Elbow radiograph in a patient with gout. Note large soft tissue abnormality (arrows) superficial to the olecranon. This represents olecranon bursitis. In addition to gout, it can also be seen in patients with rheumatoid arthritis, or be related to trauma or infection....
Left toe radiograph shows well-marginated erosions with sclerotic margins (arrow) and overhanging edges (arrowheads) at the interphalangeal joint. The findings are consistent with gouty arthritis. Similar changes are seen at the first MTP joint. (Courtesy of Dr. A....
Bilateral hand radiographs in a patient with osteoarthritis. There is moderate joint space loss at the first carpometacarpal (CMC) joints bilaterally (arrows) with subchondral sclerosis and cystic changes. The interphalangeal joints show similar changes. These are...
Acute Pseudogout (Calcium Pyrophosphate Dihydrate Crystals) Polarized light microscopy showing calcium pyrophosphate dihydrate crystals. Note the positive bifringence (blue) of rhomboid-shaped crystals versus the needle-shaped and negatively birefringent (yellow)...
Acute Gout (Monosodium Urate Crystals) Polarized light microscopy showing monosodium urate crystals. Note the negative birefringence (yellow) of needle-shaped crystals versus the rhomboid-shaped and positively birefringent (blue) crystals of crystal pyrophosphate...
