Lansbury tripped and fell at a July 8 salute composer Stephen Sondheim at the Hollywood Bowl. However, she was scheduled to have the surgery before the accident, and the date with the doctor is not the result of the mishap, according to a spokesperson for the Hollywood Bowl. Lansbury, 79, told the trade that she first injured her left knee while working on the film "Mrs. Santa Claus" in 1991. The performance — entitled Stephen Sondheim's 75th: The Concert — featured the talents of Jason Alexander, James Barbour, Carol Burnett, Len Cariou, Barbara Cook, Stephanie D'Abruzzo, Jason Danieley, Alexander Gemignani, Josh Groban, Anne Hathaway, Marin Mazzie, Eric McCormack, Audra McDonald , Bernadette Peters, Elaine Stritch, Jubilant Sykes, Vanessa Williams and Adam Wylie.
Lansbury and Cariou performed "A Little Priest" from Sweeney Todd. Lansbury will be hospitalized five days and in physical therapy for a month.