The arm can not be lifted up, there are three main reasons: 1. is due to the arm part of the bones, muscles, tendons, ligaments and other soft tissues have damage, in the uplift will appear obvious pain, so manifested as can not be lifted up. 2, is due to the arm position of the soft tissue after the injury, inflammation in the absorption process will lead to the gradual emergence of the soft tissue around the adhesion, in the lift the arm when the adhesion tissue will pull to the muscle. 3, is due to the nerves innervating the arm damage, such as the brachial plexus nerve damage can not innervate the muscles, so the muscles are affected. When lifting the arm, the adherent tissue will pull the muscle, resulting in lifting affected. 3, is due to the damage of the nerves innervating the arm, such as brachial plexus nerve damage can not innervate the muscles of the arm, so the muscles can not be contracted, and the muscles are weak when lifting, so there is a lifting up situation.