Car headrests at the wrong height are costing Britain more than £2bn a year in whiplash injuries, says the RAC Foundation.

Painful neck injuries from road accidents are caused when headrests fail to protect the neck, the organisation said.

Its national survey, carried out in March among 500 motorists, found that 55 per cent of head restraints were at the wrong position and would not protect the neck in the event of a crash.

The top of a headrest should be level with the top of the head, or no lower than eye level.

Thousands of people suffer whiplash injuries in the UK each year and the European federation of motoring organisations - the FIA - has estimated that up to 80 per cent of all rear impact injuries in Europe ends with at least one occupant suffering from neck or spinal injuries.

The RAC Foundation is calling for the introduction of active head restraints designed to automatically shorten the gap between the head and the restraint in a collision, giving improved protection from whiplash.