Exuberant ossifications and calcifications of bone and of entheses (the site of attachment of ligament or muscle to bone) is the characteristic feature of Proliferative Bone Disease, examples of which are Diffuse Idiopathic Skeletal Hyperostosis (DISH), Hypertrophic Osteoarthropathy (HOA), Osteoarthritis (OA), Seronegative spondyloarthropathies - Ankylosing Spondylitis (AS), Psoriatic arthritis (PsA), SAPHO (Synovitis, Acne, Pustulosis, Hyperostosis, Osteomyelitis) and those associated with endocrine disorders - Acromegaly, Thyroid disorders and Hypoparathyroidism.
