What is a hamstring tear or strain?A hamstring tear or strain, also called a pulled hamstring, is an injury to one of the back muscles in the back of the thigh. These injuries are common with athletes who participate in sports where they must sprint.
Types of a hamstring tear or strain
- Grade 1 — mild injury that heals within a couple weeks.
- Grade 2 — moderate injury that is typically a partial tear in the muscle; patients are likely to limp when walking and will have occasional twinges of pain during activity.
- Grade 3 — severe injury where the muscle is completely torn or a lump of muscle tissue is torn, and can take months to heal.
Causes of a hamstring tear or strainHamstring tears or strains are typically caused by stretching the soft tissues and muscle beyond their limits. In many cases, the patient will suffer from a hamstring tear or strain when running. Other causes of hamstring tears or strains:
- Limited or lack of warm-up before exercising
- Poor muscle strength or muscle fatigue
- Tight hip flexors or weak glutes
- Differences in leg length
- Poor flexibility
Risk factors for a hamstring tear or strainRisk factors of a hamstring tear or strain are similar to the causes. People who have poor flexibility, poor strength, muscle fatigue and those who do not warm up properly are at greatest risk for developing a hamstring tear or strain. Other risk factors of a hamstring tear or strain include:
- Age — as you get older, you are at higher risk of a pulled hamstring.
- Previous injury — patients with previous hamstring injuries are at higher risk for a future hamstring injury.
- Certain sports — sports that require sprinting or sudden change in direction put patients at a higher risk for suffering a hamstring tear or strain.
Symptoms of a hamstring tear or strainThe immediate symptom of a hamstring tear or strain is a sudden, sharp pain in the back of the upper leg. The pain may be so severe it stops you from continuing your activity.
Symptoms depend on the grade of the tear:
- Grade 1 — tightness in the muscle while stretching, inability to fully move your leg from bending to straightened, and inability to bear weight on the leg affected.
- Grade 2 — reduced muscular strength, limping when walking, and pain when bending the knee.
- Grade 3 — a severe, sudden, sharp pain in the back of the thigh, inability to extend the knee more than 30 to 40 degrees, inability to walk without pain, and severe bruising around the impacted area.
Diagnosis of a hamstring tear or strainA hamstring injury is diagnosed in a visit with your primary care or orthopedic provider. The doctor will take a full medical history and physical exam.
During the physical exam, the doctor will evaluate the swelling, tenderness and range of motion in the leg. In moderate tears or strains, the physician may be able to feel a divot in the muscle.
Your provider may also order diagnostic testing, like an MRI or x-ray, if he or she thinks you have sustained other, more serious injuries that need a different treatment regimen.
Treatments for a hamstring tear or strainMild to moderate strains can often be treated at home with rest, ice, compression and elevation in combination with anti-inflammatory medications. Crutches also may be recommended to help the patient get around.
- Braces — braces can help keep the area stable during the recovery process.
- Physical therapy and rehabilitation — although most hamstring tears will heal on their own, they need special exercises and therapy to return to full function.
- Platelet rich plasma (PRP) injection — a PRP injection can help expedite the healing process by injecting growth factor platelets from the patient’s own blood back into the injured area.
Recovery from a hamstring tear or strainThe first phase of recovery is working to decrease the inflammation in the pulled muscle. The second phase of recovery works to build the normal supply of blood to the affected area. The final stage in the recovery process from a hamstring tear or strain works to repair the muscle that will allow the person to resume day-to-day activities.
Mild to moderate (grade 1 or 2) tears or strains can heal within three to eight weeks with diligent home therapy. For a grade 3 hamstring tear or strain, recovery may be as long as three months.
Returning to sports before the injury is fully healed can cause more severe injuries.