Wed Feb 28, 6:19 PM ET
Brinkley hurt her back during a ski trip in Aspen, Colo., in December "and (it) worsened in the past few days," Horowitz said.
She is expected to be released Friday, said Horowitz, who didn't identity the hospital.
Last year, Brinkley was the subject of tabloid fodder after reports surfaced that her fourth husband,, had an affair with an 18-year-old woman he employed.
Brinkley filed for divorce in September.
The 53-year-old supermodel, who has frequently appeared in Sports Illustrated's annual swimsuit issue, was previously married to developer Richard Taubman, Frenchman Jean-Francois Allaux and singer. She has three children.
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