Ankylosing vertebral hyperostosis (HVA) or diffuse idiopathic skeletal hyperostosis (DISH) is a disease often seen in the middle-aged and elderly, frequently in patients older than 70 years (10.1% in men, 6.8% in women). Enthesal ossifications can occur at any site of tendinous or ligamentous insertion. The spine is commonly involved. The characteristic appearance is the presence of thick bony bridges between vertebral bodies of the right side of thoracic spine. Many authors, especially Fischer and Stecher, have described hyperostosis of the rib at the costo-vertebral articulation. In our study, 52 patients were examined. The physical examination consisted essentially in pulmonary function and measurement of thoracic and spinal mobility. In spite of severe ankylosing vertebral hyperostosis, which evokes important ossification of the costo-vertebral articulation, we couldn't demonstrate any change in pulmonary function.