Evaluation of Osteoporotic Vertebral Bone and Disc Degeneration Induced by Malnutrition during Growth Period: Biomechanical and Histomorphometrical Study / 체질인류학회지

The aim of the present study is to analyze the generation of osteoporotic vertebral bone induced by malnutrition during growth period and analyze its effects for disc degeneration, based on biomechanical and histomorphometrical study. Mechanical and histomorphological characteristics of lumbar vertebral bones and discs of rats with calcium free diet (CFD) were detected and tracked by using high resolution in-vivo micro-computed tomography (in-vivo micro-CT), finite element (FE) and histological analysis. Twenty female Sprague-Dawley rats (6 weeks old, approximate weight 170g) were randomly divided into two groups (CFD group: 10, NOR group: 10). The CFD group was maintained on a refined calcium-controlled semisynthetic diet without added calcium, to induce osteoporosis. All lumbars (L1~L6) were scanned by using in vivo micro-CT with 35 micrometer resolution at 0, 4, 8 weeks to track the effects of CFD on the generation of osteoporosis. The results of morphological characteristics showed that BV/TV, Tb.Th, Tb.N in CFD group were significantly decreased over time (p<0.05), while those in NOR group were statistically increased over time (p<0.05) in the most lumbars (L1~L6). We also investigated the contrary tendency in Tb.Sp and SMI, compared to the above results in each group. In the simulated compression test using FE models, the structural effective modulus of CFD group significantly decreased (p<0.05), whereas that of NOR group was statistically increased, depending on the measuring time (p<0.05). The present study observed remarkable histological changes of nucleus pulposus and annulus fibrous by water loss in CFD group, compared with NOR group. These findings indicated that calcium insufficiency was the main factor in the generation of osteoporosis and it induced lumbar vertebral disc degeneration. This study is a valuable experiment to firstly evaluate osteoporotic vertebral bone and disc degeneration induced by malnutrition during growth period from a biomechanical and histomorphometrical point of view.

Effect of Whole Body Vibration on Trabecular Bone in OVX Rats / 체질인류학회지

Previous studies showed that whole body vibration could prevent bone resorption and stimulate new bone formation. The aim of this study is to detect and track effect of whole body vibration for osteoporotic bone of OVX rats. 12 Female rats were used and allocated into 5 group, CON, SHAM, WBV 17, WBV 30 and WBV 45. Rats except SHAM group were ovariectomised to induce osteoporosis. Rats in WBV groups were stimulated whole body vibration at magnitude of 1 mm(peak-peak) and frequency 17 Hz, 30 Hz and 45 Hz, repectively, for 8 weeks (20 min, 5 days/week). The 4th lumbar in rats were scanned at a resolution of 35 micrometer at baseline, before stimulation, and 8 weeks by In-vivo Micro-CT. To detect and track changes of morphological characteristics in lumbar trabecuar bone of rats, structural parameters were measured and calculated from acquiring images. In the results, changes of structural characteristics of WBV group were smaller than those of CON group. Loss of quantity of trabecular bone in WBV 45 was the least. In contrast, that in WBV 17 was the biggest. These results showed that reasonable whole body vibration beneficially affected osteoporotic bones. In addition to, whole body vibration was likely to be substituted partly for drug treatment.