Biomechanical effects of kyphoplasty-assisted versus traditional bone cement augmentation on the loosened sacral screws
10.3969/j.issn.1673-8225.2011.48.016
- VernacularTitle:后凸成形和传统钉道骨水泥强化对骶骨钉松动的生物力学作用
- Author:
Dongchang ZHOU
;
Libing WANG
;
Liwen ZENG
;
Yangliang HUANG
;
Binsheng YU
- Publication Type:Journal Article
- From:
Chinese Journal of Tissue Engineering Research
2011;15(48):8993-8997
- CountryChina
- Language:Chinese
-
Abstract:
BACKGROUND: Kyphoplasty-assisted bone cement augmentation can be used in lumbar pedicle screw fixation of osteoporotic patients.OBJECTIVE: To assess the fixation strengths of loosened sacral screws augmented with kyphoplasty-assisted and traditional bone cement techniques.METHODS: Fresh sacra were harvested from nine osteoporotic cadavers. After testing bilaterally placed unicortical and bicortical pedicle screws, two unicortical pedicle screws with the traditional and kyphoplasty-assisted cement augmentations were established on the same sacrum. Following 2000 cyclic compression loading to screw head on a MTS machine, their maximum pull-out forces were recorded and compared. RESULTS AND CONCLUSION: The bone mineral densities of nine specimens were ranged from 0.61 to 0.77 g/cm2 (0.71 g/cm2 in average). The mean maximum pull-out forces of unicortical and bicortical screws, and traditional and kyphoplasty-assisted cement screws were 203, 325, 437, and 565 N, respectively. The pull-out force was significantly higher in bicortical screw compared with unicortical (P < 0.05); however, these two fixations exhibited markedly lower pull-out strength compared with two cement augmentation techniques (P < 0.05). The pull-out strength was significantly higher in kyphoplasty-assisted cement augmentation group compared with traditional bone cement technique (P < 0.05). In addition, a significant positive correlation was exhibited between bone mineral density and pull-out force for the four fixations (P < 0.05). Results demonstrated that traditional and kyphoplasty-assisted cement augmentations can serve as the salvage technique for loosening sacral screw. However, kyphoplasty-assisted augmentation can provide higher stability.
