Orthopedic Implants and Metal Sensitivity
In this article, Dr. John Sperling discusses some basic information surrounding orthopedic surgery and metal sensitivity.
In this article, Dr. John Sperling discusses some basic information surrounding orthopedic surgery and metal sensitivity.
Metal sensitivity is a concern among some patients considering total joint replacement surgery for the treatment of their arthritis. When looking at the information available on this topic, it becomes clear that this is an area of significant controversy with, perhaps, more questions than answers.
While it has been noted that up to 15% of the general population may have a skin sensitivity to a specific type of metal1, it’s poorly understood how common a problem this may be among patients who have undergone an orthopedic procedure where metal is implanted inside their body. In this article, we’ll discuss some of the information that’s currently available around this topic and discuss some of the options available for patients.
It has been recognized that when metal is placed inside a person (a live biologic system) some microscopic corrosion of the metal may occur over time. This corrosion process results in the development of extremely small microscopic metal ions. These very small metal ions may, or may not, subsequently stimulate the immune system in the body.
Additionally, it’s known that the material that results from implants being inside the body can become associated with skin inflammation in a small subset of patients.
Therefore, if a patient has signs or symptoms of inflammation or an allergic response after having metal placed inside their body, sensitivity to that specific metal may be considered.
One challenge when thinking of metal sensitivity, however, is that there isn’t a widely accepted test available to determine if a patient has a true metal sensitivity or not. Traditionally, skin patch testing has been performed to test for metal sensitivity. In this type of testing, a patch may be applied to the skin for two to four days containing a variety of substances to test skin sensitivity to specific materials. However, the true value of this test in predicting whether an individual patient may have a true reaction to an implant made of a specific metal implanted in their body has been debated without a clear answer.
Nickel is one of the most common types of metal sensitivity.2 In order to attempt to address this potential concern, some orthopedic implant manufacturers have developed joint replacement implants that are noted to be nickel-free. This may be an option for you and one that you can discuss with your surgeon.
Metal sensitivity is clearly an area where a significant number of questions remain. It’s best to discuss your specific circumstances with your surgeon prior to surgery. Together, with your surgeon, you can decide whether testing is appropriate to consider and whether special components may be used at the time of your surgery.