The large majority of back pain is musculoskeletal and improves on its own within a few weeks. However, certain red-flag signs point to serious conditions that need emergency assessment. These include new loss of bladder or bowel control, numbness around the genitals, buttocks or inner thighs (saddle anaesthesia), and weakness or numbness spreading down both legs. Together these can signal cauda equina syndrome, a surgical emergency.
Other warning signs include back pain with a high fever (possible spinal infection), unexplained weight loss, a history of cancer, back pain following major trauma such as a car crash or fall from height, or severe pain that is worse at night and not relieved by rest or position change. Anyone on blood thinners or with a weakened immune system who develops sudden severe back pain should also be assessed promptly.
If any of these features are present, do not wait to see if it settles. Call your local emergency number or go to the nearest emergency department. For ordinary back pain without red flags, a telehealth consultation with a doctor can help you manage symptoms and decide whether in-person assessment is needed.