Comparison of the fenestrated pedicle screw and conventional pedicle screw in minimally percutaneous fixation for the treatment of spondylolisthesis with osteoporotic spine.

ABSTRACT

OBJECTIVES: To assess the feasibility of cement-augmented fenestrated pedicle screw for patients with spondylolisthesis with osteoporotic spine. PATIENTS AND METHODS: From January 2014 to March 2018, a retrospective study of 88 patients with spondylolisthesis and osteoporosis treated with minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) using the conventional pedicle screw (CPS group, n = 52) and the fenestrated pedicle screw (FPS group, n = 36) was performed with a follow-up of 30 months (range, 10-58 months). Clinical outcomes, overall changes in slip degree, and interbody fusion rates were evaluated via questionnaires and radiographic parameters. RESULTS: The VAS, ODI and JOA scores at 3 months were significantly improved in both groups compared with the preoperative assessment (p < 0.001). No significant differences in scores were found between the two groups at any time. Imaging results at different time points revealed greater postoperative improvement in the Taillard index in the FPS group compared with the CPS group. No significant differences in the interbody fusion speed or rates were found between the two groups. In the FPS group, cement leakage occurred in 22 of 97 screws (22.7%), and symptomatic cement leakage was not found. CONCLUSION: MIS-TLIF combined with fenestrated pedicle screws provided greater reduction than did MIS-TLIF combined with conventional pedicle screws in terms of postoperative slip degree. And the application of fenestrated pedicle screw did not obstruct the interbody fusion. Overall, MIS-TLIF combined with the fenestrated pedicle screws is an effective and safe technique for the treatment of spondylolisthesis with osteoporotic spine.