<Tr> <Th> FMA </Th> <Td> 9692 </Td> </Tr> <Tr> <Td_colspan="2"> Anatomical terminology (edit on Wikidata) </Td> </Tr> <P> A bursa (plural bursae or bursas) is a small fluid - filled sac lined by synovial membrane with an inner capillary layer of viscous synovial fluid (similar in consistency to that of a raw egg white). It provides a cushion between bones and tendons and / or muscles around a joint . This helps to reduce friction between the bones and allows free movement . Bursae are found around most major joints of the body . </P> <P> There are four types of bursa: adventitious, subcutaneous, synovial, and sub-muscular . Among these, only adventitious is non-native . When any surface of the body is subjected to repeated stress, an adventitious bursa develops under it . Examples are Students' elbow and bunion . </P>

The function of a bursa is to reduce friction