Part 1: Muscle of Hip

Question 1

Iliopsoas

Answer 1

Origin: Iliacus: iliac fossa;
Psoas major: bodies and transverse processes of lumbar vertebrae

Insertion: Lesser trochanter of femur

Action: Flexion of the thigh at the hip joint

Innervation: Femoral nerve (L2-L4)

Blood Supply: Branches of the iliolumbar artery and medial femoral circumflex artery

Question 2

Iliacus

Answer 2

Origin: Iliac fossa of the ilium, iliac crest, Ala of sacrum

Insertion: Lesser trochanter of the femur (along with the tendon of the psoas major)

Action: Flexion of the thigh at the hip joint; assists in stabilizing the hip joint

Innervation: Femoral nerve
(specifically branches from the lumbar plexus, primarily L2-L4)

Blood Supply: Branches of the iliolumbar artery and medial femoral circumflex artery

Question 3

Psoas Major

Answer 3

Origin: Bodies and transverse processes of the lumbar vertebrae (T12-L5)

Insertion: Along with iliacus, inserts at the lesser trochanter of the femur via a common tendon (iliopsoas tendon)

Action: Flexion of the thigh at the hip joint, contributes to lateral bending of the trunk

Innervation: Anterior rami of lumbar nerves, specifically branches from L1-L3 forming part of the lumbar plexus

Blood Supply: Subcostal a., lumbar aa.

Question 4

Psoas Minor

Answer 4

Origin: Generally arises from the sides of T12 and L1 vertebrae

Insertion: Tendon of the psoas major or the iliopectineal eminence

Action: flexes & laterally bends the lumbar vertebral column.
Absent in 40% of cases in population.

Innervation: Variable, often innervated by branches of the lumbar plexus (usually from L1-L2)

Blood Supply: Supplied by branches from the lumbar arteries

Question 5

Obturator Internus

Answer 5

Origin: Internal surface of the obturator membrane, obturator foramen and margin of the obturator foramen

Insertion: Medial surface of the greater trochanter of the femur (via tendon passing through the lesser sciatic foramen)

Action: Lateral rotation and abducts the thigh

Innervation: Nerve to obturator internus muscle (a branch of the sacral plexus, specifically from spinal nerves L5-S2)

Blood Supply: obturator a.

Question 6

Obturator Externus

Answer 6

Origin: External surface of the obturator membrane and and the superior and inferior pubic rami

Insertion: Trochanteric fossa of the femur

Action: Lateral rotation and stabilization of the hip joint

Innervation: Obturator nerve (L2-L4)

Blood Supply: Branches from the obturator artery

Question 7

Pectineus

Answer 7

Origin: pecten of the pubis

Insertion: Pectineal line of the femur (near the lesser trochanter)

Action: Flexion and adduction of the thigh at the hip joint; assists in medial rotation

Innervation: Femoral nerve (L2-L4)

Blood Supply: medial femoral circumflex a.

Question 8

Piriformis

Answer 8

Origin: Anterior surface of the sacrum

Insertion: Greater trochanter of the femur

Action: External rotation and abduction of the thigh at the hip joint

Innervation: ventral rami of S1-S2

Blood Supply: Branches of the superior gluteal artery

Question 9

Quadratus Femoris

Answer 9

Origin: Ischial tuberosity (part of the pelvis)

Insertion: Quadrate line of the femur (located below the intertrochanteric crest)

Action: Lateral rotation and stabilization of the hip joint

Innervation: Nerve to quadratus femoris m (a branch of the sacral plexus, specifically from spinal nerves L4-S1)

Blood Supply: Branches from the inferior gluteal

Question 10

Gluteus Maximus

Answer 10

Origin: Posterior ilium (gluteal line), sacrum, and coccyx

Insertion: upper - iliotibial tract
lower- Gluteal tuberosity of femur

Action: Extension and lateral rotation of the thigh at the hip joint

Innervation: Inferior gluteal nerve (L5-S2)

Blood Supply: Superior and inferior gluteal arteries

Question 11

Gluteus Medius

Answer 11

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

Insertion: Greater trochanter of femur

Action: Abduction and medial rotation of the thigh at the hip joint

Innervation: Superior gluteal nerve (L4-S1)

Blood Supply: Superior gluteal artery

Question 12

Gluteus Minimus

Answer 12

Origin: External surface of ilium

Insertion: Anterior surface of greater trochanter of femur

Action: Abduction and medial rotation of the thigh at the hip joint

Innervation: Superior gluteal nerve (L4-S1)

Blood Supply: Superior gluteal artery

Question 13

Gemellus, superior

Answer 13

Origin: ischial spine

Insertion: obturator internus tendon

Action: laterally rotates the femur

Innervation: nerve to the obturator internus m.

Blood Supply: inferior gluteal a.

Question 14

Gemellus, inferior

Answer 14

Origin: ischial tuberosity

Insertion: obturator internus tendon

Action: laterally rotates the femur

Innervation: nerve to the quadratus femoris m.

Blood Supply: inferior gluteal a.

Question 15

Tensor Fasciae Latae

Answer 15

Origin: Anterior iliac crest and anterior superior iliac spine

Insertion: Iliotibial tract

Action: Flexion, abduction, and medial rotation of the thigh at the hip joint; tenses iliotibial tract

Innervation: Superior gluteal nerve (L4-L5)

Blood Supply: Branches of the superior gluteal artery

Question 16

Iliotibial Tract (IT Band)

Answer 16

Function: Helps stabilize the knee and lateral thigh muscles during movement