Dr Hilary Jones explained on Daybreak how Mark Cahill's hand transplant was a world first.
He said hand transplants have been done since the 1960s, however this is the first time that the hand has been removed and the donor organ has been transplanted on at the same time.
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Downpours keeping us on our toes today
The M20 in Kent has been closed in both directions after a pedestrian bridge allegedly collapsed on the motorway on Saturday.
The AA have warned of traffic jams and urged people to carry extra water in their vehicles because of the warm weather.