The Journal of Bone and Joint Surgery, Vol 73, Issue 4 527-534, Copyright © 1991 by Journal of Bone and Joint Surgery, Inc
Anterior spinal fixation after lumbar corpectomy. A study in dogs
TA Zdeblick, O Shirado, PC McAfee, H deGroot and KE Warden
Department of Orthopedic Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland 21239.
An animal model was developed to simulate an unstable lumbar burst fracture
that had been treated with corpectomy. A fifth lumbar laminectomy, partial
facetectomy, and corpectomy was performed in twenty-one dogs. In seven dogs
(the control group), a biodegradable polymer spacer was used to create a
definite failure of fusion (Group I). Seven dogs were treated with a
traditional anterior arthrodesis with an autogenous ulnar strut and without
instrumentation (Group II). The remaining seven dogs were treated with an
ulnar strut and anterior Kaneda instrumentation that was of an appropriate
size for the dog (Group III). At twenty-four weeks, the results were
analyzed in terms of the rate of fusion, biomechanical rigidity,
neuropathological findings, and histomorphometric data on the vertebral
response. The rate of fusion was significantly higher in Group III, in
which the Kaneda device had been used, than it was in either Group I or
Group II, in which instrumentation had not been used. Biomechanically, the
spines in Group III were stiffer in torsion than those in Group I or II.
There was no difference between groups in terms of the number of
neuropathological changes in the spinal cord. Histomorphometric analysis
showed that no meaningful device-related osteopenia occurred in the
vertebrae that were spanned by the fixation device. Trabecular density was
increased in the vertebrae in which the instrumentation was anchored.
CiteULike 
Connotea 
Del.icio.us 
Technorati What's this?
