An injury to the hamstring muscle is a painful problem, frequent among athletes, especially those who sprint, or run and stop suddenly. The hamstring is not a single muscle, but three muscles located at the back of the thigh. A hamstring injury may involve a strain, which is a stretching or partial tearing of the muscle, or an avulsion injury, which is a complete tear of the muscle, pulling it away from the bone. Because hamstring injuries are usually the result of one of the muscles being stretched beyond capacity, such injuries are commonly referred to as "pulled hamstrings."
Risk Factors for a Hamstring Injury
While a hamstring injury can happen to anyone, individuals are at greater risk of suffering such an injury if they:
- Participate in running, soccer, tennis, football, basketball or dance
- Have had a previous hamstring injury
- Are not flexible or have not stretched prior to exercise
- Have a muscle imbalance between the quadriceps and hamstrings
- Are adolescents in the midst of a growth spurt
Symptoms of a Hamstring Injury
Patients with a hamstring injury may experience any of all of the following symptoms, depending on the severity of the tear:
- Sudden pain during exercise
- Snapping or popping sensation
- Pain in back of thigh or lower buttock
- Tenderness and bruising at the site
- Weakness in the hip or knee
- Tingling sensation at the back of the thigh
Since the hamstring muscles make it possible to extend the leg straight behind the body and to bend the knee, pain during these movements may be a sign of a hamstring injury.
Diagnosis of a Hamstring Injury
To determine whether the hamstring has been injured and to what extent, the doctor will take a medical history and perform a physical examination of the area. With the patient lying face down, the doctor will look for any sign of tenderness, bruising or muscle spasm on the back of the thigh and will move the leg into different positions to try to pinpoint the region of the damage. If the patient has difficulty putting weight on the affected limb, further diagnostic testing will likely be required, first X-rays to rule out any possible fracture, and then an MRI scan or ultrasound to view the hamstring tear itself.
Hamstring Injury Treatment
Treatment for a hamstring injury depends on the severity of the damage, but many cases will heal with minimal care. Patients can relieve symptoms and facilitate the healing process through home remedies such as resting, applying ice and taking anti-inflammatory medications to diminish pain and swelling. Physical therapy is also typically very beneficial, as it works to gently stretch and strengthen the hamstring muscle. As the symptoms improve, gradually increasing exercise may prevent a recurrence of the injury. Generally, most patients can resume normal activities and sports participation in 4 to 6 weeks when the symptoms are gone.
If these conservative measures are not effective for a partial tear, an injection of either corticosteroids or platelet rich plasma may be recommended. These treatments can provide significant relief from pain and assist in the healing of damaged tissue. Severe hamstring injuries may require surgery to repair the torn muscle, especially in athletic patients, who may otherwise experience weakened muscles or other limitations in their ability to fully engage in the sports of their choice.