Risk of cancer in first seven years after metal-on-metal hip replacement compared with other bearings and general population: linkage study between the National Joint Registry of England and Wales and hospital episode statistics.

To determine whether use of metal-on-metal bearing surfaces is associated with an increased risk of a diagnosis of cancer in the early years after total hip replacement and specifically with an increase in malignant melanoma and haematological, prostate, and renal tract cancers.