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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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