MINNEAPOLIS (AP) — The University of Minnesota Medical School has sent a cautionary letter to one of its top spinal surgeons for violating conflict-of-interest disclosure requirements arising from his work for Medtronic Inc.

The review found that Dr. David Polly did not disclose payments he received from the Fridley-based medical device maker in two published journal articles and on one research poster. But the university letter did not recommend any disciplinary action and said he had otherwise “demonstrated substantial compliance” with university conflict-of-interest and disclosure rules.

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Polly, who earned more than $1 million in consulting fees from Medtronic between 2003 and 2007, said Monday he agreed with the findings.

“I thought I was doing as good a job as could be done on the disclosure and complying with the university policies,” Polly said. “I came up short in two or three instances where my ‘I’s’ weren’t perfectly dotted or ‘T’s’ crossed. I acknowledge that and completely accept the responsibility that goes with it.”

However, he said, the disclosure rules have changed dramatically since 2006, and they differ so much from publication to publication that it’s difficult to know how to comply.

“Even when you are trying very hard to do the disclosure, it’s hard to get everything just right for a variety of reasons,” he said.

The review was launched two years ago after U.S. Sen. Charles Grassley, R-Iowa, criticized the surgeon for failing to report his Medtronic payments to members of a Senate committee in 2006. At the time, Polly was requesting congressional funding for research that would have benefited Medtronic.

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The university sent a letter to Grassley at the time saying Polly had properly disclosed any conflicts of interest according to the school’s policy at the time, but promised to review the situation further. The new review eventually turned up three violations of university policy.

The violations involved a research poster submitted to the Society of Military Orthopaedic Surgeons for a conference in December 2008, a paper he wrote in 2007 for the Journal of Orthopaedic Trauma and a study in the journal Spine.

As a result of the investigations, Polly said he stopped doing consulting work for Medtronic so that he would be free to continue his research at the university. He estimated he has spent close to a quarter of a million dollars defending himself.

Polly said he understands why the government and public want to know about the financial details of physician contracts with industry. But he said this kind of scrutiny could have a chilling effect on cutting-edge research.

“In the surgical fields the only way that advancements are made is the collaboration between industry and physicians,” Polly said. “And I don’t think we want to stifle that.”

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