After missing much of the pre-season with a degenerative back condition, Grima was sidelined by a foot injury from the end of round seven until last Sunday, when he played half a game in the VFL with Werribee.
Grima told AFL.com.au on Wednesday that his injury had involved the navicular bone, but stressed it had not been "too serious".
After trying to manage his foot for about a month leading up to round seven, Grima said he and North's medical team decided after the Roos' loss to the Gold Coast that he needed a 12-week rest.
"Anyone who's had that (navicular) injury would tell you that it's not an area that you want to be mucking around with," Grima said.
The key defender said he got through last Sunday's VFL game unscathed and would play again for Werribee this weekend, and hoped he would be ready for a senior recall in round 21 against the Western Bulldogs.
Not that Grima is about to rush things.
He joked that he had tried to convince Brad Scott that he was ready to make his senior return this Saturday against Greater Western Sydneyl.
But the resident club comedian, who has appeared on Fox Footy's The Bounce and SEN radio during his time on the sidelines, takes his football more seriously than he sometimes lets on.
"I was blowing pretty hard in the VFL (last Sunday) so I don't want to rush it," Grima said.
"It's my last chance to really get going for the year, so I've just got to be a bit smart and not get too excited."
Despite being an almost automatic selection in North's team since 2010, injury has restricted the key defender to just 79 games in his seven seasons at Arden Street. He has never played more than 17 in a year.
"It's been done to death that I've been injury prone. I'm pretty much held together with sticky tape these days," Grima joked.
"I'm probably a bit envious of the guys who train every week and play every week, but the reality is I haven't been able to do that in my seven years.
"But if we can come back and play a final, and win a final and strive to do something special as a team - I don't care how long I'm on the sidelines as long as I'm part of that.
"If I can get back and play in (the finals) then I'll still look at this year as a positive even though I've missed 13 weeks."
