The radioulnar joint is a pivotal joint in the forearm that connects the radius and ulna, the two long bones of the arm. This joint allows for the rotation of the forearm, enabling movements such as turning the palm up (supination) and turning it down (pronation). There are two main types of radioulnar joints: the proximal radioulnar joint, located near the elbow, and the distal radioulnar joint, located near the wrist. Both joints work together to facilitate smooth and coordinated arm movements, playing a crucial role in daily activities like writing and using tools.