Specialists in the United States have told the former champion jockey that he must not ride again until he has regained the full strength in the right arm that has been giving him problems since a fall at Fontwell in May last year.
Dunwoody, 35, who became jump racing's most successful rider when he passed Peter Scudamore's record of 1,678 on Easter Monday, said: "I really miss racing and I enjoy riding now as much as I've ever done.
"But I've had pains in the shoulder when I've had a bad fall and that's been damaging the nerves which feed the muscles in the arm. My biceps are wasted and another muscle in the forearm is also wasted."
The high-class chaser Escartefigue has left David Nicholson's yard and has joined Paul Nicholls. The seven-year-old, a leading novice in the 1997-98 season when he won four times including the Martell Cup at Aintree, has failed to score since but was second to Teeton Mill in the King George VI Chase on Boxing Day.
"It's very nice to have a horse of his calibre join the yard as he's top class," Nicholls said. "David Nicholson did well with him and I'm hoping a change of scenery will do him good just like it did for Green Green Desert here last season."Reuse content