When we were small – ten or so – our father worked twenty miles from our home, in the town in which we now live.   The town was – and is – a few miles from the Devon Horse Show, a world-famous affair held for eleven days each spring spanning Memorial Day Weekend.  For one wondrous day of the show, back in those days, we were allowed to skip school.  Our father would drop us off at the show grounds on his way to work – maybe 8 a.m. – and would pick us up around 6 p.m.  We watched everything from tiny children in lead-line classes to Olympic equestrians in jumper stakes.  We never got enough – of the Devon fudge and iconic Devon tea sandwiches, of the overdressed matrons in box seats handed down across generations, and, especially, of the horses.  Oh, the horses.  Sometimes, words alone are enough.  We need only hear the words “Devon Horse Show” to be transported back to our wide-eyed childhood wonder and to chafe with anticipation of the next Devon outing.  Which, we delightedly add, is this weekend.

In the Rule 702-bound world of expert opinions, words are never enough.  To wit, an expert’s opinion carries no weight unless the expert arrived at the opinion through a reliable methodology.  Which, as you will see, the plaintiff’s expert in today’s case did not.  In Johnson v. Depuy Syntheses Prods., Inc., et al., 2022 U.S. Dist. LEXIS 89996 (W.D.N.C. May 19, 2022), the plaintiff suffered severe injuries, including a femur fracture, in a head-on collision between her motorcycle and a car.   The femur fracture was repaired with the defendant’s stainless steel compression plate.  Nine weeks after surgery, x-rays revealed that the broken femur was not healing – was not forming the “callus” a healing bone produces.  About five weeks later, the plaintiff rolled over in bed and felt a “pop” in her leg.  In surgery, the plaintiff’s doctor observed that the compression plate had fractured, and that there was “minimal to no callus at the fracture site.”  Johnson, 2022 U.S. Dist. LEXIS 89996 at *9,

The plaintiff filed suit in state court in North Carolina, and the defendant removed the case to the Western District of North Carolina.  North Carolina law does not recognize strict liability for defective products, so the plaintiff sued for breach of the implied warranty of merchantability.  This cause of action requires a plaintiff to prove that product was unfit for its ordinary purpose, which in turn requires proof that the plaintiff’s injury was due to “the defective nature of the goods.”  Id. at *10 (citation omitted).

Both sides agreed that “high-cycle reverse-bending fatigue” caused the plate to break.  Id. at *8.  The defendants contended that the fatigue resulted from the disunion of the unhealed femur bone, which put undue stress on the plate.  The plaintiff’s expert offered the contrary opinion that “irregular microstructure” of the steel plate, resulting from a manufacturing defect, “most likely contributed to the premature failure” of the plate. The defendant moved to exclude the expert’s opinion, arguing that the opinion was unreliable.  And the court agreed.  The court explained that, while the expert offered the opinion that the plate’s microstructural irregularities constituted a manufacturing defect, he failed “to explain how the plate’s alleged microstructural inconsistency ha[d] any relevance to the question of whether the device was unfit for its ordinary purposes.”  Id. at *10-11.  Specifically, he failed “to articulate any standard of microstructural consistency to which internal fixation devices must adhere in order to sustain the forces placed upon them during ordinary use.  Relying on Sardis v. Overhead Door Co., 10 F.4th 268, 289 (4th Cir. 2021), about which we blogged here, the court held that the opinion was inadmissible ipse dixit because the expert could not “articulate the testing standard to which . . . the defendant was required to adhere.”  Id. at *11.   The court elaborated,

[The expert] does not address what stresses such a plate would have to endure; the length of time the plate’s integrity would have to be maintained until expected bone union; or whether the weight or other physical characteristics of the patient would affect the expected stresses. Moreover, he did not address the degree to which any microstructural inconsistency in the plate would cause it to fail under such expected stress, while a more consistent structure would not.

Id. at *11. The court concluded:

Without evidence of such a standard, a jury would not be able to ascertain whether the plate’s alleged microstructural inconsistency bears any relationship to whether the device was unfit for its ordinary purposes and thus was defective. . . . [The expert’s] conclusory opinion that the irregularity in the plate constituted a manufacturing defect is irrelevant and unreliable, and must be excluded.

And there was more.  The court went on to comment that, even if the expert’s “manufacturing defect” opinion were admissible, he had not presented “any admissible evidence that this defect was a proximate cause of the plate’s failure and thus of the Plaintiff’s injury.” Although the expert offered the opinion that the supposed defect “likely contributed” to the development of the fatigue cracks in the femur plate, he did not “actually opine that this irregularity contributed to the ultimate failure of the plate.”  Id. at *12-13 (emphasis in original).  In other words, the expert did “not state any causation opinion to a reasonable degree of scientific certainty.”   Id. at *13.

There also was no indication that the expert conducted any testing in formulating his opinion. Even the expert conceded that “additional destructive analysis [was] necessary to determine the extent [to which the alleged] manufacturing defect contributed to the failure.” Without such testing, as the court emphasized, the expert’s opinion was “merely a hypothesis – not scientific knowledge within the meaning of Rule 702.”  Id. at *13-14 (citations omitted).   

Finally, the court pointed out that the “hypothetical nature of [the expert’s] causation opinion was further evidenced by his failure to rule out (or even consider) potential alternative causes for the plate fracturing” – a “fatal omission.”  Id. at *15.  And so the court excluded the expert’s opinion, leaving the plaintiff without admissible evidence of a “defect” in the plate.  Without such evidence, the plaintiff could not satisfy this element of her “breach of implied warranty claim,” and the defendant was entitled to summary judgment as a matter of North Carolina law.

We like this opinion.   Seems like an easy answer to us, but we have been on the wrong side of courts getting it wrong on similar facts.  We wish all of you a safe Memorial Day weekend.