[Sterno-costo-clavicular hyperostosis: a hitherto undescribed entity (author's transl)].

Persistent pulling pain in the sternum, clavicles and both first ribs, especially during cold and wet weather, necessitated medical investigations and treatment in 3 patients. Externally a cylindrical or spindle-shaped swelling of the clavicles was noticeable and two patients had signs of superior caval obstruction in addition. X-rays showed hyperostosis of the sternal and middle part of the clavicle, synostosis of the sternoclavicular joints with involvement of the two first ribs as well as a thickening and increase in breadth of the sternum. In one patient there were additional swellings of the first to fourth ribs bilaterally. During the period of observation there was no radiological progression of the bone disease. Apart from a consistently raised erythrocyte sedimentation rate blood chemistry was normal. The sterno-costo-clavicular hyperostosis led to bilateral occlusion of the subclavian veins with resulting upper venous congestion in two patients. Histology of the biopsy samples showed a characteristic hyperostotic spongiosclerosis in all three cases. The cause of this sterno-costo-clavicular hyperostosis is unknown. Clinical, radiological and histological findings indicate that it is a uniform disease which has not previously been described.