| ObjectivesTo research the effect of polyaxial and monoaxial pedicle screw on the intervertebral space angle of lumbar fusion patients. Methods150cases of monosegment fusion patients are selected from department of orthopaedics2nd affiliated hospital of Zhejiang University between2009to2011,83males and67females,age23-79,mean age52.22years old.They are distributed to3groups.Group A uses4polyaxial pedicle screws,Group B uses2polyaxial pedicle screws,and Group C uses2monoaxial pedicle screws.Radiographs of lateral lumbar are achieved, and intervertebral space angle of the fusion segment are measured by PACS image analysis system.ResultsThe preoperation intervertebral space angles of the three group have no significant difference(P>0.05).The intervertebral space angles between pre and post operation have no significant difference(P>0.05).The ratio of increased cases and decreased cases of the three groups have no significant difference(P>0.05).The postoperation angles of the three groups have no significant difference(P>0.05).The mean change of intervertebral space angle of Group A is2.20±1.76°,mean rate of change is0.28±0.21.While the mean change of intervertebral space angle of Group B is2.23±1.83°,mean rate of change is0.32±0.27,And Group C3.85±3.02±°and0.58±0.45.The change of intervertebral space angle and rate of change of Group A and Group B are both significantly less than Group C(p<0.05),but Group A and Group B don’t have significant difference.The ratio of increased cases and decreased cases of the three groups have no significant difference.Conclusions1Both kinds of pedicle screws don’t change the pre and post operation intervertebral space angles.2Postoperation intervertebral space angles are not changed by using polyaxial or monoaxial pedicle screws.But the changing range of polyaxial pedicle screws is less than monopolyaxial pedicle screws,and combined use of polyaxial and monoaxial pedicle screws have the same effect as polyaxial pedicle screws. |
PDF Full Text Request