Muscles of Posterior Thigh: Extensors of Hip and Flexors of the Knee

What is the proximal attachment of the semitendinosus m.?

Ischial tuberosity

What is the distal attachment of the semintendinosus m.?

Proximal part of medial surface of tibia (as part of pes anserinus)

What is the innervation of the semitendinosus m.?

Tibial Division of Sciatic Nerve (L5, S1, S2)

What is the action of the semitendinosus m.?

Extends hip joint; flexes knee joint and medially rotates it when flexed; when hip and knee joints are flexed, these muscles can extend trunk at hip joint

What is the proximal attachment of the semimembranosus m.?

Ischial tuberosity

What is the distal attachment of the semimembranosus m.?

Posterior part of medial condyle of the tibia; reflected attachment forms the oblique popliteal ligament (to lateral femoral condyle)

What is the innervation of the semimembranosus m.?

Tibial Division of Sciatic Nerve (L5, S1, S2)

What is the action of the semimembranosus m.?

Extends hip joint; flexes knee joint and when flexed medially rotates it; when hip and knee joints are flexed, these muscles can extend trunk at hip joint

What is the proximal attachment of the biceps femoris m.?

Long Head: ischial tuberosity

Short Head: linea aspera and lateral supracondylar line of femur

What is the distal attachment of the biceps femoris m.?

Lateral side of head of fibula; tendon is split at this site by fibular collateral ligament of the knee

What is the innervation of the biceps femoris m.?

Long Head: Tibial Division of Sciatic Nerve (L5, S1, S2)

Short Head: Common Fibular Division of Sciatic Nerve (L5, S1, S2)

What is the action of the biceps femoris m.?

Flexes knee joint and laterally rotates it when flexed; long head extends hip joint