Continuing with the thought of highlighting structure and function I will take some time to speak about the second rib. The second rib is similarly shaped to the first rib but it is noticeably larger.
The muscles that attach to the second rib are: posterior scalene, serratus posterior superior, levator costae, iliocostalis cervicis, iliocostalis thoracis, and serratus anterior. There are also attachments of the internal and external intercostal muscles (this is important as simple respiration can be used to help re-articulate a displaced rib if it is appropriate). Along with the muscles attached to the second rib, the internal surface of the second rib also acts as an anchor for the pleura of the lungs (this is one of the ways the second rib shows a relationship with lung function).
The nerves associated with the second rib are: the second thoracic nerve (with the anterior/intercostal branch and the posterior branch), and the second thoracic sympathetic ganglion (with pulmonary, cardiac, and aortic branches). There are also branches from T2 that go to the ligaments, vertebrae, spinal cord, and meninges at T2. It is important to note the relationship of all ribs with the sympathetic chain ganglion as sympathetic symptomatology/expression is often related to altered positioning of the rib head.
The general lesion pattern of the second rib is to be caught upwards and backwards due to the action of the posterior scalene as well as levator costae. Considering the general lesion the general correction would be forwards and downwards. I don’t want to give away everything I am learning at the CAO here however, if you are a student of the CAO you should be able to make some connections here.
As I outlined the nervous connections and, more importantly, the soft tissue connections earlier the commonly related issues should not be terribly hard to grasp. A lesion of the second rib will generally express through the pleura, the lungs, the bronchi, and the second intercostal nerve. The names of conditions that are often associated with a lesion of the second rib are bronchitis, broncho-pneumonia, pleurisy, and tuberculosis. A lesion of the second rib can either be causative or reflexive in the aforementioned conditions. I think it is fair to say that terming a second rib lesion as causative in these conditions is primarily related to the fact that the nervous transmission to the lung and pleura would be highly sympathetic if a second rib lesion is present as well as the mechanical strain placed on the pleura with the associated alteration in pressure dynamics inside the thorax. Due to the increased sympathetic tone to the area, associated vasomotion would be altered leading to increased fluid in to the area and decreased fluid out. There will be congestion of the area and any toxicity, bacterial, or viral pathogens will have a wonderful area to set up shop. They will have the environment they need to thrive and the conditions they create will happen in relation to the lesion of the second rib.
There are also connections to conditions of the head and neck from a lesion of the second rib through the sympathetic chain ganglion from T1-T4 governing the sympathetic tone to those areas. There are also connections to heart issues through the sympathetic tone coming from segments T1-T5 governing the sympathetic tone to the heart.
To make this as clear as possible I will say that a second rib lesion can set the stage for the sympathetic nervous system to go in to overdrive in the head, neck, heart, and lungs allowing for opportunistic pathogens to thrive. Reducing the sympathetic drive to the area will create better balance related to the parasympathetic tone so that the body can effectively mobilize its natural healing abilities. The other consideration is the mechanical aspect of ensuring that all pathways of nerves, arteries, veins, and lymphatic vessels are clear to allow nature to do its work.