Osseointegration of hollow cylinder based spinal implants in normal and osteoporotic vertebrae: a sheep study

Goldhahn, Jörg; Neuhoff, D; Schaeren, Stefan; Steiner, B; Linke, Berend; Aebi, Max; Schneider, Erich

doi:10.1007/s00402-006-0185-7

Cited by 23 publications

(17 citation statements)

References 34 publications

(32 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Sheep have been widely used as an animal model in orthopedic research (16), and as osteoporosis models in numerous studies (17)(18)(19). However, the time required to establish an accurate osteoporosis model remains inconsistent between studies.…”

Section: Discussionmentioning

confidence: 99%

Long-term effects of ovariectomy on the properties of bone in goats

Wang

Tang

et al. 2015

Experimental and Therapeutic Medicine

View full text Add to dashboard Cite

Abstract. Large animal models of osteoporosis are essential for osteoporosis research. However, the time required to establish an accurate osteoporosis model is unknown. Therefore, the aim of the present study was to establish a large animal model of osteoporosis in goats. In total, 14 Chinese goats were divided into an ovariectomized (OVX, n=7) or sham-operated (SHAM, n=7) group. Vertebral bodies were used to measure the bone mineral density (BMD) prior to the ovariectomy and at 24 months after the ovariectomy. In addition, the BMD of the femoral neck, femoral diaphysis and tibial diaphysis were measured 24 months postoperatively. Bone samples from the vertebral body, femoral head and femoral neck were scanned by micro-computed tomography (CT) to visualize the trabecular and cortical microstructure. Furthermore, the vertebral body, femoral head, femoral neck and tibial diaphysis were analyzed for mechanical strength. The BMD of vertebral body of the OVX group decreased significantly (P<0.01) at 24 months after the ovariectomy when compared with the baseline measurements. Micro-CT scans of the vertebral body revealed that the bone volume fraction, trabecular number, trabecular thickness and the degree of anisotropy decreased by 37.1, 36.7, 10.5 and 16.5%, respectively (P<0.01) in the OVX group when compared with the SHAM group. Additionally, the specific bone surface and trabecular spacing significantly increased by 37.7 and 62%, respectively in the OVX group (P<0.001). Cortical bone porosity in the vertebral body and femoral neck was greater in the OVX group when compared with the SHAM group (P<0.05). In addition, mechanical testing revealed a statistically significant difference between the vertebral bodies of the OVX group and the SHAM group. In conclusion, the present study demonstrated that an ovariectomy was able to induce significant osteoporosis and deterioration of mechanical properties in the bones of goats.

show abstract

Section: Discussionmentioning

confidence: 99%

Long-term effects of ovariectomy on the properties of bone in goats

Wang

Tang

et al. 2015

Experimental and Therapeutic Medicine

View full text Add to dashboard Cite

show abstract

“…[24] Results of one biomechanical animal study have demonstrated an association of mean tissue density and compressive strength of calf spines with a young healthy human spine. [25] Hence, in experimental study, animal spines are used as a substitute for human cadaveric specimens.…”

Section: Discussionmentioning

confidence: 99%

Efficacy of Dual Energy X-ray Absorptiometry for Evaluation of Biomechanical Properties: Bone Mineral Density and Actual Bone Strength

2014

View full text Add to dashboard Cite

IntroductionBone mineral density (BMD) is an important index in diagnosis of osteoporosis and other metabolic bone diseases, prediction of fractures, and monitoring treatment. This study was to find a more feasible technique for prediction of osteoporotic fracture between dual energy X-ray absorptiometry (DXA) and quantitative computed tomography (QCT) and to reveal the actual change of bone strength when BMD was changed.MethodsTen of these 20 specimens were used as the demineralized group and the other 10 as the control. Each specimen was immersed in HCl solution at for a period of at least 10 minutes, up to 100 minutes, at an interval of 10 minutes for different levels of demineralization. BMD was measured using DXA and QCT. Uniaxial compression tests were conducted to measure biomechanical parameters. Pearson correlation analysis was used respectively between BMD and biomechanical parameters and between DXA and QCT.ResultsElastic modulus (r=0.87) and yield stress (r=0.84) showed a statistically significant correlation with DXA BMD. Through correlation analysis with QCT BMD and elastic modulus, correlation coefficient showed hemi-vertebra (r=0.80) and trabecular (r=0.68). In yield stress, there was a statistically significant correlation in hemi-vertebra (r=0.87) and trabecular bone (r=0.84).ConclusionDXA is a current standard technique not only for diagnosis of osteoporosis but also for prediction of fracture risk compared to QCT. Actual decrease of bone strength was much greater than that of BMD by both DXA and QCT.

show abstract

“…Studying the osteoporosis related bone loss and instrumentation of osteoporotic vertebra is important in understanding bone mechanics and development of new and improved implant designs [8,11]. Access to consistent and high quality human cadaveric tissue is limited.…”

Section: Introductionmentioning

confidence: 99%

A demineralized calf vertebra model as an alternative to classic osteoporotic vertebra models for pedicle screw pullout studies

et al. 2007

View full text Add to dashboard Cite

Screws, clamps and other spinal instrumentation materials are tested using healthy animal and healthy human vertebrae, but the application of similar tests to an osteoporotic vertebra is generally neglected because of high costs and limited availability of high quality and consistent osteoporotic vertebrae. The objective of this study is to develop an in-vitro method to decrease the mineral content of an animal vertebra utilizing decalcifying chemical agents that alters the bone mineral density and some biomechanical properties to such an extent that they biomechanically mimic the osteoporotic spine. This study was performed on 24 fresh calf lumbar vertebrae. Twelve out of these 24 vertebrae were demineralized and the others served as control. A hole was opened in the pedicles of each vertebrae and the bone mineral density was measured. Each vertebra was then placed into a beher-glass filled with hydrochloric acid decalcifier solution. The decalcifier solution was introduced through the holes in the pedicles with an infusion pump. The vertebrae were then subjected to DEXA to measure post process BMD. Pedicle screws were introduced into both pedicles of each vertebrae and pullout testing was performed at a rate of 5 mm/min. The difference of BMD measurements between pre-and postdemineralizing process were also statistically significant (p \ 0.001). The difference of pullout loads between preand post-demineralizing process were also statistically significant (p \ 0.001). The acid demineralizing process may be useful for producing a vertebra that has some biomechanical properties that are consistent with osteopenia or osteoporosis in humans.

show abstract

Osseointegration of hollow cylinder based spinal implants in normal and osteoporotic vertebrae: a sheep study

Cited by 23 publications

References 34 publications

Long-term effects of ovariectomy on the properties of bone in goats

Long-term effects of ovariectomy on the properties of bone in goats

Efficacy of Dual Energy X-ray Absorptiometry for Evaluation of Biomechanical Properties: Bone Mineral Density and Actual Bone Strength

A demineralized calf vertebra model as an alternative to classic osteoporotic vertebra models for pedicle screw pullout studies

Contact Info

Product

Resources

About