Levent AYDIN, Buse SARIGÜL, Arda TOPÇU, Faruk Buğra ÖZDEMİR, Ali Fatih RAMAZANOĞLU
Journal of Turkish Spinal Surgery - 2026;37(4):142-147
Objective: This study aims to investigate the correlation between sacral morphological parameters and degeneration of the L4-5 and L5-S1 discs, with particular emphasis on STA and SI. Materials and Methods: This retrospective cohort study includes patients who were admitted with back pain and/or radicular pain. Degeneration at L4-5 and L5-S1 was evaluated using Pfirrmann grading on lumbar magnetic resonance imaging. Pfirrmann grades 1-2 were considered non-degenerative, while Pfirrmann grades 3-5 were considered degenerative. Pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), lumbar lordosis (LL), LL distribution index (LLDI), sacral inclination (SI), and sacral table angle (STA) were measured from standing lumbosacral X-rays. Results: Ninety consecutive patients were included and the mean age was 47.42+/-9.84. Fifty-four patients were female and 36 were male. Disc degeneration was observed at L4-5 in 44 patients (48.9%) and at L5-S1 in 47 patients (52.2%). Degeneration at both disc levels was observed in 38 patients. PI, PT, and SS were significantly higher, whereas LLDI, SI, and STA were significantly lower in patients with two-level disc degeneration. There was no statistically significant difference in LL between the degenerative and non-degenerative groups. SI was negatively correlated with Pfirrmann grades in both L4-5 and L5-S1. STA showed a stronger negative correlation with Pfirrmann grades at both levels. The intensity of degeneration was inversely correlated with STA. The mean STA values were 105.09+/-3.09 derece in no degeneration, 100.01+/-4.00 derece in single-level degeneration and 95.85+/-4.17 derece in two-level degeneration groups. Conclusion: Sacral morphology shows significant association with lower lumbar disc degeneration. A lower STA value is associated with increased disc degeneration at the L4-L5 and L5-S1 levels. STA may be a morphological parameter reflecting the biomechanical environment of the lumbosacral junction.
