Total Hip Arthroplasty (Total Hip Replacement)

Total hip arthroplasty is the medical name for a total hip replacement. The surgeon removes the damaged ball at the top of the thigh bone and the damaged socket in the pelvis and replaces them with artificial components: a stem and ball on the femur side and a cup (often with a liner) in the pelvis. The National Institute of Arthritis and Musculoskeletal and Skin Diseases lists osteoarthritis, rheumatoid arthritis, osteonecrosis, and hip fractures among the reasons people need the surgery.

The parts can be combined in different ways: metal or ceramic balls, and cups lined with plastic (polyethylene), ceramic, or metal. The choice of materials is where most hip implant litigation comes from.

Metal-on-metal designs caused the biggest problems. The FDA explains that in these implants the metal ball and metal cup slide against each other during walking or running, which can release metal particles, and some metal ions such as cobalt and chromium enter the bloodstream. That debris can damage tissue around the joint (sometimes called metallosis) and lead to pain, implant loosening, and revision surgery. In 2016 the FDA began requiring metal-on-metal total hip systems to go through premarket approval, its strictest review. Lawsuits over recalled and metal-on-metal hips, and over corrosion at modular stem connections, produced some of the largest device settlements.

If you had a hip replacement and later needed revision surgery, the operative reports (which list implant makers and part numbers) and any blood tests for cobalt and chromium are key records. For how device cases are handled, see what is MDL and class action vs. mass tort. This page is general information, not medical advice.