Clinical comparative study of two fixation methods for thoracolumbar spine fracture / 中华创伤杂志

ABSTRACT

ObjectiveTo compare the clinical results of pedicle screw fixation via the injured vertebra versus across the injured vertebra for thoracolumbar spine fracture.MethodsThe study reviewed 56 patients (41 males and 15 females,at age range of 21-66 years,mean 41.5 years) with thoracolumbar spine fractures managed with the two fixation methods from June 2005 to December 2008.The fracture segment included T12 in 13 patients,L1 in 27 and L2 in 16.According to the AO classification,there were six patients with type A1.2,29 with type A3.1,nine with type A3.2 and 12 with type A3.3.McCormack load score was 5-8 points (average 6.3 points). The spinal cord injury was classified as grade A in three patients,grade B in four,grade C in eight,grade D in 17 and grade E in 24 according to Frankel scale.The patients were divided into two groups,ie,across vertebral fixation group (27 patients) and via the vertebral fixation group (29 patients).All patients were selectively treated with monosegment bone graft simultaneously.The Cobb' s angle,restoration of the anterior height of the injured vertebra,improvement of spinal canal stenosis rate and Denis scale in local pain and work status were compared between the two groups.The bone graft fusion and spinal cord recovery of both groups were observed during follow-up.ResultsAll patients were followed up for 12-48 months (average 25.8 months).Implantation loosening occurred in one patient 1.5 month after operation in across vertebral fixation group.There were no significant differences in aspects of correction of Cobb' s angle,restoration of the anteriorheight of injured vertebra and improvement of spinal canal stenosis rate postoperatively as well as in aspects of restoration of anterior height of injured vertebra and improvement of spinal canal stenosis rate at the latest follow-up between the two groups ( P ＞ 0.05).The postoperative loss of correction rate of Cobb's angle of both groups existed,with significant difference (P ＜0.05). The differences of the Cobb's angle at the latest follow-up and after operation were significant in the across vertebral fixation group ( P ＜ 0.05) but insignificant in the via vertebral fixation group (P ＞ 0.05 ).Bone graft fusion occurred in 21 patients (78％) in the across vertebral fixation group and in 27 patients (93％) in the via vertebral fixation group ( P ＜ 0.05 ).Denis scale indicated a better recovery in the local pain of via vertebral fixation group compared with the across vertebral fixation group ( P ＜ 0.05 ),but showed no significant differenc e in work status between the two groups ( P ＞ 0.05 ).ConclusionsCompared with across vertebral fixation,the pedicle screw fixation via the vertebra has the advantages of higher fusion rate and better correction rate of Cobb' s angle and is a better choice for thoracolumbar spine fracture with posterior approach.