Muscle Strain of the Hamstring Anatomy
To better understand a hamstring strain, it helps to understand the anatomy of the thigh.
The entire leg contains four bones:
The hamstring muscles are a group of three muscles in the back of the thigh:
- Biceps femoris
One end of each muscle attaches to the bottom of the pelvis, and the other end attaches to the end of the femur, at the knee. The hamstring muscles extend the hip (move the hip to the rear) and flex the knee.
The hamstrings are the powerful flexors of the knee joint. They are essential to stabilizing the knee and performing activities such as running.
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