The median, ulnar, and radial nerves are all located in the upper extremity, and their specific locations differ. 1. Median nerve: In the upper arm, the median nerve accompanies the brachial artery, and in the elbow fossa, the median nerve is located in the deep surface of the tendon membrane of the biceps brachii muscle. Injury to the median nerve can cause sensory and movement disorders. 2. ulnar nerve: the ulnar nerve originates from the medial bundle of the brachial plexus, along the medial side of the brachial artery, and travels downward from the ulnar nerve groove to the dorsum of the hand, forming the dorsal branch of the hand. 3. Radial Nerve: The radial nerve is the posterior bundle of the brachial plexus and is located in the axilla behind the axillary artery, dividing into two branches, superficial and deep, in front of the lateral epicondyle of the humerus. Median nerve, ulnar nerve, radial nerve belongs to the human upper limb nerves, patients with abnormalities in the above areas should go to the hospital in time for examination and treatment under the guidance of the doctor after clarifying the cause of the disease.