Ultrasonography changes in hand OA

Image A shows definite, small osteophyte at the interphalangeal joint (arrow) without any erosion or synovitis. Image B shows larger osteophytes (short arrows) without erosion or synovitis. Image C shows large osteophyte with effusion but without any synovial hypertrophy or Doppler signal. This is in contrast to rheumatoid arthritis, where there is synovial hypertrophy and Doppler signal.