PRC Breathing Mechanics & Diaphragm Function 2

Question 1

In the Postural Restoration Institute (PRI) model, the right hemidiaphragm is considered more dominant than the left primarily because of its anatomical relationship with which structure?

Accepted Answer

The liver providing a stable base

Answer

The liver sits beneath the right hemidiaphragm, providing a solid dome-shaped base that makes the right side mechanically more advantageous and dominant in most individuals.

Question 2

Which phase of the breathing cycle is most associated with spinal extension and posterior rib cage expansion in PRI?

Accepted Answer

Inhalation

Answer

During inhalation the diaphragm descends, the rib cage lifts and expands posteriorly, and the thoracic spine moves into relative extension.

Question 3

A patient is unable to achieve a zone of apposition (ZOA) on the left side. Which compensatory breathing pattern is most likely observed?

Accepted Answer

Dominant left accessory muscle use with elevated left shoulder girdle

Answer

Loss of left ZOA leads to recruitment of accessory muscles on the left (scalenes, upper trapezius) and elevation of the left shoulder girdle as the patient tries to expand the left thorax.

Question 4

The zone of apposition (ZOA) of the diaphragm is best described as the region where the diaphragm:

Accepted Answer

Apposes the inner surface of the lower rib cage

Answer

The ZOA is the cylindrical portion of the diaphragm that lies in direct apposition against the inner aspect of the lower six ribs, allowing it to generate lateral and superior rib expansion with contraction.

Question 5

During a 90-90 hip lift with balloon exercise in PRI, the balloon serves primarily to:

Accepted Answer

Provide resistance that facilitates left ZOA and diaphragm repositioning

Answer

Blowing into the balloon on exhalation creates back-pressure that assists in repositioning the left hemidiaphragm by promoting left ZOA and left thoracic expansion.

(PRC) Postural Restoration Certified Practice Test

(PRC) Postural Restoration Certified Practice Test

PRC Breathing Mechanics & Diaphragm Function 2