Response of the dropped head/bent spine syndrome to treatment with intravenous immunoglobulin

Weakness of neck extension causing a dropped head may result from many neuromuscular disorders. One etiology is isolated neck extensor myopathy. A similar focal myopathy of the lower axial muscles may cause the bent spine syndrome, which manifests as flexion of the trunk and inability to stand upright. Combination of both dropped head and bent spine myopathies is uncommon. Inflammation is usually not pronounced in these conditions and response to immunosuppressive treatment is rare. We present an 81-year-old man who developed progressive weakness of neck and trunk extension over several months, with a prominent inflammatory process in the thoracic paraspinal muscles, which responded dramatically to treatment with intravenous immunoglobulin (IVIg). This case, together with other rare reports, suggests that the presence of inflammation in the biopsy of an affected muscle may predict treatment response.