WASHINGTON – Hundreds of people who say they've been harmed by a Medtronic spinal device are pursuing a new legal pathway around rulings that have kept them from getting a day in court.

They argue that the Food and Drug Administration, which approved limited use of the Infuse bone growth product in 2002, offered a 2008 warning to doctors about "life-threatening complications" from unapproved applications. Then, the Spine Journal in 2011 and the U.S. Senate Finance Committee in 2012 each harshly criticized Medtronic for allegedly paying physicians hundreds of millions of dollars to write scholarly articles about Infuse while editing those articles to downplay Infuse's dangers.

Yet for all the claims of poor performance, dangerous outcomes and shoddy scholarship, Infuse has never been the subject of a personal-injury trial because of a legal concept called "pre-emption." That means federal law takes precedence over state law. The Supreme Court has extended this premise to say that almost no one can sue for damages caused by medical devices that received premarket approval from the FDA.

Now, hundreds of new lawsuits — including dozens in Minnesota — aim to find a way around that obstacle by accusing Medtronic of illegally promoting uses of Infuse that differ from what the FDA specifically approved.

If the allegation is upheld, legal experts say the world's biggest medical device maker could find itself awash in settlements or judgments that could push the entire medical device industry into a new era of corporate liability.

"The cases are important," said Prof. David Prince of the William Mitchell College of Law. "The whole area of law certainly doesn't make sense, especially to consumers."

Medtronic declined a Star Tribune request for an interview, but issued a statement that denied any wrongdoing and disputed "any suggestion that the company improperly influenced or authored any of the peer-reviewed published manuscripts discussed in the [Senate] report, or that Medtronic intended to under-report adverse events."

Landmark case

Judges have ruled that pre-emption requires them to throw out Infuse cases before a jury hears evidence. Their decisions are based on a landmark 2008 case, Riegel vs. Medtronic, in which the Supreme Court ruled that patients generally are forbidden from suing device manufacturers because that would let state courts trump federal regulators who review clinical test results and let devices onto the market.

In the case of Infuse, however, patients' lawyers think they have found a way to get to trial by linking Medtronic to so-called "off-label" uses that the FDA did not approve.

Doctors can legally use devices in off-label applications, and federal health statistics show that Infuse is used off-label 85 percent of the time. Jennifer Fuson, a spokesman for the American Association for Justice, said a critical question is who is responsible "if you are injured by a product that was used in a way not approved by the FDA?"

The Department of Justice dropped a criminal investigation of Medtronic's off-label promotion of Infuse without explanation in May 2012 and did not respond to a request for comment.

In a statement, the FDA declined to say if it has investigated the promotion of Infuse.

"Promotional materials are unlawful if they promote an unapproved use for the product; contain claims relating to the dosing, safety or effectiveness of the product that are inconsistent with the approved labeling; or if they lack a fair and balanced presentation of information, i.e., of benefits and risks," the agency said.

In a December 2012 report, the Senate Finance Committee claimed that Medtronic employees, including some in the marketing department, wrote, edited and otherwise influenced the content of scholarly articles about Infuse written by doctors who were collectively paid $210 million by Medtronic from November 1996 through December 2010.

A spokesman for the Finance Committee declined to say whether Chairman Max Baucus, D-Mont., thought Medtronic violated any regulations or laws. "The editing of the journal articles and large payments to the authors of those articles raises troubling questions about whether Medtronic crossed the line regarding off-label promotion of Infuse," the spokesman said.

Lou Bograd of the Center for Constitutional Litigation said the overwhelming off-label use of Infuse suggests that promotion is going on. Doctors are free to use medical devices any way they see fit, he acknowledged, but in this case more than eight in 10 uses are not FDA-approved.

"[It] defies credibility to say it's just doctors deciding to do this on their own," Bograd said. "Medtronic engaged in a false, misleading promotional campaign."

Bograd argued this point to Hennepin County District Judge Laurie Miller in May in what could become an influential case nationally.

Minneapolis lawyer Stuart Goldenberg, Bograd's co-counsel, represents clients in 35 Infuse cases in Minnesota who will be affected by ­Miller's decision. Goldenberg said he has "hundreds more" suits that might be filed.

In the Hennepin County case, Medtronic's lawyers denied off-label promotion of Infuse and argued that none of the 35 Minnesota plaintiffs has the right to sue.

"Many [cases] have already been dismissed based on the pre-emption doctrine established in Riegel," Medtronic said in its statement to the Star Tribune. "We have a number of defenses for these cases, including pre-emption, and will stand behind our product and vigorously defend it in court."

Conflicting opinions

Miller's decision is expected this summer. It will add to a handful of conflicting lower-court opinions that almost everyone believes will eventually end in a Supreme Court decision.

Prince also believes the issue "cries out for federal legislation."

"Off-label promotion is prohibited by federal law, but state law could also prohibit it," he said. In that case, a personal injury law suit might be allowed to go forward. But the courts have thus far "confused this by going off in all directions."

On June 18, a two-year, $2.5 million Medtronic-funded comprehensive re-analysis of all past Infuse research showed that the bone growth product did not perform as well and had more adverse effects than Medtronic-sponsored researchers had said.

The only use of Infuse that has received FDA approval is to implant it through the front of an adult's body to help recovery from lower-back spinal fusion surgery and then only if the bone growth factor is constrained in a specific brand of cage.

Otherwise, studies show that unwanted and potentially dangerous bone growth can occur and cancer risks may arise, said Dr. Eugene Carragee, editor of the Spine Journal. Carragee devoted the June 2011 issue to a scathing critique of the Infuse research that Medtronic sponsored.

Carragee said he took on Medtronic because its sponsored research results differed so markedly from research the company did not pay for and because of Medtronic's influence on the content of scholarly articles.

Still, that may not rise to the level of off-label promotion.

"Manufacturers can send representatives to medical conferences and say, 'Doctors A, B and C used the device in this way,' " said Prince. Doctors can also write about off-label device use in scholarly journals. "That's not considered promotion."

Ron Goldman could be the first lawyer in the country to actually get an Infuse off-label-promotion case before a jury. The Los Angeles attorney persuaded a judge there to let his client go to trial. The case is set for November, although Goldman expects a delay.

"Underlying all the legal mumbo jumbo," he said, "we have people who are severely injured."

Jim Spencer • 202-383-6123