The ULNA is the longest forearm bone, measuring approximately 10 inches in length. It is located on the medial side of the forearm and runs from the elbow to the wrist. It is the larger of the two forearm bones, with the other being the radius. The ULNA is responsible for providing stability to the elbow joint and helps to support the weight of the arm. It also plays a role in the movement of the wrist and fingers.