Australian cycling star Jay Vine will not have to have surgery on the spine injuries he suffered when falling heavily in a horror crash at the Itzulia Basque Country race. 

His UAE Team Emirates medical director Adrian Rotunno reported on Saturday that last year's Tour Down Under winner would remain in hospital and would be in a neck brace for up to six weeks.

After suffering what the team described as "a cervical and two thoracic spine vertebral body fractures" in Thursday's crash in northern Spain, there had been initial fears that the 28-year-old would need an operation.

"After examining MRI and final clinical assessment, thankfully no surgery will be necessary for Jay. The fractures are stable enough not to warrant surgical correction," Rotunno said in a team statement.

"Jay will remain in hospital over the following days to allow for ongoing observations and further recovery. He will be in a neck brace for up to six weeks but will be able to start with general body rehab from next week."

Vine looked to have come off worst of the dozen who fell in the mass crash that caused serious injuries to other luminaries, including double Tour de France winner Jonas Vingegaard and double world champion Remco Evenepoel.

After the Canberra rider had slid at high speed on a descent into a concrete ditch at the side of a road, he lay motionless while being treated and TV pictures left his wife Bre, a former cyclist herself, fearing the worst.