A biomechanical, radiologic, and clinical comparison of outcome after multilevel cervical laminectomy or laminoplasty in the rabbit.
METHODS
A rabbit model was used to compare clinical outcome, radiographic changes, and biomechanical flexibility after cervical laminectomy and open-door laminoplasty.


OBJECTIVE
This study tested the hypothesis that radiographic changes and biomechanical flexibility could explain the differences in clinical outcome after cervical laminectomy and laminoplasty.


BACKGROUND
Although multilevel cervical laminoplasty is thought to have advantages over cervical laminectomy, clinical outcome studies have been contradictory, and no experimental study has examined the possible mechanisms for the differences after healing.


METHODS
Twenty-four New Zealand White rabbits were randomized into four groups: normal, sham, C3-C6 wide laminectomy, and C3-C6 open-door laminoplasty. Clinical, radiographic, and biomechanical data were collected and compared up to 3 months after surgery.


RESULTS
Laminectomy had a statistically significant poorer clinical outcome when compared with laminoplasty after 3 months of healing. Radiologic analysis showed statistically significant angular deformity in the laminectomy group compared with laminoplasty and control groups at 3 months. In contrast, biomechanical measures of flexibility, neutral zone, and range of motion showed only small differences between any of the groups at any time.


CONCLUSIONS
The presence of deformity, and not a change in flexibility, is responsible for the differences in clinical outcome observed after laminectomy compared with laminoplasty in this model.
Fields
M J
MJ
Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708-0281, USA.
Hoshijima
K
K
Feng
A H
AH
Richardson
W J
WJ
Myers
B S
BS
D000818:Animals; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging / Q000502:physiology / Q000601:surgery*; D005260:Female; D007796:Laminectomy / Q000379:methods*; D008297:Male; D023421:Models, Animal; D018583:Pliability; D011817:Rabbits; D011859:Radiography; D011897:Random Allocation; D016059:Range of Motion, Articular; D013123:Spinal Fusion / Q000379:methods*; D016896:Treatment Outcome; D016474:Weight-Bearing