"I'm obviously disappointed at being forced to retire," he said. "It was always going to be really tough coming back from an injury like that but it's still a big blow."
Hall joined the Dragons in 2008 from Nottingham, making his debut in the festive fixture against the Scarlets on January 1st 2009. A strong player both in the scrum and in open play, he has been a key member of the Dragons squad, making 28 appearances for the region despite a 6-month lay-off with shoulder surgery following an injury in the Heineken Cup game against Gloucester in October 2009.
"It's been really tough for me. I was at Nottingham for 5 years and played every game so to have 2 major injuries during my time at the Dragons has been really unlucky."
"I'd like to thank everyone at the Dragons who have been really supportive during my rehab. It was easy to move down here and fit in with the squad and I wish them all the best of luck going forward."
Dragons Director of Rugby Robert Beale said "Nigel has been a model professional during his time at the Dragons and his retirement will leave a big hole in our squad.
"I would like to thank Nigel for his honesty and commitment to our organization and wish him and his family the very best of luck for the future."