The US Food and Drug Administration (FDA) approved on June 13 the first ceramic-on-metal total artificial hip system for patients with osteoarthritis.

Hip joints consist of bone in the shape of a ball at the top of the thighbone (femur) that fits into a rounded socket in the pelvis (acetabulum). During total hip replacement surgery, worn and damaged portions of bone and cartilage are removed and replaced with an artificial hip joint.

Specifically, a shell or cup replaces the socket, a stem is inserted into the thighbone and a femoral head or ball at the top of the stem is fitted inside the curved artificial socket where the ball can slide around, allowing for movement.

Previous total hip replacement systems cleared or approved by FDA have used different combinations of metal, ceramic, and polyethylene (a form of plastic). The Pinnacle CoMplete Acetabular Hip System is the first to combine a ceramic ball and a metal socket.

“Orthopaedic surgeons and their patients now have an additional option for total hip replacement with the approval of the Pinnacle CoMplete Acetabular Hip System,” said Christy Foreman, director of the Office of Device Evaluation in the FDA’s Centre for Devices and Radiological Health.

The FDA’s approval is based on a two-year, randomized clinical trial, which found no clinical difference between 194 patients who received the new ceramic-on-metal system and 196 patients in a control group who received a metal-on-metal hip implant. Two patients who received the Pinnacle CoMplete system required a second surgery to replace their new implant compared with three patients who required a second surgery in the control group.

As a condition of FDA approval, the manufacturer, DePuy Orthopaedics Inc., will conduct a postmarket study, monitoring patients receiving the Pinnacle CoMplete system for adverse events and metal ion concentrations in their blood.

DePuy is located in Warsaw, Indiana.