Objective To observe the clinical effect of GSS pedicle screw system and interbody autogenous iliac bone graft fusion in the treatment of lumbar spondylolisthesis.Methods Twenty-one lumbar spondylolisthesis patients was treated by GSS pedicle screw system and interbody autogenous iliac bone graft fusion.Followed up and analyzed the clinical therapeutic efficacy,rate of detachment and reduction,interbody fusion and intervertebral height change.Results Postoperative rate of detachment and reduction had significant difference compared with preoperative [(6.41 ± 6.90)％ vs.(36.75 ± 7.11)％,(86.75 ± 24.40)％ vs.0](q =19.60,19.72,P＜ 0.01).Final follow-up rate of detachment and reduction had no significant difference compared with postoperative (q =0.70,0.96,P ＞ 0.05).Postoperative intervertebral height had significant difference compared with preoperative[L4-5:(7.6 ± 1.3) mm vs.(5.2 ± 0.8) mm; L5S1:(8.4 ± 2.2) mm vs.(6.5 ± 1.5) mm] (q =6.64,3.83,P ＜ 0.01).Final follow-up intervertebral height had no significant difference compared with postoperative (q =2.48,2.42,P ＞ 0.05).All patients were bony fusion,rate of fusion was 100.00％(21/21).In accordance with the Japan institute of orthopaedics (JOA) low back pain surgery standards,the scores of 6 months,1 year,2 years significant increased compared with preoperative [(20.50 ± 3.83),(23.58 ± 3.60),(24.91 ± 2.90) scores vs.(9.67 ± 4.45) scores] (F =71.92,q =13.28,17.06,18.69,P ＜ 0.01).No complication of internal fixation for fracture or looseness.Conclusions The clinical effect of GSS pedicle screw system and interbody autogenous iliac bone graft fusion in the treatment of lumbar spondylolisthesis is good.It has advantages of bone graft area and bone mass,rate of fusion.It is one of better methods in the treatment of lumbar spondylolisthesis.

Objective To analyze the clinical effect of pedicle screw fixation in the treatment of multi-segmental lumbar fracture and dislocation under the guidance of visualization technique. Methods A total of 21 patients with multi-segmental lumbar fracture and dislocation were selected from November 2012 to November 2013. Before the screw implantation, the structure of bilateral pedicle was observed through Mimics software and the implantation parameters were measured. The position of pedicle screws by postoperative CT scan, operation time, and the satisfaction of the patients were assessed. The percentages of anterior vertebral height and Cobb′s angle were measured before operation, 2 weeks and 8 months after operation. Results All patients were satisfied with informed consent score and the way of pedicle screw and the selection of plant were more reasonable. With better screw position, shorter operative time and less blood loss and adverse reactions, pedicle screw fixation achieved good effect. Conclusion With high security and considerable clinical value, pedicle screw fixation in the treatment of multi-segmental lumbar fracture and dislocation under the guidance of visualization technique has exact and good effecct.