LAUSR

BACKGROUND Symptomatic calcification of the ligamentum flavum (CLF) is common in the cervical spine, but very rare in the thoracic spine. Rapidly progressing CLF in the thoracic spine has not been reported in the literature. CASE DESCRIPTION A 76-year-old Asian male experienced back pain after a fall and was diagnosed with osteoporotic vertebral fractures (OVFs) at T11 and L1. He was treated conservatively because of the lack of neurologic deficits. Nine months after the initial visit, he complained of progressive incomplete paraplegia. Magnetic resonance imaging and computed tomography of the thoracic spine showed CLF at T11-T12 severely compressing the spinal cord. This finding had not been seen on imaging studies at the initial visit. The patient underwent surgical resection of CLF and posterior instrumented spine fusion. Symptoms of muscle weakness recovered postoperatively. CONCLUSIONS In this case, sequential imaging studies with a 9-month interval showed evidence of rapidly progressing thoracic CLF. The preceding OVF may have triggered the development of CLF.