2:4 Muscles of Expiration: Thorax, Back, and Upper Limb

Question 1

Mnemonic for the Muscles of the Thorax, Back, and Upper Limb (Expiration):

Answer 1

In The Summer Sweat Lasts

Question 2

Muscles of the Thorax, Back, and Upper Limb (Expiration) - 5:

Answer 2

1. Internal Intercostal (interosseous portion)
2. Transversus Thoracis
3. Subcostals
4. Serratus Posterior Inferior
5. Latissimus Dorsi

Question 3

Internal Intercostals (interosseous portion) O, I, A?

Answer 3

Origin: superior margin of each rib (1-12)

Insertion: run up and medially insert into inferior surface of the rib above

Action: Depresses ribs 1-11

Question 4

Transverse Thoracis O, I, A?

Answer 4

Origin: lower third of sternum

Insertion: inner chondral surface of ribs 2-6

Action: decreases the volume of the thoracic cavity

Question 5

Subcostals (describe) and O, I, A?

Answer 5

-Vary in number; generally course parallel to the internal intercostal muscles

Origin: inner thorax, inner surface of the rib near angle

Insertion: inner surface of second or third rib below

Action: depresses thorax

Question 6

Serratus Posterior Inferior O, I, A?

Answer 6

Origin: spinous processes of T11-T12 and L1-L3

Insertion: lower margin of lower five ribs

Action: pull the rib cage down

Question 7

Latissimus Dorsi (describe) and O, I, A?

Answer 7

-Broad Triangular Muscle

Origin: lumbar, sacral, and lower thoracic vertebrae

Insertion: humerus

Action: stabilizes posterior abdominal wall for expiration