The diagnostic lumbar medial branch block for low back and radiating to lower extremity due to lumbar facet joint pain has been traditionally done under fluoroscopic guidance. Some recent studies have shown that the diagnostic lumbar medial branch may alternatively be done under ultrasound guidance. This proposed technique has many advantages, avoid radiation exposure and decrease waiting period for patients to have a pain procedure for low back pain. The time taken, patients' satisfaction score, pain score, the distance the needle tip placed under ultrasound and the ideal position visualized under fluoroscopy will be measured. This study will be done in 2 parts. The first part will determine landmarks for ultrasound. It will involve using 5 cadavers. The second part of the study will involve 25 patients. The needles will be placed initially with ultrasound and then will be verified with C-arm fluoroscopy. Certain criteria will be used to determine its feasibility, for example, less than 20 minutes, less than 5 mm.