[Sacro-iliac involvement in he course of Paget disease. Report of 6 cases].

Objectives: Determine the characteristic features of sacroiliac lesions observed in patients with Paget's disease.
Patients and Methods: A retrospective analysis of the hospital files of 87 patients cared for over a period of 12 years was performed. Six patients, 4 women and 2 men, mean age 79 years, were retained for study. In 4 patients one or both sacroiliac joints were involved with complete fusion of the sacral and iliac bones, confirmed by CT-scan in 3. In the 2 other patients, only one border was involved. Scintigraphy showed polyostotic Paget's disease in 3 cases with pelvic localization in the 3 others. Ankylosing spondylarthritis (B27+) was associated in 1 case and in 2 joint chondrocalcinosis without a calcium rim was visualized at the sacroiliac joint. Sacroiliac fusion was related either to new bone forming a bridge in front of the articular space or destruction of the joint cartilage with pagetic fusion.
Conclusion: Sacroiliac involvement in Paget's disease leads to joint fusion by cartilaginous destruction and should suggest possible ankylosing spondylarthritis, ankylosing vertebral hyperostosis, or joint chondrocalcinosis.