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Rapidly Progressive Tetraparesis with Ossification of the Posterior Longitudinal Ligament (OPLL)

Case Report Ossification of the posterior longitudinal ligament (OPLL) is a common cervical disease that can cause stenosis in the spinal canal and consequent cervical myelopathy, especially in middle-to-high aged Asian men. Typically, patients with cervical OPLL complain of neck pain in their daily lives but lack any significant neurologic symptoms. However, it can cause myelopathy through even minor trauma, such as falls and blunt head injuries, like reported in the following case. A 50-year-old man living in the nursing home due to mental retardation presented with a sudden onset tetraparesis without prior history of injury. Though he had difficulty in moving the right lower extremity for a long time a diagnosis had not been made, and the patient could walk by himself five days before admission. Physical examination showed weakness in all extremities, most significant in the right lower extremity (grade 1/5 by manual muscle testing). It was difficult to appropriately conduct the neurological examination for sensory disturbance due to the mental retardation. His tendon reflexes of bilateral triceps brachii, biceps brachii and brachioradialis muscle were normal and his patellar and Achilles tendon reflexes were slightly diminished. Bladder and rectal dysfunction were not detected. There was no episode of prior infection and serum potassium level was within normal limits. Cerebrospinal fluid examination showed mild cytoalbuminic dissociation, so we had a suspicion of Guillain-Barré syndrome as one of the differential diagnosis. But on Day 11 we found hyperreflexia of his patellar and Achilles tendon, so cervical CT and MRI scans were performed immediately, demonstrating segmental OPLL (C2-C6) and the cervical spinal cord compression at C3/4. The patient received a diagnosis of cervical myelopathy with OPLL and he was transported to another hospital for surgical intervention. However golden time had passed, so he did not receive operative therapy. An accurate and immediate diagnosis for myelopathy from OPLL based on history, physical exam, and plain radiograph, along with CT and MRI findings is very important to assess the development of myelopathy and to make quick decisions regarding a treatment plan.