How to Treat a Hamstring Pull, Strain, or Tear

Hamstring injuries, such as strains and tears, are common in sports that require either a lot of running or powerful accelerations and decelerations. The hamstrings are comprised of a group of muscles and tendons that extend along the back of the leg from the base of the pelvis to the shinbone. While their primary role is to bend the knee, hamstrings also contribute to the rotation the lower leg.

A hamstring strain refers to an injury in which the muscle or tendon is stretched or torn. Less severe strains are often referred to as a "pulled hamstring." A hamstring tear, also known as a rupture, infers a more serious injury.

Some hamstring injuries are mild and improve with rest and over-the-counter (OTC) pain relievers. Others are more severe and may require surgery and extensive rehabilitation.

An acute hamstring injury will typically cause a sudden, sharp pain in the back of the thigh that can stop you mid-stride. In some cases, you may hear an audible "pop" or feel your leg giving out from under you. A chronic hamstring injury can occur if an untreated tear or strain worsens over time.

After the injury occurs, you will often be unable to extend your knee for more than 30 to 40 degrees without pain. Acute injuries are almost always accompanied by spasm, tightness, and tenderness, either developing immediately or after several hours.

In the case of a rupture, you can often feel or see where an indentation where the tear has occurred. Swelling and severe bruising will typically follow.

Most hamstring injuries are caused when the muscles are overloaded. These include the biceps femoris, semitendinosus, semimembranosus, and knee flexors. Muscle overload occurs when a muscle is either stretched beyond its limits or challenged with a sudden, excessive weight load.

Most strains occur when the hamstring muscles are lengthened and contracted at the same time (known as an eccentric contraction). One such example is sprinting, during which the back leg is straightened while you propel yourself forward on bent toes.

Other injuries occur when the hamstring is overexerted when lifting weight with a sudden thrust of energy. Powerlifting is one such example.

Risk factors include:

• Pushing beyond your current limits
• Improper or no warm-up before exercise
• Tight hip flexors
• Weak gluteus muscles (buttocks)
• Poor flexibility
• Poor muscle strength
• An imbalance between the quadriceps (front of the thigh) and hamstring muscles
• Muscle fatigue during activity
• Differences in leg length

Hamstring injuries can usually be diagnosed by the location and intensity of the pain as well as the restriction of movement. Most tend to occur either at the middle of the back of the thigh or just beneath the gluteus muscle near the point where the tendon connects to the bone.

Most cases do not require imaging tests to confirm the diagnosis. However, severe injuries may need to be assessed with magnetic resonance imaging (MRI), the gold standard for visualizing soft tissue injuries. Alternately, an ultrasound can provide a qualitative assessment of an injury by viewing the muscles and tendons in real time. X-rays, while useful, can sometimes miss smaller tears.

Based on the evaluation, a hamstring injury can be classified as grade I, grade II, or grade III.

Grade I Hamstring Injury

• Muscle stiffness, soreness, and tightness
• Little noticeable swelling
• A normal gait and range of motion, albeit with discomfort
• Ability to flex the knee

Grade II Hamstring Injury

• Muscle pain, sharp twinges, and tightness
• Noticeable swelling or bruising
• An affected gait
• Pain to the touch and when flexing the knee
• A limited range of motion

Grade III Hamstring Injury

• Pain during rest, becoming severe with movement
• Difficulty walking without assistance
• Noticeable swelling and bruising

The treatment of a hamstring injury is based on the severity of the symptoms. All but the most severe can usually be treated non-surgically. Those involving tendon avulsions, in which the tendon has pulled completely away from the bone, require surgery and an extensive rehabilitation program.

Non-Surgical Treatments

Most acute hamstring injuries can be treated at home with the RICE protocol, which involves:

• Rest, often with crutches, to avoid placing any weight on the leg
• Ice, using a cold compress to reduce pain and inflammation
• Compression with a compression bandage to reduce swelling, prevent tissue bleeding, and avoid further expansion of the tear
• Elevation of the leg above the heart to direct blood away from the leg, thereby reducing pain and swelling

More serious injuries may require immobilization with a knee brace to keep your leg in a neutral position. Pain can be treated either with an analgesic such as Tylenol (acetaminophen) or a nonsteroidal anti-inflammatory drug (NSAID) like Advil (ibuprofen) or Aleve (naproxen).

Once the injury is stabilized and the pain and swelling have subsided, physical therapy can be started, using gentle stretching to restore range of motion and strengthening exercises to increase muscle mass and weight-bearing strength.

Surgical Treatment

Avulsions of the hamstring invariably require surgery to reattach the rupture. Avulsions most commonly occur near the pelvis (proximal tendon avulsion), although they can also happen nearer to the shinbone (distal tendon avulsion).

If an acute rupture occurs, the surgeon will usually wait 72 hours to allow the recoiled muscles to "relax." Delaying beyond this point is usually unadvised as the muscle can begin to waste away (atrophy) and develop extensive scarring (fibrosis).

During the tendon avulsion repair, the surgeon will pull the hamstring muscles back into their original position and cut away any scar tissue at the ruptured end. The tendon will then be reattached to the bone with staples and/or stitches. If the muscle itself is ruptured, sutures will be used to reattach the ends without shortening the length too excessively.

After surgery, you would need to use crutches and a brace to keep your leg in a neutral position. Once ample healing has occurred, physical therapy and rehabilitation would begin, lasting anywhere from 3 to 6 months.

Every effort would be made to control pain with regular ice application and OTC pain relievers. If needed, stronger NSAIDs may be prescribed.

Since hamstring injuries typically occur during sports and athletics, routine precautions should be taken in advance of the activities. Among the key prevention tips:

• Always warm up before exercise with eccentric hamstring stretches.
• Approach squats and other exercises that engage the gluteus and hip flexor muscles with caution, starting slowly and gradually increasing in depth.
• Stretch after your workout as well as before. It is important to remember that, with strength training, muscles tend to retract. If stretching is avoided, these muscles can eventually become fixed in this semi-flexed position.
• Add retro-running (running backward) to your workout which helps balance the gluteus and hamstring muscles while strengthening those around the knee.
• To avoid overexertion, follow the 10-percent rule in which you increase the intensity, distance, or duration of your workout by no more than 10 percent week on week.