Comparison Of Unilateral Or Bilateral Pedicle Screw Fixation At The Level Of Fracture Versus Posterior Short-Segment Fixation Alone In The Treatment Of Thoracolumbar Junction Fractures

Objtctive: The posterior short-segment pedicle screw fixation is widely used in the treatment of thoracolumbar junction fractures,while the traditional short-segment pedicle screw fixation alone has been reported to have a high failure rate of fixation and more complications.It is still controversial that some scholars have put forward the technique of pedicle screw fixation including the fractured vertebra in order to make up for this deficiency.The purpose of this study was to compare the clinical efficacy of three different pedicle screw fixation methods for treating thoracolumbar junction fractures including unilateral or bilateral pedicle screw fixation at the level of fracture and posterior short-segment fixation alone,and to explore the mechanism,advantages,indications and appropriate number of pedicle screw,so as to provide a reference for clinical treatment.Methods: In this retrospective analysis,98 cases underwent posterior short-segment pedicle screw fixation treatment of thoracolumbar single vertebra fracture in our hospital from January to December 2017.According to the different fixation methods,the patient were divided into three groups:Group A included 32 patients treated by traditional short-segment pedicle screw fixation alone,Group B included 28 patients treated by unilateral pedicle screw fixation at the level of fracture,and Group C included 38 patients treated by bilateral fracture-level pedicle screws.All patients were recorded gender,age,fracture location,operative time and intraoperative blood loss, collected imaging data of preoperative,after surgery 3 days and at last follow-up,measured and recorded the anterior height ratio of injured vertebra,sagittal kyphosis deformity Cobb Angle of injured vertebra,visual analogue score(VAS),Oswestry disability index(ODI).All patients were followed up to find out whether there were complications such as internal fixation looseness and fracture.The data obtained from the three groups were collated and statistically analyzed.Results: The patients among three the groups showed similar outcomes with regards to gender composition( ? 2=0.636,P= 0.728),age(F=0.487,P=0.616),fracture location distribution( ? 2=0.355,P= 0.999),fracture type( ? 2=0.334,P= 0.846),preoperative VAS score(F=0.851,P=0.430),preoperative anterior height ratio of injured vertebra(F=0.813,P=0.447)and preoperative sagittal Cobb Angle(F=0.433,P=0.650).There were no statistically significant differences in operative time(F=0.405,P=0.668),intraoperative blood loss(F=0.825,P=0.441),VAS score(F=0.383,P=0.683),anterior height ratio of injured vertebra(F=0.545,P=0.581),and sagittal Cobb Angle(F=2.060,P=0.133)among the three groups on third day after surgery.98 cases were followed up for 12-20 months,the average followed up time was 16.2 months.There were no serious complications occuring during our study,such as incision infection,internal fixation loosening or fracture.At the last follow-up,We did not find any statistically difference among the three groups in follow-up time(F=0.720,P=0.489),VAS score(F=2.350,P=0.101)and ODI score(F=0.721,P=0.489).The group B(unilateral pedicle screw fixation at the level of fracture)and group C(bilateral pedicle screw fixation at the level of fracture)had better significant difference than group A(traditional short-segment pedicle screw fixation alone)in the ratio of anterior height of injured vertebra(F=12.079,P=0.000),sagittal Cobb Angle(F=7.046,P=0.001),the loss of ratio of anterior height of injured vertebra(F=15.175,P=0.000)and the loss of the sagittal Cobb Angle(F=4.349,P=0.016).while not find any statistically difference between group B(unilateral pedicle screw fixation at the level of fracture)and group C(bilateral pedicle screw fixation at the level of fracture)(P>0.05).Conclusion: The three kinds of posterior short-segment pedicle screw fixation methods can effectively treat thoracolumbar fractures and the early postoperative effect is similar.Although three surgery methods are inevitably exist in the loss of injured vertebral height and kyphosis deformity Angle,but unilateral or bilateral pedicle fixation at the level of fracture can more effective decrease the loss of injured vertebrae height in the long time and reduce incidence tardive kyphosis deformity Compared to the traditional cross of injured vertebra posterior short-segment pedicle screw fixation,and put more screw at the level of fracture did not significantly increase the operative time and intraoperative blood loss.There was no significant difference in the curative effect between unilateral pedicle screw fixation at the level of fracture and bilateral pedicle screw fixation at the level of fracture,it objectively reduces the hospitalization cost of patients and is worthy of clinical promotion and application duing to unilateral pedicle screw fixation at the level of fracture could reduce the use of pedicle screw number.