Between 1955 and 1980 a total of 67 patients (42 female, 25 male) with advanced tuberculosis of the pelvic girdle underwent surgery at the authors' clinic. In 43 patients the sacroiliac joint was affected (in 2 cases bilaterally), in 11 the ischium, in 9 the pubic bone, and in 2 each the ilium and the sacrum. The average of the patients (who included 4 migrant workers) was 44. The youngest patient was 8, the oldest 67 years old. The average interval between the onset of complaints and diagnosis was 4.6 years (minimum 1 month, maximum 20 years). Thirty-eight of the patients had already had treatment for an organic or osteoarticular tuberculosis. Although 24 (35.8%) of the patients were simultaneously suffering from a florid, specific infection localized elsewhere, and abscesses, fistulas, or a combination of these were identified in 40 patients (59.7%), only 17 (25.4%) were in slightly impaired general condition, and in over one-half of the patients, the hourly blood sedimentation rate was normal or only slightly elevated (up to 20 mm n.W.). In 9 cases (13.4%) the only pointers to tuberculosis were the patient's history, clinical and radiological findings, and the subsequent evolution of the disease. In these cases the diagnosis could not be confirmed either by histologic or by bacteriologic study of focal tissue. In 67 patients, 66 osseous foci were removed and in 2 cases merely an abscess (after an average of 2-3 weeks' tuberculostatic therapy), the bone cavities were filled with a mixture of heterogeneous or autogenous spongiosa and tuberculostatics or merely with chemotherapeutic drugs, and primary closure of the wound was performed.(ABSTRACT TRUNCATED AT 250 WORDS)