Fracture t7 & t8 with spinal cord injury

My 22 yr old nephew was in a motorcycle accident 2 days ago, he has no sensation or movement from nipple line down. He is in intensive care with with these injuries along with rib fractures and lung contusions. The neurosurgeon told us yesterday if they don't see any improvement in sensation or movement within 48 hours of injury he most likely won't have any improvement . They are trying to stabilize blood pressure so he can have MRI done, we are being told the damage to spine is done so it won't make a difference if MRI is done today or in 2 days. I'm new to spinal cord injury, trying to educate myself and have read that spinal cord injuries can improve up to 1-2 weeks after injury. Any input would be appreciated, TIA, Patty