Defendants' medical evidence established that plaintiff did not suffer a serious injury causally related to the accident. Their radiologist opined that the herniated discs in plaintiffs lumbar and cervical spine were degenerative and preexisting, and thus not caused by the June 2006 automobile accident. In response, plaintiffs medical expert, while noting that the herniated discs shown on the MRI correlated to his range-of-motion and other studies, failed to address or rule out injury from a preexisting degenerative condition, or to offer competent medical proof that plaintiff could not perform substantially all of her normal activities for 90 of the first 180 days following the accident ( see Valentin v Pomilla, 59 AD3d 184).