Imaging in Foot and Ankle Arthritis.

The foot and ankle are commonly involved in a range of arthritides that affect the joints, bones, and soft tissues. Accurate plain film interpretation can often aid the diagnosis and monitor disease progression and treatment response. Ultrasound and MRI afford superior depiction of the soft tissues, and advances over recent years have centered on early detection of synovitis, enabling earlier diagnosis and treatment. Advantages and disadvantages of the imaging techniques of radiography, multidetector computed tomography, ultrasound, and MRI are discussed, as is optimization of these modalities for the assessment of the anatomically complex joints of the foot and ankle. Diagnostic features enabling differentiation between rheumatoid arthritis, seronegative spondyloarthropathies, osteoarthritis, gout, crystal deposition disease, pigmented villonodular synovitis, Charcot arthropathy, septic arthritis, synovial osteochondromatosis, hemophilia, and reflex sympathetic dystrophy are also reviewed.