A strain is an injury of the muscle and/or tendon. Tendons are fibrous cords of tissue that attach muscles to bone. Chronic strains are the result of overuse (prolonged, repetitive movement) of muscles and tendons. Inadequate rest breaks during intensive training precipitates a strain. Acute strains are caused by a direct blow to the body, overstretching, or excessive muscle contraction. In most cases the mechanism of injury resulting in a sprain or a strain may be the same; it’s just a matter of which tissues are damaged in the injury.
A rib sprain is a type of rib injury where one or more ligaments supporting any of the joints between the ribs and spine (vertebrae) or where the ribs attach to the sternum (breastbone) are overstretched or torn. A rib strain is an injury to either the muscles or tendons attaching to the ribs. The muscles that expand the ribcage during breathing are the intercostal muscles, which are located between the ribs.
Overstretching of the ligaments, muscles, or tendons may cause pain, swelling, tenderness, or increased pain with moving or turning your trunk, coughing or breathing deeply. Common causes of rib sprains are falls, car accidents and direct blows to the ribs from contact sports where the affected rib is temporarily displaced at the joint causing stretching or tearing of the ligament, muscle or tendon. Exaggerated or forceful twisting of the body or swinging of the arms can also result in sprains or strains.