The warning comes after a landmark High Court ruling. Teenager Sam Harris won compensation, which is likely to exceed £1m, for suffering a serious and traumatic brain injury while using a bouncy castle.

Sam, 11 at the time of the accident, was jumping on a bouncy castle which had been hired by Catherine and Timothy Perry for their triplets' 10th birthday party. Unfortunately, a much older, larger boy got on the castle and while attempting a somersault, he accidentally kicked Sam in the head causing him a fractured skull and long-term injury which will leave him needing care for the rest of his life.

The High Court awarded Sam compensation on the basis that the Perrys should have supervised the use of the bouncy castle more closely and prevented older children using it with younger ones.

Andrew Welch, a partner specialising in personal injury at Wigan law firm, Stephensons Solicitors, said: "This is a tragic case for a boy who is now going to be disabled for the rest of his life.

"Fortunately the Perrys who hired the bouncy castle were covered by insurance and therefore it is their insurers who will be paying the compensation.

"There are between 2,500 and 3,000 bouncy castle-related injuries each year, some of them very serious, so this case simply underlines that people should take common sense precautions when hiring or using a bouncy castle and make sure they are insured.

"Parents should make sure there is proper supervision when it is being used by children.

"If people are sensible, there is no reason why children and others should not carry on enjoying bouncy castles at birthdays and similar events."