James Levine decided Saturday to cancel his part in the New York, Chicago, Philadelphia, Newark and Washington, D.C. shows.
The Boston Globe reports the extent of his injury is unknown but he will be undergoing an MRI.
Levine fell during a standing ovation Wednesday after the BSO's performance of Beethoven's Ninth Symphony.
Conductor David Robertson will replace Levine for the tour, except for Monday's Carnegie Hall performance which will be led by Polish conductor Marek Janowski.
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