A need for strength makes the bones rigid, but if the skeleton consisted of one solid bone, movement would be impossible! Nature has solved this problem by dividing the skeleton into many bones and creating joints where the bones intersect. Joints come in a variety of designs, each especially built for the limb it serves.
Joints permit bodily movement and are held together by fibers called "ligaments". Joints are "oiled" continuously to prevent friction. Some joints may permit only limited movement, whereas others like the joints in the spine, allow some movement in several directions. Where bones meet, they are lubricated and protected by the synovial fluid. Ageing is accompanied by bone loss and a reduction in the amount and viscosity of synovial fluid. Products that help to improve healthy joints and bones are listed below: |