Empirical Study Of Compound Vibration Machine On Osteoporosis Prevention And Treatment

1 BackgroundsOsteoporosis is a common disease in middle- aged and old people,characterized by low bone mass and microarchitectural deterioration of bone tissue with a consequent increase in bone fragility and susceptibility to fracture.It was estimated that the people with osteoporosis had been more than 200 millions in the world,and there had been more than 84 millions patients in China.The major consequence of osteoporosis is osteoporotic fracture.Fracture of hip,which had obviously decreased activity and a high mortality,was thought as the most dangerous consequence in osteoporosis. With ageing and prolonging of life,the rate of osteoporotic fracture increased by 1% each year in the world.To deal with the problem,we had to seek more effective and convenient non-pharmacal ways for osteoporosis prevention and treatment.Bone quality and probability of non-trauma fall were the key factors of oseoporotic fracture.So the most effective way to prevention and treatment of osteoporosis was to improve bone quality or/and balance control.Many researches confirmed that high frequency(=30Hz),low level(＜1g) and short time(＜30minutes) mechanical vibration could regulate bone metabolism,inhibit bone absorption and promote bone formation.On the other hand,it also could increase muscle mass,and improve muscle force and be helpful in balance control.But the current researches still stayed in laboratory,because most of the vibration level in current researches was too large to accept by people for long time using.Our research was supported by natural science found of Guangdong province. And we had the intellectual property rights of compound vibration and compound vibration machine.The compound vibration was compound by special balance interruption and vertical whole-body-vibration(WBV).We hoped it could enhance the muscle function and balance control based on the bone formation situation of WBV, and gain the improvement of both bone quality and balance control.2 Objectives1.To evaluate the preventive effects of high frequency and low level compound vibration on ovariectomized SD rats;2.To evaluate the therapeutic effects of compound vibration on different months old SD rats with osteoporosis;3.To evaluate the effects of compound vibration machine for osteoporosis prevention and treatment,and provide evidences for the further research.3 Methods3.1 Osteoporosis prevention experimentSix groups of 4-months old SD female rats,of which 5 groups received ovariectomy (OVX) and one was sham OVX,were arranged randomly(n=8),including normal control group(NC,sham-OVX group),prevented control group(PC),vibration prevented group(VP) 1-4.The VP groups corresponded with four different vibrations respectively as following:vibration 135Hz-45Hz,0.05g-0.1g;vibrationⅡ35Hz-45Hz, 0.12g-0.21g;vibrationⅢ45Hz-55Hz,0.05g-0.1g;vibrationⅣ45Hz-55Hz, 0.12g-0.21g.The intervention lasted 13 weeks with 20minutes/d and 5days/week from wound healing.There were some parameters to be compared bet-ween groups, such as BMD,time of forced swimming,bone microarchitecture,bone biomechanical character,serum bone turnover marker,the ratio and cross section area(CSA) of gast-rocnemius fibra types,area,OD and IOD values of myoceptor,et al.3.2 Osteoporosis treatment experiment24 SD female rats of 4.5-months old were divided into three groups randomly: young control group(YC),young treated group(YT) 1 and 2.And two random groups of 8 SD multiparous rats with 13-months named as old control group(OC) and old treated group(OT).The intervention began when osteoporosis occurred in these rats.The better two vibrations in the former would be used in young groups,and the best one used in old group.The experiment time and the comparisons between groups were as same as prevention experiment.4 Results4.1 Osteoporosis prevention experimentCompared with NC,The rats of PC changed a lot resulted from ovariectomy. Something increased significantly including weight(P=0.000),the ratio of gastroc-nemius fibra typeⅡa(P=0.033) andⅡb(P=0.000).The other things decreased or dete-riorated significantly,including lumbar BMD(P=0.000),bone microarchitecture, lumbar ultimate strength(P=0.008),weight ratio of gastrocnemius and body,proportion(P=0.000) and CSA(P=0.001) of gastrocnemius fibra typeⅠ,swimming time (P=0.047),OD(P=0.001) and IOD(P=0.014) of myoceptor.VP4 showed that body weight increased significantly(P=0.017) and bone micro-architecture improved significantly compared with PC.VP3 and VP4 got a significant gain in lumbar BMD(P=0.012,0.002) and lumbar ultimate strength(P=0.032, 0.008).Weight ratio of gatrocnemius and body increased significantly in VP2,VP3, VP4(P=0.024,0.014,0.000).There were significant improvements of fibra typeⅠproportion in VP3 and VP4(P=0.022,0.002),of fibra typeⅠCSA in all vibration groups (P=0.025,0.002,0.000,0000),and of fibraⅡb CSA in VP2,VP3,VP4(P=0.030,0.004, 0.000).The prolonged swimming times(P=0.042,0.000,0.007) and increased value of OD were found in VP2,VP3 and VP4.4.2 Osteoporosis treatment experimentVibrationⅢandⅣcontinued to be used in YT1 and YT2,and OT received vibra-tionⅣ.Osteoporotic modeling occurred in lumbar of young groups,and in both lumbar and femur of old groups 3 months after OVX.Compared with YC,the two vibration groups obtained increased BMD at lumbar (P=0.022,0.001).But only YT2 increased femur BMD(P=0.007) and improved bone microarchitecture and enhanced bone ultimate strength of lumbar and femur(P=0.020, 0.023) significantly.Two vibration groups were found that fibra typeⅠproportion (P=0.015,0.000),Ⅱa CSA(P=0.030,0.001),OD(P=0.014,0.003) and IOD(P=0.003, 0.001) increased significantly.But only YT2 increased significantly the weight ratio of gastroc-nemius and body(P=0.021),enlarged fibra typeⅠCSA(P=0.003),prolonged the swim-ming time(P=0.025) and decreased significantly proportion of fibra typeⅡa(P=0.013) andⅡb(P=0.048).Some parameters also increased significantly,such as weight(P=0.039),BMD of lumbar and femur(P=0.000,0.004),ultimate strength of lumbar and femur(P=0.038,0.014),weight ratio of gastrocnemius and body(P=0.036), swimming time(P=0.000) and OD value(P=0.012) of myoceptor in OT group.And OT also was found some significant improvements on bone microarchitecture,proportion (P=0.001,0.012) and CSA(P=0.047,0.033) of fibra typeⅠandⅡa. There were some close correlations between the muscle and bone quality.BMD of lumbar and femur correlated with ratio of gastrocnemius fibra significantly,and lumbar BMD also correlated with CSA of libra typeⅡa in the prevention experiment. In the treatment experiment,more tight correlations had be found between bone quailty including lumbar BMD,lumbar and femur ultimate strength,and muscle quality, such as ratio of gastrocnemius weight,CSA of fibra typeⅡb,OD value of myoceptor. The significant correlation between femur ultimate strength and propor-tion of fibra types also was found in the latter experiment.5 ConclusionsSpecial compound vibration with lower level could improve bone quality by enhanced BMD and bone strength,and improved bone microarchitecture of ovariectomized rats at different stages.And it could enhance muscle function by inhibited or improved amyotrophy,maintained or enhanced muscle force and improved some peripheral nerve function,which potentially resulted in an improvement of balance control.If these effects could be confirmed in clinics,the compound vibration machine would be helpful to increase the anti-fracture capability of bone and decrease the possibility of non-trauma falls.Based on that,a prospect in osteoporosis preven- tion and treatment of compound vibration machine would be on the way to reality.So it was worth to research more in future.