Judgment was handed down on 21 May in the DePuy Pinnacle Metal on Metal Hip group litigation: Gee & Others v DePuy International Limited [2018] EWHC 1208 (QB)

312 claimants in the group litigation brought claims against DePuy, alleging that the hip prostheses with which they had been implanted were defective for the purposes of the Consumer Protection Act 1987 (the Act) and the Product Liability Directive 85/374/EC (the Directive). The judgement followed a trial at first instance of a common preliminary issue, namely "whether or not the defendant is liable to the claimant, subject to any development risk defence." The preliminary issue encompassed questions of causation.

All the claimants had been implanted with metal on metal (MoM) hip prostheses and claimed to have suffered an adverse reaction to metal wear debris generated by their implants, (ARMD), necessitating revision surgery. They claimed that the prosthetic hips were defective because:

  • The prostheses shed metal debris in the course of normal use, which caused some patients to suffer an adverse immunological reaction.
  • The prostheses carried an abnormal risk of failure during the first 10 years after implantation, compared to a comparator.

The claimants asserted that they had suffered personal injury caused by the defect and therefore that DePuy was liable to compensate them.

Andrews J held that the inherent propensity of all prosthetic hips to shed particulate debris through normal use, to which some patients may suffer an adverse immunological reaction, did not constitute a "defect" within the meaning of the Act and the Directive. The propensity did not become a "defect" by reason of the recorded incidence of such adverse reactions or the calculated risk of the probability of the revision of the prosthesis on account of them. Safety is inherently and necessarily a relative concept because no product can be absolutely safe. For a product to be defective, there must be an "abnormal risk" associated with use as compared with an appropriate comparator. The situation was therefore different from that considered by the CJEU in Boston Scientific, where the liability of the producer arose from the "abnormal potential for damage" which the affected products could cause to the person concerned.

Andrews J also found that the claimants had failed to establish that the MoM hip prostheses manufactured by DePuy did not meet the level of safety that the public generally was entitled to expect at the time they entered the market in 2002. The Court was unable to conclude, on the balance of probabilities that there was a materially greater risk of a DePuy prosthesis failing within the first 10 years after implant, than a comparator prosthesis and thus that the product carried with it an "abnormal risk" of damage.

The judgment considers in detail the factors to be considered and the approach to be taken when ascertaining whether or not a product is defective or not. The Court agreed both with the primacy of establishing defect and with the flexible approach to doing so described by Hickinbottom J in the earlier judgment of Wilkes v DePuy International Limited [2016] EWHC 3096 (QB). Relevant factors which may, in appropriate cases, be taken into account when considering the safety which persons generally are entitled to expect therefore include the benefits associated with use of the product, the ease and extent to which a risk can be eliminated or mitigated, the existence of a learned intermediary and the information provided to the intermediary, compliance with a regulatory regime. In order to prove the presence of defect, "a claimant must establish what it is about the state or behaviour of the product or the risk that it posed that led it to fall below the level of safety that persons generally were entitled to expect at the time the product entered the market".

The claimants' primary argument was that analysis of defect should start by identifying a harmful characteristic, or potential for damage in the product. The Court rejected this approach saying that it appeared "directly contrary to the spirit and objectives of the Directive and the Act, which require the Court to move away from the concept of a "defect" being some flaw or failing in the product, and to concentrate instead on whether in all the circumstances the product meets the requisite objectively assessed safety standard."

While a first instance decision, this extensive and thorough judgment is likely to prove important in the field of product liability. We will comment in more detail in future publications.

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