An operation in one of the cheaper destinations, such as the popular Apollo hospital in New Delhi, India, could be a fraction of the cost of the equivalent private treatment in the UK, even with flights and accommodation.

A knee replacement in Britain might cost £14,000 compared with about £6,000 in Poland, while a spinal fusion operation to ease acute back pain might cost £18,000 in Britain compared with £5,500 in India, including travel.