What are the three hamstring muscles? it is Biceps femoris, Semitendinosus, Semimembranosus.
Where is the hamstring muscle located? Right Behind your Thighs, The hamstrings are a group of four muscles located in the back of the thigh. They run from the pelvis down to the knee and help bend the knee and extend the hip. The hamstrings are quite susceptible to injury.
Biceps femoris
The biceps femoris is the muscle of the back thigh. it names says itself that it has two-part( Biceps- two head). the long and short heads. Sometimes short head may be absent. The muscle's Blood supply is derived from the anastomoses of several arteries, the perforating branches of the profunda femoris artery, the inferior gluteal artery, and the popliteal artery.
Biceps femoris ORIGIN:
Biceps femoris Has two heads as it originates from two separate origins.
the long head originates from the ischial tuberosity.
the short head originates from linea aspera & distal femur.
Biceps femoris INSERTION:
it is inserted by common tendon into the head of a fibula & lateral condyle of the tibia.
Biceps femoris ACTION:
Biceps femoris is responsible for the extension of thigh & flexes the knee.
it also laterally rotates leg when the knee is flexed.
Biceps femoris NERVE SUPPLY:
Biceps femoris is innervated by the Sciatic nerve.
Semitendinosus
The semitendinosus is a long superficial muscle in the back of the thigh. It is so named because it has a very long tendon of insertion.
Semitendinosus ORIGIN:
Semitendinosus originates from iscial tuberosity.
Semitendinosus INSERTION:
Semitendinosus inserted at the medial aspect of the upper tibial shaft.
Semitendinosus ACTION:
extends thigh & flexes the knee.
medially rotates leg with semimembranosus.
Semitendinosus NERVE SUPPLY:
Semitendinosus innervated by the Sciatic nerve.
Semimembranosus
The semimembranosus is the most medial of the Four hamstring muscles. it is very flat tendon-like muscles, as it named membranosus.
Semimembranosus ORIGIN:
the ischial tuberosity is the origin of Semimembranosus.
Semimembranosus INSERTION:
it is inserted at the medial condyle of the tibia.
Semimembranosus ACTION:
it extends thigh & flexes the knee and medially rotates the leg.
Semimembranosus NERVE SUPPLY:
Semimembranosus supplied by the Sciatic nerve.
