Strain

A strain refers to a tear in a muscle. It is caused by over stretching or over using the muscle.

A muscle is made up of many fibres. When a muscle is "strained", some of these fibres have been torn. A strain can be classified into one of three different categories depending on how many fibres have been torn.

• A first-degree strain means that only a few muscle fibres have been torn. There may be some pain when you try to use the muscle. There will also be pain when you perform a movement that causes the muscle to be stretched.
• A second-degree strain means that half of the muscle fibres that make up the muscle have been torn. There is usually a lot of pain when you try to use the muscle and especially when the muscle is stretched. Because half of the muscle fibres are torn, the muscle is very weak. The pain and weakness caused by a second-degree strain usually makes it very difficult to perform some movements.
• A third degree strain means that the whole muscle has been completely ruptured. Since this muscle can no longer work, a third degree strain causes weakness which leads to a loss of the ability to perform certain movements. For example, if the muscle that is torn usually functioned to straighten your knee, you will not longer be able to straighten your knee. There is pain when the third-degree strain occurs, but if you try to stretch or use the muscle there should be no further pain. As the muscle begins to heal it will act more like a second-degree strain, and therefore pain will be caused with stretching and movement.
  

Other Orthopaedic Conditions
Other Medical Conditions