Role of MRI in patients with acute lower back pain. Method: A group of 501 patients who referred unit from orthopedic were subjected to MRI examination and the MRI results were evaluated. All patients with radicular pain, neurological signs or traumatic patients were excluded from this study. Results: 501 patients complain from acute lower back pain , mean age 33.49+8.38 range (20-70), 229 (46%) male and 272 (54%) female , in combined MRI finding with age of patients , we found large number of patient have disk prolapsed (191), with mean age 36.50 , while patient with normal MRI or just muscles spasm were mean age (31.79), so the MRI not effect in outcome of young patient ( below 31 years old ) with a lower back pain. Conclusion: Lumbo-sacral MRI exam have minimal effect in outcome of young patient with acute lower back pain (less than 3wks)