The club's top try-scorer in Heineken Cup competition burst onto the scene as an academy starlet in 2006, and had played over 100 games for the club when he ruptured his ACL (anterior cruciate ligament) against Sale Sharks in the summer of 2011.
He announced his return in December with six games for the club and a replacement appearance for Scotland A, but was hit by a new injury setback three months later.
After an operation to improve the cushioning offered by his knee cartilage, Cairns will work with the club's physios and strength and conditioning staff with the view to getting back to full fitness and making a case for a new contract.
Edinburgh Rugby managing director, David Davies, said: "When fit, Ben is a quality player of international class and we'll do everything we can to help him back to full fitness.
"He's a local boy who has been a long-standing servant of Edinburgh Rugby, and I believe that commitment merits our efforts to give him the best possible chance of earning a new contract."
Cairns added: "It's been a frustrating couple of seasons for myself and Edinburgh Rugby, who have been fantastic throughout. I'm really grateful for the opportunity to stay part of the squad through this rehab period.
"It means a huge amount for me to represent my home club and I'm determined to repay the faith they have shown in me.
"With this being a completely new injury, I'm confident I can get back to full fitness and the form I know I'm capable of."
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