The musculoskeletal system is an internal system that functions primarily to protect vital organs while providing motion and overall support for the body. It is made up of bones, muscles, cartilage, ligaments and tendons.
The musculoskeletal system accounts for around 60 percent of human body mass. These groups of interconnected muscles and bones use up a majority of the body's energy as they work toward providing flexibility and movement. Joints exist between separate bones as ligaments to hold those bones together and ensure that they stay in place. Cartilage keeps bones from rubbing directly against one another.
Certain types of arthritis result from a wearing away of the cartilage. A lack of cartilage prevents the joint from operating smoothly.
Muscles keep bones in place, but they also provide movement. Physiologically, muscles move bones by contracting. This contraction is a result of electrical currents sent from the central nervous system into the nerves of muscles. Because muscles are connected to bones by joints, the shortening of the muscle causes movement in the bones to which each muscle is attached.
In general, the skeleton stores calcium and phosphorus, but also contains important components of the blood production system.
The spinal cord is a very important component of the musculoskeletal system. In addition to ensuring that the body maintains an erect posture, the spine also allows the brain to communicate with other areas of the anatomy.