Thorax I: 5.1 & 5.2

5. Surface & Clinical Anatomy
5.1. Identify and describe the significance of the following surface markings:
5.1.1. Jugular (suprasternal) notch

• Concave centre of superior border of manubrium between the clavicular notches.
• Intrathoracic pressure can be measured using a device that engages the soft tissue located above the jugular notch.
• Evaluative test for the aorta. Able to recognise aneurysm, dissecting aneurysm, atherosclerosis and hypertension. To carry out test, place index/middle finger on notch to palpate. No palpable pulse in normal young people. Prominent pulse may indicate uncoiled aorta, arch aneurysm or tortuous blood vessel. Most likely cause of suprasternal pulse in adult is aortic arch aneurysm; in child, coarctation of aorta.
  

5.1.2. Manubrialsternal joint

• Anterior angle formed by junction of manubrium and body of sternum in the form of a secondary cartilaginous joint (symphysis)

5.1.3. Costal margin

• Medial margin formed by false ribs, specifically from 8th to 10th rib

5.1.4. Midclavicular line

• Vertical line crossing through midpoint of clavicle, parallel to anterior median (midsternal) line
• So that doctors performing median sternotomy are able to know where to make an incision

5.1.5. Midaxillary line

• Vertical line running down the surface of the body passing through the apex of the axilla to the axillary fossa, parallel to anterior axillary line

5.1.6. Paravertebral line

• Vertical line corresponding to tips of transverse processes of vertebrae

5.1.7. T4/ T5 vertebral spines

• Nipple line
• Postero lateral thoracotomy

5.2. What are the indications and anatomical basis for the following common surgical approaches to the thorax?
5.2.1. Median sternotomy

Since median sternotomy involves having to divide the sternum in the median plane and then retracted, it is essential that the doctor makes an accurate incision. This can be done by drawing out an imaginary midclavicular line, and since it is parallel to the midsternal line, an accurate incision will be able to be made.

5.2.2. Postero lateral thoracotomy

The posterior aspects of the 5th-7th intercostal spaces are vital sites for performing postero lateral thoracotomy. These intercostal spaces are able to be located by drawing an imaginary line transversely from either the nipple line (4th/5th vertebral spine) or the inferior border of the scapula (7th vertebral spine) respectively.

5.2.3. Locate and draw