PRC Breathing Mechanics & Diaphragm Function 3

Question 1

Which statement best explains why PRI emphasizes exhalation techniques before assessing or correcting postural patterns?

Accepted Answer

Full exhalation repositions the diaphragm inferiorly and restores ZOA, making the patient receptive to repositioning

Answer

Achieving a full exhalation restores the diaphragm to a properly domed position with adequate ZOA, which is a prerequisite for effective postural repositioning in PRI.

Question 2

The right crural attachment of the diaphragm to the lumbar spine primarily influences which lumbar segment most directly?

Accepted Answer

L2-L4

Answer

The right crus of the diaphragm attaches to the anterior bodies of L2-L4 vertebrae, making those segments most directly influenced by diaphragm tension and positioning.

Question 3

A PRI clinician assesses a patient's breathing and notes that the lower ribs flare outward bilaterally during inhalation instead of expanding laterally. This most likely indicates:

Accepted Answer

Loss of ZOA with diaphragm acting as a flat piston rather than a dome

Answer

When the diaphragm loses its ZOA and domed shape it can only pull the ribs outward (bucket-handle flare) rather than lifting them in the optimal lateral and superior direction.

Question 4

In PRI, which muscle pairing is most responsible for creating intra-abdominal pressure that assists diaphragmatic descent during inhalation?

Accepted Answer

Transverse abdominis and pelvic floor

Answer

Co-activation of the transverse abdominis and pelvic floor generates intra-abdominal pressure that resists and modulates diaphragmatic descent, providing the diaphragm a stable base to work against.

Question 5

During normal quiet breathing, what percentage of the total respiratory muscle work is attributed to the diaphragm in healthy adults?

Accepted Answer

About 70-80%

Answer

In healthy adults during quiet breathing, the diaphragm accounts for approximately 70-80% of total ventilatory work, with accessory muscles contributing minimally.

(PRC) Postural Restoration Certified Practice Test

(PRC) Postural Restoration Certified Practice Test

PRC Breathing Mechanics & Diaphragm Function 3