Rib and Costal Cartilage Identification- Pleural Reflections- Position and Enlargement of the Heart

Rib and Costal Cartilage Identification

When one is examining the chest from in front, the sternal angle is an important landmark. Its position can easily be felt and often be seen by the presence of a transverse ridge. The finger moved to the right or to the left passes directly onto the second costal cartilage and then the 2nd rib. All other ribs can be counted from this point. The 12th rib can usually be felt from behind, but in some obese persons this may prove difficult

Pleural Reflections

It is hardly necessary to emphasize the importance of knowing the surface markings of thepleural reflections and the lobes of the lungs. When listening to the breath sounds of the respiratory tract, it should be possible to have a mental image of the structures that lie beneath the stethoscope. The cervical dome of the pleura and the apex of the lungs extend up into the neck so that at their highest point they lie about 1 in. (2.5 cm) above the clavicle. Consequently, they are vulnerable to stab wounds in the root of the neck or to damage by an anesthetist’s needle when a nerve block of the lower trunk of the brachial plexus is being performed.

Remember also that the lower limit of the pleural reflection, as seen from the back, may be damaged during a nephrectomy. The pleura crosses the 12th rib and may be damaged during removal of the kidney through an incision in the loin

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Position and Enlargement of the Heart

The surface markings of the heart and the position of the apex beat may enable a physician to determine whether the heart has shifted its position in relation to the chest wall or whether the heart is enlarged by disease. The apex beat can often be seen and almost always can be felt. The position of the margins of the heart can be determined by percussion.

The Thoracic Outlet Syndrome- Movements of the Ribs and Costal Cartilages

The Thoracic Outlet Syndrome

The brachial plexus of nerves (C5, 6, 7, and 8 and T1) and the subclavian artery and vein are closely related to the upper surface of the 1st rib and the clavicle as they enter the upper limb it is here that the nerves or blood vessels may be compressed between the bones. Most of the symptoms are caused by pressure on the lower trunk of the plexus producing pain down the medial side of the forearm and hand and wasting of the small muscles of the hand. Pressure on the blood vessels may compromise the circulation of the upper limb.

Movements of the Ribs and Costal Cartilages

The 1st ribs and their costal cartilages are fixed to the manubrium and are immobile. The raising and lowering of the ribs during respiration are accompanied by movements in both the joints of the head and the tubercle, permitting the neck of each rib to rotate around its own axis.