The fracture was caused when Giugliano crashed in race two last week at Laguna Seca in the US. Initially he was examined by doctors, after the crash, who found no issues after an X-ray.
Having been out of action at the start of the season due to an accident at Phillip Island in February, more tests were carried out on his return from the US where MRI and CAT scans picked up the fracture to his D3 vertebra.
The injury means Giugliano will not be able to ride his bike for three months.
"I am of course extremely disappointed right now… Clearly 2015 was not my season," said Giugliano.
“There is no point grieving over it anyway, that's that and the important thing is that once again the trauma will not result in any long-term damage.
"It will take a bit more time, but I hope to recover quickly and be back riding my Panigale soon," he added.
The Italian will not be replaced by Ducati for the August 2, Malaysian GP at the Sepang circuit.