George Baker is reported to be facing "a long rehabilitation process" after suffering some bleeding in the brain following his fall in St Moritz last Sunday.
The jockey, who won the St Leger last September on Harbour Law, was riding Boomerang Bob for Jamie Osborne on the frozen lake track when the horse was brought down and fatally injured in the first race of the day.
Two other horses came down in the incident but neither they nor their jockeys were seriously injured.
Baker was airlifted to a trauma hospital in Chur and has remained in intensive care all week, undergoing a MRI scan on Friday which revealed the bleeding in his brain.
A statement issued by the Professional Jockeys Association said: "Following a fall during the first race at St Moritz on Sunday, February 26, George Baker was transferred by air ambulance to Graubunden Hospital in Chur, Switzerland, where he has remained in a stable condition in intensive care.
"Having had CT scans earlier in the week, George underwent a MRI scan today.
"Following those MRI scan results, George has suffered from some bleeding in the brain and we are anticipating a long rehabilitation process, but are hopeful that he will make a positive recovery.
"George will remain in hospital in Switzerland whilst arrangements are made for his return home to commence his rehabilitation.
"George's family would like to express their thanks for all the kind messages of support and would appreciate privacy at this difficult time."
Injured Coney Island ruled out of Cheltenham Festival by Eddie Harty
Coney Island has become the latest in a long line of high-profile horses to be ruled out of the Cheltenham Festival when it was revealed he had suffered a setback.
Eddie Harty's promising six-year-old has been sidelined with a badly bruised foot that has cost him his place at Prestbury Park, where he would have gone with strong claims following his victory in the Grade One Drinmore Novice Chase and a creditable second place in the Neville Hotels Novice Chase on his latest start.
"He's got a foot injury and won't recover in time for Cheltenham," said Frank Berry, racing manager to owner JP McManus.
"He's got a badly bruised foot. It's just come at the wrong time."
Coney Island was second favourite at around 6-1 for the RSA Chase and a top-priced 10-1 chance for the JLT Novices' Chase.
Le Breuil enters Festival equation for Ben Pauling following Newbury victory
Le Breuil could be a late addition to trainer Ben Pauling's Cheltenham Festival team after running out a convincing winner of the RR Elite "National Hunt" Novices Hurdle at Newbury.
Although not seen out since making a winning debut over hurdles at Sedgefield last November, the five-year-old, who holds entries in both the Neptune and Albert Bartlett, proved too strong for Benatar when claiming the extended two-and-a-half-mile contest by nine lengths.
Following the race, the winner was cut from 33-1 to 20-1 by BetVictor for both his Festival options.
Pauling said: "I've just about talked this horse up to everyone. It is a good step back on the ladder.
"Nico (de Boinville, jockey) said he had a good blow after the last. All in all it was a fantastic performance. His jumping is just electric. He is fast and accurate and hopefully he has a big future.
"The reason I left him in at Cheltenham was just in case he came out of this like a bull in a china shop. I'm pleased I left him in as it gives us options. If we don't go to Cheltenham, we will look at Aintree."
Michael Scudamore faces an anxious wait to see if Dinsdale (6-1) makes the cut for the Fred Winter after he opened his account in the Pheasant Inn Juvenile Hurdle.
The four-year-old picked up a 5lb penalty to increase his chances of getting into the Grade Three contest later this month after getting the better of favourite Most Celebrated by a length and a quarter in the two-mile prize.
Scudamore said: "They are going really well. That is the 21st winner of the season which is by far our best. Things could not have gone any better over the last week, from this time last week winning the Devon National to this chap winning.
"I thought turning into the straight he would find it a bit tough but fair play to the horse, he is really tough and stuck his head out well in the end.
"He is entered in the Fred Winter and the plan was if he ran well today, then try squeeze into that. If he is able to creep in, then that's the target."
A step up to Grade One company at Aintree next month could now be on the cards for Debece (5-2 favourite) after he demolished his rivals in the Physicool Handicap Hurdle.
After finishing third on his last two starts, the Tim Vaughan-trained runner turned the two-and-a-half-mile contest into a procession when coming home by an eased-down 19 lengths.
Vaughan said: "We went for it at Cheltenham and Aintree off a lower mark but he was a bit inexperienced.
"I said to Alan (Johns, jockey) to grab it by the scruff of the neck and get on with it as we wanted to win this. This is a proper horse. The plan was to go to Aintree after this and he needed to go up in the weights to get there.
"We have a choice of the three-mile handicap or running off level weights in the Sefton.
"He is a half brother to Don Poli and he is crying out for three miles and fences, but I just wanted to nurse him and I didn't want to run him on sticky winter ground."
Regal Encore team mulling Midlands National prep ahead of Aintree aim
Regal Encore could head to Uttoxeter in a fortnight's time ahead of a potential bid for glory in the Randox Health Grand National.
Anthony Honeyball's nine-year-old bounced back from disappointing efforts to win a valuable prize at Ascot in December, but was pulled up at Cheltenham the following month.
He is entered in the Ultima Handicap Chase at the Cheltenham Festival, but connections have pencilled in the Midlands Grand National on March 18 as his potential warm-up race for the world's most famous steeplechase in April.
Honeyball said: "Regal Encore is coming along well and could possibly run in the Midlands Grand National. But if it came up too testing there, he could go straight to Aintree or the Irish Grand National.
"He has got a good racing weight for Aintree (10st 12lb), whereas in the Midlands he would be one of the top weights. Running in the Midlands isn't the obvious Aintree route, but that's what we are thinking at the moment.
"He has been pretty unlucky here and there, and is a very genuine horse. He has blown a bit hot and cold but not in a temperamental way.
"He has put on some really good displays and then hasn't had the luck on other occasions, which has put a few more letters next to his name."
Malcolm Jefferson planning three-strong assault on day one at Cheltenham
Malcolm Jefferson is set to launch a three-pronged assault on the opening day of the Cheltenham Festival.
The Norton-based trainer is no stranger to success at the showpiece meeting. Tindari and Dato Star were both Festival winners in 1990s, while in 2012 Jefferson enjoyed a double with Attaglance and Cape Tribulation, both of whom followed up at Aintree a few weeks later.
This year's small but select team is headed by Cyrus Darius, who will line up in the Stan James Champion Hurdle as a big outsider.
The eight-year-old bolted up at Aintree in the spring of 2015, but was injured on his chasing debut at Perth and was sidelined until his comeback at in the Champion Hurdle Trial at Haydock in January.
Having blown away the cobwebs, he got back on the winning trail in last month's Morebattle Hurdle at Kelso and Jefferson is hoping his 66-1 shot can outrun his odds.
"We think it's worth taking a chance with Cyrus Darius in what looks an open Champion Hurdle," said the trainer.
"I was delighted with his first run back at Haydock. He was bang there until the second-last, so it was a very good run for such a big horse who'd been off a long time.
"He quickened up well to win at Kelso, he's got sporting owners and we'll see what he can do.
"On his Aintree form, I think he'd have a bit of a chance."
Cloudy Dream, who won his first two starts over fences before bumping into Buveur D'Air at Haydock and Forest Bihan at Doncaster, is set to take on the mighty Altior in the Arkle Trophy.
Jefferson's third and final runner at this year's Festival will be Double W's, who will contest the Close Brothers Novices' Handicap Chase.
Jefferson said: "All being well we'll run the three of them on the first day and they all seem in good form. Cloudy Dream looks tremendous, as does Double W's.
"We know the Arkle will be a tough race, but they're all tough races at Cheltenham.
"Double W's is near the top of the weights in the novice handicap, but there'll only be about 10lb from top to bottom, so we're not too worried about that."
Riding plans fluid for Stayers' Hurdle favourite Unowhatimeanharry
Trainer Harry Fry is not yet in a position to confirm who will replace the sidelined Barry Geraghty aboard Sun Bet Stayers' Hurdle favourite Unowhatimeanharry.
Geraghty will miss the Cheltenham Festival after suffering a punctured lung and six broken ribs in a fall from Charli Parcs in the Adonis Hurdle at Kempton last Saturday.
It is widely expected that Noel Fehily will get back on board Unowhatimeanharry.
Fehily guided the nine-year-old to each of his four victories last season, including in the Albert Bartlett Novices' Hurdle, before the horse was snapped up by Geraghty's retaining owner, JP McManus.
Fry said: "We haven't had that conversation yet. I'm sure JP and Frank (Berry, racing manager) will discuss it and as soon as they've decided they'll let me know.
"Everything is good with the horse. He seems very well at home and we're very happy with where we are with less than a fortnight to go.
"It's very disappointing for Barry and we all wish him a speedy recovery."
The Seaborough-based trainer has yet to make a final decision at which Festival prize the exciting Neon Wolf will take aim.
The son of Vinnie Roe is ante-post favourite for the Neptune Investment Management Novices' Hurdle, but Fry is still not ruling out a tilt at the Supreme.
"He worked after racing at Wincanton on Wednesday and we're very happy with him," the trainer added.
"We're pleased to see all the rain there is around at the moment.
"He'll be left in both races at the six-day stage, so we'll see what both races are looking like and what the ground is like before deciding which way we go."