The troublesome injury, centred around a small bulge on a disc, flared up again before he enjoyed a 60-minute run-out with Munster 'A' against Ulster 'A' last month.
And after a second half appearance for Munster against Edinburgh in the Magners League, he played the full 80 minutes - scoring a try in the process - in last weekend's league defeat to the Cardiff Blues.
Marcus Horan has been delighted to see a player of O'Connell's quality return to the fray with both province and country, particularly with the leadership qualities he brings to the Irish side.
"To see the effort that he's made to come back, it's great. Paul's played with the club, Young Munster, and he's played with Munster and the Munster 'A' team as well," explained the prop.
"He's done everything he can to get back and he's had a setback in between. When guys in the team see what he's gone through to get back that gives us a boost, as well as the fact that you have a guy of his experience on the field.
"It takes pressure off someone like Drico (Brian O'Driscoll). He's further out the field and can't be coming in making decisions at the breakdown or where the forwards are, so it's good to have someone like Paul in there.
"He's definitely someone that leads from the front and sets down a marker. In his absence, a few more guys have stepped up and it's great, as well, that that experience is now there.
"We can just build on that with the other guys in the pack that have gained that experience while he was away. That's key for us as well."
Asked about Ireland's change of hooker for Saturday's pivotal clash with Wales, Horan admitted that having a player back in like Rory Best, who is so eager to reclaim the jersey he made his own during last year's championship, can only benefit the side.
"Rory has a bit more experience (than Bernard Jackman), having played last year in the Six Nations. I suppose for any player it's disappointing to be left out but for Rory now to get back in, it's a big boost and he's going to be trying to prove a point.
"That's a great thing when you see a guy chomping at the bit and it hurts him to be left out for the last two games. A guy coming back into the team like that will give it a bit of a lift," Horan added.
Saturday's game will mark Horan's 55th cap for Ireland and see him overtake Peter Clohessy (54 caps) to move into third place on the all-time Ireland props' caps list, behind Phil Orr (58) and John Hayes (82).
But the Shannon clubman is more concerned about this weekend's opposition than any milestones, with his focus firmly on continuing Ireland's recovery from their World Cup disappointment.
"Watching the games from the last few weekends, Wales are flying high. They're playing with great confidence, similar to the (2005) season when they won the championship.
"For us, we've been building all the way. We've had to deal with a lot of problems outside of the camp and pressure from every direction," he admitted.
"That's been tough but I think our confidence is up now and we're enjoying it. Everyone's relishing playing at Croke Park and that's a massive factor.
"It's a massive game. There's something for both teams to get out of the game and I don't think that happens too much in the championship.
"For us, we have a shot at the Triple Crown and championship in these final two games and for Wales they have the Triple Crown if they win this one. So it makes it interesting for both players and supporters alike."