Hamstring Strain (Pulled Hamstring)

CONDITION

The hamstrings are a group of three large, powerful muscles at the back of your thigh that enable you to bend your knee. They attach your sitting bones (the back underside of your pelvis), to your thigh bone (femur) and to the bones that make up your knee (tibia and fibula). Each hamstring muscle is attached to bone by a thick, strong band of tissue called a tendon. A hamstring strain, also known as a pulled hamstring, happens when any of the hamstring muscles or tendons on the back of your thigh stretches and tears (Figure 1).

  • Hamstring strains are the most common muscle injury to the thigh.
  • Hamstrings can be torn within muscle, where muscle joins with tendon, within tendon or where tendon attaches to bone.
  • Tears most often affect a hamstring in the mid-thigh, followed by an upper hamstring in the lower buttock, then a lower hamstring just above or at the knee.
  • Most hamstring strains will get better over time with rest. Rarely, completely or significantly torn hamstrings will require surgery.
  • Strains occur at any age but are more common in adults, especially in those over age 40.
Figure 1.

CAUSES

  • Hamstrings are torn during forceful muscle contractions, especially in sports with a lot of running, jumping and kicking. Sprinters, hurdlers and high-jumpers are especially at risk.
  • Hamstrings can be torn with overstretching when the body bends forward quickly at the waist over a straight leg. This may occur during activities such as water skiing, dancing, ice skating and, sometimes, weightlifting.
  • Risk factors for hamstring injury include:
    • inflexible hamstrings
    • weak hamstrings
    • strength imbalance between the hamstrings and the quadriceps, the muscle on the front of the thigh
    • muscle fatigue
    • inadequate warm-up before sports
    • previous hamstring strain or injury
    • smoking.

SYMPTOMS AND SIGNS

  • You will notice pain that starts right away with the injury. Pain is often burning, “hot,” sharp and/or stabbing.
  • You sometimes hear a pop or feel a snap when you tear through your hamstring muscles and tendons.
  • You will feel pain where you tore your hamstring in you lower buttock, upper thigh, mid-thigh or above or over the back or sides of your knee.
  • You may notice aching, throbbing and/or muscle spasm hours to days after the injury.
  • You may notice sudden leg weakness where you tore your hamstring and you will have difficulty running and bending forward at the waist.
  • You will have pain and, sometimes, a depression where the muscle is torn when you reach around and press over the injured area.
  • You may notice bruising in the area of your hamstring strain. Bruising can spread over the entire back of your thigh and lower leg because bleeding causes bruising and gravity makes blood from the injury move toward the foot.
  • Sometimes, there will be a painful lump or swollen area over the back of your thigh. This can be either muscle that has pulled back from a torn tendon or a large collection of blood from a tear.
  • You will have pain over your injury with any attempt to stretch your injured hamstring.

WHEN TO CALL YOUR DOCTOR

Call your doctor right away (day or night) if:

  • You have severe pain and weakness over the back of your thigh that occurs after an injury.
  • You have so much pain that you can’t walk without crutches.
  • You notice a large lump or swelling over the back of your thigh after an injury.
  • You have numbness, tingling or loss of sensation in any part of your thigh, lower leg or foot and toes after an injury.
  • You have moderate to severe pain when you sit over the bones in your lower buttock where your hamstrings attach.
  • You felt or heard a pop just above or around the back or sides of your knee, and have pain and weakness of your thigh and knee.

Call your doctor during regular office hours if any of the following symptoms continue beyond a week or two of trying the self-care measures suggested below:

  • You have mild to moderate pain, weakness, swelling and/or bruising over the back of your thigh after an injury.
  • You have mild pain near your lower buttocks over your sitting bones.
  • You are having difficulty doing normal daily activities or going up stairs.
  • Your injury seems to be getting worse in any way

SELF-CARE AT HOME

For severe injuries that require you to call your doctor right away:

  • Use crutches to take the weight off your injured leg.
  • Wrap your thigh snugly with a large elastic wrap until you see your doctor.
  • Use ice packs or cold packs over the injured hamstring. Put the ice pack or cold pack over the elastic wrap and hold it in place with plastic wrap.
  • You may take acetaminophen (Tylenol®) for discomfort. (See the label for dosing and risks.) Until you talk to your doctor, however, avoid anti-inflammatory medications such as ibuprofen (Advil®, Motrin®) because they may slightly increase the risk of bleeding into your muscle after a strain.

For injuries that do not require immediate medical attention (see above):

  • Rest from all activities that cause symptoms until all of your symptoms go away.
  • Avoid running, jumping and kicking until your symptoms have gone away. Be careful when bending over forward at the waist until your symptoms have gone away.
  • Wrap your thigh snugly with a large elastic wrap and wear it as much as you can for the first 24 to 36 hours to minimize swelling and bruising.
  • For the first few days after injury, elevate your injured leg on a couch or chair as often possible and for as long as you can.
  • Place an ice pack or cold pack over the back of your thigh over the injury for 20 minutes at a time.
    • To minimize pain, swelling and bruising, use the cold pack or ice pack every hour or two for the first 24 to 36 hours.
    • After the first day or two, use cold packs three to six times daily or more often if your symptoms demand it.
    • If you are not using an elastic wrap directly over your skin, place a thin washcloth between the cold pack and your skin to minimize the risk of frostbite. You can hold the cold pack in place with an elastic wrap.
    • If you are busy, you may choose to ice during meals so as to save time and avoid interrupting other activities.
  • You may take ibuprofen (Advil®, Motrin®) or naproxen (Aleve®) for swelling and pain. (See labels for dose and risks.)
  • Once your soreness starts to get better after the first few days following injury, you may start gentle stretching and strengthening exercises. Avoid aggressive stretching that causes pain because it can cause further injury to your hamstrings.
  • Stretch your hamstrings gently two to three times once daily. Avoid bouncing during stretching and hold stretches for 20 seconds (Figure 2).
    • Lie on your back on the floor and bring your injured knee as close to your chest as you can. Then gently straighten your knee by tightening your front thigh muscles or pulling your foot toward your head with a towel or a piece of rope until you feel a stretch over your injured hamstring.
  • Figure 2.
  • At first, strengthen your hamstrings by simply contracting them when you are not moving your leg.
    • This is best done by sitting in a chair and pushing your foot downward into the floor using your hamstrings (Figure 3).
    • To begin with, push gently for five to 10 seconds at a time and repeat five to 10 times. As your symptoms improve and your hamstring gets stronger, you may start to push harder and hold up to 30 to 45 seconds.
  • Figure 3.
  • When the above strengthening exercise gets easy and your hamstring starts to feel better, you can do a slightly more difficult strengthening exercise:
    • Sit in an office chair with wheels or rollers. Extend your injured leg straight out in front of the chair, heel on the floor. Then, gently pull the chair toward your heel until your knee is bent to about 90 degrees (Figure 4).
    • Repeat until you have pulled yourself across an average-size room 10 to 20 times. Do this exercise twice daily.
    • Wear shoes that grip the floor well so that your foot does not slip or slide.
  • Figure 4.
  • In a few weeks, when your hamstring is almost better, you may use a partner to do more difficult hamstring strengthening exercises (Figure 5).
    • Kneel and place a foam pad or couch cushion under your knees. Have your partner hold the backs of your ankles down into the floor. Keeping your back straight, slowly lower yourself forward toward the floor.
    • When you get to the floor, do a quick push up and “snap” smoothly back to a kneeling position, using only your hamstrings to help you up.
    • At first, do this five to 10 times. Do two to three sets daily.
  • Figure 5.
  • After a few weeks and after completing the above strengthening exercises, you may attempt functional drills to see if you are ready to start sports or regular exercise again. You may progress through a series of drills by completing each one pain-free. If you get symptoms when you do a drill, stop and try it again in a day or two.
    • Jog a straight 50-yard line at about 50-percent intensity.
    • Run a straight 50-yard line at 75-percent, then 100-percent intensity.
    • Using the same intensity progressions, run a straight line and progress through 45-degree cuts and then 90-degree cuts to the right and to the left.
    • Then, run a large or “loose” figure-of-eight path. Gradually make it smaller or “tighter” and faster with repeat attempts.

When you can do all of these drills pain-free, you can try sports-specific activity. When you return to specific sports or exercise activity, at first try sports-specific drills or exercise at only 50-percent intensity and in a non-competitive setting. Progress in intensity and sports participation only if you can do so without pain.

  • When you return to activity, you may want to use a neoprene, cloth, or elastic thigh wrap to help minimize symptoms (Figure 6). You can buy sleeves at sporting goods stores or online.
  • Never return to activity until you trust your leg, it has normal strength and flexibility, and you can participate in sports or activities pain-free.

PREVENTION

Maintain adequate hamstring flexibility, properly warm-up before sports, keep your hamstrings strong, and use proper sports and running form.

FOR MORE INFORMATION

REFERENCES

Last reviewed: November 2009

Last revised: November 2009