It's not a matter of if, but when.
I hate to assume anyone will be in pain or unable to do what they love, and I sure wouldn't wish it on anyone. With Jack Wilson, though, we're just sitting back and waiting.
He's supposedly down 12 pounds, or 22 pounds, depending on who you believe or from what date. He's saying he's learned from his injury history and is taking precautions to not get hurt again.
If he does go down again, though, the team has added a bunch of middle infield depth and won't have an issue replacing him.
If he goes down sometime before June, Brendan Ryan will slide from second to short, and Adam Kennedy would likely take over at second. If it's after June, it'll be Dustin Ackley moving in at second (if he hadn't already) and Ryan still the man handling the six hole.
Quite honestly, Wilson isn't a guy the Mariners should be relying on anyhow. There is a massive shortage of shortstops who can hit in this league, so any number of all-glove guys could replace him, with Ryan being the obvious candidate. The team will be better off once he moves out of the position, be it through injury, demotion or release.