Final answer:
The elbow region is formed by three joints: the humeroulnar joint, the humeroradial joint, and the proximal radioulnar joint.
Step-by-step explanation:
The elbow region is formed by multiple joints. The primary joint is the humeroulnar joint, which is formed by the articulation between the trochlea of the humerus and the trochlear notch of the ulna. Additionally, there are two other joints associated with the elbow: the humeroradial joint, which is formed by the articulation between the capitulum of the humerus and the head of the radius, and the proximal radioulnar joint, which is formed by the articulation between the radial head and the radial notch of the ulna.