What is this? Bone cyst

Case presentation

A 5-year-old male presents with left arm pain after a fall. He was playing soccer when he fell and landed on his left shoulder. He immediately complained of upper arm pain. His examination is significant for focal tenderness to the proximal left humerus with decreased range of motion when he attempts to raise the arm. There is mild edema. He is grossly neurovascularly intact. Imaging is obtained and a proximal humeral fracture is noted. However, the fracture is through a mildly expansile radiolucent lesion.

Prior to this trauma, the child had no symptoms, including fever, pain, or edema of the extremity. He also has no chronic medical conditions.

Imaging considerations