The 26-year-old Scotland international spent 15 months on the sidelines after requiring surgery to correct severe hip damage suffered on the opening day of last season.
Callam began the 2008/09 campaign with high hopes for both club and country but his season was ended almost before it began during the Magners League clash against Munster on September 5.
The former Scotland Sevens star could only sit and watch as his Edinburgh team-mates secured a second-place finish in the Magners League, only missing out on the title thanks to Munster's fine form.
Fastforward a year and three months and Edinburgh are again sitting second in the league standings and Callam is finally back in the thick of things.
Callam has missed a total of 24 Magners League games since being taken off against Munster at Murrayfield but his lengthy absence came to an end during the trip to the Scarlets last Saturday - a return that coincided with a superb Edinburgh win.
"It is good to be back - it has been 15 months since I last played for Edinburgh and it is good to see all of the hard work I've done in the gym being put to good use," Callam told Edinburgh's official website.
"I had prepared a lot for the game and it was the next level up and a bit faster pace of rugby than what I've played before.
"But it wasn't overwhelming and I really enjoyed being back on the pitch.
"The forwards worked really hard for the whole 80 minutes. It wasn't a pretty game of rugby in wet conditions. But we got what we deserved in the end - a win."
Callam now has his sights set on more game time with the Scottish capital outfit as they continue to push for a place in the end-of-season Magners League play offs.
Capped 11 times by his country, Callam's return to rugby has been low key so far.
The game against the Scarlets in West Wales was preceded by two appearances for Boroughmuir and another for representative side Gael Force in the new British and Irish Cup.
But despite having to begin his reintroduction in the lower echelons of the game, Callam knows the experience will stand him in good stead as he and Edinburgh look to make a name for themselves throughout the rest of 2009 and 2010.
"It is all good - that is four games for me now and I feel like I'm back in the mix," added Callam.
"Hopefully I can keep it going and get more games for Edinburgh in the near future."
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