The dropped head plus syndrome: quantitation of response to corticosteroids.

Severe neck extensor weakness causes the dropped head syndrome and is a disabling symptom of many specific disorders. When a diagnosis cannot be established, it has been considered a manifestation of a restricted noninflammatory myopathy. A 44-year-old man presenting with dropped head and subsequent severe limb weakness did not respond to a first trial of corticosteroids but responded well to a subsequent prolonged trial of azathioprine followed by prednisone. The decision to persist with the second trial of treatment was prompted by documented sequential increases in lean body and muscle mass, and an improvement in the quantitative myometry score which preceded clinically obvious improvement. While mechanical damage to overstretched cervical paraspinal muscles is thought to preclude a response to treatment, cases of unexplained dropped head syndrome may merit consideration of prolonged immunosuppressant treatment.