Particles from hip, knee, or shoulder replacements can reach the brain but were not linked to declining memory or thinking skills, according to a study of 701 older adults published in the journal Acta Biomaterialia. Researchers at Rush University in Chicago did find that cobalt, a key element of most implants, was associated with more Alzheimer's disease-related changes in the brain, HealthDay reported in its summary of the Rush findings.
That combination is reassuring but not the final word. The study was observational, it cannot show that cobalt caused any brain change, and the researchers say more work is needed.
