Lower Limb - Posterior Thigh Muscles (2)

Question 1

What are the hamstrings?

Answer 1

The hamstrings consist of Semitendinosus, Semimembranosus, and Biceps femoris (long head).

Question 2

What is the proximal attachment of all three muscles of the hamstrings?

Answer 2

Ischial tuberosity.

Question 3

Describe the distal attachments of semitendinosus and semimembranosus.

Answer 3

Both attach to the medial surface of upper tibia, as part of the pes anserinus (together with the attachments of sartorius and gracilis). The semimembranosus forms a larger attachment, including a reflected part that is called the oblique popliteal ligament, which goes to the lateral femoral condyle.

Question 4

What is the distal attachment of the biceps femoris?

Answer 4

Fibular head.

Question 5

Describe the innervation to the hamstring muscles.

Answer 5

Tibial division of the sciatic nerve (mostly S1)
Note that the short head of biceps femoris is NOT a hamstring muscle, and it is innervated by the common fibular division of the sciatic nerve.

Question 6

What is the proximal attachment of the short head of biceps femoris?

Answer 6

The inferior third of the linea aspera on the femur.