Low back pain in Paget's disease of bone.

Clinical and laboratory evaluation with bone scan, radiography, and computed tomography were performed on 25 patients with severe Paget's disease of bone and low back pain. Back pain was classified as caused by Paget's disease in only three patients. The remaining 22 patients had coexistent Paget's disease and osteoarthritis. There was difficulty separating the cause of back pain in those patients with coexistent Paget's disease and osteoarthritis, even when the diseases were present at different levels of the spine. The pathogenesis of Paget's disease appears to precipitate osteoarthritis and several low back syndromes. Suppressive therapy with disodium etidronate (EHDP) for Paget's disease was of benefit in eight of 22 patients (36%) with identifiable osteoarthritis. It is suggested that EHDP and perhaps other suppressive agents for Paget's disease receive limited use in patients with back pain unless a defined pagetic lesion appears related to the clinical syndrome in the absence of identifiable osteoarthritis.