Non-destructive and non-invasive observation of friction and wear of humanjoints and of fracture initiation by acoustic emission

Quality control in orthopaedic diagnostics according to DIN EN ISO 9000ff r equires methods of non-destructive process control, which do not harm the p atient by radiation or by invasive examinations. To obtain an improvement i n health economy, quality-controlled and non-destructive measurements have to be introduced into the diagnostics and therapy of human joints and bones . A non-invasive evaluation of the state of wear of human joints and of the cracking tendency of bones is, as of today's point of knowledge, not estab lished. The analysis of acoustic emission signals allows the prediction of bone rup ture far below the fracture load. The evaluation of dry and wet bone sample s revealed that it is possible to conclude from crack initiation to the bon e strength and thus to predict the probability of bone rupture.