Presentation
Fall onto the outstretched hands.
Patient Data
Comparison between a normal elbow (left picture) and an elbow with joint effusion (right picture) on lateral radiographs.
Joint effusion was noted on the left elbow. No joint effusion was noted on the right elbow. No fractures were seen.
Case Discussion
Elbow joint effusion in the setting of trauma often indicates an occult fracture. In adults, most commonly a radial head fracture should be suspected. In children, a supracondylar fracture is more likely.
On a normal elbow joint, the anterior fat pad should lie in the coronoid fossa and be mostly parallel to the distal humerus, and the posterior fat pad should not be visible.
Elbow joint effusion can be recognized by elevation of the anterior fat pad (sail sign) and/or visualization of the posterior fat pad (posterior fat pad sign).
In the present case, even though no fractures were seen, given the clinical presentation and the elbow joint effusion, the left elbow was treated as a Gartland type 1 supracondylar fracture.