week 9 sem 2

Question 1

Diameters of the thorax

Answer 1

All dimensions of the thoracic cage
increase with each inspiration
(inward breath)
* Vertical diameter increased by
descent of the diaphragm
* Antero-posterior diameter
increased by movement of the
sternum and anterior parts of ribs
* Lateral diameter increased by
movement of the lateral parts of the
ribs

Question 2

Movement of the ribs. pump handle, bucket handle

Answer 2

• Pump handle
• Upper ribs – 2-5
• Increases A-P diameter
• Movement axis along neck of rib
• Bucket handle
• Lower ribs – 8-10
• Increases lateral diameter
• Movement axis through costovertebral
  and sternocostal joints

Question 3

diaphragm is the prime mover for?

Answer 3

inspiration

Question 4

Apertures of the Diaphragm

Answer 4

1. abdominal aorta @T12
   behind diaphragm, not afftected by diaphragm contractions
   2.Oesophagus – @T10
   * Through the muscle of the
   diaphragm, Sealed closed by diaphragm contraction
2. Inferior vena cava – @T8
   * Through the central tendon
   * Opened by diaphragm contraction

Question 5

intercosta muscles during breathing

Answer 5

Stiffen the space between the ribs,
role in breathing and in posture

Question 6

• Accessory muscles of inspiration

Answer 6

muscles that help produce forced inspiration

eg muscles associated with the upper limb: serratus anterior, pectoralis major and minor, sternocleidomastoid, Scalenes group, Serratus posterior superior

Question 7

Expiratory muscles

Answer 7

Largely passive in awake humans
* Diaphragm contracts eccentrically for a short period at the commencement of expiration to slow expiratory rate
Forced expiration:
* Abdominal muscles
* Any other muscle that can pull the ribs
down- eg serratus posterior inferior,
quadratus lumborum