Abstract:

BACKGROUND: Clinical treatments for spondylolisthesis including simple decompression, anterior lumbar interbody fusion (ALIF), posterior lumbar interbody fusion (PLIF) or the 360° combination of ALIF and PLIF, which has its own characteristics.
OBJECTIVE: To evaluate the effects of GSS II system combined with interbody graft in treating spondylolisthesis.
METHODS: Totally 38 spondylolisthesis cases were selected. Firstly, 2 pedicle screws were inserted into both sides of vertebral slips, then additional 2 pedicle screws were inserted into subordinate vertebral of vertebral slips. The position of screws was confirmed by C-arm imaging machine. After that, the spinous process and vertebral plates were cut off, the bone bed was prepared, and vertebral slip was replaced. The bone fragments and ilium were grafted into intervertebral space. Finally, regulated GSS system, placed drainage, and closed the incision. X-ray changes, signs and symptoms changes, material biocompatibility, as well as bone fusion status was observed at 8 weeks after operation and in the follow-up. 
RESULTS AND CONCLUSION: X-ray films showed that spondylolisthesis of 36 cases were improved, including 28 cases with completely reduction and 10 cases with I spondylolisthesis. The pedicle screw-rod fixation system showed good stability, no screw, rod loose or shedding could be seen at 8 weeks after operation. In the follow-up of 36 cases, no shedding status could be found, and the symptoms of spodylolisthesis were improved, and therapeutic effects evaluation revealed 33 cases were excellent, and 3 cases were good. All results demonstrated that GSS system is a good fixation system with sample operation and strong anti-pull-out strength, which can be used in treating spondylolisthesis.