By Tim Masters
Entertainment reporter, BBC News
David Tennant is due to start filming the first of four specials in January
David Tennant is expected to be fit enough to start filming scenes for a Doctor Who special next month, just weeks after surgery on his back.
The show's executive producer, Russell T Davies, said he was "hopeful" Tennant would start filming on 19 January.
"We'll have to be very careful," he said. "I don't think we'll be swinging him on a wire on his first day back."
The actor's back injury has forced him out of a London stage production of Hamlet until after Christmas.
Davies, who was speaking at the press launch of BBC One's Christmas Doctor Who special, The Next Doctor, said there would be no re-writes on the next story to cut down on Tennant's action scenes.
"No, there's been none of that, and I think David would have told us by now because he's read the first script."
He said the production was insured in case Tennant was still recuperating when filming resumed.
Tennant is joined by Velile Tshabalala and David Morrissey in the Christmas story
Neither Tennant nor David Morrissey - who plays "The Next Doctor" - attended the launch.
The Christmas story sees them team up to battle a threat from the Cybermen in London on a snowy Christmas Eve in 1851.
The episode also stars Dervla Kirwan, who plays evil workhouse matron Miss Hartigan.
Warning - potential spoilers ahead: Please do not read any further if you do not wish to know more about The Next Doctor or next year's specials
The story introduces some new variations on the Cybermen: the dog-like Cybershades and the CyberKing.
It also features a mystery surrounding a man named Jackson Lake, the Doctor taking a trip in the other Doctor's Tardis and a new kind of sonic screwdriver.
Dervla Kirwan wants to start the "new Industrial Revolution"
Davies revealed that the first of next year's Doctor Who specials will be filmed abroad.
"It's going to be quite exotic," he said. "I can't tell you where, but we've got four days filming abroad, to give it a bit of size and a new feel to it."
He added there was also a "great guest star".
Tennant announced in October that he would stand down as the Doctor after filming the four special episodes in 2009.
Davies said each special would feature a different companion and that he would write Tennant's two final stories which would be broadcast "toward the end of next year".
"The big climax is mine, all mine," he said.
He added that the production team for the 2010 series of Doctor Who were "auditioning or looking" for a new Doctor.
"I think it could be a while - it's a very big deal to set up. Whoever becomes the Doctor has got to take on a whole life. It's not just becoming a part of a TV show," he said.