What are the parts of the musculoskeletal system?
The musculoskeletal system works to help you stand, sit, walk, run and move. Adult bodies have 206 bones and more than 600 muscles, connected by ligaments, tendons and soft tissues.
The parts of the musculoskeletal system are:
Bones: Bones of all shapes and sizes support the body, protect organs and tissues, store calcium and fat and produce blood cells. A bone’s hard outside shell surrounds a spongy center. Bones provide structure and form for your body. They work with muscles, tendons, ligaments and other connective tissues to help you move.
Cartilage: A type of connective tissue, cartilage cushions bones inside the joints, along the spine and in the ribcage. Firm, rubbery cartilage protects bones from rubbing against each other. You also have cartilage in your nose, ears, pelvis and lungs.
Joints: Bones come together to form joints. Some joints have a large range of motion, such as the ball-and-socket shoulder joint. Other joints, like the knee, allow bones to move back and forth but not rotate.
Muscles: Each muscle is made of thousands of stretchy fibers. Your muscles allow you to move, sit upright and stay still. Some muscles help you run, dance and lift. You use others to write your name, fasten a button, talk and swallow.
Ligaments: Made of tough collagen fibers, ligaments connect bones and help stabilize joints.
Tendons: Tendons connect muscles to bones. Made of fibrous tissue and collagen, tendons are tough but not very stretchy.
What conditions and disorders affect the musculoskeletal system?
Hundreds of conditions can cause problems with the musculoskeletal system. They can affect the way you move, speak and interact with the world. Some of the most common causes of musculoskeletal pain and movement problems are:
Aging: During the natural aging process, bones lose their density. Less-dense bones can lead to osteoporosis and bone fractures (broken bones). As you age, muscles lose their mass and cartilage begins to wear away, leading to pain, stiffness and decreased range of motion. After an injury, you may not heal as quickly as you did when you were younger.
Arthritis: Pain, inflammation and joint stiffness result from arthritis. Older people are more likely to get osteoarthritis as cartilage inside joints breaks down, but the condition can affect people of all ages. Other types of arthritis also cause joint pain and inflammation, including rheumatoid arthritis, ankylosing spondylitis and gout.
Back problems: Back pain and muscle spasms can result from muscle strains or injuries like a herniated disk. Some conditions, including spinal stenosis and scoliosis, cause structural problems in the back, leading to pain and limited mobility.
Cancer: Several types of cancer affect the musculoskeletal system, including bone cancer. Tumors that grow in connective tissue (sarcomas) can cause pain and problems with movement.
Congenital abnormalities: Also known as birth defects, congenital abnormalities can affect the body’s appearance, structure and function. Clubfoot is one of the most common musculoskeletal problems babies are born with. It causes stiffness and reduced range of motion.
Disease: A wide range of diseases affect how bones, muscles and connective tissues work. Some, such as osteonecrosis, cause bones to deteriorate and die. Other disorders, such as fibrous dysplasia and brittle bone disease (osteogenesis imperfecta), cause bones to fracture easily. Conditions that affect the skeletal muscles (myopathies) include more than 30 types of muscular dystrophy.
Injuries: Hundreds of injuries can affect bones, cartilage, muscles and connective tissues. Injuries can result from overuse, such as carpal tunnel syndrome, bursitis and tendinitis. Sprains, muscle tears, broken bones and injuries to tendons, ligaments and other soft tissues can result from accidents and trauma.
