USF-LVHN SELECT
Acute Disc Herniation at the Proximal Junctional Segment (UIV/UIV + 1) Following Long Segment Spinal Fusion With Cement-Augmented Instrumentation: A Retrospective Study.
Publication/Presentation Date
6-9-2026
Abstract
BACKGROUND: Prophylactic cement augmentation at the uppermost instrumented vertebra (UIV) and the adjacent supravertebra (UIV + 1) is commonly used during long-segment fusion for adult spinal deformity to reduce the risk of proximal junctional failure. While this strategy may protect against osteoporotic fracture, its impact on adjacent soft tissues-particularly the intervertebral disc-remains poorly characterized. Acute disc herniation (ADH) at the proximal junction represents a rare but potentially catastrophic complication.
METHODS: In this retrospective cohort study, 173 patients underwent long-segment posterior spinal fusion (≥5 levels) with prophylactic polymethylmethacrylate (PMMA) cement augmentation at UIV/UIV + 1 between January 2016 and January 2024. Nine patients developed ADH at the proximal junction. After 1:3 propensity score matching on age,
RESULTS: Baseline characteristics were well balanced between matched groups, with no significant differences observed for matched or unmatched variables (all
CONCLUSIONS: Despite preserved bone quality, ADH was associated with profound junctional collapse and rapid neurological decline, suggesting a biomechanical failure mechanism driven by PMMA-related overstiffening. Strategies that preserve a gradual stiffness transition at the proximal junction may be necessary to mitigate this risk.
CLINICAL RELEVANCE: Although rare, acute proximal junctional disc herniation can result in rapid neurological deterioration following long-segment fusion with prophylactic UIV/UIV+1 cement augmentation. Spine surgeons should maintain a high index of suspicion for this complication in patients presenting with new neurological symptoms and consider strategies that minimize abrupt stiffness transitions at the proximal junction.
ISSN
2211-4599
Published In/Presented At
Saleh, D., Alkadri, A. Z., Bagherzadeh, S., Vanderpool, J., Pradhan, A., Mejica, D., Daulat, S., Rubio, D. S., Hayman, E., Rostami, M., Kim, P., & Alikhani, P. (2026). Acute Disc Herniation at the Proximal Junctional Segment (UIV/UIV + 1) Following Long Segment Spinal Fusion With Cement-Augmented Instrumentation: A Retrospective Study. International journal of spine surgery, 8902. Advance online publication. https://doi.org/10.14444/8902
Disciplines
Medical Education | Medicine and Health Sciences
PubMedID
42264890
Department(s)
USF-LVHN SELECT Program, USF-LVHN SELECT Program Students
Document Type
Article