Hamstring Strains

The hamstring muscle group is located on the back of the thigh, running from the ischial tuberosity (the “butt bone”) to either side of the front of the tibia (shin bone), just below the knee joint. There are three muscles that make up the hamstrings muscle group (on each side) – the biceps femoris, semitendinosis, and semimembranosis. For the purposes of this article, “hamstrings” indicates all three of these muscles collectively. The hamstrings are 2-joint muscles, crossing and affecting movement at both the hip and knee joints.

Primary functions of the hamstrings are to:

• flex the knee (bend the knee by bringing the heel up toward the butt)
• extend the hip (bringing your leg backwards)
• control lowering the trunk when bending forward
• decelerate leg swing during walking and running

Hamstring strains are among the most common injuries (of any kind) to the thigh. They can occur during quick, forceful muscle contractions or during passive, often sudden, stretches of the muscle that go beyond the muscle’s normal flexibility. When musculotendinous units are stretched (either actively or passively) beyond their limits – especially if this stretching happens very rapidly – the weakest spot in the muscle-tendon complex will breakdown. Sudden changes of direction, slipping but trying to prevent a fall (using your leg and core muscles to “catch” yourself instead of face-planting), and accidental sudden over-stretching are among the most common causes of hamstring strains. Other factors that can predispose a hamstring to be strained include muscle fatigue, poor mechanics and posture, a difference in leg lengths, tight hamstrings, or a muscular imbalance.

Signs and Symptoms

• Pain, increased with using the hamstring
• Tenderness over a specific spot of the hamstring
• Feeling something tear or pop at the time of the injury
• Feeling a sudden rush of warmth in the middle of the back of the leg at the time of the injury
• Weakness with using the hamstring
• Pain when placing the hamstring in a stretch
• Reduced flexibility in the hamstring
• Severe hamstring strains will have a palpable defect or divot in the muscle, over the site of the injury
• Bruising is possible

At-Home Treatment

• Initial rest – Depending on severity of the injury, this can either be absolute rest or relative rest (avoiding activities that use the hamstring). This time period also includes resting from stretching your hamstring and adductors (the muscles on the inside of your thigh) for at least 2-3 days to avoid furthering the strain during the initial healing phase.
• Ice on a stretch – Icing the muscle while it is “on a stretch” is different from actually stretching the muscle. Icing on a stretch simply means to ice the muscle when it is at its maximum comfortable resting length. For the hamstring, this most often means sitting with your back supported and upright and your legs straight out in front of you. If the muscle is iced in a shortened position, the muscle will effectively “shrink” to that size temporarily, making it feel stiff and painful when you try to return it to its normal length and/or use it (like to walk).
• Over-the-counter pain medicine – Always be sure to follow the label’s instructions.

Transition into:

• Heat before activity
• Gentle stretching – The purpose of this stretching is not to increase your overall flexibility in the long-term; it is designed to relieve pain and help you feel less “tight”. This means that you may not “go as far” when you’re stretching during this period of healing, but that’s ok!
• Restricted activity (with really good warm-up) – Avoid the types of activities that can lead to hamstring strains. In this stage of treatment, you must perform all activities under control and within your hamstring’s normal range of flexibility.

Proper and complete rehabilitation is necessary following a hamstring strain because the fibrous scar tissue that results from a strain actually puts the muscle at an elevated risk of suffering a strain at the same site in the future. Additionally, incomplete recovery from a hamstring strain (or premature return to full activity) can lead to a cycle of constant re-injury within the musculotendinous unit that can be difficult to break.

When to Seek Help

Go see a doctor if you have:

• shooting pain down the center line of the back of your thigh (this can indicate sciatic nerve involvement instead of hamstring pain)
• pain throughout your leg that persists for more than a day (rather than being confined to one specific area)
• numbness or tingling (that isn’t caused by your leg falling asleep)
• pain that travels into your lower leg/foot or up into your back