Spontaneous Spinal Epidural Hematoma with Lumbar Facet Joint Destruction Mimicking Pigmented Villonodular Synovitis

Abstract

Background: Spontaneous spinal epidural hematoma (SSEH) is a spinal emergency that requires early diagnosis and decompression surgery. Here, we report a case of SSEH that was difficult to differentiate from pigmented villonodular synovitis (PVS) because of combined facet joint destruction and that required gross total resection, a procedure not typically indicated for SSEH.

Case description: A 58-year-old woman complained of sudden-onset walk disturbance after backache without any traumatic episode. Physical examination revealed motor paralysis in the leg. Moreover, extensive destruction of the L4/5 right facet joint and an epidural mass continuing from the facet was observed. The epidural mass showed heterogeneous intensity in magnetic resonance imaging, suggesting different stages of bleeding. These hemorrhagic changes combined with the facet joint destruction suggested PVS, and preoperative and intraoperative pathologic examinations could not rule out PVS. After surgical treatment of PVS, the lesion in the articular process was resected and decompression was performed. The pathologic diagnosis was hematoma with bone necrosis in the articular process, without neoplastic finding suggesting PVS.

Conclusions: SSEH could be combined with facet joint destruction composed of bone necrosis. Awareness of SSEH with facet joint destruction can facilitate early diagnosis and appropriate surgical treatment.

Keywords: Facet joint destruction; Intracapsular bleeding; Necrotic bone; Pigmented villonodular synovitis; Spontaneous spinal epidural hematoma.