Thirteen patients with isolated pain and swelling of a sterno-clavicular clavicular joint have been reviewed. Three groups were identified. Group 1 comprised four patients, all of whom had a short history of less than six weeks and suffered a pyarthrosis or malignant disease; group 2, four patients who were shown to have features of condensing osteitis of the clavicle (Cone et al, 1983); and group 3, five patients, had degenerative arthritis of a sterno-clavicular joint. The only difference between groups 2 and 3 were that patients in group 3 had a rather longer history, both articular surfaces were involved and showed a possible increase in the incidence of degenerative joint disease elsewhere. It is suggested that condensing osteitis is but a part of a spectrum of degenerative disease of the sterno-clavicular joints, akin to discogenic vertebral body sclerosis (McCarthy & Dorfman, 1982).