Zimmer Inc.’s Orthopaedic Hip Replacements: Successes and Failures
The Durom Acetabular Component system or “Durom Cup”, by Zimmer, was praised as an innovation for patients suffering from arthritic hips when it first entered the market in 2006. Now just a few years later the company is facing Zimmer hip lawsuits from patients who suffered Durom Cup hip failure as well as lawsuits from investors who argue that the company did not disclose to them that the hip replacement device was defective.
Suspension of Zimmer Durom Cup sales
While there was no actual Zimmer hip recall, the device was voluntarily withdrawn from the market in 2008 with the company stating that the instructions for use and surgical technique were inadequate. Zimmer stated in a letter sent to surgeons that it would suspend marketing and distribution of the Durom Cup in the U.S. while they updated product labeling and provided more detailed surgical technique instructions. They also stated that they would implement a surgical training program for U.S. surgeons with regards to this product.
The Durom Cup was eventually re-released to the public. Today, patients continue to have the device implanted. While the results are successful for many, others continue to suffer hip failure. It is those individuals who are adding to the growing number of Zimmer hip lawsuit filings.
Other Zimmer hip replacement products
Zimmer Holdings, Inc. is a medical device company founded in 1927, and is headquartered in Warsaw, IN. The company invents, develops, markets and manufactures medical devices which include orthopaedic, spinal and trauma devices, dental implants, and other related orthopaedic surgical materials.
Listed on the company’s website are several hip replacement products they currently offer which include:
- M/L Taper Hip Prosthesis
- The M/L Taper Hip Prosthesis with Kinectiv modular neck technology is unlike traditional implants that are limited in size and shape. This product offers more options for a more accurate fit through its four part design allowing surgeons the ability to separately select each component for an optimal fit.
- Fitmore Hip Stem
- The Fitmore Hip Stem is used in minimally invasive procedures and hip replacement with this system uses a muscle-sparing technique which reduces recovery time.
- Continuum Acetabular system
- The Continuum Acetabular system offers Trabecular Metal technology which is not a coating but rather a 3D material that resembles the body’s own natural “spongy” or cancellous bone. It is made of tantalum metal which has a high friction level, and a high porosity that allows for bone in-growth.
- Metasul Metal-on-Metal articulation
- The Metasul is a metal-on-metal system that offers long-lasting durability. It is forged metal and not cast which makes it harder and smoother.
A look at the Zimmer Durom Cup hip failure
The Durom Cup was designed as a monoblock cup made of a cobalt chromium alloy with pure titanium plasma sprayed coating for fixation. Its design and material were the key elements expected to provide stability, wear resistance, and bone-sparing. Many surgeons, however, reported a higher than expected rate of cup loosening in patients which resulted in revision surgery.
The main symptom of loosening reported was radiating pain from the hip or groin. Dr. Lawrence Dorr was the first to publicly recognize a problem with the Durom Cup. In April 2008 he sent a letter to the members of the American Association of Hip and Knee Surgeons (AAHKS), explaining the problems he had experienced implanting the Durom Cup. He cited that out of 165 Durom Cup hip replacements he had performed, as many as ten to fourteen patients required revision surgery.
Though the company appears to have many promising products on the market, the reported failure rate of the Durom Acetabular Component has many questioning the safety the Zimmer product. However, to-date the failures and revision surgeries alleged in the Zimmer hip lawsuits relate only the Durom Acetabular Component or “Durom Cup”.