On the establishment of number-size distributions of wear debris from artificial hip joints with aerosol physics techniques

Karoline Mühlbacher
2014 unpublished
Aseptic loosening is the major cause for revision surgery of knee and hip arthroplasties, whereat wear is a common cause. The characterization of wear particles in terms of number and size is essential for the study of their biological effects on cells and indica- tion the need for possible revision surgery of artificial joints. The purpose of this study was to develop an efficient automated diagnostic method for number-size distribution of wear debris. In order to do so, metal debris was
more » ... ted from a hip simulator with a femoral head and acetabular cup (both CoCrMo) after 5 million cycles. The fluid samples were prepared and diluted with pure ethanol. The samples were analyzed by the electrospray method combined with a differential mobility analyzer, allowing particle detection ranging from several nanometers up to 1μm. This method was first intro- duced for measuring wear particles. Wear particles originating from metal-on-metal articulations were identified with a characteristic peak at 15 nm, using the electrospray setup. For calibration purposes of the method the same setup of aerosol particle characterization was used with de- fined polystyrene spheres of 102 nm diameter, which were successfully detected and measured in size. The presented electrospray-DMA setup - an automated counting and sizing method commonly applied in aerosol physics - was successfully used and validated for the first time to characterize wear debris from total joint replacement. The advantages of this diagnostic method over the conventional methods are its time and financial efficiency, low requirement of testing fluid (e.g. synovial fluid), and its suitability for the testing of different materials.
doi:10.25365/thesis.35090 fatcat:zwat2g6offgjbagtxp7paq2pcu