A recent study of 293 patients implanted with the DePuy ASR acetabular cup, followed-up at an average duration of 3.2 years following implant surgery, noted that it has been recognized that the design of the ASR system makes it prone to unfavorable wear patterns. After statistical analysis of the clinical data collected from the patients, including measurement of cobalt and chromium ion blood levels in patients, the authors of the study, published in The Journal of Arthroplasty, a peer-reviewed journal, concluded the ASRs design shortcomings were most probably the cause of the high failure rate of the device.
“We conclude that the acetabular inclination angle is not a meaningful determinant of metal ion levels in metal-on-metal arthroplasty using the ASR system. The high failure rate of this system is more likely to be attributable to design flaws rather than modifiable surgical and technical factors.”
DePuy Orthopaedics has claimed in court proceedings that has been conducting, since the recall of the ASR in 2010, a root-cause analysis to determine why the ASR acetabular cup system has such a high failure rate compared to other hip replacement prostheses. However, DePuy says it has not completed its root-cause analysis and denies the that ASR is defective.
Thousands of patients have sued DePuy over the premature failure of their ASR hip implants.
By Gregg Borri
Gregg Borri is a trial lawyer actively involved in the ASR XL litigation in the United States. He can be reached at (888) 444-2336