Can Biomechanics Experts Opine On Medical Causation? Texas District Court Says No

    Biomechanics Expert

    Court: United States District Court for the Southern District of Texas, Houston Division
    Jurisdiction: Federal
    Case Name: Shaw v. United Airlines, Inc.
    Citation: 2018 U.S. Dist. LEXIS 155838

    This personal injury case involves a plaintiff who sustained injuries when she was struck by a passenger cart at the George Bush Intercontinental Airport in Houston, Texas. The defendants, United Airlines, Inc., and Air Serv Corporation retained a biomechanics expert with both educational degrees and plenty of career experience in biomechanics, injury consistency, and accident reconstruction. Pending before the court was the plaintiff’s motion to exclude the testimony of the defendants’ biomechanics experts on the basis that he was unqualified to opine on the issues at hand.

    Arguments For Exclusion of Defendants’ Biomechanics Expert

    The plaintiff argued that the defendant expert’s report offered conclusions regarding lack of bruising, the cause of her injuries, and the accelerated degeneration of her spine – all of which were related to medical causation. The plaintiff argued that because the expert was a professional engineer and not a medical doctor, he was not qualified to offer opinions regarding medical causation and such conclusions should be excluded. The plaintiff also argued that the entirety of the expert’s testimony was unreliable for three reasons: (1) the expert only inspected one cart, (2) the expert’s measurements were inadequate, (3) the expert’s findings were overly general and conclusory.

    The expert pointed to Layssard v. the United States, where the expert’s qualifications to provide testimony on medical causation were challenged and the court held that the expert was precluded from testifying as to medical causation and “limited his testimony to the forces involved in the collision and whether or not these would generally lead to injury.

    Furthermore, the defendants contended that this case was similar to McClure v. Greater San Antonio Transp. Co., No. SA-08-CA-112-FB, 2008 WL 11335001 (W.D. Tex. Oct. 3, 2008) in which the plaintiffs challenged a biomechanics expert’s qualifications “to render medical causation opinions.” The McClure court denied the challenge to exclude the expert’s testimony and held that the expert was qualified to testify on the biomechanics of the accident at issue.


    The court found the expert’s methodology sufficient to render his opinions reliable. The court reviewed the expert’s curriculum vitae and found that the expert was qualified to testify as a biomechanics expert, but not to any issues of medical causation. Further, the court reviewed the expert’s conclusions in his expert report and found that they were within his realm of expertise in biomechanics. The plaintiff was free to object at the time of testimony if the expert’s testimony addressed medical issues which he was not qualified to provide. With respect to the plaintiff’s other three arguments, the court found that all three contentions went to the weight of the evidence, not its admissibility and that the methodologies could be addressed on cross-examination.