All Muscles Exam 2 - Origin, Insertion, Actions

Rectus Femoris

O: AIIS (Anterior inferior iliac spine)

I: Tibial tuberosity

Actions (2):

Extend the knee

Flex the hip

Vastus Medialis

O: Medial lip of of linea aspera

I: Tibial Tuberosity

Actions (1):

Extend the knee

Vastus Lateralis

O: lateral lip of linea aspera, gluteal tuberosity and greater trochanter

I: Tibial tuberosity

Actions (1):

Extend the knee

Vastus Intermedius

O: Femur

I: Tibial Tuberosity

Actions (1):

Extend the knee

Biceps Femoris

O: Long head: Ischial Tuberosity
Short head: Lateral lip of linea aspera

I: Head of the Fibula

Actions (5):

Flex the knee

Laterally Rotate the flexed knee

Long Head:

Extend the hip

Assist to laterally rotate the hip

Tilt the pelvis posteriorly

Semitendinosus

O: Ischial Tuberosity

I: Tibia at pes anserinus tendon

Actions (5):

Flex the knee

Medially Rotate the flexed knee

Extend the hip

Assist to medially rotate the hip

Tilt the pelvis posteriorly

Semimembranosus

O: Ischial tuberosity
I: Posterior aspect of medial condyle of tibia
ACTIONS (5)
Flex the knee
Medially rotate the flexed knee
Extend the hip
Assist to medially rotate the hip
Tilt the pelvis posteriorly