Evans had spoke of his desire to return to playing rugby but after being told he would never return to the heights that made him an international star he was forced to make the heartbreaking decision.
Evans' former mentor and ex-Scotland winger Roger Baird revealed his devastation for Evans.
"It is devastating for Thom because all you want to do is play top-class rugby for as long as you can, and there is no doubt he would have contributed a lot to Scottish rugby in the years to come," said Baird.
"It is also a huge blow for the Scottish game and the Glasgow and Scotland teams because we just don't have players with his searing out-and-out pace.
"This has been a traumatic time for Thom but he is a strong character who has come through it. Of course it is tough for him to retire at just 25 but he knows things could have been far worse.
"The medical staff helped save him and he has maintained his mobility and he is thankful for that. Thom is an outgoing lad who is very sporty and a big hit with the girls, so he has a lot to live for.
"He will look back on his short rugby career with satisfaction as, in that time, he became one of the best players in the game."