Pharmaceutical

Failure of metal-on-metal hip implants causing pain for patients

 Failure of metal on metal hip implants causing pain for patientsScott Ebert, 48, was so happy to experience relief from pain after receiving a new artificial hip made by Stryker that he named his new puppy after the medical device company. But two months later, Ebert was singing a different tune.

Ebert’s artificial joint began slipping, causing his leg to give out unexpectedly. Sharp pains stabbed at his foot, and a sizeable bruise covered his calf. His hip burned with pain, his ears rang. Ebert rattled off an odd list of symptoms that only baffled his doctor, until he drew Ebert’s blood.

Ebert’s artificial hip, known as the Rejuvenate, was corroding within his body and leeching metal ions into his bloodstream. This type of blood poisoning is known as metallosis, and it is a phenomenon that has become associated with a new type of hip implant – ones made with metal parts that can rub together, accelerating wear and causing the device to corrode.

Short-term effects of metallosis include fatigue, headaches and other problems, but the long-term effects are still unknown. Research has shown that metallosis can damage DNA, which can lead to complications such as cancer.

The problem with so-called metal-on-metal hip replacement systems first came to light in 2010, when DePuy Orthopaedics, a subsidiary of Johnson & Johnson, issued a worldwide recall on its ASR hip replacement and hip resurfacing systems after reports of early failures. Metallosis was later found to be an issue with patients who received the devices.

Medical professionals, regulatory agencies and patients alike were warned that metal-on-metal hip implants made by other manufacturers could also cause similar injuries. Last July, Stryker issued a recall of its Rejuvenate and ABGII modular systems because of premature failures and reports of heavy metal in patients’ bloodstreams.

Six months after receiving his Stryker hip implant, Ebert had to have revision surgery to remove and replace his defective device. Revision surgeries tend to be more invasive and the recovery time long. Ebert now suffers with chronic pain.

Source: MedicalXpress