The origin of the word hamstring comes from the old English hamm, meaning thigh. String refers to the characteristic appearance and feel of the tendons just above the back of the knee.
The hamstrings are the tendons that attach the large muscles at the back of the thigh to bone. The hamstring muscles are the large muscles that pull on these tendons. These muscles span the thigh, crossing both the hip and the knee. There are three hamstring muscles (Semitendinosus, Semimembranosus and Biceps Femoris) which are known as the hamstring muscle group. The role of the hamstring muscles is to bend (flex) the knee and to move the thigh backwards at the hip (extend the hip).
Hamstring injuries typically are muscle strain injuries caused by rapid acceleration activities when running or initiating running activity. Hamstring injuries occur when excessive force is placed across the muscles. This typically happens during sudden starts or stops when running, a rapid change of direction with “cutting” or jumping maneuvers, or when the muscle is overstretched by activities such as sprinting, hurdling, kicking, or heavy lifting. Hamstring injuries are common in sports which involves running activity. Injuries to the hamstring group of muscles can range from a minor strain to a major rupture.
Signs and symptoms
When a person injures a hamstring muscle, the symptoms are related to the severity of the injury. Mild hamstring strains often just feel like a pulled or cramping muscle, however, more severe injuries can be painful and symptoms include:
- A sudden, sharp pain at back of the thigh
- A feeling of a “pop” or tearing in the muscle
- Bruising within hours or days after the injury
- Tenderness to touch
- Difficulty in sitting comfortably, lifting the leg when lying down, or straightening the knee
- Difficulty walking, resulting in a limp
- Spasm, tightness, and tenderness.
- With more severe injury, swelling and a black and blue or bruised appearance
- Tears and strains at the middle of the back of the thigh
Risk factors for hamstring injuries include:
- A history of prior hamstring injury
- Muscle imbalances (particularly hamstring weakness)
- Poor flexibility (muscle tightness)
- Inadequate warm-up before activity
- Muscle fatigue
Diagnosis of hamstring injuries starts with a thorough understanding of your health history and the cause of the injury.
Observation: To note any discoloration or bruising
Pain: To identify your current pain level, and the activities that make your pain better or worse
Palpation: To pinpoint the location and size of the tender area through touch, which will help determine the severity of the injury
Range of motion: To compare the motion of your injured leg with your healthy leg
Muscle strength: To determine the strength of the hamstring muscles when bending or straightening your knee and hip
Gait analysis: To note any limping or pain when walking
Typically, hamstring injuries are classified as Grade I – III depending on the severity of the injury.
Grade I: Mild strain with minimal tearing; usually feels like a pulled or cramping muscle
Grade II: Moderate strain with partial tearing; may cause a stinging or burning sensation at the back of the thigh
Grade III: A severe, complete muscle tear; may result in a “lump” on the back of the thigh where the muscle has torn
If a severe injury is suspected, we will recommend an orthopedic physician for medical diagnostic imaging, including x-ray and MRI, to evaluate the extent of the injury. In the event of a fracture of the ischial tuberosity (sit-bone) and/or a complete rupture of the muscle, surgery might be recommended.
Over the years, we at Truecare have come across many sports injuries with hamstring strains being a common condition that we treat. We understand not only the nature of the injury, but also of the lifestyle of the patient; our Physiotherapists are sure to keep your active lifestyle in mind during the course of treatment. We aim to reduce pain and inflammation, improve flexibility and muscle condition, increase the load through the hamstring muscle gradually to a level where the athlete can return to full fitness training.
Hamstring stretching begins with very gentle static stretches initially moving onto more dynamic sports specific stretches as the injury heals. Different stretches will target the muscle in different ways depending on exactly where the muscle tear is. Some hamstring strains are nearer the knee and others may be higher up in the muscle.
Hamstring muscle strengthening is thought of in terms of gradually increasing the load on the muscle. Strengthening exercises should always be done pain free. In the early stages of hamstring rehabilitation basic static exercises are done often using a therapist or partner to provide resistance. These will progress to more sports specific and demanding exercises as the muscle strengthens.
Range of motion
It is common for muscles and joints to become stiff after an injury. As pain decreases, our physical therapist will begin gentle flexibility exercises, such as stretching your hamstring muscles.
Hamstring strengthening will be an essential part of your rehabilitation program. Our physical therapist will compare the strength of the muscle groups in each leg, and prescribe specific exercises to target areas of weakness.
Our physical therapists are trained in hands-on “manual” therapy to move and manipulate muscles and joints to improve motion, flexibility, and strength. These techniques can target areas that are difficult to treat on your own.
As one regains the flexibility and strength in hamstrings, it will be important to teach the body to move so one no longer puts excessive stress on the previously injured area. Our therapist will develop a functional training program specific to the patient’s desired activity.
How can Hamstring injuries be Prevented?
One can decrease the risk of a hamstring injury in the following ways:
- Always warm up before participating in athletic activities.
- Avoid starting a new activity too quickly; gradually increase the frequency and intensity of the activity so that your body may adapt to the new movement patterns.
- Listen to your body after you work out (and stretch, apply ice, rest as needed) prior to engaging in the same routine again.
- Use proper lifting and squatting techniques, particularly when maneuvering heavy objects.