US Clinical Trials for the Polymotion Hip Resurfacing (PHR) System Started. Read here for all the information about the clinical trial and the 7 sites in the US that are participating. This is good news for women who want a hip resurfacing and for those worried about high metal ions. https://surfacehippy.info/us-clinical-trials-for-polymotion-hip-resurfacing-phr-system-started/ (https://surfacehippy.info/us-clinical-trials-for-polymotion-hip-resurfacing-phr-system-started/)