Bono says he fears that he may never play guitar again following a bike accident in November 2014.
The U2 frontman made the comment in his A to Z of 2014, published on the band’s website.
Bono broke his arm in six places and fractured his eye socket, hand and shoulder blade in what he called a “freak accident” in New York.
In the letter to his fans, Bono said he was unable to move around physically and would have to “concentrate hard” to be fit for U2’s next tour.
At the time, the hospital where Bono was being treated said he had been involved in “a high-energy bicycle accident when he attempted to avoid another rider”.
The 54-year-old rocker spoke this week about being on painkillers for weeks and said he had a “massive injury, I can’t blame on anyone but myself”.
Bono also revealed he now had a titanium elbow.
The wide-ranging, sometimes tongue-in-cheek, A-Z letter covers topics ranging from the iTunes release of the Songs of Innocence album, to an update on his family.
Bono talked about learning from his mistakes adding “the first of which is the discovery that I am not an armored vehicle”.
He says the letter will be his only communication for the first part of this year.
“The consequences of this freak accident are significant enough that I will have to concentrate hard to be ready for the U2 tour in fitness terms,” he said.
Bono added: “As a result I have cancelled every public appearance and decided this missive is all the communication I can manage for the first half of 2015, beyond muttering and singing to myself of course.”
U2’s The Joshua Tree is among 25 new additions to the US Library of Congress’s National Recording Registry.
U2’s 1987 album spawned such hits as With or Without You and Where the Streets Have No Name.
The original cast recording of Stephen Sondheim’s 1979 musical Sweeney Todd and Isaac Hayes’ Theme from Shaft have also been added to the archive.
U2’s The Joshua Tree is among 25 new additions to the US Library of Congress’s National Recording Registry
Established in 2000, the US Library of Congress’s National Recording Registry contains recordings deemed important enough to be preserved for posterity.
Each year, 25 recordings that are at least 10 years old are added to the registry, which now includes 400 deemed to be “culturally, historically or aesthetically significant”.
The oldest of this year’s additions is The Laughing Song, a track by George Washington Johnson – the first African-American to make commercial records – that dates from around 1896.
The most recent, Jeff Buckley’s version of Leonard Cohen’s Hallelujah, was recorded in 1994.
Other familiar tracks to join the registry include the Everly Brothers’ 1960 single Cathy’s Clown, the 1969 Creedence Clearwater Revival track Fortunate Son and Linda Ronstadt’s 1974 album Heart Like a Wheel.