Dowling suffered the injury against the Ospreys last September. During his career in the red of Munster, Dowling has made 97 appearances and was part of the 2009 Magners League winning team.
But his career has been blighted by a number of injuries. He missed much of last season with a knee injury and the game against Munster was just his third competitive match since his return to fitness.
"It's been a fabulous experience. I've made some great friends and take with me really great memories, I've had wonderful times with Munster," said Dowling.
"In fairness I've received all the help and assistance I could have asked for from the Munster medics and I'm hugely appreciative of all the time and effort they've put in trying to get me back.
"We've explored every avenue possible but in the end I know this is the right decision, the only one really."
During his enforced absence, the 28-year-old has begun a Physiotherapy degree at Limerick University.
"I'd have to say I'm excited about this new direction. A lot of the skills that I needed to bring to professional rugby are transferable to what I'm doing now.
"But again I have to thank the course director who has been so supportive in facilitating my studies while I was also rehabbing this injury.
"I've been fortunate really. I had a great career as a professional rugby player. Enjoyed success with Munster. Got to travel the world. And am lucky now to be in the position I'm in with a new career hopefully beckoning.
"But there is a lesson here for all those looking to follow a pro rugby path. It can end abruptly. Keep that in your mind if you're sitting in a classroom with only dreams of playing in Thomond Park.
"I'd like to thanks all those who have supported me in my career, the coaches, fitness guys, all involved with Munster and Ireland and close friends with particular thanks to my parents John and Kitty, sister Catriona and girlfriend Gill who were always there for me in good times and bad.
"And finally, to the Munster fans, the best in the world, my heartfelt thanks for the part you played in making mine such a memorable career."
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