Synovial joints are joints with bone ends that are enclosed in a capsule containing synovial fluid, according to the TRB Chemedica. The ends of the bones are composed of a smooth layer of a tough, rubbery substance called cartilage. Strong, fibrous tissue makes up the capsule, which is lined with a membrane known as the synovial membrane.Continue Reading
The BBC explains that all synovial joints consist of synovial fluid, a synovial memrane, cartilage, a tendon and a ligament. Cartilage serves as a shock absorber and reduces friction. Synovial fluid lubricates joints, while synovial membrane produces synovial fluid. Tendons join muscle-to-bone, enabling movements, whereas ligaments join bone-to-bone movements and stabilize the joint. Limbs use joint actions to move in various directions.
There are six ways that synovial joints move, says Dawn A. Tamarkin of the Springfield Technical Community College. Ball-and-socket joints allow for freedom of rotation and back-and-forth movement in all planes. Condyloid joints let bones move in different directions, although the bones cannot rotate. Plane joints provide plenty of flexibility in movement direction, but they have a limited distance in movement. Hinge joints enable easier movement in one plane, without twisting or sliding side-to-side movements. Pivot joints allow bones to spin around on other bones, and saddle joints enable movement between bones with concavities and convexities.Learn more about Bones