damage to the upper trunk of the brachial plexus (C5–C6 roots), more often occurring in birth trauma, less often in shoulder injuries in adults. It is manifested by weakness or paralysis of the muscles of the shoulder and upper arm, which leads to a characteristic position of the hand of the “waiter’s pose” type: the limb hangs along the body, turned inward, the forearm is straightened and pronated. Treatment includes physiotherapy, limb fixation, and in case of severe injuries, surgical repair of nerves.