A couple of points of analysis:
If he has surgery, he will be one of several big leaguers to have recent hip surgery. Because we don't know the specifics of his issue and how it compares to other players, we can't learn too much (plus Myers is a pitcher). But for what it's worth, Mike Lowell and Chase Utley had their surgeries in October and November, respectively, and both have returned to full strength. Alex Rodriguez's surgery was in March, and he returned May 8 and has played well since. Carlos Delgado and Alex Gordon have had more recent surgeries and are yet to return.
The speculation about trading for a starting pitcher should now get more serious. Before, though the Phillies were considering all options, the whole discussion had a sensationalistic, talk radio feel. Now, they should go get a guy. This is a team built to win now, with position players in their prime. The rotation was troubled enough to begin with, and the internal options are not satisfying. Kyle Kendrick is still working on his command in Triple-A; Carlos Carrasco is struggling big time; Drew Carpenter, in that spot start against the Nats, did not pitch aggressively enough with a lead, and demonstrated that he is not ready; Chan Ho Park, the team believes, is better suited to the bullpen.
The Phillies style, as you know, has not been to trade for the Jake Peavys of the world, but the Jason Marquis (see Blanton, Joe). That's not to say they won't step out of character, but their payroll is already pretty high. My opinion? Mortgage the farm to get a good pitcher, if that is possible. This is an organization built to win now, and the rotation is the only thing holding them back from dominating the division. It was the biggest issue before Myers' injury, and now is huge. He had been inconsistent this season, but was improving. It is imperative that, should they lose him, the Phils replace Myers with a quality big league arm. There is no minor leaguer who should be untouchable in a deal.