MIXTURES FOR VERTEBROPLASTY: THE FLOWABILITY OF THEIR COMPONENTS AND A NEW PRODUCTION TECHNOLOGY USING A CENTRIFUGAL MIXER

The article deals with the production of bone cement, which is used in various fields of medicine. A new technology for producing medical cement mixtures is presented. Particular attention is paid to use of bone cement in the treatment of vertebral compression fractures associated with osteoporosis. The incidence rate of osteoporosis and its clinical manifestations is expected to increase four times in the next half-century due to the growth of population and the increase in life expectancy. Problems of contemporary medicine that are associated with obtaining granular mixtures of preset quality and composition are discussed. Information about the flowability of the components of cement mixtures is presented. The concept of a criterion of flowability is introduced for the first time for rationally choosing a mixing method according to the flowability of the components for preparing quality cement mixtures. Flowability data for cement mixture components have been obtained to optimize the mixing process. A dimensionless equation is set up to calculate the power requirement for the mixing process. The quality of the resulting granular compositions depends primarily on the physicomechanical properties of the materials being mixed. A continuous, centrifugal, bone cement mixing unit is described, and the principle of its operation is considered. The performance of continuous mixers has been evaluated in terms of output capacity, specific energy consumption, and heterogeneity coefficient. The new, centrifugal mixer has been demonstrated to be more efficient in bone cement production than the pulsating mixer.