Hamstring muscles are one of the three posterior thigh muscles in between the hip and the knee. There are three hamstring muscles-
Semitendinosus
Semimembranosus
Biceps femoris
These muscles span the thigh, crossing both the hip and the knee. They originate at just below the buttocks, arising from the ischium. They attached to the tibia and the fibula.
The hamstring muscles flex the knee & extend the hip. The hamstring muscles are not quite active with normal walking or standing.
Hamstring muscle injury is very common in athletics. Most hamstring muscle and tendon damages heal without surgery. The chance of hamstring injury can be overcome with a regular stretching program and exercises.
Hamstring Muscles Attachment
Semitendinosus:
The semitendinosus is a long superficial muscle in the back of the thigh.
Origin: The semitendinosus originates from common tendon with long head of biceps femoris from the superior medial quadrant of the posterior portion of the ischial tuberosity
Insertion: The Superior aspect of the medial portion of the shaft of the tibia.
Action: The semitendinosus extends the thigh and flexes the knee.,and too rotates the tibia medially, particularly when the knee is flexed.
Nerve Supply: Tibial nerve
Semimembranosus:
The semimembranosus is the medial-most of the three hamstring muscles.
Origin: The semimembranosus originates from the superior lateral quadrant of the ischial tuberosity.
Insertion: It inserts into the posterior surface of the medial tibial condyle.
Action: The semimembranosus extends the thigh, flexes the knee, and too rotates the tibia medially, particularly when the knee is flexed.
Nerve Supply: Tibial nerve
Biceps femoris:
The biceps femoris is a muscle of the thigh located to the back of the thigh of the hamstrings muscle group. The biceps femoris has two parts-
Biceps Femoris – Long Head
Origin: The biceps femoris long head originates from common tendon with semitendinosus from the superior medial quadrant of the back portion of the ischial tuberosity of the hip bone.
Insertion: It inserts primarily on the fibular head; further on the lateral collateral ligament and lateral tibial condyle.
Action: The biceps femoris long head flexes the knee, and too rotates the tibia laterally; long head further extends the hip joint.
Nerve Supply: Tibial nerve
Biceps Femoris – Short Head
Origin: The biceps femoris short head originates from the lateral lip of linea aspera, the lateral supracondylar ridge of the femur, and lateral intermuscular septum of thigh
Insertion: It’s inserted primarily on the fibular head; also on the lateral collateral ligament and lateral tibial condyle.
Action: The biceps femoris short head flexes the knee, and too rotates the tibia laterally; long head further extends the hip joint.
Nerve Supply: Common peroneal nerve
Hamstring Muscles Stretching
