The FDA further noted that patients who are at risk for “increased device wear and/or adverse local tissue reactions should be followed more closely.” Those identified as being at higher risk are:
- Women;
- Patients who are overweight or with high levels of physical activity;
- Patients with bilateral implants, resurfacing systems with small femoral heads (44 mm or smaller), suboptimal alignment of device components or suspected metal sensitivity (e.g., cobalt, chromium, nickel);
- Patients taking high doses of corticosteroids;
- Patients who have evidence of renal insufficiency; and
- Patients with suppressed immune systems.
“As a practicing rheumatologist, I would say [that for] any patient you see who has new-onset thyroid disease or unexplained heart failure and [has] either a metal-on-metal or metal-on-polyethylene joint, think about metal poisoning,” Dr. Bunning recommends. For rheumatologists, if a patient with an artificial hip has hip pain, “the usual reflex is to send [the patient] back to the orthopedic surgeon,” he says. However, rheumatologists also may opt to order a cobalt level or MRI with the appropriate sequences. If cobalt levels come back elevated or the MRI is abnormal, he says, it’s appropriate to work together with the orthopedic surgeon to manage the patient’s treatment.
Kimberly J. Retzlaff is a medical journalist based in Denver.
Acknowledgment: The author and The Rheumatologist thank Dr. Bunning for his assistance in the development of this story.
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