Gemma Carlisle took to Twitter to reassure supporters that her husband is stable.
Clarke's very poorly but he's alive and stable. Best Christmas gift we as a family could wish for. Thanks again.
The Professional Footballers' Association have visited Carlisle in hospital.
In a short statement it said: "Everyone at the PFA is keeping Clarke Carlisle in their prayers and thoughts.
"We visited Clarke at the hospital yesterday and we are offering our full help and support to him and his family at this difficult time."
Footballers who know Clarke Carlisle as a colleague and former chair of their players' association have tweeted their shock at the news of his involvement in a collision with a lorry.
Just heard the news about Clarke Carlisle. My thoughts are with his friends and family.
Shocked to hear the news tonight about Clarkey, thoughts with him and his family. Pull through mate
Messages of support flood in for former Northampton Town player Clarke Carlisle, after reports he has been seriously injured in a crash.Read the full story ›
Former Northampton Town player Clarke Carlisle has been seriously injured after being hit by a lorry.
Reports say it happened on the A64 in North Yorkshire at 7.30am this morning.
North Yorkshire Police would only confirm that a man was airlifted to Leeds General Infirmary with serious injuries after the accident. It is appealing for witnesses.
Sending our thoughts and prayers to Clarke Carlisle and his family at this difficult time.
Clarke is an inspiration and a fighter and we are sure all Cobblers fans will join us in wishing him well
Northampton Town have signed Leicester City midfielder Ryan Watson on loan until January.
The 20-year-old joined Leicester a year ago, and has been part of their development squad since.
Ryan is a player we have tracked since last Christmas. I have seen him play at least half a dozen times and he has impressed me.
He is an all round good midfield player. He gets about the park, he is strong in the tackle and he can pass the ball well. He wants to come and play senior football and that is a really refreshing attitude.
We have tried to bring him in before and I am really pleased we have been able to get the loan completed now. Thanks to Leicester City for allowing us to borrow Ryan, there is a good relationship between the clubs. They know we will look after him, he will help us and he will also gain valuable experience at the same time.
Northampton Town's new manager Chris Wilder has been talking about his decision to leave Oxford United for Sixfields. The press conference is still going on. We'll have more details as the morning goes on
Today's League 2 game between Torquay United and Northampton Town has been postponed because of a waterlogged pitch.
No new date for the game has yet been arranged.
Northampton Town have signed 19-year-old Everton striker Hallam Hope on a month's loan.
The forward joined Everton from Manchester City in 2005.
The team have also signed **Gillingham striker Antonio German on a month's loan.