Percussion is a method used by a doctor to find out about the changes in the thorax or abdomen. It is one of the four methods of clinical examination: inspection, palpation, percussion and auscultation. It is done with the middle finger of right hand tapping on the middle finger of the left hand, which is positioned with the whole palm on the body.

There are four different percussion sounds:

• sonorous
• hypersonorous
• relatively dull sound
• completely dull sound

Percussion of the thorax

It is used to diagnose pneumothorax, emphysema and other diseases. It can be used to access the respiratory mobility of the thorax.

Percussion of the abdomen

It is used to find whether any organ is enlarged and similar. It is based on the principle of setting tissue and spaces in between at vibration. The sound thus generated is used to determine if the tissue is healthy or pathological. The method was initially used to distinguish between empty and filled barrels of liquor.

See also:

• Clinical examination
• Inspection (medicine)
• Palpation
• Auscultation