compression,  articular  processes  should  be
               rent injuries.                                     spared if possible to avoid further destabilization of the affected
                                                                  vertebral articulation.
                                                                    Lumbosacral fractures or luxations can be decompressed via dor­
               Preoperative Planning                              sal laminectomy while sparing the articular facets and because
               Preoperatively,  standard  orthogonal  radiographic  views  of  the   these can be challenging to reduce, a concurrent dorsal laminec­
               affected vertebral column are used to assess the type and location of   tomy may be of benefit to offset compression secondary to
               the vertebral column injury. Radiographs will help determine   malalignment.
               whether the immediate vertebrae can be utilized for fixation (i.e., in   Protection of exposed spinal cord or nerve roots during applica­
               case of vertebral column luxation) or if instrumentation needs to be   tion of polymethylmethacrylate (PMMA) can be achieved by using
               applied to adjacent vertebrae (i.e., in case of vertebral fracture).   celluloid sponges and molding cement away from the laminectomy
               A  preoperative CT scan should be performed to better identify   site with Freer elevators. While accessing the vertebral canal in such


               Current Techniques in Canine and Feline Neurosurgery, First Edition. Edited by Andy Shores and Brigitte A. Brisson.
               © 2017 John Wiley & Sons, Inc. Published 2017 by John Wiley & Sons, Inc.
               Companion website: www.wiley.com/go/shores/neurosurgery



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