| Percussion (medicine) | |
|---|---|
| MeSH | D010474 |
| MedlinePlus | 002281 |
Percussion is a technique ofclinical examination.[1]
Percussion is a method of tapping on a surface to determine the underlying structures, and is used inclinical examinations to assess the condition of thethorax orabdomen. It is one of the four methods of clinical examination, together withinspection,palpation,auscultation, and inquiry. It is done with themiddle finger of one hand tapping on the middle finger of the other hand using a wrist action. The nonstriking finger (known as thepleximeter) is placed firmly on the body over tissue. When percussing boney areas such as theclavicle, the pleximeter can be omitted and the bone is tapped directly such as when percussing an apical cavitary lung lesion typical oftuberculosis.[2]
There are two types of percussion: direct, which uses only one or two fingers; and indirect, which uses only the middle/flexor finger. Broadly classifying, there are four types of percussion sounds: resonant, hyper-resonant, stony dull or dull. A dull sound indicates the presence of a solid mass under the surface. A more resonant sound indicates hollow, air-containing structures. As well as producing different notes which can be heard they also produce different sensations in the pleximeter finger.
Percussion was at first used to distinguish between empty and filledbarrels ofliquor, and Dr.Leopold Auenbrugger is said to be the person who introduced the technique to modern medicine, although this method was used byAvicenna about 1000 years before that for medical practice such as using percussion over the stomach to show how full it is, and to distinguish betweenascites andtympanites.[3]
It is used to diagnosepneumothorax,emphysema and otherdiseases. It can be used to assess the respiratory mobility of the thorax.
It is used to find whether anyorgan is enlarged and similar (assessing for organomegaly). 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.
Based on the auditory and tactile perception, the notes heard can be categorized as:[4]
Percussion may induce pain, this is often also noted as it can indicate underlying pathology.
