Hamstring injuries are some of the most common injuries in sports and can be some of the most nagging and difficult to treat. These muscle injuries most often occur in activities and sports that involve sprinting and sudden stops such as track, soccer, and tennis. Also, athletes in sports that involve excessive leg stretching such as martial arts or gymnastics can sustain hamstring injuries.
The hamstring muscles and tendons are those located on the back of the thigh. Beginning at the pelvis, they stretch down the posterior thigh across the hip and knee joint to attach on the upper tibia. The hamstring muscle group is comprised of the semitendinosus, semimembranosus, and biceps femoris. Because of the location and attachment points, they serve to extend the hip and bend the knee.
Initial symptoms usually occur very suddenly during activity. These include pain and inability to continue running and sometimes are accompanied by a snap or pop. Other symptoms, which follow, are swelling, bruising, and weakness.
Muscle overload is the reason hamstring injuries occur. As the muscle or tendon is being rapidly stretched during contraction, the force can cause the tissue to fail and tear. These tears can range from mild to severe and are graded I, II, or III. Grade I strains, often called a pull are mild and heal easily. Grade II injuries are more serious and take longer to heal. Grade III injuries involve a complete tear and may take months to heal. The most severe Grade III injuries involve detachment from the pelvis, often with a small piece of bone, and are referred to as avulsion injuries.
Muscle Tightness - lack of flexibility in the hamstrings is very common but stretching is very helpful in eliminating this factor
Poor Conditioning - lack of physical activity causes generalized weakness leading to a strain during exercise activity
Muscle Fatigue - prolonged activity makes muscles less responsive and more prone to injury
Dehydration - lack of water causes changes in muscle at the cellular level resulting in abnormal contractility and possible injury
Primary treatment is the same as most acute musculoskeletal injuries. Rest and avoidance of aggravating activity is first. Ice is applied initially to reduce pain and swelling. Compression aids in support, decreases pain, and will reduce swelling. Elevation will help as well. Anti-inflammatory medications may also reduce symptoms.
Physical therapy can help recover motion and strength after the initial injury is settled down. It starts with gentle stretching, ice and heat, and then progresses to strengthening and ultimately, sports specific activity.