A grave symptom of a brain injury. This includes clenching of fists, flexion of arms in towards the body and hyperextension of legs. When the pressure inside of the cranium (intracranial pressure) increases more and more pressure is placed upon the top of the spinal cord, through the foreman magnum. This pressure placed upon the brain and spinal cord is very harmful to life and requires immediate medical attention. Decorticate posturing yields a GCS score of 3. While this is very dangerous it is usually a better sign than decerebrate posturing.