• 2nd-4th decade
  • M=F
  • Intramedullary neoplasm
  • Lobules of benign hyaline cartilage
  • Second most common benign chondral lesion after osteochondroma
  • Tubular bones of hands and feet
  • Asymptomatic, present when size increases or when pathological fracture occurs
  • Proximal phalanges in most cases, then metacarpals, middle phalanges
  • Less common in bones of feet, femur, tibia and humerus 
  • Enchondroma protuberans – eccentric enchondroma with extra-osseous component, covered by thin shell of intact cortical bone. Fingers or toes. 
  • Centrally in phalanges and metacarpals
  • Metaphyseal or diaphyseal 
  • Eccentric and often solitary
  • Well circumscribed, lobular or oval lytic lesions 
  • May expand the cortex
  • 10 to 50 mm in size
  • Chondral-type mineralization may be seen
  • MRI – small septa within lesion shows mild enhancement. 
Read more

Melamud, Kira, et al. “Diagnostic imaging of benign and malignant osseous tumors of the fingers.” Radiographics 34.7 (2014): 1954-1967.

Murphey, Mark D., et al. “Enchondroma versus chondrosarcoma in the appendicular skeleton: differentiating features.” Radiographics 18.5 (1998): 1213-1237.