What does uncinate arthrosis means in a mri?? I'm a 24 years old. I was in a car accident about a month ago..

Damage? You need to discuss the results with the Doc who ordered or did the MRI. Seems likely that your neck was injured and these findings show the extent of damage. Many have some signs of historic damage but you are young, so since there was a recent traumatic event - it is more likely from that. Ask! I hope it goes well.