The initial site of bone lesions in Paget's disease. A review of two hundred cases.

We retrospectively evaluated the initial site of bone lesions in 200 patients with Paget's disease. There were 117 males and 83 females. Mean follow-up was 13 years in 98 patients. The initial site can be determined accurately only if less than one third of the bone is involved. Paget's disease usually begins in the cancellous bone of an epiphysis or metaphysis. A diaphysis is the first site involved in some instances, and the anterior subperiosteal area of the proximal half of the tibia in a very small number of cases. The distribution of initial pagetic lesions in our series is reported for each of the main bones. Lesions usually arose in the proximal ends of long bones, which are richly vascularized but contain no hematopoietic marrow in adults. This suggests that the distribution of pagetic lesions may be more closely dependent on local circulatory conditions than on the presence of hematopoietic marrow, which is, however, the only source of osteoclasts.