Thoracic myelopathy secondary to multi-level ossification of the ligamentum flavum in an Asian patient

Abstract

Thoracic myelopathy occurs less frequently than lumbar myelopathy. There are several causes of thoracic myelopathy of which ossification of the ligamentum flavum (OLF) is one. OLF has several unique features, arising posteriorly and causing proprioceptive issues first before extending to cause motor and sensory loss. We present a case of a 58-year-old gentleman with a six-month history of progressive lower limb weakness, numbness, back pain and recurrent falls due to OLF. Magnetic resonance and computed tomography imaging revealed extensive thoracic OLF and concomitant facet hypertrophy involving T6-7, T7-8, T9-10, T10-11 and L1-2. Severe central canal stenosis and L1-2 cauda equina root compression were also seen on radiological imaging. The patient developed sphincter disturbance during his admission and had difficulty passing urine. He underwent physiotherapy but was only able to sit and stand with the help of a walking frame at best. He did not regain motor or sensory function in his lower limbs although his back pain improved. Surgical decompression is associated with good neurological outcomes in OLF. Despite this, our patient declined surgery and opted for conservative therapy instead. We wish to highlight a rare case of thoracic myelopathy and the potentially irreversible neurological deterioration that occurs if there is no early surgical intervention.