A Comparative Biomechanical Study of HA Block Kyphoplasty for Osteoporotic Vertebral Fractures

We innovated a new technique and hydroxyapatite material “HA Block” in order to decrease complications such as pulmonary embolization and correct kyphosis due to osteoporosis. A cadaveric study of vertebroplasty was attempted to confirm accurate the efficacy for three materials in terms of restoration of vertebral height, strength and stiffness after packing HA Block as compared with Polymethylmethacrylate Cement (PMMA) and alpha-tri-calcium phosphate cement (Biopex-R) in cadaveric study. By using thoracolumber spines derived from elderly human cadavers, two kinds of vertebral fracture models: Flat and Wedge were made on MTS 858 Mini. Restoration rate after packing each material was best for HA Block. The strength of HA Block was somewhat lower than PMMA and Biopex-R. It is suggested that HA Block had moderate and optimal strength to reduce stress to adjuscent vertebra and was enable to correct kyphosis in osteoporotic spine.