Camptocormia as a clinical manifestation of polymyositis/systemic sclerosis overlap myositis associated with anti-Ku.

Camptocormia, an abnormal truncal flexion posture that occurs while walking or standing, is usually caused by various hypokinetic movement disorders, mainly Parkinson disease. We describe the case of a man with subacute onset of camptocormia. Quadriceps muscle biopsy showed significant rhabdomyolysis, few isolated inflammatory cells and mild expression of type I MHC in few fibers, a pattern usually found in immune-mediated necrotizing myopathies. Myositis was associated with Raynaud's phenomenon, mild sclerodactyly, and anti-Ku antibodies leading to the diagnosis of polymyositis/systemic sclerosis overlap myositis. The posture showed modest improvement in response to treatment.