Age / Sex : 10 / M

Chief complaint :

Left elbow medial aspect bony protrusion

What is your diagnosis?

Two weeks later, you can see the final diagonosis with a brief discussion of this case (Please submit only one answer).

Courtesy : Eun Hae Park, Chonbuk National University Hospital

Discussion

Answer:  

Osteonecrosis of trochlea (Trochlear AVN)

Findings:

V shape trochlea, fish tail deformity of trochlea

Differential Diagnosis:

Osteolytic bone tumor

Discussion:

 Rare but important complication after supracondylar humerus fractures.

AVN of the trochlea has a late clinical presentation. The cause of this complication is interruption of the trochlea blood supply.

AVN of the trochlea should be considered in patients with late presentation of pain or loss of motion after treatment of supracondylar humerus fractures.

References:

Avascular Necrosis of Trochlea After Supracondylar Humerus Fractures in Children.Am J Orthop (Belle Mead NJ). 2015 Oct;44(10):E390-3.