Which red flags in back pain indicate urgent MRI to assess for spinal cord compression?

• A. Progressive weakness, bowel or bladder dysfunction, saddle anesthesia, or perineal numbness.
• B. Occasional mild back ache with no neurological symptoms.
• C. History of lifting heavy object only.
• D. Pain relieved by rest.

Answer: (A)

Urgent MRI is needed when back pain comes with signs that suggest spinal cord or nerve compression. Progressive weakness shows that motor pathways are slipping toward dysfunction and could worsen quickly. Bowel or bladder dysfunction indicates autonomic involvement and points to cauda equina or significant compression that can lead to irreversible deficits if not treated promptly. Saddle anesthesia or perineal numbness reveals sacral nerve involvement, again signaling compression at a spinal level that demands rapid evaluation. Together, these red flags mean the situation is not just mechanical pain but a potential neurosurgical emergency, so imaging should be obtained urgently to identify the cause and plan decompression if needed. By contrast, an occasional mild back ache without neurological symptoms, a history of lifting a heavy object, or pain that is relieved by rest are more typical of non-emergent, mechanical back pain and do not require immediate MRI.