Many patients have undergone hip revision surgery due to the premature failure of metal on metal hip replacements.

While most hip replacement products implanted today should last 20 years or more, a number of metal on metal hip systems have failed one to five years after implantation.

A metal on metal hip product consists of a metal ball and a metal socket. These systems originally were created with the belief that because metal is sturdier than plastic, the metal on metal hip systems would last longer.

Many metal on metal hip replacement systems were advertised to help relatively younger, more active patients return to their busy, athletic lifestyles.

A study from the U.K. showed 6.2 percent of metal on metal hip systems required replacement within five years. The study was led by Ashley W. Blom, MD, Ph.D., professor of orthopedic surgery at the University of Bristol in the U.K.

The revision rate for women was three or four times higher than those with non-metal implants. Men saw a revision rate two to three times higher than with non-metal systems.

Researchers said that women tend to be more sensitive to metal and that their implants might be implanted at angles that cause more wear to the metal surfaces. In addition, women are more apt to be victims of osteoporosis. The weaker bones can be more susceptible to problems induced by reactions to the metals. 

The metals used are generally cobalt and chromium. Over time, the metal parts rub together and release small particles that settle into nearby tissue. The affected tissue reacts by becoming inflamed, and the body might try to eliminate the particles by sending fluid to the area in an effort to flush them away. The fluid can collect, becoming a painful pseudotumor.

Metal ions can also enter the bloodstream, causing metal poisoning.

Starting in 2004, the manufacturers of metal on metal hip systems started designing the products with larger heads because mechanical models indicated a larger head could cut down on the amount of wear to the joint parts and reduce the likelihood of dislocation. Dr. Blom’s study showed that the implants with the oversized heads actually have failed more rapidly than those with smaller heads.

Dangers of Metal on Metal Hip Replacement Revision Surgeries

If you have undergone a revision surgery due to the premature failure of a metal on metal hip system, you could be eligible for compensation through legal representation.

Several brands of metal on metal hip system has been linked to common problems, such as:

• Dislocated hip
• Chromium or cobalt poisoning
• Cancer
• Degenerative heart disease or cardiomyopathy
• Loss of bone strength, leading to fractures
• Tissue death of nearby tissue affected by metal fragments
• Pseudotumors made of fluid around the implant
• Early failure of the artificial hip system

According to the American Academy of Orthopaedic Surgeons, complications of revision surgery include leg-length inequity, unusual bone formations, fractures, nerve or blood vessel damage and implant loosening. In addition, the patient undergoing a revision surgery has a higher risk of infection, blood clots and a pulmonary embolism, which is a blood clot in the lungs.