The muscles, tendons, ligaments, joints, bones, cartilage, and discs in the spine make up the musculoskeletal system . Some MSDs, such as carpal tunnel syndrome, can affect nerves as well. To understand these injuries, it is necessary to understand the structure and function of various parts of the body. Muscles are tissues made up of very small fibers. Muscles contract and relax to make movement.
Tendons connect muscles to bones.
Tendons are also made up of fibers, but these fibers do not stretch or shrink. The tendons transfer the force from the muscle to move the bone. Some tendons, like those in the wrist and hand, are covered with a sheath that contains a lubricating fluid. These tendons pass back and forth through the sheath as the muscles tighten or relax. Ligaments connect bones to form a joint.