Fig. 17
From: Pseudotumoural soft tissue lesions of the hand and wrist: a pictorial review
Examples of pseudomasses due to metabolic diseases. a Clinical picture of tophaceous gout. Peri-articular soft-tissue swelling best seen at the proximal interphalangeal joint of the third finger. b Corresponding plain radiograph showing soft-tissue swelling and adjacent periosteal new bone formation (arrow). c Ultrasound of another patient with tophaceous gout at the metacarpophalangeal joint of the thumb, showing a hypoechoic mass with intralesional reflections with retro-acoustic shadowing due to monosodium urate crystal deposition (arrows). d Pseudogout (hydroxyapatite deposition disease) in another patient. Plain radiograph showing linear and amorphous calcifications at the joint capsule of the distal interphalangeal joint of the index (arrows)