Abstract:

BACKGROUND: Kyphoplasty has obtained favorable clinical effects, but adjacent vertebral fracture has been reported. Therefore, it is important to analyze the possible reasons for adjacent vertebral fracture based on biomechanics.
OBJECTIVE: To explore the biomechanical effectsof percutaneous kyphoplasty (PKP) on adjacent vertebrae and analyze causes for adjacent vertebral fracture.
METHODS: T ₁₀-L₂ segment data were obtained from CT scans of a female with single T₁₂ compressed fracture who underwent PKP. A three-dimensional finite element model of thoracolumbar Spine (T ₁₀-L₂) was built in the MIMICS and the ABAQUS software. The stress on the annulus fiber, nucleus pulposus, endplate and facet joints under axial pressure (0.3, 1.0, and 4.0 MPa) were analyzed to evaluate the influence of PKP on the vertebrae adjacent to fractures.
RESULTS AND CONCLUSION: The 3D finite element models before and after PKP were successfully established. The stresses were increased with increasing axial pressure. In the model after PKP, the stress augmentation scope on adjacent end plates (T ₁₁ low plate and L1 top plate) and intervertebral disc (T₁₁-₁₂ and T₁₂-L₁) increased. The maximum Von Mises stress on adjacent vertebrae (T₁₁ and L₁) increased, but the maximum Von Mises stress on end vertebrae (T₁₀ and L₂) decreased. Postoperative adjacent vertebral fracture after PKP may be related to the changes of biomechanical effects on adjacent vertebrae.