When you twist an ankle or wrench your back, you probably don't care whether you call it a strain or a sprain, it just hurts. But there is a difference between the two. The distinction isn't a level of severity, as many might suspect. A strain is not a less severe sprain or vice versa. The first difference to note between these two injuries, is their textbook definitions. A strain is an injury to a muscle or tendon, while a sprain is an injury to a ligament. As they are known to affect different types of structures, they are by definition, completely separate ailments. The problem for most, is that they sound so much alike. Structurally and functionally tendons and ligaments perform very different jobs. Both strains and sprains are classified by degrees of severity, ranging from first to third degree. The differences in degrees essentially reflect the degree of overstretching or damaging force applied to the tendon, muscle or ligament. The definitions of each degree are similar in strains and sprains and are described below. First degree: This is a stretching of the tissue (a sprain in ligaments, or strain in tendons) without tearing of the fibers. It is characterized by pain and mild dysfunction of the tissue or body part and minimal to no swelling. Second degree: This is the stretching and partial tearing of fibers. It is characterized by pain, swelling, bruising and moderate to severe dysfunction of the tissue or body part. Third degree: This is the complete tear or rupture of the structure. It is characterized by severe pain, severe bruising and loss of function of the body part. There is a wide variety of severity in both strain and sprains with similarities and differences in both. However, the most important thing to remember is to take care of all injuries appropriately from the onset up until return to your back in the swing of things. First Degree In first degree strains and sprains there is very little actual tissue damage, so detecting whether the injury occurred to a tendon or ligament comes down to whether pain is elicited with the contraction of the muscle or not. Generally, the pain will subside in both first degree sprains and strains in a matter of days. As with any initial injury, ice is the preferred treatment for the first 24-48 hours. Gradual return to activity is usually possible after a few days with complete return usually accomplished in 1-3 weeks, depending on the area of the body injured and the activity performed. Leg strains take a little longer for someone who uses their legs frequently, participating in activities such as biking, walking or running. Shoulder strains tend to take a little longer to heal for swimmers or people who do a significant amount of reaching and lifting of the arms. Second Degree Second degree strains can be quite painful if located in the muscle. Pain can often be felt with mild contractions of the strained muscle and sometimes even at rest. Strains to tendons may not cause as much pain until the area is loaded to a greater level with muscle contractions. Second degree strains in muscles might require attention through massage, physical therapy or other rehabilitation so that scar tissue does not become a problem and inhibit the eventual return of normal function. Second degree strains to tendons may also require treatment to restorefunction and prevent progression into a case of tendinitis. Second degree sprains result in laxity or looseness in the joint the ligament supports. Since there is partial tearing of the ligament in a second degree sprain, the ligament will not be able to resist the same amount of tension it did in its uninjured state. The partial tearing also causes bruising, swelling and pain that are usually best treated with rest, ice and compression followed by gradual resumption of activity. Evaluation by a medical professional might be necessary to determine whether the amount of ligament damage will limit recovery. Second degree sprains will sometimes heal normally without resulting in permanent laxity, which can make further injury more likely. It can take 6-8 weeks for a second degree sprain to fully heal. Third Degree Third degree strains of muscles and tendons are generally a very serious issue and often require surgery. When a muscle or tendon ruptures completely, the two ends typically retract, or pull away from each other, requiring surgery to reattach them. Obviously, after a third degree strain and the resulting surgery, extensive rehabilitation is required. Interestingly, third degree strains often occur with little pain after the initial occurrence. Some even occur with no pain at all, especially in the case of tendon ruptures. In the event of a third degree strain, you should seek medical attention immediately. The longer you wait, the tougher it could be to reattach the ends. Third degree strains can take up to one year to heal and for normal function to return. Third degree sprains vary greatly, often depending on which ligament is involved. While pain, swelling and bruising are usually severe with a complete ligament rupture, some ligaments heal without surgery. If the two ends of the ligament are held in place by the surrounding tissue, scar tissue may develop and provide reattachment. However, if the two ends are not held close (as in the case of the ACL in the knee) surgical reconstruction may be required. Even if a ligament heals, there is no guarantee that it will be as solid as it was originally due to laxity (looseness). Sometimes surgery is required to tighten the ligament. For example, the front ligament of the shoulder may heal but still be too loose to hold the shoulder in the joint. Therefore, a surgery may be required to tighten the ligament so that the shoulder does not dislocate. Third degree sprains should also be evaluated by a medical professional, but it is generally not as crucial or demanding of immediate attention. Source
