Step 1 - Dissection of the Thoracic wall

PREPARATION: You should have already skinned the thoracic wall and reflected the pectoralis major muscles.

1. Clean the internal thoracic vessels on either side (about a finger's breadth) of the sternum as shown. Then carefully clean the intercostal spaces reviewing the intercostal muscles and preserving as many of the intercostal nerves, arteries and veins as you can.
   Remember VAN: (vein-artery-nerve) located along the inferior border of each rib.

2. Next, gently push the pleura from the ribs. In many cadavers the pleura is thin and will tear, but try to retain as much as you can to better understand the pleural reflections.

3. Cut each rib (from 2 to 8 or 9) as far posteriorly as possible with rib cutters. The further you can cut them posteriorly the more room you will have to reach inside the thoracic cavity to finish your dissection of the thorax.

4. Cut the sternum at the junction of the first rib and at the xiphisternum, and remove the rib cage as shown.
   IMPORTANT: Leave the costal arch with diaphragm attached.