The 23-year-old full-back suffered a horrific, career-threatening leg injury during the Men of Gwent's Magners League defeat by Cardiff Blues in April 2010.
In all Thomas fractured his leg in five places, ruptured ankle ligaments and dislocated his ankle. But he is targetting a remarkable return at the end of the month - less than a year after the injury.
"I just can't wait to get fit and back playing," said Thomas, who played 15 Magners League games for the Dragons last season.
"My goal is to get back into the side and cement my place for the second half of the season."
Thomas returned to action for Pontypool, in the Welsh Premiership, on Tuesday and could be in line to make his league return against Edinburgh on February 11.
"It's been a tough process," said Dragons conditioning coach James Knight. He's back into skills sessions. We hope to have him back at end of January.
"Martyn's been out for a long time after his lower leg injury and he's also had a hip operation since. As a result of this, his rehab was initially pretty chaotic, and it's been a tough process."
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