Kump's Hump

Kump's hump, also known as kump's bump, is named after the radiologist Warren Kump, who described an undulation of the anteromedial aspect of the distal tibial physis.

Kump's hump is the site of first closure of the physis and should not be mistake for a fracture. On MRI, the normal loss of cartilaginous signal intensity of the physis begins at Kump's hump.

Kump's hump can also present a pitfall on MRI. The undulation at this location can simulate physeal closure on T1-weighted images, a phenomenon that is due to partial volume averaging of the physis with the adjacent epiphysis and metaphysis.

References

• Chung T, Jaramillo D. Normal maturing distal tibia and fibula: changes with age at MR imaging. Radiology. 1995 Jan;194(1):227-32.
• Keats TE and Anderson MW. Atlas of Normal Roentgen Variants That May Simulate Disease. 8th edition, page 812; Mosby (2004).
• Kump WL. Vertical fractures of the distal tibial epiphysis. Am J Roentgenol Radium Ther Nucl Med. 1966 Jul;97(3):676-81.