A Novel Leverage Technique Using Monoaxial Pedicle Screw for Reduction of Thoracolumbar Compression Fractures: Surgical Technique and Analysis of Radiological Parameters

ObjectiveThoracolumbar compression fractures resulting from high-energy injuries are a common type of spinal fracture. Satisfying reduction of compressive vertebra body is essential for the clinical outcome. However, traditional distraction technique may lead to complications including pedicle screw loosening, pedicle screw breakage, and postoperative back pain because of excessive distraction. In this study, we reported a novel technique for reduction. Additionally, the effect and postoperative radiological parameters of this technique were compared with those of traditional distraction technique.MethodsThe clinical data of 80 patients who had been treated with posterior pedicle screw fixation from January 2019 to December 2020 was retrospectively analyzed. Thirty-six patients were performed with the leverage technique, while 22 patients were treated with the traditional distraction technique. When pedicle screw fixation was performed with either the leverage technique or the traditional distraction technique, fracture reduction was completed with monoaxial pedicle screws using either the leverage maneuver or distraction of adjacent vertebrae. Clinical evaluation, including operation time, hospital stay, blood loss volume, and postoperative complications were collected. The American Spinal Injury Association (ASIA) score for neurological condition and the visual analog scale (VAS) score for pain were used to evaluate the patients' functional outcome. The radiographic analysis included local kyphotic angle (LKA), regional kyphotic angle (RKA), anterior vertebral height (AVH), posterior vertebral height (PVH), and sagittal compression (SC). The student t-test and the chi 2-test (or the Fisher exact test) were used to compare the outcome measures between the two groups.ResultsThe leverage group comprised 36 patients, while 44 patients were included in the distraction group. No statistically significant differences were found in the demographic data. The VAS score in the leverage group (3.0 +/- 0.8) was significantly lower than that in the distraction group (4.2 +/- 0.6) on postoperative day 1. Total correction of the LKA in the leverage group (11.5 +/- 2.5 degrees) was significantly higher than that in the distraction group (7.1 +/- 1.3 degrees) (p = 0.0004). Total correction of the RKA was higher in the leverage group (12.1 +/- 4.3 degrees) than in the distraction group (6.1 +/- 0.9 degrees) (p = 0.005). The ratio of rear pillar /front pillar correction was 0.35 +/- 0.13 and 0.89 +/- 0.18 in the leverage and distraction groups, respectively (p = 0.014). Total correction of the upper and lower foraminal height in the leverage group was significantly less than that in the distraction group. The leverage group had significantly higher correction of the upper and lower intervertebral space height than the distraction group.ConclusionsOur novel leverage technique provided better kyphotic reduction and restoration than compared to conventional distraction technique in the surgical treatment of thoracolumbar compression fractures. Schematic diagram (A, C) and photos (B, D) captured during the surgery to illustrate the process of leverage via tightening the nuts of monoaxial screws with the rod holder as the fulcrum, which enables reduction of the fractured vertebra. Our novel leverage technique provided better kyphotic reduction and restoration compared to conventional distraction technique in the surgical treatment of thoracolumbar compression fractures. image