Synovial Joints Diarthroses

The third group of joints are the diarthroses (die-ar-THROW-seez) or synovial (sin-OH-vee-al) joints. The word, diarthrosis (die-ar-THROW-sis), means a ''double'' (di-) ''joint'' (arthr) ''condition'' (-osis). You probably know of certain people who are said to be ''double-jointed.'' Such people have an unusually high degree of mobility of the interphalangeal (in-ter-fah-lan-JEEL) joints located ''between'' (inter-) their ''finger or toe bones'' (phalanges). Therefore, the diarthroses are the freely movable joints, with bones so movable that many do seem to be double-jointed!

''What about the synovial name?'' you ask. Synovial ''pertains to'' (-al) ''eggs'' (ovi) whose whites have been poured ''together'' (syn-). This creative thinking reflects the gross appearance of the actual synovial fluid found within the joint cavity. Secreted by a synovial membrane lining the joint cavity, the synovial fluid is clear, thick, and slimy. Thus, it closely resembles the raw whites of many eggs that have been poured into a frying pan together! The slippery and slimy nature of synovial fluid enables it to significantly reduce bone friction and wear while the body carries out most of its major movements.

0 0

Post a comment