Ligamentum Flavum Hematoma in the Lumbar Spine

—A Report of Two Cases—

Abstract

We report here two cases of ligamentum flavum hematoma in the lumbar spine who presented with radicular symptoms and cauda equine claudication. The first case was a 71-year-old man who complained of left gluteal region pain after falling on the ground. Five months later, the patient suffered gait disturbance, and MRI demonstrated spinal canal stenosis at L4-L5, caused by a left posterolateral mass lesion continuous with the ligamentum flavum. The second case was a 56-year-old man who complained of low back pain and bilateral gluteal region pain after lifting a desk. MRI showed spinal canal stenosis at L3-L4, caused by a posterior mass lesion continuous with ligamentum flavum. Two months later, he had obvious intermittent claudication with bilateral gluteal region pain after low back extension. Second MRI revealed that the mass lesion had expanded and changed signals. In both instances, surgical treatment was performed with partial laminectomy and excision of the degenerative ligamentum flavum containing hematoma, resulting in excellent pain relief. Histological findings confirmed the diagnosis of old hematoma with granulomatous change in the degenerative ligamentum flavum.