[Early diagnosis of a long spinal cord infarction lesion based on concurrent erector spinae muscle infarction: a case report].

We present a case of a 53-year-old man who was admitted with lower back pain and bilateral lower limb weakness. Neurologically, he exhibited paralysis of both lower limbs, complete sensory loss below the 10th thoracic spinal level, and bladder and rectal dysfunction. Spinal MRI revealed intramedullary high-signal lesions extending from the 10th vertebral level to the conus medullaris on diffusion-weighted and T₂-weighted images. By the 10th day, the extensive intramedullary lesion had progressed to the 2nd vertebral level. Although aortic angiography on the 3rd day showed no vascular abnormalities, concurrent infarction of the paraspinal muscles at the 2nd lumbar vertebral level was confirmed. Based on the spinal vascular anatomy, it was deduced that both the spinal cord and the paraspinal muscle lesions had the same vascular etiology. Therefore, the spinal cord lesion was diagnosed early as spinal cord infarction. In cases of acute spinal symptoms, the coexistence of paraspinal muscle infarction observed on contrast-enhanced CT can assist in diagnosing spinal cord infarction.