Gross Anatomy I Unit III - Muscles of the posterior hip and posterior thigh

What are the posterior hip (gluteal) muscles?

1. Tensor Fascia Lata

2. Gluteus Maximus

3. Gluteus Medius

4. Gluteus Minimus

5. Piriformis

6. Superior Gemellus

7. Obturator Internus

8. Inferior Gemellus

9. Obturator Externus

10. Quadratus Femoris

What is the origin of the tensor fascia lata?

Crest/Ilium

What is the insertion of the tensor fascia lata?

Iliotibial tract

What actions does the tensor fascia lata carry out?

1. Flexes femur

2. Abducts femur

3. Medially rotates femur

4. Helps stabilize the knee

What is the nerve supply of the tensor fascia lata?

Superior gluteal nerve

What are the origins of the gluteus maximus?

1. Posterior gluteal line/ilium

2. Sacrum

3. Coccyx

4. Posterior ligaments of SI joint

What are the insertions of the gluteus maximus?

1. Gluteal tuberosity/femur

2. Iliotibial tract

What actions does the gluteus maximus carry out?

1. Extends the femur

2. Laterally rotates the femur

3. Stabilizes knee

4. Helps stabilize the pelvic bone

What is the nerve supply of the gluteus maximus?

Inferior gluteal nerve

What is the origin of the gluteus medius?

External surface of the ilium between the posterior and anterior gluteal lines

What is the insertion of the gluteus medius?

Greater trochanter/femur

What actions does the gluteus medius carry out?

1. Abducts femur

2. Medially rotates femur

3. Helps steady pelvic bone when opposite foot is raised off ground

What is the nerve supply of the gluteus medius?

Superior gluteal nerve

What is the origin fo the gluteus minimus?

External surface of the ilium between the anterior and inferior gluteal lines

What is the insertion of the gluteus minimus?

Greater trochanter/femur

What actions does the gluteus minimus carry out?

1. Abducts femur

2. Medially rotates demur

3. Helps steady pelvic bone when opposite foot is rasied off ground

What is the nerve supply of the gluteus minimus?

Superior gluteal nerve

What is the origin of the piriformis?

Anterior surface/sacrum

What is the insertion of the piriformis?

Greater trochanter/femur

What action does the piriformis carry out?

Laterally rotates femur

What is the nerve supply of the piriformis?

S1, S2

What is the origin of the superior gemellus?

Spine/Ischium

What is the insertion of the superior gemellus?

Greater trochanter/femur

What action does the superior gemellus carry out?

Laterally rotates femur

What is the nerve supply of the superior gemellus?

L4, L5, S1, S2

What is the origin of the obturator internus?

Internal surface/obturator membrane

What is the insertion of the obturator internus?

Greater trochanter/femur

What action does the obturator internus carry out?

Laterally rotates femur

What is the nerve supply of the obturator internus?

L4, L5, S1, S2

What is the origin of the inferior gemellus?

Ischial tuberosity

What is the insertion of the inferior gemellus?

Greater trochanter/femur

What action does the inferior gemellus carry out?

Laterally rotates femur

What is the nerve supply of the inferior gemellus?

L4, L5, S1, S2

What is the origin of the obturator externus?

External surface/obturator membrane

What is the insertion of the obturator externus?

Trochanteric fossa/femur

What action does the obturator externus carry out?

Laterally rotates femur

What is the nerve supply of the obturator externus?

Obturator nerve

What is the origin of the quadratus femoris?

Ischial tuberosity

What is the insertion of the quadratus femoris?

Quadrate tubercle/femur

What action does the quadratus femoris carry out?

Laterally rotates femur

What is the nerve supply of the quadratus femoris?

L4, L5, S1, S2

What are the posterior thigh muscles (hamstrings)?

1. Semitendinosus

2. Semimembranosus

3. Biceps Femoris: long head and short head

What is the origin of the semitendinosus?

Ischial tuberosity

What are the insertions of the semitendinosus?

1. Medial condyle/tibia

2. Proximal posterior shaft/tibia

What actions does the semitendinosus carry out?

1. Flexion of the leg at the knee

2. Stabilizes hip

3. Extends femur

4. Medially rotates leg

What is the nerve supply of the semitendinosus?

Sciatic nerve

What is the origin of the semimembranosus?

Ischial tuberosity

What is the insertion of the semimembranosus?

Medial condyle/tibia

What actions does the semimembranosus carry out?

1. Flexion of the leg at the knee

2. Stabilizes hip

3. Extends femur

4. Medially rotates leg

What is the nerve supply of the semimembranosus?

Sciatic nerve

What is the origin of the long head of the biceps femoris?

Ischial tuberosity

What are the insertions of the long head of the biceps femoris?

1. Head/fibula

2. Lateral condyle/tibia

What actions does the long head of the biceps brachii carry out?

1. Flexion of the leg at the knee

2. Stabilizes hip

3. Extends femur

4. Laterally rotates leg

What is the nerve supply to the long head of the biceps femoris?

Sciatic nerve

What is the origin of the short head of the biceps femoris?

Linea aspera/femur

What is the insertion of the short head of the biceps femoris?

Head/Fibula

What actions does the short head of the biceps femoris carry out?

1. Flexion of the leg at the knee

2. Laterally rotates leg

What is the nerve supply of the short head of the biceps femoris?

Sciatic nerve