My Dad Is 92 Years Old And Took A Fall

My dad is 92 years old and took a fall landing on his coccyx 1 week later he was in severe pain .An xray showed severe degenerative arthritis and mild 5mm anterior listhesis of L4 on L5. He cant get into a back doctor for a week and he is in severe pain with standing sitting or walking. There is an walk in ortho clinic that a PA will inject him with cortisone. What would you recommend? He is on celebrex and norco 5 mg without relief. He also had a prednisone burst for 5 days of 30 mg a day.