Muscles of the Posterior Thigh

Question 1

Biceps Femoris:

Long Head

Short Head

Answer 1

origin: ischial tuberosity (LH), linea aspera of femur (SH)
insertion: head of the fibula, lateral aspect
innervation: tibial N. (L4-S3) (LH), common fibular N. (L4-S2) (SH)
action: flexion of knee, extension of the hip (weak), lateral rotation of tibia

Question 2

Semitendinous

Answer 2

origin: ischial tuberosity
insertion: pes anserius, posterior slip
innervation: tibial N. (L4-S3)
action: flexion of knee, extension of hip (weak), medial rotation of tibia

Question 3

Semimembranosus

Answer 3

origin: iscial tuberosity
insertion: medial aspect of the tibial condyle
innervation: tibial N. (L4-S3)
action: flexion of knee, extension of hip (weak), medial rotation of thigh