Hypertrophy of ligamentum flavum mimicking lumbar disc herniation.

Abstract

The most common cause of a spinal root compression is intervertebral disc herniation. Although there are patients with clinical and radiological findings of disc herniation, no disc pathology is found at operation. We present the case of a 38-year old man who was admitted in our clinic because of right fifth lumbar (L5) nerve root compression symptoms. Magnetic resonance imaging (MRI) of the lumbar spine revealed a lumbar disc herniation at the four-fifth intervertebral lumbar level (L4-L5). During operation a fold of the ligamentum flavum was found to compress nerve root, which was excised. After the operation the patient had fully recovered. We describe herein this case in order to denote that an image on MRI studies of disc herniation may represent a fold of ligamentum flavum. Thin slices MRI studies of the affected area may be could scrutinize the imaging misdiagnosis.