What is the most likely working diagnosis for a 14-year-old patient who has proximal forearm pain and a positive fat pad sign on X-ray?

The presence of proximal forearm pain combined with a positive fat pad sign on X-ray strongly suggests a radial head fracture. The fat pad sign indicates that there is an effusion in the joint, which often occurs with trauma experienced around the elbow region. In this specific case, the injury likely involves an intra-articular fracture, which is typically associated with a positive fat pad sign.

In adolescents, especially those around the age of 14, radial head fractures can occur due to falls on an outstretched hand or direct trauma. The symptoms of pain and any associated swelling make this diagnosis highly plausible. The diagnosis is further reinforced by the fact that the radial head is located in the proximal forearm, aligning with the patient's reported location of pain.

Other conditions, like a distal radius fracture, generally present with wrist pain and not specifically in the proximal forearm area. An elbow dislocation might show other signs such as a visible deformity or severe instability at the joint, rather than isolated pain in the forearm. A scaphoid fracture would typically present with wrist pain after falling on an outstretched hand and would not account for pain localized to the proximal forearm or a positive fat pad sign. Therefore, given the context and findings,