Hi, Thanks for writing in. The pain you might be experiencing is from the injury to spine. I suppose you have got X rays done which indicate injury to vertebrae L 4 and L 5 levels at lower back. This can cause severe pain in the region and is not related to your kidneys in any way. You probably need a MRI scan of your lower back spine to know if there is injury to the bones and discs. This can cause pinching of nerves and pain is experienced along the area supplied by the nerves. Rest and avoiding heavy physical activities is important and this will heal your injuries quickly. There might also be muscle spasm in the lower back which might be treated with an ointment containing a pain killer and muscle relaxant applied gently about twice a day. You can also apply hot or ice packs.