[A case of diffuse idiopathic skeletal hyperostosis (DISH) with various neurological complications]

A 71-year-old female presented with a 10-year history of slowly progressive gait disturbance and dorsolumbar pain. Motion of he neck and trunk was severely restricted. She showed decreased sensation of vibration and position in the upper and lower limbs and had Romberg's sign. Hyperesthesia of touch sensation was distributed in a stocking pattern. She showed hyporeflexia and pathological reflexes in lower limbs. Her gait was ataxic and spastic. Laboratory examination of blood and urine revealed no remarkable findings. Radiographic examination revealed ligamentous calcification and ossification along the anterolateral aspect of the vertebral column at several levels, and there was ossification of hte ligament and tendon attachment to the bone at extraspinal sites. The radiographic features were characteristic of diffuse idiopathic skeletal hyperostosis (DISH). Computed tomography at lower thoracic and lumbar vertebral portions showed compression of the spinal cord by ossification of the flavatum ligament. The conduction velocity of tibial nerves and sural nerves were delayed, and the mechanism of the occurrence of peripheral nerve lesions in this patient could be explained by extrinsic compression by heterotopic calcification or some metabolic factor due to DISH.