The Basic And Clinical Research On Oriented Bone Cement Injector

Part ? Research on oriented bone cement injector using 3D model of thoracolumbar vertebraeObjective:To make the thoracolumbar osteoporotic vertebral model by digital orthopaedics science and technology of computer.And observe the distribution and leakage of bone cement in each segment of vertebral.To provide a research model for osteoporotic thoracolumbar fracture and to preliminarily evaluate the effect of controllable directional bone cement injector on the bone cement distribution.Methods: 15 cases of patients(male 7,female 8,average age 68.4±8.9)with thoracolumbar OVCFs were selected.CT scans were made for the T7-L5 regions.The CT data of T7-L5 regions were reconstructed by Bow Surgical planning system software and mimics.The 3D printer produces the model.Unilateral PKP were performed on each T7-L5 vertebrae.Fifteen spinal models(165 vertebrae)were constructed using oriented bone cement injector or traditional bone cement injector.Observe the leakage and dispersion of bone cement in T7-L5 regions models.Results:In the controllable directional bone cement injector group has more ideal bone cement distribution.The proportion of centrally-distributed vertebral bodies was91.52%(151/165);The proportion of centrally-distributed bone cement vertebral in the traditional bone cement injector group was 65.45%(108/165)(P < 0.05).In t7-t12,there was no significant difference in the rate of centrally-distributed bone cement between 2 groups(P>0.05).In L1-L5,the difference was significant between the 2 groups(P<0.05).In the oriented bone cement group,14 vertebrals occur bone cement leakage and 16 vertebrals in the traditional bone cement group,and there was no significant difference between two groups.Conclusion : The model of thoracolumbar osteoporotic compression fracture could be made with the help of computer-aided 3D printing technology,which was highly repeatable and does not require strict ethical examination.The the oriented bone cement injector can effectively achieve the distribution of bone cement across the midline in the vertebral body through the unilateral pedicle puncture approach,and its influence on spinal mechanics will be further studied in the following parts.Limited to the printing material technology,the 3D model in this part cannot fully simulate the bone strength and stiffness,so it is not suitable to use the 3D printed model for subsequent biomechanical research.Part ? Biomechanical analysis of the application of oriented bone cement injector in unilateral PVPObjective:To discuss the feasibility and advantages of the application of the oriented bone cement injector from the perspective of biomechanics by simulating Unilateral and bilateral vertebroplasty in vitro.Methods:The osteoporosis model of SAWBONES company were made into OVCF experiment module with the size of 3 * 4 * 5cm,which was randomly divided into three groups with 12 experiment modules in each group.Control group,no manipulation;In the oriented bone cement injector unilateral group,the vertebral body bone cement was strengthened by unilateral puncture with the oriented bone cement injector.In the conventional bilateral group,the traditional bone cement injector was used for bilateral puncture vertebral bone cement reinforcement.Three groups of OVCF experimental modules were tested by mechanical testing machine,and the stiffness changes of the modules after strengthening were recorded.3D spiral CT was used to scan the three groups of osteoporostic compression fracture modules after bone cement strengthening,observing the distribution of bone cement,and measuring the height change of the modules after bone cement strengthening.Results:The stiffness of the OVCF module in the unilateral controllable group was 815.2±231.9n/mm,while that of the conventional bilateral group was921.8±145.1n/mm.The module stiffness of the two groups was significantly higher than the control group(P<0.05).There was no significant differences in the stiffness of OVCF module between the unilateral group and the conventional bilateral group(P>0.05).The pre-strengthening height of OVCF module in the unilateral group was24.84±0.11 mm,and the post-strengthening height was 25.77±0.35 mm.The pre-strengthening height of OVCF module in the conventional bilateral group was24.89±0.23 mm,and the post-strengthening height was 25.94±0.42 mm.The strengthening height of the two groups was larger than before.However,the effect was not obvious.Compared with the conventional bilateral group,there was no significant difference in OVCF module height after bone cement strengthening in the unilateral controlled group(P>0.05).All the bone cement in the OVCF module in the controllable direction group diffused across the center line of the module and became a whole bone cement mass across the center line of the module.The conventional bilateral bone cement consists of two separate bone cement aggregates in the OVCF module.Conclusion: The application of oriented bone cement can diffuse the bone cement to the non-puncture side,and the morphology distribution of the bone cement is satisfactory.The unilateral pedicle approach can obtain the mechanical effect of the bone cement distribution of the bilateral pedicle approach,effectively restore the vertebral stiffness,and better reconstruct the stability of the spine,which is simple,feasible,safe and effective.Part ? Clinical evaluation and imageology study on the treatment of osteoporotic thoracolumbar compression fracture with oriented bone cement injectorObjective:Unilateral PKP for thoracolumbar osteoporotic compression fractures was performed using oriented bone cement injector to observe the surgical efficacy,safety and distribution of bone cement of fractured vertebra.Methods:Clinical data of 280 patients with OVCF were concluding.All patients received unilateral PKP treatment.143 cases were treated with oriented bone cement injector(observation group,50 males and 93 females,aged 55-83 years),137 cases were treated with conventional bone cement injector(conventional group,46 males and 91 females,aged 55-84 years).The operation time,frequency of c-arm fluoroscopy,bone cement injection mass,visual analogue scale(VAS)of pain,Oswestry disability index(ODI)score,distribution and leakage of bone cement,Cobb Angle of the affected vertebra and the recovery of the leading edge height of the affected vertebra were observed.Results:There was no significant differences between the two groups in gender,age and bone cement distribution(P>0.05).The mean operation time was(45.3±12.5)min in the observation group and(46.6±11.2)min in the conventional group.The mean bone cement injection amount was(5.98±1.18)ml in the observation group and(4.891±2.06)ml in the conventional group.The average frequency of c-arm fluoroscopy was(42.1±11.8)in the observation group and(50.6±15.1)in the conventional group.There were no significant differences in operation time,bone cement injection mass and c-arm fluoroscopy times between conventional group and observation group(P>0.05).At the first day,the fifth day and the last follow-up time,the two groups were significantly different from those in VAS score and ODI score(P<0.05).There were significant differences between the observation group and the conventional group on the 1st day after the operation in VAS scores(P<0.05).At the 5th day and last follow-up time,the VAS scores of the observation group were same from the conventional group(P>0.05).And there was no differences in ODI scores between the two groups(P>0.05).The bone cement leakage in the observation group and the conventional group were 11.89% and 20.44%,respectively,with no statistically significant difference(P>0.05).At the last follow-up time,the height of anterior vertebral increased significantly in both observation group and the conventional group(P<0.05).There was no significant differences between the two groups in injured-vertebral height(P>0.05).The Cobb Angle in both observation group and conventional group,were significantly improved at 5 days after surgery and at the last follow-up time(P<0.05).There was no significant difference in the improvement of Cobb Angle between the two groups(P>0.05).Observation group and conventional group from T10 to L5,bone cement ?degree distribution rate are decreasing trend.Observation group T10-L5 all ?degree distribution proportion of vertebral body bone cement obviously higher than that of conventional group,difference was statistically significant(P < 0.05).In T10-T12,two groups of observation group and conventional group were mainly ?degree distribution,and compared two groups of bone cement ? degree distribution differences had no statistical significance(P>0.05);In L1 and L2 vertebral observation group mainly ?degree distribution,conventional group mainly ?degree of bone cement distribution;In the L3-L5 vertebral section,no obvious differences in group of four types of bone cement distribution,regular group mainly?-?bone cement distribution.? cement distribution rate of L1 to L5 in observation group was obviously higher than that in conventional group(P<0.05).Conclusion : The oriented bone cement injector can effectively achieve the bilateral distribution of bone cement of injured vertebra by unilateral pedicle approach,reducing the time of X-ray exposure of doctors and patients,and achieving satisfactory surgical effects,which is feasible and effective.