The exact location of the left ulna is on the inside of the left forearm, with the radius on the outside. There are two long bones in the forearm of the human body, and there is a difference between long and short. The ulna is the long one, on the side of the little finger, and can play a stabilizing role for the forearm. The other, slightly shorter one is the radius. The ulnar humerus can be felt on the surface of the body on the back of the elbow joint, and the ulnar tuberosity can be felt on the inside of the wrist joint. The ulnar stem can also be palpated in thinner people. The ulna is the main bone component of the forearm. The forearm is generally divided into two parts: the radius and the ulna. The ulna is the medial shaft bone of the forearm and the radius is the rotating bone and supports the ulna. The shafts of the ulna and radius work together to support the ulna during flexion, extension, or rotation of the forearm. If there is any discomfort in the forearm, it is recommended to consult a doctor in time, complete the relevant examinations, clarify the cause of the disease and carry out targeted treatment under the guidance of a professional doctor, so as to avoid delaying the condition.