Last year, the MDL Panel denied an attempt to centralize all of the federal “shoulder pain pump – chondrolysis” cases. See In re Shoulder Pain Pump – Chondrolysis Products Liability Litigation, MDL No. 1966 (JPML Aug. 11, 2008) (link here). So the cases have moved ahead individually in federal courts across America.

A couple of weeks ago, a defendant got good news in one of those cases. In Kilpatrick v. Breg, Inc., No. 08-10052-CIV-MOORE/SIMONTON, slip op. (S.D. Fla. June 25, 2009) (link here, courtesy of the Products Liability Prof Blog), Judge K. Michael Moore found that plaintiff’s proffered proof of general causation linking a pain pump to chondrolysis didn’t satisfy Daubert, which doomed the plaintiff’s case.

Kilpatrick operated a charter fishing guide service in the Florida Keys. He underwent arthroscopic shoulder surgery to repair the ring of tissue surrounding the shoulder socket. To control post-operative pain, the surgeon implanted a shoulder pain pump manufactured by Breg.

A couple of years later, Kilpatrick’s shoulder started to hurt again. His physician diagnosed him with glenohumeral chondrolysis — a breakdown of the cartilage in Kilpatrick’s shoulder joint. Kilpatrick ultimately had to undergo a total shoulder replacement.

Kilpatrick filed the customary complaint — a few product liability counts, negligence, and alleged violation of the Florida Deceptive and Unfair Trade Practices Act. Breg filed a motion for summary judgment on the ground that Kilpatrick didn’t demonstrate that its pain pump could cause the type of injury Kilpatrick suffered.

Judge Moore agreed.

Kilpatrick seems to have hired a real doctor as an expert witness: Gary Poehling, M.D., a long-time orthopedic surgeon and professor of orthopedics who had served as editor-in-chief of a leading orthopedics journal. But there wasn’t any science to back up Dr. Poehling’s opinion that a pain pump could cause chondrolysis.

Poehling relied on four published articles to support his general causation opinion.

The Hansen study examined 152 patients who underwent 177 shoulder surgeries. Only 19 shoulders in 17 patients “had bupivacaine-dispensing pain pumps inserted in them.” Slip op. at 9. “Of those, twelve shoulders in ten patients developed chondrolysis.” Id. The Hansen study, however, included no statistical analysis and thus didn’t demonstrate statistical significance or whether it was “statistically meaningful to extrapolate from the relatively small sample size.” Id. Additionally, the study acknowledged that “[t]hermal and/or radiofrequency, suture material, and reabsorbable suture anchors may have played a role not yet completely understood” in causing the chondrolysis. Id. And neither the Hansen study nor Dr. Poehling could explain “why nearly 40% of patients treated with pain pumps did not develop chondrolysis,” id., leaving “an unexplained 40% error rate in Poehling’s hypothesis.” Id.

So much for the first, and strongest, of the four studies that Poehling relied upon.

The Gomoll study was a controlled study of rabbits. The court noted the many difficulties in animal studies and rejected the Gomoll study as proof of general causaion in humans. Id. at 11.

The Greis report, a case study of two female swimmers, recognized on its face that “the exact cause of the chondrolysis remains unknown.” Id. at 12. Moreover, “anecdotal reports of two individuals are, of course, not statistically significant evidence of causation.” Id.

And Dr. Poehling’s own 228-word editorial said nothing about general causation and in fact acknowledged that “‘idiopathic’ chondrolysis — that is, chondrolysis caused by unknown factors — has also been described in the medical literature.” Id. at 12-13.

Absent scientific evidence of general causaion, the court could have stopped there.

But it didn’t.

It went on to note that Poehling said nothing about the background risk of chondrolysis and conceded that the scientific literature has not reached a conclusion about the cause of chondrolysis. Id. at 13-15. Finally, Dr. Poehling’s differential diagnosis, ruling out other causes of Kilpatrick’s chondrolysis, could not overcome the absence of evidence proving that the pain pump could have been the cause. Id. at 16.

There was thus no evidence linking the pain pump to Kilpatrick’s injury, and all of his causes of action failed.

Perhaps “pain pumps” will prove to be another example of a mass tort that wasn’t.