WKI Sales Training Feb 2014

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GRANT’S DISSECTOR

Anterior cutaneous branches of 4th intercostal nerve:

Lateral branch Medial branch

External intercostal membrane

Sternum

External intercostal muscle

Internal intercostal muscle

Transversus thoracis muscle

Innermost intercostal muscle

Parietal pleura

Lung

Lateral cutaneous branches of 4th intercostal nerve:

Anterior branch Posterior branch

Body of 4th thoracic vertebra

Spinal cord

Spinal ganglion

4th thoracic spinal nerve

Anterior ramus (intercostal nerve)

Posterior ramus

Posterior cutaneous branches of posterior ramus of 4th thoracic nerve:

Lateral branch Medial branch

FIGURE 3.6 Course and distribution of the fourth thoracic spinal nerve.

3. Use an illustration and your dissected specimen to review the origin, course, and branches of the posterior intercostal artery and intercostal nerve. 4. Consult a dermatome chart and compare the der- matome pattern to the distribution of the intercostal nerves. [G 348; L 162; N 159; R 205; C 10]

12. The anterior end of the intercostal space is sup- plied by anterior intercostal branches of the internal thoracic artery . The internal thoracic artery runs a vertical course just lateral to the border of the sternum and crosses the deep sur- faces of the costal cartilages. [G 24; L 167, 168; N 183; R 208; C 148] Dissection Follow-up 1. Replace the internal and external intercostal muscles in their correct anatomical positions. 2. Review the muscles that lie in the intercostal space. Review their actions. Understand how they assist res- piration by elevating and depressing the ribs.

REMOVAL OF THE ANTERIOR THORACIC WALL Dissection Overview

To view the contents of the thoracic cavity, the anterior tho- racic wall must be removed. The goal of this dissection is to remove the thoracic wall with the costal pleura attached to its inner surface. The structures to be removed include the

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