Vertebroplasty is a minimal invasive technique in the management of osteoporotic vertebral fractures. Clinical and biomechanical investigations could show the strengthening effect of the unipedicular injection of osteoporotic vertebral bodies using different materials. Little is known about the distribution of the inhected material and the resulting biomechanical outcome. The present study was designed with the focus on investigating both, the biomechanical behaviour and the cement distribution in augmentation of osteoporotic vertebrae using the vertebroplasty technique.

40 osteoporotic vertebral bodies were injected unipedicular with an amount of 6ml of two different PMMA bone cements (Vertebroplastik/DePuy; Simplex/Stryker-Howmedica-Osteonics). Strength and stiffness were measured during axial compression. For the investigation of the cement distribution, two sections of each injected vertebral body were cut, digitally imaged and analysed by an image processing software using a specially developed procedure.

The augmentation with Vertebroplastik bone cement resulted in a significant increased failure load compared to control. The use of both cements showed a significant increased resistance to further compression fractures. For the Vertebroplastik bone cement a significant better flow to the centre of the vertebral body was observed.

Vertebroplasty of osteoporotic vertebral bodies by using Vertebroplastik and Simplex PMMA bone cement results in significant increased failure load and resistance to further compression under laboratory conditions. The investigation of the cement distribution showed a significant better spreading of the Vertebroplastik bone cement to the centre of the vertebral body.

From the experimental point of view we recommend the augmentation of osteoporotic vertebral bodies to prevent further collapse.