Rheumatology and Musculoskeletalcommon
A 69-year-old man presents with 2 months of progressive low back pain that is worse at night and is not relieved by rest. He has lost 6 kg unintentionally and has a history of treated prostate cancer. Examination shows focal percussion tenderness over the lumbar spine but no limb weakness or sphincter disturbance. Which imaging investigation is the most appropriate next step?