An internal analysis conducted by Johnson & Johnson in 2011 not long after it recalled a troubled hip implant estimated that the all-metal device would fail within five years in nearly 40 percent of patients who received it, newly disclosed court records show.
Johnson & Johnson never released those projections for the device, the Articular Surface Replacement, or A.S.R., which the company recalled in mid-2010. But at the same time that the medical products giant was performing that analysis, it was publicly playing down similar findings from a British implant registry about the device's early failure rate.
The company's analysis also suggests that the implant is likely to fail prematurely over the next few years in thousands more patients in addition to those who have already had painful and costly procedures to replace it.
The internal Johnson & Johnson analysis is among hundreds of internal company documents expected to become public as the first of over 10,000 lawsuits by patients who got an A.S.R. prepares to go to trial this week. The episode represents one of the biggest medical device failures in recent decades and the forthcoming trial is expected to shed light on what officials of Johnson & Johnson's DePuy Orthopaedics division knew about the device's problem before its recall and the actions they took or did not take.
(Read More: J&J Profits Beat Expectations as Drugs, Devices Deliver.)
The trial, which is expected to begin Friday in California Superior Court in Los Angeles, may also provide a guide to the consequences of the A.S.R. episode to Johnson & Johnson, both for the company's finances and its reputation. Last year, the company took a $3 billion special charge, much of it related to medical and legal costs associated with the device. DePuy has offered to pay patient costs for replacement procedures.
The A.S.R. belonged to a once-popular class of hip implants in which a device's cup and ball component were both made of metal. While the A.S.R. was the most failure-prone of those implants, surgeons have largely abandoned using such devices in standard hip replacement because their components can grind together, releasing metallic debris that damages a patient's tissue and bone.
On Friday, Judge J. Stephen Czuleger, who is presiding over the Los Angeles case, unsealed a number of motions that contained portions of pretrial depositions of DePuy officials as well as related company records. Those disclosures, like the company's estimate of the A.S.R.'s failure rate, represent only a tiny fraction of the information that will become public if the trial proceeds.
Over the last two years, plaintiffs' lawyers working on A.S.R.-related lawsuits have reviewed tens of thousands of internal DePuy documents and taken depositions from dozens of company executives.
Executives of DePuy have long insisted that their handling of the A.S.R. was forthright and appropriate. In mid-2010, when DePuy recalled the implant, officials said they were doing so because data that year from the National Joint Registry of England and Wales showed for the first time that it was failing prematurely at a higher rate than competing implants. In 2011, the British implant registry updated its projected failure rates for A.S.R. patients who had had it the longest, saying it was failing in one-third of them. It was that estimate that was challenged by DePuy.
About 7,000 of the A.S.R. lawsuits have been consolidated in a federal court in Ohio. An additional 2,000 cases have been consolidated in a California state court. The California case chosen to go to trial this week was selected because the plaintiff, a man named Loren Kransky, has cancer and may not live much longer, lawyers involved in the case said. DePuy has already settled a few A.S.R. cases before trial and it may choose to do so in Mr. Kransky's case as well.
About 93,000 patients worldwide received an A.S.R., about one-third of them in the United States.
There are two versions of the A.S.R., one used in standard hip implants and the other used in an alternative replacement procedure known as resurfacing. Only the standard implant was sold in the United States. Both versions of the A.S.R., however, used the same metal hip cup as part of their design.
Asked for comment about the company's internal analysis, a spokeswoman for DePuy, Mindy Tinsley, said in a statement that it "was based on a small, limited set of data that could not be used to generalize" the overall failure rate for the A.S.R.