March 13, 2012 6:52 am Need a New Hip? Avoid Metal on Metal New study shows that metal-on-metal hip replacement is falling at much higher rates than other types. The study author even suggest a ban. US & World Videos 1:43 Traces of bird flu virus found in 1 in 5 samples of pasteurized milk, FDA says 2:42 Mother, surrogate celebrate a perfect ending to their long journey 1:12 Watch: Why vaccines are contributing to improved public health 1:53 The Helix School in San Rafael growing with the community 3:33 Bay Area sees slight improvement in air quality, annual report shows