Allergy to Metal Orthopedic Implants

Metal implants are used in a variety of orthopedic surgical settings, including fracture repair and joint replacement surgery. Some people have allergies or sensitivities to metal and others may worry about developing one. These are rarely problems when it comes to implants.

Hypersensitivity or allergy can occur after contact with various metals.

While the words "hypersensitivity" and "allergy" are often used interchangeably, they're not really the same. That said, in the discussion of metal implants in the body, these words are often used in the same discussion. 

Some people are prone to developing a response to various metals, such as skin sensitivity to jewelry or watches. 

Whether a similar sensitivity may develop to metal implanted inside the body—where it doesn't touch the skin—isn't yet well understood, but there is some evidence it can happen.

Common Implant Metals

The most common metals used in orthopedic implants are:

• Cobalt-chrome
• Stainless steel
• Titanium

In general, orthopedic implants are alloys, meaning they contain more than one type of metal. The base metal(s) are found in the highest quantities, but smaller amounts of other metals, such as nickel and aluminum, are often used.

Many people have known skin sensitivities to various metals. One frequently encountered metal sensitivity is to nickel. Some orthopedic implants contain small amounts of nickel, and there's been a concern that this may be an issue for nickel-sensitive people.

Metal Allergy and Implants

Metal sensitivities and allergies have been implicated in some situations involving pain or problems with orthopedic implants. While the potential for a reaction exists, it's thought to be extremely rare.

Pain around the site of orthopedic implants has many causes, and before blame can be assigned to metal sensitivity or allergy, a thorough investigation must occur.

Unfortunately, the symptoms of metal implant sensitivity and allergy are not well defined.

Having a skin sensitivity to a particular metal is not thought to correlate well to having sensitivities to implanted metals. Therefore, to diagnose a sensitivity or allergy to a metal implant usually requires that the implant be removed.

Skin Sensitivity to Nickel

Between 10% and 15% of the general population is sensitive or allergic to nickel. If that includes you, make sure your doctor knows. They may want to consider an implant made of different materials, such as titanium.

This may not always be possible, and an implant made with nickel may be the most appropriate implant available for your condition.

Fortunately, the chance of developing problems with metal implants, even in people with known skin sensitivities, is extremely low.

Should I Have My Metal Implant Removed?

It's rare for someone to need their metal implants removed due to a metal allergy or sensitivity. While that's nice to know, cases have been reported, and some people's symptoms have gone away after removal.

However, because this can involve another surgery that may be quite complicated, your doctor can help you determine the cause of your problems and the appropriate treatment to consider.

Fortunately, people who's implant problems were a clear result of metal sensitivity usually find immediate relief after removal.

Some implants are made of non-metal materials, such as ceramics, but there's limited data about their effectiveness and longevity. Therefore, these materials are generally used only when metal implants have been removed, or if you have a high likelihood of problems with a metal implant.