Unexplained back pain and sciatica: the added value of upright dynamic MRI of the lumbar spine in cases of clinical/radiological mismatch

Background: Degenerative disease of the lumbar spine is one of the most prevalent pathologies worldwide, and MRI is the gold standard imaging modality that helps to assess soft tissue and bony abnormalities and elicit causes of neural compression. It is not uncommon in the daily practice to have patients presenting with neurological symptoms during standing or walking while MRI fails to detect lesion that explains their clinical picture. The aim of this study was to detect changes that appear on dynamic weight-bearing MRI of the lumbar spine that was hidden on conventional supine MRI and to correlate them with the clinical situation. Methodology: Ninety patients with back pain were enrolled in the study, they did conventional and dynamic MRI of the lumbar spine. We compared findings in both modalities as regard alignment, ligamentum flavum buckling, foraminal narrowing and neural compression. Results: Dynamic MRI showed neural compression in 87% of patients in comparison to supine MRI, ligamentum flavum buckling was reported in 80%, neural foraminal narrowing was seen in 24%, exaggeration of the lumbar lordoisis in 10% and exaggeration of the already existing disc protrusion was documented in 60% of the included patients. Conclusions: Upright dynamic MRI has added to supine MRI in problem solving cases with clinical radiological mismatch. The results indicated changes in the spine alignment, neural compression and spinal canal stenosis. Since the examination is non-invasive, it could be used in the preoperative planning of patients with degenerative lumbar spine disease.