Lower Limb: Muscles of thigh

Question 1

What is the significance of the compartments of the thigh?

Answer 1

Compartments are separated by bone, fascia & interosseous membrane
Anterior = extensors = extend the knee & flex hip
Posterior = flexors = act on hip & knee
Medial = adductors = act mostly on the hip

Question 2

What is the deep fascia of the thigh & what is its signficance?

Answer 2

Fascia lata
extends from pelvic girdle above and is continuous with deep fascia of the leg below
Invests thigh muscles like a stocking - prevents bulging on contraction & aids venous return

Question 3

What is the iliotibial tract?

Answer 3

Lateral thickening of the fascia lata
Functions like a tendon
The aponeurotic tendons of glut max (posteriorly) and the tensor fascia lata (anteriorly) blend with it

Question 4

What is the significance of the gluteal region?

Answer 4

Muscles extend, rotate & abduct the thigh at the hip

hold the pelvis level in locomotion

Question 5

What movements do the gluteal muscles perform in relation to the HJ?

Answer 5

All ABDUCT
Glut max only extends
Glut max lateral rotation
Glut min + med medial rotation

Question 6

What movements at the HJ are piriformis + obtrurator interns perform?

Answer 6

abduct + lateral rotation

Same as glut max, minus extension

Question 7

Origin, insertion & function of tensor fascia lata

Answer 7

Pelvic girdle to the become continuous with the iliotibial tract which runs down the lateral side of the thigh
Limits outward building of muscles
flexes, abducts & medially rotates

Question 8

Origin, insertion & function of Gluteus Maximus

Answer 8

Superficial muscle covers all muscles of gluteal region
Arises from the dorsum of the sacrum, lateral part of coccyx & external surface of the ilium (beyond the posterior gluteal line)
Attaches to the gluteal tuberosity of proximal femur

Extension of HJ, abduction & lateral rotation

Question 9

Origin, insertion & function of gluteus medius

Answer 9

Deep to Glut max
Arises from external surface of ilium, between anterior & posterior gluteal lines
Attaches to lateral side of greater trochanter (femur)

Abducts, medially rotates HJ

Question 10

Origin, insertion & function of gluteus minimus

Answer 10

deep to glut max
arises from outer surface of ilium below posterior gluteal line (below medius)
attaches to lateral part of greater trochanter (femur)

Medial rotation & abduction of hip

Question 11

Origin, insertion & function of Piriformis

Answer 11

Arises within the pelvis from the anterior aspect of the sacrum
Exits pelvis through the greater sciatic notch & attaches to the medial part of the greater trochanter

Lateral rotation & abduction of HJ

Question 12

Origin, insertion & function of Obtrurator internus

Answer 12

Arises within pelvis from outer margins of the obtrurator foramen & internal aspect of obtrurator membrane
Exits through the lesser sciatic notch into the gluteal region
(Takes 2 gemelli muscles with it)
Attaches to medial part of greater trochanter (femur)

Abduct and laterally rotates HJ (aided by germilli muscles)

Question 13

Origin, insertion & function of quadrates femoris

Answer 13

Arises from lateral aspect of ischium & inserts into proximal medial aspect femur
Lateral rotation only

Question 14

What are the quadriceps muscles? Which are superficial & deep?

Answer 14

Superficial - Vastus lateralis, vastus medialis & rectus femoris
Deep - vastus intermedius

Question 15

Where do the three vastus quadricep muscles originate?

Answer 15

The femur
Lateralis & medialis have a continuous attachment beginning at the intertrochanteric line
Intermedius is a deep muscle so arises from upper 2/3s of the shaft of femur

Question 16

What is the origin of rectus femoris?

Answer 16

2 origins
1st from the AIIS
2nd just above acetabulum

Question 17

What is the common insertion of the quadricep muscles?

Answer 17

Common tendon which crosses the knee joint & contains the patella bone (sesamoid bone) and then changes its name to the patella ligament to insert into the tibial tuberosity

Question 18

What is different about rectus femoris compared to vastus quadriceps?

Answer 18

Rectus femurs has 2 origins compared to 1
Originates higher and crosses the hip joint, therefore ALSO acts to move (flex) the hip, others only cross knee joint & extend it

Question 19

What common movement does the quadriceps perform?

Answer 19

Extension of the knee

Question 20

What components of quadriceps have another INSERTION, other than quads tendon?

Answer 20

Vastus lateralis & medialis - insert into the respective sides of the patella

Question 21

What prevents the patella laterally displacing during quadricep contraction?

Answer 21

Vastus medialis also inserts into the the medial margin of the patella
Reinforces capsule & prevents lateral dislocation of the patella when the quadriceps contract
Lateral femoral condyle also prevents dislocation

Question 22

What are the muscles of the anterior compartment of the thigh?

Answer 22

Psoas major, iliacus, sartorius & quadriceps

Question 23

Origin, insertion & function of psoas major

Answer 23

arises from posterior abdo wall from T12 - L5 vertebrae
Common tendon insertion with iliacus (iliopsoas) into the lesser trochanter
flexes the hip & maintains lumbar lordosis in standing

Question 24

Origin, insertion & function of iliacus

Answer 24

Arises from iliac fossa
Common tendon insertion with PM - lesser trochanter
Flexes HJ & maintains lumbar lordosis in standing

Question 25

Origin, insertion & function of sartorius

Answer 25

ASIS of ilium and inserts onto tibia (inferiomedial to tibial tuberosity) Important when sitting cross legged + has a synergistic effect with other muscles to help flex the HJ & extend the knee

Question 26

Difference in insertions between muscles of gluteal region & muscles of anterior compartment of thigh

Answer 26

Gluteal - greater trochanter | Anterior - lesser trochanter or tibial tuberosity

Question 27

What is the main function of the muscles of the medial compartment of the thigh? What are the muscles?

Answer 27

Adduction at the HJ Gracilis pectineus adductor longus, brevis & magnus

Question 28

What are the 3 adductor muscles from superficial to deep?

Answer 28

Adductor longus, brevis & magnus

Question 29

Origin, insertion & function of gracilis

Answer 29

Body of pubis and inferior aspect of pubic rami to the medial surface of the proximal tibia Long and slender Only one which crosses the Hip and knee joint - adduction of HJ + flexion at knee

Question 30

Origin, insertion & function of pectineus

Answer 30

Origin along pectineal line and adjacent part of the body of the pubic bone to the base of the lesser trochanter along the linea aspra (posterior aspect of femur) Adduction of HJ

Question 31

Where do the 3 adductor muscles collectively originate & insert?

Answer 31

extend from the inferior pubic ramus and insert along the linear aspra (at various lengths)

Question 32

What is special about adductor magnus?

Answer 32

It is the most expensive & deepest of the 3 named adductor muscles It has an adductor and hamstring component, therefore 2 origins & 2 insertions Normal adductor origin & insertion (inferior pubic rams along linea aspra - extends further than other two) Hamstring origin from ischial tuberosity (with other hamstrings) to the adductor tubercle

Question 33

What is the adductor hiatus?

Answer 33

Gap between the two insertions of adductor magnus between the distal linea aspra and the adductor tubercle which allows passage of vessels

Question 34

What movements do the 3 named adductor muscles permit?

Answer 34

All adduct the HJ | Longus & magnus also medially rotate

Question 35

What are the muscles of the posterior compartment?

Answer 35

Hamstrings: | biceps femoris, semitendinosus ad semimembranosus

Question 36

What is the common origin of the hamstrings?

Answer 36

Ischial tuberosity

Question 37

What hamstring has a 2nd origin to the common origin?

Answer 37

Biceps femoris long head arises at ischial tuberosity (common) SHORT head arises at lateral tip of linear aspra

Question 38

What are the insertions of the hamstrings?

Answer 38

Biceps femoris inserts LATERALLY to head of fibula Both semi's insert MEDIALLY Semitendinosus to medial aspect of proximal tibia Semimemrbanosus inserts into medioposterior surface of the medial condyle of tibia

Question 39

What is significant about the insertion of semimembranosus?

Answer 39

It is part of PES ANSERINUS - common tendon that blends into capsule of medial tibia Sartorius, gracilis & semimembranosus

Question 40

What movements do the hamstrings permit?

Answer 40

Flex the KNEE Extend the HIP Biceps femoris LATERALLY rotates and semi's MEDIALLY rotate