Nicky Henderson say scans have revealed Constitution Hill is suffering from bruising in a pastern.
The brilliant hurdler was reported to be lame on Friday with an intended reappearance in next week's Bet MGM Fighting Fifth Hurdle shelved.
Speaking to ITV Racing on Saturday the trainer said: “He had a long day yesterday, starting with x-rays which showed nothing which you have to be pleased about. You do wonder if there might he a chip or something in a knee or fetlock, but there was nothing to see anywhere.
“He had an ultrasound then a MRI and the MRI scan has revealed there’s a bit of bruising in the pastern. There was a tiny little mark in there and it appears on the MRI that it’s touching a nerve. No part of the mechanism is injured at all, there’s no damage to anything, no tendons or ligaments are affected, nothing is fractured but he is still lame.
“He was remarkably better by Friday evening but it is touching a nerve. I don’t know much about these things. Dave Matterson, our vet who has been treating him, says he's never seen it in 40 years practising as a vet.
“The obvious question for them was how long is this going to take? Dave’s opinion to me this morning was to say there’s a maximum and a minimum. Maximum he said was three weeks which would not get us to Kempton for the Christmas Hurdle. The minimum might be three days but there’s nothing you can do, you can’t hurry it up.”
Will Sir Gino head to Newcastle?
Constitution Hill’s absence for the Fighting Fifth could leave the door open for stablemate Sir Gino, who is now set to do a piece of work with the race in mind.
“I think we’ll do a bit of work with him tomorrow, we’ll see what the weather’s like,” Henderson said of the horse. If it’s not absolutely foul, which it could be, then I’d probably try and work him tomorrow or Monday and see where we go from there with a definite view that we would, if all goes well, go to Newcastle.”
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