Fig. 5

A 2-year-old girl with Blau syndrome presenting with swelling of the hands, knees, and ankles. a Frontal radiograph of the right hand demonstrates diffuse periarticular osteopenia, soft tissue swelling around the proximal interphalangeal joints (arrows). No joint space narrowing, erosions or osseous destruction. Similar changes were present in the left hand (not shown). b Lateral radiograph of the right knee demonstrates large suprapatellar joint effusion (arrow) and soft tissue swelling. Similar changes were seen in the left knee (not shown). c Lateral radiograph of the right ankle demonstrates soft tissue swelling along the tendons representing tenosynovitis (arrows). d Axial T1-weighted image with fat suppression after intravenous contrast administration of the right wrist demonstrate thickening and enhancement of the tendon sheaths of all the extensor tendons (arrows) representing tenosynovitis. e follow up frontal radiograph of the right hand of the same patient at the age of 25 years demonstrates typical flexion contracture of the PIP joints of the fourth and fifth digits (arrows). Note that there are no erosions