Acute low back pain, uncomplicated and lasting less than 4 weeks, without red flag signs typically responds well to medical treatment and physiotherapy. In such cases, imaging often does not reveal a specific cause of the pain. MRI is the most informative method for diagnosing lumbar radiculopathy, especially when conservative treatment fails. Currently, the national clinical protocol for imaging in lumbar radicular pain does not include a diagnostic algorithm for lumbar neurocompressive syndrome. A total of 102 patients with lumbar neurocompressive syndrome were examined. All patients underwent comprehensive clinical and neurological assessments. In one group of 51 patients, the diagnosis was established using MRI of the lumbar spine. In the other group of 51 patients, the diagnosis was based on lumbar spine X-ray imaging. Among patients in the first group, who were diagnosed primarily via MRI, 37 (72.5%) were examined during the acute phase of pain (within the first 4 weeks of symptom onset), despite the absence of red flag signs. Only 14 (27.5%) patients in this group underwent MRI after unsuccessful conservative treatment. All 51 patients in the second group, who presented with acute lumbar radicular pain without suspicion of serious pathology, underwent primary radiological examination of the lumbar spine in two views. The developed diagnostic algorithm can contribute to improving clinical decision-making and enhancing the quality of life for patients with lumbar neurocompressive syndromes.