Thoracic Wall

Question 1

External intercostals origin/insertion

Answer 1

Lower margin of rib to upper margin of next lower rib (courses obliquely forward and downward from costal tubercle to chondro-osseous junction)

Question 2

Intercostals innervation

Answer 2

1-11th intercostal nn.

Question 3

External intercostals action

Answer 3

Raises ribs during inspiration;support intercostal spaces

Question 4

Innermost and internal intercostals action

Answer 4

Lowers ribs in expiration; supports intercostal space

Question 5

Subcostal mm. Origin/insertion

Answer 5

Lower margin of lower ribs to inner surface of ribs two to three ribs below

Question 6

Subcostal mm. Innervation

Answer 6

Adjacent intercostal nn.

Question 7

Subcostal mm. Action

Answer 7

Lowers ribs in expiration

Question 8

Transversus thoracis origin

Answer 8

Sternum and xiphoid process

Question 9

Transverse thoracis m. Insertion

Answer 9

2nd to 6th ribs (costal cartilage, inner surface)

Question 10

Transversus thoracis innervation

Answer 10

2nd to 6th intercostal nn.

Question 11

Transversus thoracis action

Answer 11

Weakly lowers ribs (expiration)

Question 12

innermost and internal intercostal origin/insertion

Answer 12

Lower margin of rib to upper margin of next lower rib (courses obliquely forward and upward from costal angle to sternum)