Ankle and toe weakness caused by calcified ligamentum flavum cyst: A case report

Figure 1 Plain radiographs of the lumbar spine. A: Lumbar spine anteroposterior X-ray; B: Lumbar spine lateral flexion X-ray showing degenerative changes and spondylolisthesis L4 on L5.

Figure 2 Preoperative magnetic resonance imaging of the lumbar spine. A: Sagittal T2-weighted magnetic resonance imaging (MRI) showing a mass lesion with a hypointense signal at the L4-5 level (arrow); B: Sagittal fat-suppressed T2-weighted MRI showing a mass lesion with a hypointense signal at the L4-5 level (arrow); C: Axial T2-weighted MRI of the corresponding section showing left side dural sac compression by a mass (arrow).

Figure 3 Computed tomography scans of the lumbar spine. A: Sagittal computed tomography (CT) scan showing a calcified mass at the L4-5 level (arrow); B: Axial CT scan showing a calcified mass at the left side of the L4-5 level (arrow).

Figure 4 Intraoperative clinical photographs of the excised calcified cyst. A firm, brown-colored, nodule-like mass originating from the ventral surface of the left side ligametum flavum was found. A: Ventral surface of the excised ligamentum flavum; B: Cross-section of the excised calcified cyst.

Figure 5 Microscopic images of the excised calcified cyst. A: Low magnification (× 8) image showing a cyst in the ventral surface of ligamentum flavum with dark purple-colored calcified material in the cyst (arrow); B: Higher magnification (× 20) image showing no identifiable epithelial cell lining.