[Biomechanical study of vertebroplasty with geneX(®) cement augmentation in a calf osteoporotic vertebral compression fracture model].
OBJECTIVE
To evaluate the biomechanical properties of geneX cements for use in vertebroplasty in a calf osteoporotic vertebral compression fracture model.


METHODS
Thirty vertebral bodies (T(9)-L(4)) were harvested from 4 fresh calf spines. The bone mineral density was measured with dual-energy radiographic absorption. Osteoporotic vertebral model was induced in each vertebra using decalcifying chemical agents, and was then compressed to determine their initial strength and stiffness before injecting the cement. Thirty vertebral bodies were divided randomly into geneX(®) cement group, CSC group, and PMMA group. The fractures were repaired using a transpedicular injection of cements and re-compressed to measure posttreatment strength and stiffness.


RESULTS
The normal mean BMD of the calf vertebra was 1.425∓0.072 g/cm(2), which was reduced significantly to 1.074∓0.065 g/cm(2) after decalcification. The mean injected volume was similar between geneX(®) (4.5∓0.7 ml), CSC (4.3∓0.8 ml) and PMMA (3.8∓0.4 ml) groups. The vertebral strength was restored after the treatment to 1198∓529 N in geneX(®) group, 1212∓430 N in CSC group and 1672∓704 N in PMMA group. All the cements produced significantly greater strength than the initial strength (P<0.05). The augmented strength in geneX(®) and CSC groups were similar (P>0.05), but both were significantly less than that in PMMA group (P<0.05). The stiffness in geneX(®), CSC, and PMMA groups was 233∓130, 242∓191, and 323∓145 N/mm, respectively, showing no significant difference between them (P>0.05). No significant difference was found in the augmented stiffness among the 3 cements (P>0.05).


CONCLUSIONS
geneX(®) cement is a useful alternative to PMMA in vertebroplasty for osteoporotic vertebral compression fractures, but further study is needed to evaluate its biosorption in vivo.
Department of Spinal and Orthopedic Surgery, Southern Medical University, Guangzhou, China. zhangshufang1983@126.com
Shufang
S
Zhang
Jianming
J
Jiang
Qingan
Q
Zhu
Zhiping
Z
Huang
D000818:Animals; D001696:Biomechanical Phenomena; D001843:Bone Cements / Q000627:therapeutic use*; D002417:Cattle; D004195:Disease Models, Animal; D050815:Fractures, Compression / Q000209:etiology / Q000601:surgery*; D008159:Lumbar Vertebrae / Q000293:injuries; D010024:Osteoporosis / Q000150:complications / Q000473:pathology; D013904:Thoracic Vertebrae / Q000293:injuries; D054854:Vertebroplasty
D001843:Bone Cements