For years, DePuy has been blaming the doctors who use their ASR products for the ever-growing failure rate. Ongoing quotes from DePuy’s ASR spokespersons informed the media that failures were attributed to doctors not following directions. DePuy ASR even blamed patients, claiming that they were “careless and at fault” and claiming that the victims of the DePuy ASR recall “conducted themselves so as to contribute substantially to their own injuries and damages.”
Thousands of DePuy ASR victims now face the possibility of hip replacement complications and a painful and risky surgery to replace it. According to a study from Rostock, Germany, “Implant infection remains a fear with hip replacement complications. A higher rate of infection is observed after revision surgery.” This raises the stakes for hospitals and surgeons alike as revision surgery is multiplied by DePuy ASR hip replacement complications victims.
Some orthopedic specialists believe that DePuy’s design of the ASR cup is the reason for the failures. DePuy’s ASR cup is shallower than some other hip implants, and that may be the reason why DePuy’s ASR system has such a high failure rate. Dr. Harlan C. Amstutz, an orthopedic surgeon in Los Angeles who designs hip implants for another orthopedics company, said that he believed that DePuy’s ASR design is prone to problems.
Data from the National Joint Registry (NJR) of England and Wales shows the five year revision rate for the ASR™ Hip Resurfacing System is approximately 12 percent and for the ASR™ XL Acetabular System is approximately 13 percent. These revision rates are across the entire size range. The risk for revision was highest with ASR head sizes below 50 mm in diameter and among female patients.
For comparison purposes, Pietro Melloni, MD, PhD, and Rafael Valls, MD reviewed 1854 hip replacement patients in 2005 (from 36 to 91 years old; male/female ratio 1:3) who underwent hip replacement in an eight-year period revealed that 5.2% experienced acute hip replacement complications and 9.2 developed hip replacement complications as long as 15 years later. Comparing these failure rates and the fact that materials used today are more advanced, explains the importance of DePuy’s ASR recall.
Mechanical loosening is the most typical hip replacement complications and indication for the need of repeat surgery. Dislocation or luxation of hip arthroplasties can be caused by a patient’s poor muscle tone, subsequent trauma, or positional factors and is more common in revision surgeries.
Acute hip replacement complications can include:
- Cement extrusion
- Immediate dislocation
Late hip replacement complications that can occur as long as 15 years after surgery can include:
- aseptic loosening
- aggressive granulomatosis,
- stress shielding
- heterotopic ossification
- bone fractures
- and prosthetic fracture
Strength of Implant Material
An artificial hip generally lasts 12-15 years and in some cases up to 30 years with the strong materials used today. For example, ceramic-based material was tested and showed to withstand the weight of a small boat.
- Infection can occur in 1% of artificial hip replacement complications and can be seen right away or months or even years after surgery take place. Sinus tract formation or bone destruction may occur with more aggressive infectious agents.
- Extensive bone destruction, air in the soft tissue and/or joint, extensive or aggressive periosteal reaction.
- Polymethyl metacrylate cement extrusion usually means a defect in the medial acetabular wall.
- Intraoperative or acute fracture is a rare complication in the primary cemented prostheses.
- Aggressive granulomatosis, also known as particle or cement disease is caused by macrophage reaction on either the acetabular or femoral side of the arthroplasty.
- Heterotopic calcification is relatively common and found in 15 to 50 percent of cases and is usually asymptomatic. It can appear a few weeks after hip replacement complications surgery or take two years to mature.
For information on the 2012 Stryker hip implant recall, please visit https://www.seegerweiss.com/stryker-hip-recall.