Case of lumbar ligamentum flavum hematoma with epidural hematoma resulting in cauda equina compression

BACKGROUND: Lumbar ligamentum flavum hematomas (LFHs) are rare. However, when they occur and contribute to epidural cauda equina compression, timely surgical intervention is frequently warranted. CASE DESCRIPTION: A 69-year-old female presented with the left lower extremity sciatica and gait disturbance of 2 weeks’ duration that ultimately evolved into a paraparesis/cauda equina syndrome. When the lumbar MRI revealed left-sided L4-L5 epidural compression attributed to a hemorrhage into the hypertrophied ligamentum flavum (HLF), she successfully underwent a bilateral fenestration/decompressive procedure. Pathologically, neovascularization and rupture of the ventral layers of the degenerated and thickened HLF contributed to the LFH. CONCLUSION: Arterial neovascularization (i.e., arterial feeding vessels from paramuscular/prelaminar lumbar branches) contributed to a left-sided L4-L5 LFH that resulted in epidural cauda equina compression in a 69-year-old female. Following surgical focal fenestration/decompression, the patient’s symptoms/signs resolved.