John James Chalmers suffered arm, leg and facial injuries in the May 2011 blast, which killed two comrades.
The 25-year-old, from Dunfermline, Fife - known as JJ -has undergone a series of operations which have proved successful enough for him to take part in a charity diving trip.
In the latest operation, doctors took part of a leg muscle and used it to create a new tendon in his right arm.
Replacing the severed tricep tendon has given Mr Chalmers - a Lance Corporal with 42 Commando - use of the arm again.
His father, Principal Clerk of the Church of Scotland, the Rev John Chalmers, admits his son's recovery is still a lengthy process.
He said: "As things improve they discover more that they can do to get more use out of his hands and arms.
"They've taken muscle lining from his leg and put that into his arm to replace the tendon that was severed in the explosion.
"Now for the first time in two-and-a-half years he's starting to get use of his tricep."
Mr Chalmers and his squad were hit by an improvised explosive device (IED) while on patrol in Helmand Province. The Royal Marine reservist was so badly injured the right hand side of his face had almost completely collapsed.
Mr Chalmers, who worked as a teacher in Edinburgh, lost two fingers on his left hand and others had to be wired back on.
His right elbow had disintegrated and doctors later had to graft his arm to his stomach to ensure a regular blood flow while they tried to repair it with titanium.
Mr Chalmers said: "There are plenty of frustrating moments where simple tasks defeat me.
"There is something every day that I can't do, but then there is something every day that I've discovered a new way of doing.
"Come the new year, I'll be looking to get more surgery and move forward.
"It's the same rotation - surgery, recovery, rehab, get a bit more time to yourself then do it all again."
Mr Chalmers has just returned from a charity scuba diving trip to the Maldives with the medics who saved his life.
"A doctor that I dealt with in the early days said then that he'd love to run a trip," he added.
"Not just with some injured lads, but with the medical staff who were looking after us to let them see how well we recover.
"Back at that point I thought I'd never be that well.
"We got a huge amount out of it obviously, but the medical staff got a lot out of it too, to see how far we've come since the very early days."
In 2011 Mr Chalmers delivered the Best Man's speech at this brother's wedding, by videolink from a military hospital.
Guests at the wedding stood to applaud as Mr Chalmers appeared on a video screen live from his bed in Birmingham.
Marine Sam Alexander, 28, from Hammersmith, west London, and 23-year-old Lieutenant Ollie Augustin, from Kent, were killed in the 2011 blast.
The men, both from Juliet Company 42 Commando Royal Marines, had been on patrol in the Loy Mandeh area of the Nad-e Ali district.
Speaking at the time, Mr Chalmers said: "I woke up confused, but I knew I'd been blown up.
"I never had a point where I thought 'this is terrible', it was always 'let's get on with it', but then, I don't think I really realised how bad my injuries were."