DePuy (pronounced DePew) Orthopaedics began a new phase of research in the late 1990s; more and more hip replacements were being performed on younger patients, and the company was looking to create a more durable product with a longer lifespan. Research and development efforts introduced a family of products starting in 2000 that had great promise; unfortunately, trouble was on the horizon.
A great idea with serious problems
The product lineup, which included the Pinnacle Hip Replacement System, the ASR XL Acetabular System total hip replacement and the ASR Hip Resurfacing System, featured a metal-on-metal (MoM) option intended to provide more flexibility and durability for younger patients. Unfortunately, the design had serious flaws.
Problems began to arise very shortly; revision surgery was necessary to correct pain, grinding, bone fractures, and dislocations (among other issues). A major complication was metallosis, or heavy metal poisoning, a result of the MoM contact. Metallosis is the result of friction in the joint that releases cobalt ions into the surrounding tissue, requiring surgical intervention to correct. Metallosis can cause:
- Cardiomyopathy (heart problems), including heart failure
- Visual impairment that may lead to blindness
- Cognitive impairment
- Nerve problems
- Thyroid problems
- Auditory impairment that may lead to deafness
- Necrosis (tissue or bone death)
- Skin rashes
Worse, research recently presented at the Annual Meeting of the American Academy of Orthopaedic Surgeons found a correlation between the DePuy implants and heart failure. According to Healio, “Men who underwent primary hip arthroplasty with a specific, conventional large-head metal-on-metal implant by a single manufacturer