A comparative study on biomechanical results of posterior mono-segment pedide instrumentationand its combination with bone cement fixation for management of thoracolumbar fractures
10.3760/cma.j.issn.1001-8050.2009.01.13
- VernacularTitle:胸腰椎骨折后路单节段椎弓根钉固定与结合骨水泥强化固定的生物力学比较
- Author:
Guangxun HU
;
Weihong YI
;
Fuxin WEI
;
Tong SHA
;
Bailing CHEN
;
Shaoyu LIU
- Publication Type:Journal Article
- Keywords:
Spinal fractures;
Thoracic vertebrae;
Lumbar vertebrae;
Fracture fixation,internal;
Biomechanics;
Bone cement fixation
- From:
Chinese Journal of Trauma
2009;25(1):36-40
- CountryChina
- Language:Chinese
-
Abstract:
Objective To compare the biomechanical properties of mono-segTnent pedicle instru-mentation and its combination with bone cement fixation in treatment of thoracolumbar fractures. Meth-ods Eight fresh specimens of calf spines ( T11 -L3 ) were used for development of incomplete burst frac-ture models at the vertebral body of L1. Mono-segment pedicle instrumentation and its combination with vertebroplasty were respectively applied in each specimen subsequently to restore spinal stability. A cyclic loading with pure moment of 4 Nm was applied to specimens, with load frequency of 0.5 Hz for 2 000 cy-cles. Range of motion (ROM) at flexion/extension, left/right lateral bending and left/right axial rotation of the fixated segment at different status of intact, injury, fixation and cyclic loading was determined by spinal three-dimensional instability test system. Results ROM after treatment with two fixation tech-niques and that at different directions after cyclic loading were distinctly smaller than that of intact and fractured models (P <0.05 ). Under mono-segment pedicle instrumentation combined with bone cement fixation, ROM at flexion, extension, lateral bending and axial rotation was 0.40°, 0. 53°, 0.86° and 0.55° respectively and that after cyclic loading was 0.10°, 0.07°, 0.19° and 0.08°respectively, which were all lower than those of monosegmental fixation, especially at flexion and axial rotation, with statisti-cal difference (P <0.05 ). Conclusions Both fixation techniques can provide instant stabihty of the fractured spine and have good fatigue resistance effect. However, mono-segment pedicle instrumentation is inferior to mono-segment pedicle instrumentation plus bone cement fixation in treatment of fractured verte-bral body at flexion and axial rotation.
