Final answer:
The double outer ridges of the capitulum and trochlea are related to bones, specifically the elbow joint's bone articulations, and are not ligaments, tendons, or muscles.
Step-by-step explanation:
The double outer ridges of the capitulum and trochlea refer to structures related to bones rather than ligaments, tendons, or muscles. These structures are part of the elbow joint, which is comprised of the bone articulations between the trochlea of the humerus and the trochlear notch of the ulna, as well as between the capitulum of the humerus and the head of the radius. In this context, the capitulum and trochlea are bone features that interact with the forearm bones to facilitate movement.