A married couple from Illinois has filed a metal-on-metal hip implant lawsuit against Howmedica Osteonics and Stryker Orthopaedics, two medical implant companies. Their metal hip implant lawsuit alleges that the company manufactured a defective hip implant, causing serious complications.

According to the text of their metal-on-metal hip implant lawsuit, plaintiff Darriel H. had a hip implant made by Stryker and Howmedica implanted in his body to replace his left hip joint in April of 2012.

However, the hip implant lawsuit, filed jointly by Darriel and his wife, co-plaintiff Debra H., asserts that Darriel developed near-constant pain in his hip, a reduced range of motion, and soon couldn’t sleep through the night due to the pain.

In October of 2012, Darriel’s physicians scanned his metal-on-metal hip implant with an M.R.I. and found that the metal-on-metal hip implant had created areas of metal debris around the implant. A blood test found elevated levels of cobalt — a metal from the Stryker hip implant — in Darriel’s blood.

Metal-on-metal hip implants are medical implants designed to replace the surfaces of the hip joint when they fail due to age, injury or illness. Most other hip implants have moving surfaces made out of polymer or ceramic, or even ivory in the oldest artificial hip implants.

In the 2000s, several different companies, including Howmedica and Stryker, came out with metal-on-metal hip implants. Since these hip implants were based on existing technology, they were able to exploit a U.S. Food and Drug Administration (FDA) testing rule called the 501(k) program.

According to the 501(k) program, a medical implant can skip most phases of FDA testing, so long as it is “substantially similar” to existing medical technology. While this program can save time and money, and get new medical devices on the market more quickly, in the case of metal-on-metal hip implants it may have let a dangerous device onto the market.

Stryker hip implant lawsuits like this one allege that metal-on-metal hip implants carry risks not seen in other types of hip implants. Allegedly, the action of the metal surfaces of the joint moving together can grind off microscopic metal particles.

Though the metal of the metal-on-metal hip implant is non-reactive when solid, when ground into tiny particles, it is more reactive, and may form toxic metal ions in tissues and in the blood.

Allegedly, this can cause painful reactions around the metal-on-metal hip implant, causing pain and the formation of growths called pseudotumors. Similar problems were reported across all brands and models of metal-on-metal hip implants, causing widespread hip implant recalls. The Stryker hip implant recall took place in June 2012, only months after Darriel received his Stryker hip implant.

Darriel had to have a revision surgery, a surgery where a failed hip implant is replaced. Revision surgery is more technically challenging than the initial hip replacement surgery, as there is less of the original bone left for surgeons to work with.

This, coupled with inflammation around the joint and scarring from the first surgery, increases the risk of complications for the new hip implant. Additionally, many patients develop problems in the other hip, as limping from hip implant problems may increase the stress on their other hip.

The Metal-on-Metal Hip Implant Lawsuit is Case No. 4560, in the U.S. District Court for the Northern District of Illinois.