Symptomatic Ruptured Seed-Type Partial Ossification of the Ligamentum Flavum: A Case Report

Background Seed-type partial ossification of the ligamentum flavum (OLF) causing severe radiculopathy after rupture has not yet been described in the literature. Case Description A 51-year-old man presented with sudden onset severe back pain and right anterior thigh pain without any neurologic deficit after lifting a heavy weight. On preoperative computed tomography, we identified a ruptured seed-type partial OLF at the L1-L2 level. T2-weighted magnetic resonance sagittal and axial images showed thecal sac compression by the ruptured OLF. There was no improvement in his symptoms after 2 weeks of conservative management. The patient had percutaneous full endoscopic interlaminar removal of OLF. Postoperatively he experienced prompt improvement of his symptoms. Conclusion Rupture of seed-type partial OLF causing severe radiculopathy is extremely rare, and percutaneous endoscopy is a safe and effective alternative to open surgery in selected cases.