12%, 37% or 49%? What Exactly Is DePuy’s All-Metal Hip Failure Rate At 5 Years

In short

Bloomberg has reported on the pre-trial testimony of Paul Voorhorst, a DePuy biostatistician, as a preamble to proceedings in the case of Loren Kransky vs J&J (DePuy), for which the jury sits tomorrow (Friday 25th January). In it, previously unseen documents suggest that the company’s own estimates of failure rate for some of its metal-on-metal hip prostheses are now as high as 37%, significantly higher than the 12 or 13% cited in the original recall notices.

Background

The full Bloomberg article can be found here. In it the author discusses the state of play as J&J’s DePuy business unit prepares for what is looking like a pivotal trial between plaintiff Loren Kransky and the company. According to Bloomberg, Claims by Kransky include failure to warn, negligent recall and manufacturing defect.

Whether the actual 5 year failure rate figure is ultimately critical or not remains to be seen, but the interesting newly revealed statistic of 37% comes from documents released by J&J preparatory to this trial and is three times that cited by the company in its recall. That figure had originally been estimated based on UK joint registry data, although a later estimate from the British Orthopaedic Association put the figure at an even higher 49%.

A spokesperson for DePuy commented, after the 37% figure had been acknowledged by DePuy’s biostatistician, that the company had only been looking out for its patients’ interests in analysing the data, and furthermore that it “was based on a small, limited set of data that could not be used to generalize the revision rate for ASR unlike published data from national joint registries that include large numbers of patients and detailed revision information.”

J&J has already offered to pay more than $200,000 to each of the estimated 10,000 implantees, a settlement figure that has reportedly been mostly rejected thus far. Indeed three cases have apparently already been settled at around the $600,ooo mark.

The proceedings are likely to be fascinating, there already being legal wranglings revolving around DePuy’s claimed reasons for the original recall and whether consulting clinicians can use the word “poisoning” to describe the impact of wear particles and consequent blood borne metal ions on the patient.

It seems J&J would prefer the jury looked at the patient’s history which has already been filed before the court and points out that “Kransky has smoked since he was 12, broke his back when he was 15, and was exposed to Agent Orange when he served as a U.S. Air Force mechanic in Vietnam. He suffers from diabetes, coronary artery disease, high blood pressure, and kidney disease. He had two strokes and suffers from kidney cancer.”

Source: Bloomberg