The changed pattern of bone and joint tuberculosis in Norway.

The reduced incidence of bone and joint tuberculosis in Western countries and the change in the age groups afflicted are well known facts. In addition, there are other less conspicuous changes: multiple lesions and involvement of the spine and sacro-iliac joints are rarer than before, while trochanteric involvement is becoming more frequent. In spinal cases the lesion is now more often localized to the dorsal region. All these changes may be due to the change in age distribution of the patients.