LOS ANGELES — Didi Gregorius has finally received an explanation for the inflammation in his right elbow. He was diagnosed Tuesday with pseudogout, Phillies general manager Sam Fuld said.

“There are calcium crystals that formed in the blood. It’s a pretty rare condition,” Fuld said. “But it’s one that is not particularly concerning. We spent the last couple of days just trying to identify the best plan of care.”

Pseudogout is a “form of arthritis characterized by sudden, painful swelling” in a joint, according to the Mayo Clinic. Gregorius has not played for the Phillies since May 12, as his elbow swelled. He thought it was caused by diving for a ball or being hit by a pitch. But the inflammation failed to subside and he felt discomfort last week during his rehab assignment with triple-A Lehigh Valley.

“I think it just took a long time to figure it out and get some clarity,” Fuld said. “But he’s seen multiple doctors. Everybody seems to be aligned and on the same page now. Finally, for Didi’s sake, we can get him at the 1-yard line in creating a clear plan. It’s frustrating for him and everybody else involved. But him in particular. Whenever you get hurt, you want to have a clear path to get back. So I feel for him.”

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The Phillies re-signed Gregorius in January to a two-year contract worth $28 million. He was the only shortstop this winter to land a multiyear deal, but he has played just half of the team’s first 64 games.

Gregorius is with the IronPigs in Worcester, Mass. and is excepted to resume his rehab assignment this week. If so, he could rejoin the Phillies when they return home Tuesday.

“It’s just really about finding some medication that puts him in the best spot. As soon as that is sorted out, which we should have clarity on that very soon, he’ll go back to baseball,” Fuld said. “He’ll be getting out there in a Lehigh Valley uniform pretty soon. That’s the plan, and I think that’s the full expectation. We’re confident that will work itself out.”