Imaging of Drug-Related Changes in the Musculoskeletal System

Abstract

About 10% of bone can be undergoing turnover at any given time, and multiple factors, including diet, disease, and medication, affect this delicate osseous homeostatic balance. New medications are introduced continuously, and there is an increasing prevalence of polypharmacy. Familiarity with the osseous side effects of various medications enables radiologists to play an important role in recognizing these side effects and alerting clinicians to correct diagnoses. Bone is composed of cellular and extracellular components. The extracellular components include organic matrix, osteoid tissue, and inorganic crystalline material that contains calcium phosphate and hydroxyapatite. The cellular components include osteoblasts, which synthesize bone; osteoclasts, which are involved in bone resorption; and osteocytes, which are relatively insert cells. Bone growth depends on rates of resorption; bone mineralization; dietary intake; intestinal absorption of vitamin D, calcium, and phosphorus; and humoral factors such as growth hormone from the pituitary gland, parathormone from the parathyroid gland, and fibroblast growth factor-23 produced by osteoclasts. Medications can affect, directly or indirectly, these osseous components, causing a change in the extracellular or cellular makeup of bone or hormonal components affecting the skeletal system.