Zimmer is a medical device company that creates a variety of orthopedic implants. In 2015, the company officially became Zimmer Biomet after buying Biomet for $13.4 billion. The acquisition made the new company the second-largest manufacturer in the orthopedic market.
The manufacturer promotes several hip products that use Zimmer Trabecular Metal Hip Technology. The three-dimensional material is supposed to simulate the body’s spongy bone to provide a high level of friction that helps the hip joint stabilize after being implanted. It also allows growth into the artificial hip implant.
The company’s top hip implant, the Continuum Acetabular System, uses Trabecular Metal Technology, Vivacity-E Highly Crosslinked Polyethylene and Biolox Ceramic Technology to create versatile acetabular cups in a range of sizes and options.
- A study published in the Journal of Bone and Joint Surgery concluded that the type of biomaterial used in Trabecular Metal Technology had “desirable characteristics for bone ingrowth.”
- A study published in Clinical Orthopaedics and Related Research found that Vivacity-E Highly Crosslinked Polyethylene “substantially improved the prognosis of patients after (total hip arthroplasty) for up to 13 years.”
- A 2006 analysis published in Seminars in Arthroplasty found zero evidence of clinical failures involving Biolox Ceramic Technology since the product was approved in 2000. The study concluded that the material was “a promising new addition to the orthopedic surgical community.”
Some Zimmer hip replacements use the company’s Kinectiv Modular-Neck Technology, which has four parts instead of three. The technology allows surgeons to choose unique sizes and shapes to match the patient’s needs.
Zimmer’s femoral components include:
- Zimmer M/L Taper with Kinectiv Technology
- Fitmore Hip Stem
- VerSys Epoch FullCoat Hip
Zimmer’s acetabular components include:
- Trabecular Metal Modular Acetabular System
- Trilogy Acetabular Hip System
Zimmer’s revision systems include:
- ZMR Hip, XL Revision Systems
- ZMR Taper, Porous Distal Stem
- Wagner SL Revision Hip Arcos
- One-piece Femoral Revision System
Zimmer no longer promotes products that use Metasul Metal-on-Metal articulation. Those hip joints were made from forged metal, instead of the cast metal used by traditional hip implants. The forged metal was supposed to be harder, smoother and more durable. But it was recalled when it was linked to complications when used with a Zimmer product that was nicknamed the Durom Cup.
Zimmer’s Durom Acetabular Component (Durom Cup)
The Durom Acetabular Component, commonly known as the Durom Cup, was Zimmer’s most problematic hip implant. The synthetic replacement for a natural acetabulum was made from a single piece of cobalt chromium alloy metal.
The acetabulum is the cavity at the bottom of the hipbone that’s shaped like a cup. The top of the thigh bone – also referred to as the head of the thigh bone, which is shaped like a ball – fits into the acetabulum. This ball-and-socket meeting creates the hip joint.
The Durom Cup was designed to address two problems with other artificial hip devices: durability and range of motion. Longer-lasting synthetic devices were needed to serve a younger patient demographic. Those younger patients often planned to live active lives, and they needed implants that provided superior range of motion compared to the ones traditionally given to older adults.
Zimmer believed the Durom Cup solved both problems. It was intended for use with the Zimmer Metasul Metal-on-Metal Tribological Solution LDH, providing a total metal hip replacement that was durable and had large diameter heads for maximum range of motion.
The FDA approved the Durom Cup for use in total hip replacements in 2006, and nearly 13,000 patients received the device. Problems began to surface within one year, and Zimmer briefly recalled the hip implant until it could teach surgeons how to implant it.
After updating the Zimmer product labeling and creating a surgical training program on its website, the company returned the Durom Cup to the U.S. market despite its problems. More than 1,700 people filed lawsuits against Zimmer, claiming the manufacturer marketed a dangerous product and failed to warn patients of the risks associated with the device.
Zimmer discontinued the Durom Cup in 2010, and the company has agreed to settle the majority of cases filed against it. However, the settlement process has not been finalized.
Despite ongoing litigation, Zimmer Biomet remains one of the largest companies in the hip implant market. The company controlled an estimated 31 percent of the market in 2016, more than any other company.