Kashin-Beck disease

Kashin-Beck disease (KBD) is a rare chronic condition, comprising an osteochondropathy with a concurrent necrosis of the joints.

Epidemiology

The disease has traditionally been endemic to areas of Tibet, China, North Korea, and Siberian Russia, and is usually diagnosed in pre-teenage children.

Clinical presentation

The presentation is similar to rheumatoid arthritis. Extraskeletal disease is not seen.

Pathology

Pathologically, the lack of dietary selenium is important. The lack of selenium affects the functioning of antioxidants such that osteocartilaginous necrosis ensues. Additional implicated factors with good supporting evidence are dietary deficiency of iodine, mycotoxin-secreting fungi, and polluted water sources .

Radiographic features

In untreated cases, there will be evidence of the destructive deforming pathology in plain radiographs of joints of the shoulder, elbow, hand, hip, knee, and ankle. Signs of the disease apparent on plain radiograph of the hands include:

• articular surface depressions
• carpal crowding
• subchondral bony deformity in the proximal end of phalanges with or without bony sclerosis
• fragmentation of proximal phalanges
• bony enlargement of the phalanges