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.
giving out or weakness of the knees can have different causes. These can include problems outside the knee joint itself (weak muscles for example) or inside the knee (torn ligaments or cartilage). See an orthopaedic surgeon to address your individual problem.