A design defect is a problem which occurs during the design process. If the defect causes injury, or exacerbates an existing injury or illness, the patient will likely have the basis of a product liability lawsuit.

   To determine whether the medical device design defect directly caused a patient’s harm, the courts rely on two rules. They are the “consumer expectations rule” and the “risk-utility balancing rule.”

   Under these rules an actionable design defect exists when the medical device is:

•Unreasonably dangerous as designed, or

•Not safe for its intended and reasonably foreseeable uses.

   An alternative approach to design defect is called the consumer expectation test. Under this test, a manufacturer may be liable if a product fails to perform as safely as an ordinary consumer would expect when used in a reasonably foreseeable manner.

   However, in many cases, the questions of how a device should function and what design would make it safe are ones that most people are not in a position to answer. So, the consumer expectation test has been limited to cases in which the design defect is obvious and apparent to most average users.

   A product is “unreasonably dangerous” because of its design if the product fails to perform as safely as an ordinary consumer would expect when used as intended or when used in a manner reasonably foreseeable by the manufacturer and/or the risk of danger in the design outweighs the benefits.

   Sometimes products, however, are simply unavoidably unsafe. These are cases in which the products are unsafe even if used exactly as intended. There are no reasonable alternative designs which would make the product safe.

   Factors relevant to this decision include:

•the usefulness of the product,

•how efficiently safety mechanisms can be built into the product,

•the availability of safer products that achieve similar goals,

•the possibility of decreasing the danger during the manufacturing process and

•the awareness of the standard user of the danger.

   If the product is properly prepared and accompanied by proper directions and warnings, it may not be considered defective.