Musculoskeletal disorders (MSDs) are injuries or pain in the body's joints, ligaments, muscles, nerves, tendons, and structures that support limbs, neck and back. MSDs are degenerative diseases and inflammatory conditions that cause pain and impair normal activities. They can affect many different parts of the body including upper and lower back, neck, shoulders and extremities (arms, legs, feet, and hands). MSDs can arise from a sudden exertion (e.g., lifting a heavy object), or they can arise from making the same motions repeatedly repetitive strain, or from repeated exposure to force, vibration, or awkward posture. Examples of specific MSD disorders are carpal tunnel syndrome, epicondylitis, and tendinitis. Abrasions, contusions, and fractures that occur from sudden physical contact with objects that might occur in an accident are not considered MSDs.