Rockers Blues Traveler have axed a series of shows so frontman John Popper can undergo an operation on his spine.
Popper has released a statement, apologising to fans for postponing the concerts, but revealing he has to go under the knife "fast".
"It seems that there is an issue with my spine that if treated quickly will ultimately have me up and running in 2 weeks," he wrote. "If neglected, as it has been, it would be far worse to the point of paralysis so need to take care of this now (sic)."
"I’m only sorry we couldn’t identify the problem sooner and forgo being forced to postpone, reschedule or in some cases cancel upcoming appearances," the Conquer Me singer continued. "We take any such actions very seriously and can only assure you that a very tight second to my physical health and that of my family, is the quality of our shows and a sense of reliability to you that we all take pride in.
"I’m afraid now I’m going to have to rely on you for your patience and positive thoughts. I want to thank you all for being with us through all this as well as for your thoughts and prayers. Will keep you posted on my progress."
Popper has been experiencing "drastic weakness in (his) right arm", revealing three vertebrae in his spine collapsed some time ago.