[Ossification of ligamentum flavum unmasked by acute paraplegia].

A 30-year-old black man presented sudden-onset paraplegia during a foot-ball match, after a movement of hyperextension of the trunk. Moreover, the patient exhibited an hypoesthesia below the T11 level, with sphincter disturbances. The MRI and the CT-scan showed a stenosis of the spinal canal related to an ossification of hypertrophied ligamenta flava from T10 to T12. Intramedullary abnormal signals on MRI images were compatible with a spinal cord hemorrhage. A laminectomy with removal of abnormal ligamenta flava was carried out, and their endochondral ossification was confirmed by pathological examination. Two months later, the patient was able to walk alone and exhibited a mild spasticity associated to sensory disturbances of lower limbs. Ossification of ligamenta flava is usually observed in Japanese patients, sometimes in Caucasians, more rarely in black people. Its mechanism is unclear except when associated with metabolic or endocrine diseases. The patients usually present with clinical features of chronic spinal cord compression. Our case seems to be the first one disclosed by an acute spinal cord injury on ossified ligamenta flava. In this patient, because of remaining adjacent ossified ligamenta flava and the development on postoperative MRI of an intramedullary cavity, a long-term clinical and radiological follow-up is particularly necessary.