Metal Allergy to Surgical Plates, Screws, and Implants

Having a metal allergy or sensitivity doesn't mean getting a metal implant like a surgical screw, plate, or joint replacement is entirely off limits or that the body will reject it. But while reactions to surgical hardware and implants are rare, they do sometimes occur.

This article explores metals commonly used in medical devices, possible sensitivities and allergies, symptoms that may occur with a metal allergy, and when removal may be recommended.

Metal Allergies and Hypersensitivies

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.

Metals Commonly Used in Implants

The most common metals used in orthopedic implants are:

• Cobalt-chrome
• Stainless steel
• Titanium

Solid metal implants include orthopedic plates and screws. In general, orthopedic implants are alloys, meaning they contain more than one type of metal. The base metals 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.

Nickel

Between 10% and 15% of the general population is sensitive or allergic to nickel. If that includes you, make sure your healthcare provider 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.

Other Materials

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.

Reactions to Surgical Hardware 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 low.

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

Symptoms of a Reaction

Unfortunately, the symptoms of metal implant sensitivity and allergy are not well defined. Symptoms reported have included:

• Anemia
• Weakness
• Numbness
• Pain

Having a skin sensitivity to a particular metal is not thought to correlate well to having sensitivities to implanted metals.

Therefore, diagnosing a sensitivity or allergy to a metal implant usually requires that the implant be removed.

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. Still, cases have been reported, and some people's symptoms have gone away after removal.

Because this can involve another surgery that may be quite complicated, it should not be done without a thorough review of the pros and cons. Your healthcare provider 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.