What are the five percussion sounds and what does each indicate?

The five percussion sounds are flatness, dullness, resonance, hyperresonance, and tympany. Flatness, an extremely dull sound, indicates very dense tissue such as muscle or bone. Dullness, a thudlike sound, indicates dense tissue such as the liver, spleen, or heart. Resonance, a hollow sound, indicates air-filled lungs, while hyperresonance, a booming sound heard in emphysematous lungs, is not produced in the normal body. Tympany, a musical or drumlike sound, indicates an air-filled stomach.

Percussion elicits five types of sound that help determine whether underlying tissue is fluid filled, air filled, or solid. Flatness is soft, high-pitched, and extremely dull, and it is produced by very dense tissue such as muscle or bone. Dullness is medium in intensity and pitch with a thudlike quality, produced by dense organs such as the liver, spleen, or heart. Resonance is loud, low-pitched, and hollow, and it is the normal sound heard over air-filled lungs. Hyperresonance is very loud, very low-pitched, and booming; it is not produced in the normal body and can be heard over an emphysematous lung. Tympany is loud and high-pitched with a musical or drumlike quality, produced by an air-filled stomach. Along a continuum, flatness corresponds to the most dense tissue with the least air, while tympany corresponds to the least dense tissue with the greatest amount of air.