Complications of 2-level dynamic stabilization.

AIM: A retrospective chart and a radiographic review. Evaluation of postoperative complications, clinical improvements and radiological parameters in patients who underwent surgery using a dynamic system for 2-level lumbar stabilization. We aimed to investigate the postoperative complications, such as screw loosening, screw breakage and ASD, in patients who underwent surgery with 2-level dynamic stabilization systems.

MATERIALS AND METHODS: Dynamic lumbar systems enable the stabilization of unstable degenerative spines, while preventing fusion-related complications, such as adjacent segment disease(ASD) and pseudarthrosis. In our study a total of 103 patients with lumbar degenerative spinal instability underwent 2-level dynamic stabilization. Clinical findings were reviewed at a 2-year follow-up. Screw breakage and loosening were evaluated during this duration together with clinical findings.

RESULTS: Visual analog scale(VAS) and Oswestry Disability Index(ODI) scores significantly decreased at the four-month evaluation, and they were also decreased at the 1-year follow up and at the 24th postoperative month. Adjacent segment disease was diagnosed in twelve (8 females, 4 males) of the 103 patients in the follow-up radiological and clinical controls. There were 9 screw breakages and 4 screw loosening. The complication rate of 2-level of dynamic stabilization was high in this study.

CONCLUSIONS: Our results showed that complications (screw loosening or breakage and adjacent segment disease) are not rare after using the 2-level dynamic stabilization system, unlike the acceptable results with the single-level dynamic system. The most probable explanation is that the instrument system behaves more rigidly with every additional segment.