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16 Dorsal Cervical Decompression

(Laminectomy/Hemilaminectomy

and Laminotomy)

James M. Fingeroth

Introduction Indications for Dorsal Decompression
The choice of surgical approach to the vertebral canal, dural of the Cervical Spine
tube, spinal cord, and nerve roots is largely predicated on the As addressed in Chapter 17, ventral approaches to the cervical
circumferential location of the targeted pathology and the nature vertebral canal are limited in most instances to relatively short nar-
of that pathology. The goals when making such a surgical row “slots” between adjacent vertebrae. The chief indication for
approach are to gain access to the lesion in a manner that simul- such an approach is to effect decompression of the spinal cord and
taneously maximizes the visualization and ability to treat the nerve roots from intervertebral disc herniations that occur centrally
lesion (i.e., achieve mass removal and effectively decompress the or just parasagittally within the vertebral canal. Ventral approaches
spinal cord and nerve roots, debulk or biopsy lesions, etc.), are also used for many of the stabilizing procedures (with or with-
while minimizing the need for manipulation and potential iatro- out partial or complete “slots”) in the treatment of spondylomye-
genic trauma to neurovascular structures and minimizing insta- lopathy (see Chapter 17), and for placement of disc prostheses or
bility of the spinal motion segment and risk of resultant fracture other implants. For disc lesions more lateralized within an interver-
or luxation. tebral foramen, or for nondisc‐related lesions such as tumors, and
The cervical vertebral canal is more amenable to ventral in some cases of spondylomyelopathy, ventral approaches are usu-
approaches than the thoracic or lumbar portions of the verte- ally insufficient, and dorsal (or dorsolateral) approaches are utilized
bral column in dogs and cats. And while such ventral [1–3]. Some advocate the use of dorsal approaches as well for ven-
approaches are infrequently utilized caudal to the cervical trally or ventrolaterally herniated discs, even though this may vio-
region in domestic animals, they are commonly employed in late one of the cardinal principles listed above, namely to minimize
the cervical region. Therefore, the veterinary surgeon has more spinal cord manipulation and potential for iatrogenic spinal cord
options in his or her approach to the cervical vertebral canal; injury. This controversy is again addressed elsewhere [4–8]. For the
however, there is also the burden of selecting the optimum treatment of other lesions, a dorsally or laterally based approach is
approach, based on the principles above and published results the only effective way to adequately expose the lesion and permit
from the literature. the manipulations required for treatment.
Controversy exists with regard to the choice between ventral and
dorsal approaches for the treatment of cervical intervertebral disc
herniation and for the spectrum of diseases categorized under the Laminectomy versus Hemilaminectomy
heading of caudal cervical spondylomyelopathy syndrome (so‐ The term “laminectomy” or “dorsal laminectomy” is frequently
called “wobbler syndrome”). Some of this controversy and the basis used to describe the complete removal of the bony lamina, whereas
for choosing a particular surgical technique are summarized in a the term “hemilaminectomy” implies a more lateralized approach
contemporary text [1]. In this chapter I will address the main indi- that preserves some portion of the lamina and the entire articular
cations for a dorsally based approach, and the specifics of the facet on the contralateral side and usually entails at least partial
involved surgical procedures. removal of the articular facet on the operative side. Often with

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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