What are the five types of sounds elicited by percussion, and what does each indicate about the underlying tissue?

Key points

• The five percussion sounds are flatness, dullness, resonance, hyperresonance, and tympany.
• Flatness is an extremely dull sound produced by very dense tissue such as muscle or bone.
• Dullness is a thudlike sound produced by dense tissue such as the liver, spleen, or heart.
• Resonance is a hollow sound produced by air-filled tissue such as normal lungs.
• Hyperresonance is a booming sound not normally produced, but it can be heard over an emphysematous lung.
• Tympany is a musical or drumlike sound produced by an air-filled stomach, and on a continuum flatness is most dense and tympany least dense with the most air.