Ultrasound is gaining ground over conventional imaging methods in the assessment of musculoskeletal changes in osteoarthritis. Systematic ultrasound scanning following established guidelines enables the detection of even minimal and early abnormalities of cartilage, synovial tissue and subchondral bone. Thus far, ultrasound has shown to be extremely sensitive in the detection of soft tissue changes in knee osteoarthritis, including synovial proliferation and synovial fluid. Such abnormalities are correlated with symptomatic flares and have associated prognostic implications. Although there has been some progression, there is still a lack of standardization and validation over the definition and scoring of ultrasound signs that are thought to reflect structural damage affecting different joint structures. Meanwhile, exciting developments are expanding the applications of ultrasound in the musculoskeletal field; the application of technologies such as sonoelastography, imaging coupling, 3D ultrasound and ultrasound contrast agents in the field of osteoarthritis is expected to improve not only healthcare-related aspects but also our current understanding of the pathophysiology of the disease.