Specialists have deemed it unsafe for Mason to continue his career and he announced his retirement on Tuesday morning.
Now, over a year on from the injury, Mason has retired due to the advice of medical professionals.
Mason described the injury as "life-threatening" and said the decision, from a medical point of view, was a "no-brainer". And I think Ryan has explored everything he can.
"But a few weeks ago I had a follow-up CT scan and it revealed an issue with the brain that wasn't shown before".
Sky Sports Wins Premier League TV Rights
But the escalation in domestic rights, which had increases of 70 percent in 2012 and 2015, appears to be at an end. Sky specified that its four packs won are for 128 games per season, up from the 126 it now shows.
"I have come to terms with it. I'm taking each day as it comes and I'm still dealing with a lot of fatigue". I've gone through that emotional side of it, of having to accept I won't be playing again. I didn't know if he played well or not but I loved him like a man.
In the final part of his post, he thanked his family and friends.
"Now I can look forward".
Having joined the club's academy at the age of eight, Mason spent 17 years as a Tottenham player before signing for Hull in 2016.
And in the immediate aftermath of their 2-2 draw against Juventus in the Champions League, Pochettino was keen to send his regards to Mason, assuring him that the "door is always open" for Mason to work with the Spurs coaching staff.
Ash Wednesday & Valentine's Day — What's Trending Wednesday
" Valentine's day and Ash Wednesday are on the same day this year. take ya girl out to mass #bestdateever ", one person tweeted. On Wednesday, Christians will celebrate Ash Wednesday, the solemn beginning of a period of prayerful reflection and penance.
"I'm keen to stay football one way or another, it would be a shame to walk away from the game", he added.
"I remember very, very well how we found him", Pochettino remembered.
Mason's former Spurs teammates paid their respects to him in the aftermath of his injury.
"After only a few tactical training sessions he was quick and he understood everything - the movement and the timing and the concept - that maybe for another player it takes a whole season, and I said "we have in front of us a very good player". He made 20 appearances for Hull before the incident last January. I have lived my dreams and I have achieved absolutely everything that I wanted to.
DREAMERS DITCH DEMS: DACA Recipient BLASTS PELOSI, Thanks TRUMP for 'Leadership'
In his order, Garaufis acknowledged the Trump administration absolutely has a right to change immigration policies as it sees fit. Created by the Obama administration through executive action in 2012, DACA now protects almost 700,000 Dreamers from deportation.