The most dramatic and public hamstring injury occurs when you see an Olympic athlete pull up suddenly in the sprint, grimacing and clutching the back of their thigh. It happens quickly and you can’t run afterwards.

Hamstring Anatomy

The hamstrings are a group of three muscles at the back of the thigh. They are the biceps femoris, semimembranosus and semitendinosus. The biceps femoris is the most often affected.

The hamstrings all start, or originate, on the ischial tuberosity in the buttock, the “seat bones”. They end (insert) around the upper fibula and tibia. The hamstrings cross two joints, the knee and the hip, making their function more complex than one-joint muscles.

Hamstring Injury Anatomy

How Does Hamstring Injury Occur?

The hamstring is most at risk when it is under strain during “eccentric contraction” which means it is both contracting and lengthening at the same time.

The muscle tendons can even be torn off the tuberosity (an avulsion fracture) in cases where the knee is straight and the body bent forward violently and suddenly. This can occur in water skiing.

Most hamstring injuries occur at the junction between the muscle and tendon parts of the whole structure.

Causes of Hamstring Injury

Factors contributing to this injury include poor warm up, lack of flexibility, tiredness and lack of a good strength balance between the knee muscle groups.

If someone has had a hamstring strain before that makes another one more likely. Over-striding, where the athlete tries to speed up by lengthening their stride in running, is known to be a risk.

Hamstring Injury Symptoms

  • Sudden pain and inability to continue the activity, such as when sprinting
  • People may say they heard a pop as the muscle “went”
  • Pain usually occurs early on or late on in the activity
  • Sitting and going up stairs may be painful

Treatment for Hamstring Injury

The severity of a pulled hamstring varies greatly, so treatment is dictated by the degree of the patient’s problems.

Physiotherapy is indicated for the management of hamstring injuries. A physio will treat minor injuries using the PRICE protocol, with rest, ice, compression bandages and elevation to control pain and inflammation. Active range of movement exercises may be suitable after a few days, progressing to isometric exercises with the knee in different positions.

More severe injuries may be splinted with the knee straight and crutches used to take the stress off the hamstrings in walking.

Further treatment progresses through active exercises to resisted exercises, stretching, eccentric strengthening exercises and sport-related training drills. This process is best performed under the supervision of an experienced physiotherapist.

Over the long-term, it is important to maintain flexibility and the ratio of strength between the quadriceps and hamstring muscle groups.

Surgery for Hamstring Injury

Surgery may be needed to clear out large haematomas (bleeds) or to repair the muscle bellies if they have been torn. If the origin of the hamstring has been avulsed (pulled off) then surgery is routinely indicated to reattach it.


  1. Hamstring Injury. NHS Choices.
  2. Brukner P. Hamstring injuries: prevention and treatment – an update. British Journal of Sports Medicine 2014.