Repetitive stress injury refers to a musculoskeletal condition in which repeated stress or strain on a joint causes injury to the tendons, muscles or bursa, a sac of fluid that reduces friction between the tendons and bones. Literally, repetitive stress injury is the wear and tear of these tissues as they work to move the joint. Repetitive stress injury is a general term that encompasses many specific injuries or conditions that result from a person's occupation, hobbies or sports activities.

Some of the specific conditions that are considered repetitive stress injury are carpal tunnel syndrome, arthritis, tendonitis, tennis elbow and trigger finger. These are only a fraction of the hundreds of known conditions that can be described as repetitive stress injury. All of them have basically the same impact on the body, only in different areas.

Regardless of which body part is affected, repetitive stress injury occurs when a particular joint is used constantly to perform the same task. For example, tennis elbow commonly occurs in tennis players because they strain their elbow over and over in swinging the racket. Tennis elbow does not only affect tennis players. Another common victim of tennis elbow is a carpenter who repetitively uses the same joint when wielding a hammer.

Repetitive stress injury is characterized by an extremely painful inflammation of the muscles, tendons and/or bursa around the joint. It is also common for nerves to be pinched due to swelling, causing pain in areas of the body that are not actually injured. For example, a repetitive stress injury in the shoulder area may cause pain in the hand. A person suffering from repetitive stress injury may have difficulty performing the most simple of tasks, like holding a cup of coffee or brushing their hair. Symptoms tend to subside if the affected area is given time to heal.

To relieve pain and soreness, it is usually effective to alternate applying hot and cold packs to the area in 20-minute intervals. Over the counter anti-inflammatory medications are also helpful. Maintaining good posture, relaxation techniques and stretching can significantly reduce the likelihood of developing repetitive stress injury.