Infrasternal Angle (ISA)
Setup
Client supine, hook-lying (knees bent, feet flat). Shirt lifted to expose lower ribcage. Coach stands at the side.
Cueing
Step 1: Palpate the xiphoid process with one hand. Step 2: Trace the inferior costal margin bilaterally with the index fingers to form the V-shape. Step 3: Estimate or measure the angle between the two costal margins. Narrow ISA (<85 deg): expiratory (compressed) pattern -- associated with ZOA loss, diaphragm in poor position. Wide ISA (>95 deg): inspiratory (extended) pattern -- associated with rib flare, poor exhalation. Pressure: light palpation 2/10.
Measurement
Use two rulers or a goniometer placed at the xiphoid, each arm along a costal margin. Record angle. Normal: 85-95 degrees. Narrow (<85) or wide (>95) both significant.
Modality
FAQ
What muscles does Infrasternal Angle (ISA) work?
Infrasternal Angle (ISA) primarily targets the T Spine. It is classified as a professional-level assessment test.
How do you perform Infrasternal Angle (ISA) correctly?
Client supine, hook-lying (knees bent, feet flat). Shirt lifted to expose lower ribcage. Coach stands at the side. Step 1: Palpate the xiphoid process with one hand. Step 2: Trace the inferior costal margin bilaterally with the index fingers to form the V-shape. Step 3: Estimate or measure the angle between the two costal margins. Narrow ISA (<85 deg): expiratory (compressed) pattern -- associated with ZOA loss, diaphragm in poor position. Wide ISA (>95 deg): inspiratory (extended) pattern -- associated with rib flare, poor exhalation. Pressure: light palpation 2/10.
What equipment is needed for Infrasternal Angle (ISA)?
Infrasternal Angle (ISA) requires Assessment Kit. It is categorized as a Pattern Analysis assessment test.
Related Exercises
Anterior Rib Angle (ARA) Assessment
Apical Rib Angle
Lower Chest Expansion
Rib Cage Expansion Asymmetry (Breathing Under Load)
Sidelying Rib Cage Expansion Assessment
Thoracic Extension ROM
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