Is a product defective because it did not perform as hoped?  How about if it failed or even if it broke?  Of course not, and this is doubly true for implanted medical devices because all treatment with medical devices carries risk, including the risk of poor outcomes.  You therefore can’t say an implanted medical device was defective just because the patient’s post-operative course did not go well, even if an expert attempts to say so.  Take for example the spinal plate at issue in Harris v. Stryker Spine, No. 3:12-cv-874, 2014 U.S. Dist. LEXIS 118897 (S.D. Miss. June 23, 2014).  The plaintiff in Harris was in an automobile accident in which he was thrown from the car and suffered severe spine injuries.  Id. at *2.  A neurosurgeon therefore removed damaged bone from his spine and replaced it with a graft, which required the use of plates and screws for temporary support.  Id. at **2-3

Alas, the graft did not take.  The graft material fractured, the screws holding the plate backed out, and the bones in the plaintiff’s spine failed to fuse—resulting in another, more complicated spine fusion procedure.  Id. at **3-4. 

So why the lawsuit?  Well, a radiologist interpreting a CT scan noted a “fractured intervertebral device.”  Id.  We don’t know if the radiologist was necessarily referring to the plate, and the explanted plate was discarded, so no one could look at it.  But that radiologist’s reference was enough for this plaintiff to sue the plate’s manufacturer, making numerous claims, but eventually abandoning all except manufacturing defect and a failure to warn. Id. at **4-5. 

The problem for the plaintiff is that there was no evidence that the plate suffered from a manufacturing defect or that the manufacturer failed to warn of a material risk.  The plaintiff did produce an expert, who opined that the product was defectively manufactured because “the device failure that occurred . . . would not normally occur unless the device was defective.”  Id. at *14. 

In other words, because the device allegedly broke in some way, it had to be defective.  Hmm.  That’s the kind of ipso facto reasoning that we condemned at the outset, and it’s lame – as we have discussed in more detail here.  The defendant plate manufacturer thought so too, and it rightfully challenged the opinion and moved for summary judgment.

The district court granted the motion and first questioned whether the plaintiff’s expert was qualified.  He was a neurosurgeon, but he had no training or education in metallurgy, material sciences, or bioengineering.  He also had not reviewed any materials about the product’s manufacturing and was not familiar with the manufacturing process.  Id. at **10-11.  The defendant thought he had no business giving opinions on a purported manufacturing defect, and the court thought that position “likely” was correct.  Id.at *12. 

In the end, the expert’s lack of qualifications did not matter, because the court excluded his opinions as unreliable regardless. The expert’s opinion was that the device was defective because it “failed by breaking,” but he could not explain what that meant, other than to say that “it didn’t do what it was supposed to do. . . . [i]t didn’t hold up.”  Id. at *14.  That is just another way of saying that it was defective because it failed, which does not fly.  The expert also stated that the device failure that occurred “would not normally occur unless the device was defective.”  Id. at *15.  But the court found that to be “not at all accurate” because the expert acknowledged at his deposition that there are many reasons unrelated to a product defect that can cause such devices to fail. Id. at *15. 

Lacking any basis for a valid opinion, plaintiff and his expert attempted to fall back on that most-abused method for determining medical causation—the differential diagnosis.  We have never understood how a diagnostic tool is at all useful in litigation to determine causation, but numerous courts have allowed plaintiffs and their experts to do just that.  But this expert’s differential diagnosis was no more reliable than any other part of his opinion. The district court started with this proposition:  “Where an expert employs differential diagnosis to ‘rule out’ other potential causes for the injury at issue, he must also ‘rule in’ the suspected cause, and do so using ‘scientifically valid’ methodology.”  Id. at *17 (citations omitted). 

This expert failed coming and going.  He “arguably” ruled out some possible alternative causes, but he also acknowledged a number of other potential causes that he did not rule out.  Id. at **18-19.  More fundamentally, the expert failed to “rule in” a manufacturing defect as the cause of the plaintiff’s injury.  He posited that the device “must have been defective since it failed,” but he could not say how it was defective or how it failed.  He could not even say what the radiologist meant when he wrote “fractured,” and because no one ever asked the radiologist, we may never know.  It takes a lot more than this to support a case in federal court, and it makes us wonder why this plaintiff ever bothered to try if this was the best he could do. 

The district court excluded the opinion and granted summary judgment.  The plaintiff made a last ditch argument that he did not need an expert to prove causation because the product’s labeling itself stated that “[p]ostoperative fracture of bone graft . . . can occur due to trauma, the presence of defects, or poor bone stock.” Aha!  The defendant admitted in its own labeling that “defects” can cause failure.  The court, however, brushed this argument aside with the observation that “it is plainly unreasonable to interpret this phrase as referring to a defect in the defendant’s own hardware.” Id. at *25.  In any event, the plaintiff still bears the burden of proving that the device deviated in a material way from the manufacturer’s specifications—i.e., that it suffered from a manufacturing defect—and the plaintiff could not sustain that burden “based on nothing more than a negative inference from (at best) ambiguous language in a warning.”  Id. at *26. 

Finally, the plaintiff had a failure-to-warn claim too, but the court found it “manifest that there is no warning that plaintiff reasonably claims should have been given which was not given or of which [his neurosurgeon] was not aware.”  Id.  The result therefore was complete summary judgment.  We have seen experts make chicken salad out of chicken feathers, but here there was nothing to work with.  This judge also was not fooled by a “differential diagnosis” that followed no reliable scientific methodology and thus “ruled in” nothing.