The DePuy Pinnacle Acetabular Cup System is a metal-on-metal hip implant which was meant to last longer and reduce the necessity of revision surgery, particularly among younger, more active recipients. Unfortunately, overall, the all-metal hip implants have had many more problems than expected. While the DePuy Pinnacle has not been recalled, DePuy is facing lawsuits regarding the Pinnacle which is actually an older design of the DePuy ASR all-metal hip implant.
Like the ASR, the DePuy Pinnacle Acetabular Cup System hip implant has a design which places a metal ball against a metal socket. The Pinnacle Acetabular Cup System has several variations including some with a metal liner. In patients who have a ceramic cup and a metal liner, revision surgery could be simpler, involving removal of the liner and replacement with a non-metal liner.
In metal-on-metal designs—including the metal liner of the Pinnacle—whenthe patient engages in normal, everyday activity, these two components rub against one another causing microscopic shards of cobalt and chromium to shear away from the implant, lodging in nearby tissues or entering into the bloodstream. These cobalt and chromium ions are extremely toxic to the human body although some bodies appear to tolerate moderate levels of these metals more readily than others.
Metallosis occurs when the cobalt and chromium ions build to a level which causes the surrounding tissues to become inflamed and painful. As the implant continues to shear away metal ions and they continue to enter tissues and bloodstream, bone loss and tissue death can occur as well as any of the following symptoms:
- Memory loss
- Neurological disorders
- Gastrointestinal disorders
- Renal failure
- Thyroid disorders
- Pseudo tumors
- Hearing and vision loss
- Dizziness and balance issues
- Chronic headaches
- Tingling and numbness in the extremities
Longer-term effects can include:
- Irreversible chromosomal damage
- Development of cancerous cells
- Increased lymphocytes in the body resulting in infection and illness
- The necessity for revision surgery to remove the implant as well as potential surgeries to remove pseudo tumors or infected bones
Although cobalt appears naturally in the body, it is present in very low levels of less than 0.41 micrograms per deciliter in the bloodstream. A study in the Journal of Bone and Joint surgery studied patients with all-metal hip implants and found levels of cobalt thirty-nine times higher than normal and chromium levels twenty-eight times higher than normal.
Because of the extremely high rate of failure and adverse symptoms in the all-metal hip implants, the odds that any person with a metal-on-metal hip implant will have trouble at some point is extremely high. Speak with your doctor about the risks, determine which type of metal implant you have, have regular blood tests done and speak with an attorney regarding your legal rights.