Ruling offers greater clarity on steps manufacturers can take to defeat any claims their products are defective, says expert

The judgment emphasises the need for manufacturers to maintain good records on safety testing, follow any regulatory procedures they are bound by, and regularly review and update product information to ensure potential risks or side-effects from the product's use are clearly flagged. It also highlights the benefits of developing products that conform to industry technical standards.

The December ruling, by Mr Justice Hickinbottom, concerned a claim for damages brought by a patient against a medical device manufacturer.

Anthony Wilkes had an artificial left hip inserted in a hospital operation in January 2007. The device was manufactured by DePuy International.

In January 2010 the device fractured. It was subsequently replaced with a newer model, but a new fracture was identified in that device in 2015. According to the ruling, there was some evidence that "metal debris" had been found around Wilkes' hip joint following the fracturing of the device.

Wilkes sued DePuy for negligence and claimed the company had also breached UK consumer protection laws. On the latter issue, Wilkes said a component of the device DePuy manufactured contained a defect and raised a claim for damages against the company.

Under the Consumer Protection Act 1987, which the claim was brought under, a product is deemed as defective if its safety is "not such as persons generally are entitled to expect", taking into account "all the circumstances".

To-date there has been little case law clarifying what proof needs to be presented to demonstrate that a product is defective. A 2001 case between 114 patients and the National Blood Authority (NBA) has, until now, been seen as the leading authority on the matter. The ruling in that case stressed the importance of identifying 'the harmful characteristic which caused the injury' and determining whether the product performed as the producer intended or was other 'non-standard', and that other factors could have a bearing on the definition of 'defect'.

Mr Justice Hickinbottom, however, largely dismissed the approach set out in the NBA case and instead outlined other factors which he considered relevant.

While the judge stressed that there is no one-size-fits-all approach to determining defectiveness of every product that is manufactured, his ruling offers useful guidance on steps manufacturers can take to safeguard themselves against such claims.

One of the factors that Mr Justice Hickinbottom considered relevant in this case was the application of regulatory standards and Depuy's conformity to those standards, specifically the UK's Medical Devices Regulations and the EU's Medical Devices Directive, from which the UK rules are derived.

The judge made it clear that manufacturers that abide by their regulatory requirements, and/or who adhere to industry technical safety standards, do not have an absolute defence to claims that their products are defective.

However, he said it "may be challenging for a claimant to prove that the level of safety that persons generally are entitled to expect is at a higher level" than those which are set out in regulation. This is particularly so where "every aspect of the product's design, manufacture and marketing has been the subject of the substantial scrutiny, by a regulatory body comprised of individuals selected for their experience and expertise in the product including its safety, on the basis of full information, and that body has assessed that the level of safety is acceptable", the judge said.

He said that the award of a Europe-wide 'CE' marking, certifying that a medical device meets safety and other standards, "may be evidence (and, in an appropriate case, powerful evidence) that the level of safety of the product was that which persons generally were entitled to expect".

Specifically on the component of the DePuy device that fractured, Mr Justice Hickinbottom said it "satisfied all of the regulatory requirements, including those imposed to ensure that the product was 'acceptably' safe" and that it had also been "tested to a higher level than the fatigue failure standard".

The judge had earlier stated that "no medicinal product is free from risk" and that the 'safety' of those products is a "relative concept" based on a risk-benefit assessment.

Mr Justice Hickinbottom also referred to disclosures made by DePuy about the potential risks that could arise through use of its device.

The judge pointed out that while some manufacturers of medicinal products are required to provide certain information on their product directly to patients, no direct-to-patient disclosure obligation applies in the case of "prosthetic components", since they are only available through medical professionals.

However, manufacturers of those devices must provide 'instructions for use' (IFU), containing relevant information, such as appropriate warnings, to those professionals. The judge explained it is then incumbent on those professionals to help the patient make an informed decision about treatment.

Mr Justice Hickinbottom said "warnings given in relation to a product will qualify the expectation that the public generally are entitled to expect of a particular product, and thus go to the issue of whether that product is defective".

The judge said, though, that in cases where a "learned intermediary", such as a medical professional, acts as the facilitator of information about a medical device, the situation is more complicated. The mere fact disclosure of risks takes place through an intermediary "does not provide a complete or automatic defence for a producer of a medicinal product", he said.

In the case of DePuy's risk warnings, the judge said that the company had "expressly warned" in its IFU of the risk that its device component could fracture in the way it did in Wilkes' case. However, he said this risk was not conveyed to Wilkes, although "other, much higher, risks of failure of the hip replacement" were explained to him.

Mr Justice Hickinbottom said the component's failure was "unfortunate". He said that while he had sympathy for Wilkes, it had not been proven that the DePuy device component suffered from a defect at the time it was put onto the market.

The judge's comments should prompt medical device manufacturers to review their safety testing practices, regulatory compliance procedures and record keeping more generally. They should also regularly review the disclosure documents they issue for their products to ensure they mark clearly all the risks or potential side-effects associated with the use of their products.

Manufacturers that take these steps, document their actions and adhere to industry standards will be best placed to overcome any challenge brought against them that their products are defective.

Manoj Vaghela is a product liability expert at Pinsent Masons, the law firm behind Out-Law.com.