Guide chunnel assistance vs conventional method in placement of percutaneous pedicle screw

English Keywords:Percutaneous pedicle screws  The guide chunnel  Localization  Fluoroscopy  Radiation

English Abstract:

  【Abstract】 Objectives: To compare the time and accuracy of screw placement, time of radiation exposure between guide chunnel assistance and the conventional method in placement of percutaneous pedicle screw. Methods: There were 70 thoracolumbar patients with vertebral fracture who were randomly divided into 2 groups: in group A, there was 35 patients who underwent 180 percutaneous pedicle screws placement by conventional method; in group B, there were 35 patients who underwent 178 percutaneous pedicle screws placement by guide chunnel assistance. All the 70 cases were performed by the same surgeon. The time and accuracy of pedicle screw placement, time of radiation exposure between the two groups were recorded and compared. The accuracy of pedicle screw placement was evaluated and graded according to twice consecutive postoperative CT examination. Results: There were no significant statistical differences in age, body mass index(BMI), complicating diseases, type of fracture and sex ratio between the two groups(P>0.05). The mean time of a single pedicle screw placement in group A(14.11±3.32 minutes) and that in group B(11.35±2.82 minutes) was significantly different(P=0.0042). The time of average radiation exposure was 8.06±2.15s in group B and 12.07± 3.06s in group A（P=0.0031). In group A, a total of 155 screws(86.11%) were evaluated in grade A, 23 screws(12.78%) in grade B, 1 screw(0.56%) in grade C, 1 screw(0.56%) in grade D. In group B, 156 screws(87.64%) were evaluated in grade A, 20 screws(11.24%) in grade B, 1 screw(0.56%) in grade C, 1 screw(0.56%) in grade D. There were no statistical differences in all grades between the two groups(P>0.05). Conclusions: The percutaneous pedicle screw placement with guide chunnel assistance can provide the same accuracy of screw placement as the conventional method, and it can significantly reduce the time of pedicle screw placement and time of radiation exposure.