The impact of spino-pelvic parameters on pathogenesis of lumbar disc herniation.

PURPOSE: Controversies exist on the relative contribution of sagittal spino-pelvic alignment on pathogenesis of lumbar disc herniation. METHODS: Spinopelvic alignment parameters, pelvic incidence, pelvic tilt, sacral slope, pelvic radius-S1 end-plate ratio and pelvic radius-S1 angle, in 52 patients with lumbar disc herniation were compared with the same measurements in 43 healthy adult volunteers. RESULTS: Statistical analysis revealed significant difference in pelvic incidence and sacral slope between patients with lumbar disc herniation and normal population. CONCLUSION: Patients with lumbar disc herniation have a more vertical sacrum compared to the normal population which may result in higher intradiscal pressure in these patients.