'His wife helped him': Michael Schumacher signs helmet to raise money for Jackie Stewart charity

Formula 1 champion Jackie Stewart wore a helmet bearing the signature of all living F1 champions, including Michael Schumacher, as he drove one of his title-winning cars for charity ahead of the Bahrain Grand Prix.

Seven-time champion Schumacher has not appeared in public since he sustained severe head injuries in a 2013 skiing accident. Few details of his condition have been made public.

Stewart earlier told the Daily Mail newspaper that Schumacher had signed the helmet with help from his wife Corinna.

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“It is wonderful that Michael could sign the helmet in this worthy cause — a disease for which there is no cure,” Stewart said.

“His wife helped him, and it completed the set of every single champion still with us.”

The 85-year-old Stewart, a three-time F1 champion, was driving his 1973 championship-winning Tyrrell car to raise awareness for the Race Against Dementia charity, which he founded to research treatments for the disease. Stewart is caring for his wife Helen, who has dementia.

“To find a cure for dementia is my biggest wish,” he told the BBC this month. He said that Helen required specialist care and had recently been unable to recognise him.

"Just the other day it was time for dinner, she's getting up and I'm sitting close by, and she says, 'Where's Jackie?' That's the first time that's happened and that's only a few weeks ago," he said.

"A bad feeling came over me."

The helmet, now signed by every living F1 world champion, will be auctioned to fund a groundbreaking new blood test developed by Cambridge University.

It is hoped the test could detect early signs of dementia before symptoms appear.