EE stepped into van at the start of shift, felt pain in right lower back & the back knee. Pain stopped. Worked the shift. Pain started at end of shift. Reported the incident at 3:30am 11/10/2022. EE was met at Clinic and given restrictions, worked for rest of day. 3 schld days off.11/14/2022 at follow up Occ-med no improvement, went lost time. Back to work restricted duty 11/21/22.