In order to comprehend the condition of vertebral osteophytosis, vertebral osteoarthritis and DISH (diffuse idiopathic skeletal hyperostosis) with respect to diagnosis and aetiology, the vertebral and peripheral (appendicular) frequency and distribution pattern of degenerative joint changes of 176 rather affluent citizens were analysed from the late medieval city of Dordrecht in Holland. Patterns of frequencies with respect to age and sex were found to be similar essentially to those of a present-day Dutch suburban village population. Frequencies for vertebral osteophytosis were twice those for vertebral osteoarthritis, and both increased with age in both sexes. The individual pattern of vertebral osteophytosis and vertebral osteoarthritis seems to indicate that each disorder possesses its own progressive identity. From the distribution pattern and frequency of peripheral osteoarthritis it was concluded, with respect to the vulnerability of developing this complication under physically moderate life conditions, that causal factors for vertebral osteophytosis are less important than those for vertebral osteoarthritis. Osteoarthritis presented itself as a systemic disorder, affecting synovial joints in general. Finally it was appreciated that, with increasing age, bony outgrowths from joint degeneration become anatomically masked by para-articular ossifications from DISH.