Metropolitan Opera music director James Levine has cancelled his fall conducting engagements after reinjuring his back, and Italian conductor Fabio Luisi has been named principal conductor.

The New York-based Met announced Tuesday that Luisi would be filling in for Levine, who has led performances at the nation's premier opera house for four decades and is credited with turning its orchestra into opera's finest instrumental ensemble.

Levine, who was to start rehearsals Tuesday for the new season, was in Vermont last week recuperating from back surgery. He was walking outside with a cane when he fell and damaged one of his vertebrae, Met officials told The Associated Press.

The 68-year-old musician underwent new surgery in New York on Thursday.

Bigger role for Fabio Luisi

"While Jim's latest setback is hugely disappointing for all of us, he joins me in welcoming Fabio's larger role," said Met general manager Peter Gelb. "I am very pleased that Fabio was able to rearrange his fall schedule, and I appreciate the understanding of those companies with whom he was scheduled to conduct."

Principal guest conductor Fabio Luisi will fill in for James Levine. Cory Weaver/Metropolitan Opera/Associated PressIn order to accommodate the Met, Luisi had to cancel performances with the Rome Opera; the opera company in his native Genoa, Italy; the Vienna Symphony, where he is chief conductor; and the San Francisco Symphony.

"I am honoured to have been asked to take on these additional responsibilities, but my thoughts are also with Maestro Levine," Luisi said in a statement.

Levine remains the Met's music director. Luisi made his debut at the Met in 2005 and stepped in for Levine multiple times last year and earlier this year.

A versatile artist who has often jumped in during unforeseen circumstances, the 52-year-old musician was appointed the Met's principal guest conductor in April of last year. He also is artistic director of the Pacific Music Festival in Sapporo, Japan.

Canadian Derrick Inouye to conduct

At the Met, Luisi will conduct five performances of a new production of Mozart's Don Giovanni, two of Wagner's Siegfried and the Met orchestra at Carnegie Hall. Levine's other fall shows will be led instead by French conductor Louis Langree and Canadian-born Derrick Inouye.

Levine, a Cincinnati native, also was music director at the Boston Symphony Orchestra, but a series of injuries in recent years led to his resignation from that post.

He has had previous surgeries to address spinal stenosis, a condition that causes the spinal canal to painfully narrow. According to his doctors, he was successfully recuperating from back surgeries in May and July when the accident happened while he was vacationing.

Levine hopes to return to the Met in January for the new production of Wagner's Goetterdaemmerung, the company said.