Effect of different cement distribution types on the efficacy of PVA in the treatment of OVCF and finite element analysis

Introduction: With global population aging, osteoporosis and its related complications are increasing markedly. Osteoporotic vertebral compression fracture (OVCF) represents one of the most prevalent and debilitating consequences of osteoporosis. Percutaneous vertebral augmentation (PVA), including percutaneous vertebroplasty and kyphoplasty, has become a widely accepted minimally invasive treatment owing to its rapid pain relief, minimal surgical trauma, and early functional recovery. Nevertheless, postoperative outcomes vary among patients, particularly regarding long-term pain control and spinal stability. This study aimed to investigate the influence of different intravertebral bone cement distribution patterns on the clinical and biomechanical efficacy of PVA, in order to identify the most optimal cement distribution mode. Methods: A retrospective analysis was conducted on patients with OVCF who underwent PVA between June 2021 and December 2022. Postoperative cement distribution was classified into six types (Types I–VI) based on lateral and vertical characteristics. Clinical outcomes, including visual analog scale (VAS), Oswestry Disability Index (ODI), Cobb angle, and anterior vertebral height ratio, were evaluated preoperatively, at 3 days postoperatively, and at 1 year postoperatively. Cement distribution types with superior clinical outcomes were further analyzed using finite element modeling. CT data from a healthy volunteer (T12–L2) were reconstructed to establish a three-dimensional spinal model. Finite element simulations were performed under six motion conditions to assess spinal stability and stress distribution. Results: All cement distribution types demonstrated significant postoperative improvement in VAS and ODI scores. However, at 1-year follow-up, Types I–III showed significantly better pain relief, functional recovery, and vertebral height maintenance compared with Types IV–VI. Finite element analysis revealed that cement contacting both superior and inferior endplates with bilateral continuity produced the most favorable biomechanical performance, characterized by lower stress concentrations on adjacent discs, vertebrae, endplates, and facet joints. Cement contacting a single endplate exhibited markedly increased stress, particularly during lateral bending and rotational movements. Conclusion: PVA is an effective treatment for OVCF. Cement distribution patterns that achieve bilateral continuity and full contact with both endplates provide superior long-term clinical outcomes and biomechanical stability, and are therefore recommended to reduce recompression risk and enhance spinal stability.