Aim:

To investigate the effect of distal fusion level on radiographic parameters and functional outcome in patients with degenerative spine disease who undergo long posterior fusion with instrumentation.

Material and methods:

This study included 78 adult patients aged 60 years who underwent long posterior fusion ( 6 levels) for spinal deformity with a minimum 2-year follow-up. The patients were divided into two groups based on distal fusion level (L5 group and iliac group). Spinopelvic parameters, including lumbar lordosis (LL) and sagittal vertical axis (SVA), were evaluated. Functional outcome was evaluated with the pain visual analog scale (VAS) and the Oswestry Disability Index (ODI) questionnaire. Correlations between clinical and radiographic parameters were calculated statistically.

Results:

In the L5 group, the mean SVA and LL significantly improved after surgery (p = 0.025 and 0.008, respectively ). Similarly, the SVA and LL also improved significantly in the iliac group (p = 0.002 and 0.001, respectively). In both groups, lumbar VAS, leg VAS and ODI scores significantly improved (p 0.001). The change in ODI score was significantly greater in the iliac group than the L5 group (p = 0.013).

Conclusion:

Although patients did not achieve the desired optimal spinal sagittal balance, both L5 and iliac groups showed significant improvement in VAS and ODI scores. The iliac group showed slightly better improvement in ODI score.