Experimental Study On Animal Model Constructionof Vertebral Refracture After Vertebral Augmentation Surgery And Secondary Augmentation For Treatment

Objective:To investigate the effect of different surgical methods(PKP and PVP)on vertebral refracture by constructing an animal model of vertebral refracture after vertebral reinforcement.To investigate the effect of PVP on the treatment of refracture after PKP.Methods:60 thoracolumbar vertebral bodies from experimental pigs were selected,soaked with decalcification agent to the osteoporosis standard,and then compressed in MTS Acumen3 machine to reduce the height by 25%and get the stiffness by recording the data of force changes over time so as to make models of osteoporotic vertebral compression fracture.The vertebral body models were randomly divided into two groups(30 models in each group)for corresponding vertebral strengthening:PKP group(group A)and PVP group(group B).Postoperative biomechanical indexes(stiffness with specimens again compressed under MTS machine)and vertebral body height were measured to evaluate the effect of different surgical methods on refracture of postoperative vertebral body.During the experiment,one vertebral body in group A and two vertebral bodies in group B were damaged and could not continue the experiment.The vertebral bodies of group A that were compressed again after PKP surgery were set as group C,and PVP was performed on the vertebral bodies of group C.The biomechanical indexes(stiffness obtained after compression)and the recovery rate of vertebral height were measured to evaluate the therapeutic effect of secondary surgery for vertebral fracture after primary vertebral reinforcement.Result:The vertebral body models of osteoporotic compression fracture were made successfully.After the first strengthening,stiffness of vertebral bodies in group A and group B were higher than before(P<0.05).There was no significant difference in the stiffness and recovery rate of vertebral height between the two groups(P>0.05).After the second reinforcement,the vertebral stiffness of group C was higher than that of group A after the first reinforcement(P<0.05).After each operation,vertebral height was restored to a certain extent,but the recovery rate of vertebral height after secondary reinforcement was lower than that after primary reinforcement(P<0.05).Conclusion:There was no significant difference in the effect of different surgical methods(PKP and PVP)on vertebral refracture.PVP treatment for the refracture of the vertebral body after PKP surgery can continue to enhance the strength of the vertebral body,but the effect of restoring the height of the vertebral body is not as good as the initial reinforcement.