Factors predicting long-term outcome after short-segment posterior fixation for traumatic thoracolumbar fractures

Outcome of Long-Segment Fixation versus Inclusion of the Fractured Level in Short-Segment Fixation for Thoracolumbar Junction Fractures

Objective  The aim of this study was to compare the radiological outcomes of long-segment fixation and short-segment fixation, including the fracture level in patients treated for thoracolumbar junction fractures.

Methods  Data collected from records of patients with thoracolumbar junction fractures who were operated at our department. Neurological evaluation was done using American Spinal Injury Association classification score. Radiological parameters used were the Cobb's angle, vertebral body compression ratio, the anteroposterior spinal canal diameter, and the anterior and the posterior vertebral body heights. Patients were divided into two groups: group A included patients who underwent long-segment fixation and group B included patients who underwent short-segment fixation with inclusion of the fracture level.

Results  The mean preoperative Cobb angle was 22.51 degrees in group A and 19.37 degrees in group B. Both groups showed improvement in the postoperative Cobb angle as the mean in group A was 14.17 degrees and in group B was 11.77 degrees. The mean preoperative compression ratio in group A was 82.8%, while in group B it was 76%. The postoperative mean in group A was 89.2%, while in group B, it was 84%. The mean preoperative anterior vertebral body height of the fractured vertebra in group A was 16.7 mm, while in group B, it was 15.18 mm. The mean preoperative posterior vertebral body height in group A was 16.33 mm and that of group B was 19.41 mm. The mean postoperative anterior vertebral body height in group A was 17.66 mm and that of group B was 17.10 mm. The mean postoperative posterior vertebral body height in group A was 17.11 mm and that of group B was 20.79 mm.

Conclusion  Posterior short-segment fixation with additional screws at the fracture level provides similar—if not better—clinical and radiological outcomes to long-segment fixation in the treatment of thoracolumbar junction fractures.

Outcomes of Thoracolumbar Fracture-Dislocation Managed by Short-Segment and Long-Segment Posterior Fixation: A Single-Center Retrospective Study

BACKGROUND

Long-segment posterior fixation has been used as a mainstay treatment of spine fracture-dislocations. Studies using short-segment posterior fixation in cases of thoracolumbar fracture-dislocation are limited. We describe our experience of 26 patients with thoracolumbar fracture-dislocation treated by short-segment or long-segment posterior spinal fixation and fusion.

METHODS

This is a single-center retrospective study of 26 patients with thoracolumbar fracture-dislocation treated by long-segment (group 1, n = 12) and short-segment posterior instrumentation (group 2, n = 14). Clinical (visual analog scale [VAS], Oswestry Disability Index [ODI]), neurological (American Spinal Injury Association [ASIA] scale), radiological (kyphotic angle, translational percentage, and displacement angle), and surgical (blood loss, operative time) outcomes and complications were recorded with each method. The mean follow-up period was 8.64 months (6-20 months).

RESULTS

The mean duration of surgery was 3.92 ± 0.67 hours in group 1 and 3.21 ± 0.54 hours in group 2, and mean blood loss was 583.33 ± 111.5 mL and 478.6 ±112.2 mL in groups 1 and 2, respectively (P < .05). There was no radiologically visible pseudarthrosis, implant failure, or screw breakage in either group at follow up with no statistically significant difference between the 2 groups with regard to the radiological outcome (P > .05). Two patients in group 1 and 6 patients in group 2 improved after surgery at least 1 ASIA grade. VAS and ODI improved in both groups at the final follow up.

CONCLUSIONS

Short-segment fixation can be used for treating fracture-dislocation patients, as it results in less blood loss, decreased intraoperative time, and saves fusion segments with similar radiological and clinical outcomes as long-segment fixation.

LEVEL OF EVIDENCE

3.

The Predictive Value of the Load Sharing Classification Concerning Sagittal Collapse and Posterior Instrumentation Failure: A Systematic Literature Review

STUDY DESIGN

Systematic review.

OBJECTIVE

In 1994, the Load Sharing Classification (LSC) was introduced to aid the choice of surgical treatment of thoracolumbar spine fractures. Since that time this classification system has been commonly used in the field of spine surgery. However, current literature varies regarding its use and predictive value in relation to implant failure and sagittal collapse. The objective of this study is to assess the predictive value of the LSC concerning the need for anterior stabilization to prevent sagittal collapse and posterior instrumentation failure.

METHODS

An electronic search of PubMed, Medline, Embase, and the Cochrane Library was performed. Inclusion criteria were (1) cohort or clinical trial (2) including patients with thoracolumbar burst fractures (3) whose severity of the fractured vertebrae was assessed by the LSC.

RESULTS

Five thousand eighty-two articles have been identified, of which 21 articles were included for this review. Twelve studies reported no correlation between the LSC and sagittal collapse or instrumentation failure in patients treated with short-segment posterior instrumentation (SSPI). Seven articles found no significant relation; 5 articles found no instrumentation failure at all. The remaining 9 articles experienced failure in patients with a high LSC or recommended a different surgical technique.

CONCLUSIONS

Although the LSC was originally developed to predict the need for anterior stabilization in addition to SSPI, many studies show that SSPI only can be sufficient in treating thoracolumbar fractures regardless of the LSC. The LSC might have lost its value in predicting sagittal collapse and posterior instrumentation failure.

Comparing the Biomechanical Stability of Cortical Screw Trajectory Versus Standard Pedicle Screw Trajectory for Short- and Long-Segment Posterior Fixation in 3-Column Thoracic Spinal Injury

Background

Information on the performance of posterior fixation with cortical screw (CS) versus pedicle screw (PS) trajectories for stabilizing thoracolumbar burst fractures is limited. Therefore, we sought to analyze stability with CS versus PS in short- and long-segment fixations using a 3-column spinal injury model.

Methods

Nondestructive flexibility tests: (1) intact, (2) intact + short fixation, (3) intact + long fixation, (4) after burst fracture, (5) short fixation + burst fracture, and (6) long fixation + burst fracture using thoracic spine segments (7 CS, 7 PS).

Results

With CS, the range of motion (ROM) was significantly greater with short-segment than with long-segment fixation in all directions, with and without burst fracture (P ≤ .008). With PS and burst fracture, ROM was significantly greater with short fixation during lateral bending and axial rotation (P < .006), but not during flexion-extension (P = .10). Groups with CS versus PS were not significantly different after burst fracture during flexion-extension and axial rotation, with short (P ≥ .58) or long fixation (P ≥ .17). During lateral bending, ROM was significantly greater with CS versus PS, without burst fracture (long fixation, P = .02) and with burst fracture (short and long fixation, P ≤ .001).

Conclusions

CS trajectory is a valid alternative to PS trajectory for thoracic spine fixation in 3-column spinal injuries, and long-segment fixation is superior to short-segment fixation with either.