Ligamentum flavum hematoma presenting as progressive root compression in the lumbar spine

Study Design This is a case report. Objectives To provide a better understanding of a rare entity, ligamentum flavum hematoma, based on a successfully treated patient. Summary of Background Data Lumbar root compression is frequently caused by disc herniation. Canal stenosis, epidural hematoma, or tumors are less common. Few cases of hematoma in the ligamentum flavum causing lumbar root compression have been described. Methods A patient was treated for ligamentum flavum hematoma causing progressive lumbar root symptoms. Clinical and radiologic features, including magnetic resonance images, were recorded. Results Symptoms consisted of progressive lumbar root deficit after mild physical exertion. On magnetic resonance images, a mass continuous with the ligamentum flavum, compressing the dural sac and roots, was found. Areas of high signal in T1 were present in it. In this patient, removal of the ligamentum flavum (degenerated tissue containing hematoma) resolved all of the symptoms. The diagnosis could have been suspected based on clinical history and magnetic resonance imaging. Conclusions Magnetic resonance imaging can provide a basis for diagnosing ligamentum flavum hematoma. Removal of ligamentum flavum is the treatment of choice.