The Clinical Comparison Between Short-segment And Long Segment Posterior Fixation In Treatment Of Thoracolumbar Burst Fracture

Objectives: There’s still controversy on how to treat thoracolumbarfracture. Although most doctors think it’s necessary to treat the unstable burstfracture with surgical methods, they have different opinions on the choice ofspecific surgical approach. General opinion is the burst fracture should betreated with short-segment transpedicular fixation to get solid stability, and thespinal canal should be decompressed thoroughly. Short-segment posteriorfixation is the most common and simple treatment, with advantages of lessfusion of vertebral body. Review of literature shows in the long-termfollow-up founding, sole SSPF can lead to9%-54%implant failure andrecurrent kyphosis, among the patients with implant failure about50%complained the back pain. In order to prevent these complications, a variety oftechniques have been developed to augment the anterior column stability, suchas transpedicular bone grafting, PMMA injection, or anterior fixation andconstruct implantation, or increase the instrumented segment. Simply increasethe instrumented segments seems to be a reasonable choice, however, there’sno consensus on this issue. In this paper, the author investigates the clinicaloutcomes and complications of the short-segment posterior fixation andlong-segment posterior fixation.Methods: The author retrospectively investigates47patients with acuteunstable thoracolumbar burst fracture and without paraplegic sign. All patientsreceived surgical treatment, with average follow-up of17months. Thepatients were divided into2groups: group1consists of27patients who weretreated with long segment fixation (2levels above and2levels below theinjury vertebral body), group2consists20patients who were treated withshort-segment fixation (1level above and1level below the injury vertebral body). Compare the preoperative parameters, such as age, gender, injuryseverity, canal compromise and neurological function, there are no significantdifference between the2groups. Analyze the radiographic parameters beforeand after the operation. In the CT, measure the anterior vertebral bodycompression rate, local kyphotic Cobb angle. Local kyphotic angle iscalculated with the Cobb method.Results: The compression rate of the anterior vertebral body in the shortsegment group is42.7±10.0%, in the long segment group is43.5±9.8%,there is no significant difference; the Cobb’s angle in short segment group is20.8±3.3%, in long segment group is21.3±3.5%, there is no significantdifference. At the time of one week post-operation, there is significantdifference of the compression rate and Cobb angle compared withpre-operation in both groups, but there is no significant difference ofcorrection rate between2groups. At the time of follow-up, in the group ofshort segment, the compression rate, Cobble angle are6.7±5.5%，2.3±3.3°separately, there’s slight lose of correction.Conclusions: This research shows there’s no significant differencebetween the group of long segment and the group of short segment in thetreatment of specific thoracolumbar burst fracture. After careful evaluation ofthe fracture, one could choose short-segment transpedicular screw internalfixation as appropriate approach.