Radiographs of selected peripheral entheseal regions from 32 patients with axial diffuse idiopathic skeletal hyperostosis (DISH) were examined for the presence of new bone formation. The prevalence of entheseal new bone in the various regions was as follows: 98% of tibial spines, 91% of posterior heel regions and about 80% of superior patella, olecranon and inferior heel regions. The new bone showed characteristic solid well defined cortical margins without features of inflammatory change. We suggest that further attention to these readily accessible and easily interpretable peripheral entheseal regions, particularly the posterior heel, may be useful to extend the diagnostic criteria of DISH.