BACKGROUND:Monoaxial pedicle screws are not conducive to the instal ation during percutaneous pedicle screw technique, but it has better mechanical conductivity and stability than polyaxial pedicle screws. How to select and use these two kinds of screws in the clinic to exert their advantages and to further elevate efficacy has become a subject worthy of reflection. OBJECTIVE:To compare the clinical efficacy of percutaneous pedicle screw placement for thoracolumbar fracture using monoaxial and polyaxial pedicle screws at different placement selections. METHODS:A total of 46 cases of thoracolumbar fracture without neurological symptoms underwent minimal y invasive percutaneous pedicle screw fixation. 25 patients (monoaxial screw group) were treated with monoaxial pedicle screws and the other 21 ones (polyaxial screw group) with polyaxial pedicle screws. Kyphotic angle, correction rate, correction loss rate and height of injury vertebrae were compared before and after fixation in both groups. The therapeutic effects of monoaxial and polyaxial percutaneous pedicle screw fixation in the treatment of thoracolumbar fractures were evaluated. RESULTS AND CONCLUSION:(1) Fixation time, blood loss, complication and hospital stay were not significantly different in both groups (P>0.05). (2) Kyphotic angle and height of the fractured vertebra body were significantly different between the two groups (P0.05). (4) These findings indicate that compared with the polyaxial percutaneous pedicle screw fixation, the monoaxial pedicle screw may be preferable in percutaneous pedicle screw fixation for thoracolumbar fractures, has more satisfactory fracture distraction reduction, and has less postoperative correction loss rate.