May 17, 2007 -- "THE Office" star Jenna Fischer won't be going back to Buddakan any time soon. The pretty brunette was celebrating her series being renewed Monday night with friends when she slipped on the restaurant's marble steps and fractured four bones in her back. A friend said she spent the night in St. Vincent's hospital and had to cancel an appearance on "Late Night with Conan O'Brien" and a Harper's Bazaar shoot. Fischer's rep, Lewis Kay, said yesterday she's "doing much better and is resting at her hotel. Her husband [director James Gunn] flew in to be with her." bummer. ouch.