Eventually, the bronchi become known as bronchioles â the smallest air tubes in the lungs. This system of air tubes can be thought of as an upside down tree, with the trachea being the main trunk and the bronchi and bronchioles being the branches. The medical term for all the air tubes is 'the respiratory tract'.
An injury to the vertebrae or discs in your neck can cause pain, numbness, or weakness in your shoulder, arm, wrist, or hand because the nerves that extend out from between the neck provide sensation and allow for movement in these areas.
The following are common causes of weakness: A problem in your brain, nerves, or muscles. A condition such as dehydration, a heart problem, infection, or pregnancy. A mental condition, such as anxiety or depression. A drug such as steroids, heart medicine, or muscle relaxants.