FDA warns against using Synovo total hip replacement implants

The FDA is urging healthcare providers to stop purchasing and implanting a total hip replacement system sold by Synovo and recommended that orthopedic surgeons remove all components from their inventories.

In its notice, the agency said that parts of the implant have been “significantly modified” in the 30-odd years since it went through federal review and first received a regulatory clearance in 1991. 

The FDA is also providing care guidance for patients who may have had a procedure employing the company’s femoral resurfacing cup, acetabular fixation cup or acetabular bearings since 2019—some of which are sold as stand-alone products. The total hip system has also been referred to as the Synovo Preserve and the Endotec BP, the agency said.

The FDA said it became aware of the implant’s hardware modifications in 2022, and issued Synovo a warning letter in March 2023. 

At that time, inspectors pointed to changes in the company’s femoral resurfacing cup, which had originally been cleared with a caveat that it could not be promoted for use without bone cement. However, they said they found instructions directing users that the implant now had a coating allowing it to be used in cementless fixation.

“The referenced changes, individually and collectively, are likely to expose patients to increased risks of loosening and subsequent revision surgery (e.g., from pain, proximal femur fracture, or component fracture),” the warning letter said. 

The letter also said the California-based company had been marketing some of the system’s components without first obtaining premarket approval, and it directed the company to halt manufacturing immediately.

“Based on currently available information, the FDA does not recommend [surgical] removal of Synovo Total Hip Systems from patients who do not have any new or worsening pain or symptoms,” the agency said in its January 3 notice.

The FDA said that patients should be closely monitored, including through X-rays, for potential bone loss, implant loosening or suspected device failure. Patients should also contact their providers if they have new or worsening pain, grinding or other noise, or weakness of the hip or knee on the side of the implant.