While the laws applicable to defective product cases varies from state to state, there are three legal theories common to all jurisdictions which may form the basis of a successful product liability case:
Manufacturing defect. In such cases the injury was caused as a result of defect in the manufacture of the product. An example would be a bicycle which was built with a small crack in the frame, which breaks when used, causing an injury to the rider.
Design defect. In these cases the injury was caused by a poor design (even though there may be no defect in the individual product itself). An common example would be a piece of industrial machinery which was built without a proper safety or protection devices, and as a result a worker is injured as result while using the machine.
Failure to warn, or "inadequate warning". These cases refer to injuries caused as a result of a product known to be potentially dangerous which was sold without a proper warning to the consumer. An example would be an over the counter drug sold without a warning of the hazards of use with certain other drugs, or excessive consumption, or possible side effects from its use.
If you or a family member has been injured because of what you believe is a product defect, you should consult an attorney familiar with product liability / defective product cases at the earliest opportunity to protect you right of recovery.