Interactive Guide to Physical Examination
Thorax & Lungs


Palpation of the chest includes evaluation of thoracic expansion, percussion, and evaluation of diaphragmatic excursion. These techniques may be used to evaluate suspected abnormalities.

Thoracic expansion:

  • Is used to evaluate the symmetry and extent of thoracic movement during inspiration.
  • Is usually symmetrical and is at least 2.5 centimeters between full expiration and full inspiration.
  • Can be symmetrically diminished in ankylosing spondylitis.
  • Can be unilaterally diminished in chronic fibrotic lung disease, extensive lobar pneumonia, large pleural effusions, bronchial obstruction and other disease states.
View video Click on the video icon for further discussion and demonstration of thoracic expansion.


Percussion is the act of tapping on a surface, thereby setting the underlying structures in motion, creating a sound and palpable vibration. Percussion is used to determine whether underlying structures are fluid-filled, gas-filled, or solid. Percussion:

  • Penetrates 5 - 6 centimeters into the chest cavity.
  • May be impeded by a very thick chest wall.
  • Produces a low-pitched, resonant note of high amplitude over normal gas-filled lungs.
  • Produces a dull, short note whenever fluid or solid tissue replaces air filled lung (for example lobar pneumonia or mass) or when there is fluid in the pleural space (for example serous fluid, blood or pus).
  • Produces a hyperresonant note over hyperinflated lungs (e.g. COPD).
  • Produces a tympanitic note over no lung tissue (e.g. pneumothorax).
View video Click on the video icon for a description and demonstration of percussion technique.

Diaphragmatic excursion:

  • Can be evaluated via percussion.
  • Is 4-6 centimeters between full inspiration and full expiration.
  • May be abnormal with hyperinflation, atelectasis, the presence of a pleural effusion, diaphragmatic paralysis, or at times with intra-abdominal pathology.
View video Click on the video icon to view a demonstration of the technique used to assess diaphragmatic excursion.

View interactive module Click on the interactive icon to practice evaluating diaphragmatic excursion.