STUDIO CITY (CBSLA.com) — Keith Emerson kept secret a debilitating physical pain that affects millions, one expert says.

Emerson of Emerson, Lake & Palmer shot himself last week in his Santa Monica home. He was 71.

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“Musicians can’t talk about it because they won’t get another gig if word gets out that they’re in pain so they keep quiet,” said Jill Gambaro, a carpal tunnel syndrome expert in Los Angeles.

Gambaro says she was emailing back and forth with Emerson for her book about his battle with focal dystonia, which is in the same family as carpal tunnel, a syndrome that causes nerve pain in the hands.

Part of the email that she says is from him reads:

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“Some musicians have resorted to suicide [and] others have gone into teaching. It’s one hell [of] a toughy to deal with. People now understand about AIDS and to some extent cancer, but try mentioning focal dystonia.

“[It] can really be a hindrance in a career forward … To most people Focal dystonia is a place in Europe.

“I’m in touch with musicians who have symptoms and I try and help them.”

Gambaro believes a battle with nerve pain helped drive Emerson over the edge.

“It’s very common for a chronic pain patient to become depressed. It’s very common for those patients to resort to suicide,” she said.

Emerson’s publicist declined to comment on the musician’s health issues but the coroner’s office claims depression as a possible factor in his suicide.

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The Daily Mail reports his girlfriend told the publication that Emerson was tormented with worry about his upcoming concerts because of the nerve damage in his hand.