Bone is a living structure made up of calcium (hydroxyapatite) and proteins. Bones give the shape and structure to the body and protects other organs. Bones do have blood supply and keep remodelling themselves constantly. Bones are one of the few structures which have got the potential to self heal in the appropriate condition.
Cartilage is the smooth lining of the joint. It is present in most joints. It prevents the sharp edges of the bone from rubbing against each other. Cartilage does not have blood supply and hence is poor at self healing.
Joint is the place where 2 bones meet. Joints are designed to allow movement in certain directions. Joints naturally like movement and keeping them still for long leads to stiffness.
Ligaments are the rubbery ropes holding the two bones together at the joint. The ligaments allow movement in a certain direction and become stiff in the opposite direction. Ligaments outside the joint have potential to self heal to an extent, but not the ligaments in the middle of the joints.
Muscle is a sofisticated structure which contracts and stretches to help place a particular joint in a particular position. Muscles have good blood supply and have a good potential to self heal. Muscles naturally like to move and stretch. Keeping them still in a certain position for long periods makes them become stiff and also become weak (atrophy).
Nerves are cord like structures which pass all the way fron brain to spinal cord to the tips of our hands and feet. They are the wires which carry the signals for our muscles to move. They also carry the signal back to the brain regarding the position and condition of our joints and other structures.
Tendon is the tail part of the muscle which connects it to the bone. Tendon is a rubbery stiff structure which has got very minimal stretching capacity. The structure and components of the tendon and ligament are similar in many regards.
Blood vessels are of two types, namely the arteries and veins. The arteries carry blood from the heart to the hands and feet. Veins bring the blood back from the extremities to the heart. If arteries are not functioning well, one may experience pain on walking or worse death (necrosis) of the toes and further structures upwards. If veins are not functioning well, then one would experience swelling and ache in the legs or arms.