TEMPE, Ariz. -- Carson Palmer's injured right shoulder is still structurally sound and won't require surgery, a visit to a spine specialist revealed Wednesday.
Palmer was diagnosed with an axillary nerve contusion in his right shoulder, a source confirmed to ESPN.
The injury, which has caused Palmer to miss the Arizona Cardinals' past two games, isn't career-threatening or season-ending, the specialist said. But the veteran quarterback still returned to Arizona without a cure.
"We've turned over every stone," Palmer said. "We've exhausted everything. One of the things I've learned is that nerves are very finicky and they're very unpredictable. It's not a sprained ACL where it's a two-to-four week thing. This is just something you got to continue to work and when it's ready, it's ready.
"So, we're just going to continue the same rehab process and continue working at it and trying at it and this thing will come back and I'll be ready to go."
Palmer was seeing progress until late last week, when his shoulder regressed after throwing for two days during the Cardinals' bye week. The 34-year-old said the nerve was agitated immediately after throwing. He was only throwing at about 20 percent of his normal velocity, too.
Palmer hasn't gauged how far he can throw since the nerve was agitated again, but Cardinals coach Bruce Arians estimated he was throwing 30 to 40 yards.
The injury is rare, Palmer said. The doctor from Wednesday told Palmer he had a 1-in-100,000 chance of hitting the nerve right where Palmer did.
"I could get hit thousands of times," Palmer said. "It just happened that my arm was in the wrong position. I landed directly on the nerve and put enough pressure on the nerve to just shut it down.
"It's been a frustrating process. It's one of those things where there's not a simple answer. It's not a two-week thing, a three-week thing, you have to do this and it's fine or you do that and it's fine."
Palmer can add a spine specialist, who was reported to be Dr. Robert Watkins in California, to the long list of doctors and specialists he's conferred with, which also includes nerve and neck specialists.
"This is not a typical football injury," Palmer said. "The doctor I saw yesterday sees them a lot in car accidents. So, it's not something that's just kinda run-of-the-mill that the training room sees all the time."
If Arizona played Denver on Friday, Palmer said he wouldn't be on the field. On Wednesday, Arians said he wanted to see at least a practice-and-a-half out of Palmer before letting him play against the Broncos. If Palmer doesn't practice Friday, there's still a chance he could be the backup to Drew Stanton, Arians said. Although at this rate, it doesn't look likely Palmer will be healthy enough to be active.
But even though Wednesday's doctor visit didn't produce any miracles, Palmer said he and the Cardinals' training staff will continue to try any and every possible cure.
"You've got to push it," Palmer said. "You can't just sit back and cross your fingers and pray and hope. You've got to try new things, like they've been doing."