<p>A revolutionary medical technique using sound waves to identify osteoarthritis in the knee has been developed by researchers.</p><p>The UK is leading this new field of health research based on listening to the sounds emitted by the body.</p><p>Microphones are attached to the knees of patients, and the high frequency sound waves emanating from their knees are measured as they stand up. These acoustic emissions are interpreted by computer software to give information about the health of the patient's knee.</p>