A 13-year-old male is brought to the ER after injuring his forearm. He fell onto his palm and noted pain and a deformity in his forearm. Examination revealed normal vital signs and findings limited to his left arm. His clavicle, shoulder, humerus, and hand were non-tender. He was reluctant to move his shoulder since his forearm was in a splint and sling. There was an obvious angulation at the mid-forearm. He could move all his fingers. No circulatory or sensory deficits were detected.X-rays of his forearm are obtained. The most likely diagnosis is?