The biomechanical and clinical study of the percutaneous pedicle screw fixation in the treatment of thoracolumbar fractures / 中华骨科杂志

ABSTRACT

ObjectiveTo evaluate the biomechanical stability and the clinical efficacy of the percutaneous pedicle screw fixation in the treatment of thoracolumbar fractures. Methods Twelve lumbar fracture models were made on fresh calf lumbar spine specimens to compare the stability of the 4 monoaxial screws and 4 muhiaxial screws transpedicular fixation by examining the range of motion(ROM) in flexion,extension, lateral bending, and torsion. Sixty cases of thoracolumbar fractures without neuro-deficiency were treated surgically, 11 of the minimally invasive group(monoaxial screw group) and 18 of the open surgery group(multiaxial screw group) were followed up more than 12 months. ResultsThe 4 monoaxial screws transpedicular fixation specimen exhibited a smaller ROM significantly in flexion, extension compared withthe 4 multiaxial screws transpedicular fixation specimen. The 4 monoaxial screws transpedicular fixationspecimen exhibited a significantly smaller ROM in flexion and extension than the intact specimens. TheROM in the 4 multiaxial screws transpedicular fixation specimen and the intact showed on significant differences. There were no significant differences between the two groups in the preoperative and postoperative anterior fractured vertebral height (AVH) and the Cobb's angle (CA), but there were significant differences in the AVH and the CA between preoperative and postoperative in the two groups. There were significant differences in the correction loss of the AVH between the two groups at final follow-up.ConclusionThe percutaneous pedicle screw fixation using Sextant system is a good minimally invasive surgical choice for patients with thoracolumbar fractures without neuro-deficiency, but which has a loss of the AVH and worse flexion-extension stiffness in follow-up compared with the open monoaxial screws fixation.