The invention of the metal-on-metal total hip replacement was innovative in that it allowed the recipient to be more active than those who received other kinds of hip replacements on account of its greater range of motion and greater propensity for activity. Ironically, movement is precisely the issue with most metal-on-metal hip replacements. As one moves their new hip through even the most basic of motions, such as walking, the metal ball and the metal socket rub against each other. This causes minute metallic particles, or ions, of the replacement to be shaved off of the device and land in the surrounding tissues and bone. An estimated 100,000 to 1,000,000 ions flake off of the hip replacement with every step the person takes.
Most hip replacements contain some combination of cobalt, titanium, and/or chromium among other metals, and while certain levels of metals are needed in the body to maintain proper homeostasis, heightened levels caused by this flaking can be toxic. In fact, the World Health Organization has classified certain levels of cobalt and chromium as carcinogens. Harmful levels of these metals inside the body causes a condition known as metallosis, or metal poisoning. Symptoms of metallosis that affect the implantation site include severe pain, joint loosening, and even total replacement failure, in some extreme cases. The disease is easily recognizable because the metal ions will deprive the affected tissues of oxygen and cause them to turn gray. Metallosis can cause the health of the patient to deteriorate outside of the surgical site itself, too. It is the body’s job to remove any foreign particles such as these through the immune and endocrine systems. As a result, the ions find themselves in the blood stream and are transported to different parts of the body, inhibiting their various functions. Neurological problems are not uncommon for those with metallosis. Patients may start to develop emotional instability, headaches, and memory or other cognitive issues. Deafness, blindness, and cardiovascular issues have also been reported due to metallosis.
The obvious solution to treat this disease is to remove the hip replacement and swap it with one of a different metallic composition. That being said, the cellular damage that the ions do to the bones and tissues around the replacement, called necrosis, can make additional surgery complicated and dangerous. The body can only remove the ions so fast, and if there is a buildup, it can result in pseudotumors. These are pockets of liquid and metal particles usually formed in the dead tissue around the surgical site and can further complicate the surgery. Medication is available as a treatment that will binds to the ions. It makes it easier for them to be absorbed into the blood stream and expelled through one’s urine. Everyone’s body will react differently to the particles; some will have very strong reactions, while some have no reaction at all.
The Food and Drug Administration has recalled three different brands of metal-on-metal hip replacements, although every brand of replacement has the potential to cause issues for the patient. These three are: the Smith & Nephew R3 Metal Liners of the R3 Acetabular System, the Zimmer Durom® Acetabular Component, and the DePuy ASR TM XL Acetabular System (DePuy being a subsidiary of Johnson & Johnson). If you have had a metal-on-metal total hip replacement and have suffered from one or more of the following symptoms, you may have a case against its manufacturer. Call the Wyoming Hip Implant Injury Attorneys today at the Ochs Law Firm to set up a consultation.