Researchers in Adelaide, South Australia, have made an award-winning discovery in identifying a gene that causes the wearer of metal-on-metal (MOM) hip replacements to form painful lesions. Though the side effects of hip replacements can be severe, the medical breakthrough may allow researchers to create a screening test to identify if patients can safely receive an implant. 

Dr. Andrew Kurmis of Lyell McEwin Hospital is one of the researchers. In an interview with Austraila’s 9News, Kurmis said, “In Australia, we’re talking about tens of thousands of potentially exposed patients. Around the world, that number is in the millions.”

In the U.S., the FDA acknowledges that the fault with MOM hip replacements is the metal ball and metal socket that slide against one another during walking or running. This friction causes small particles of metal to flow into the bloodstream and ultimately build up in soft tissue, resulting in the very toxic condition known as metallosis.

Apart from metal poisoning, other signs and symptoms to look for that could plague MOM hip implant patients include:

  • General hypersensitivity reaction (skin rash)
  • Cardiomyopathy, or heart muscle disease. Symptoms include shortness of breath, swollen legs and feet and a bloated belly
  • Neurological changes, including sensory changes (auditory, or visual impairments)
  • Psychological status changes, including depression or cognitive impairment
  • Renal function impairment
  • Thyroid dysfunction, including neck discomfort, fatigue, weight gain, or feeling cold

The metals that compose these particular hip implants include nickel, cobalt, chromium, and titanium alloys, with stainless steel screws and plates. Despite the first metal allergy being reported in 1966, followed by subsequent well-documented studies, metal hip implant failure has remained generally unpredictable.

Manufacturers of MOM hip implants, Johnson and Johnson and DePuy Orthopaedics, have faced legal battles as recently as last year when DePuy was ordered to pay $247 million to six patients in Dallas, Texas who experienced severe adverse effects from MOM implants due to defective designs. Their injuries included tissue death and bone erosion.

Well over one million patients worldwide have undergone MOM hip implant procedures. This new discovery will no doubt save patients who possess the gene a lot of time in hospitals and a lot of time in pain.