Posterior lower extremity and Hip

Question 1

sacroiliac joint

Answer 1

• the joint between the sacrum and ilium
• It is a highly-stable joint capable of only a small amount of gliding movement.
• This is where the lower extremity meets the spinal column

Question 2

pubic symphysis

Answer 2

is located between the right and left pubic bones. There is a thick fibrocartilaginous disc between the two pelvic bones at this location.

Question 3

coxal hip joint

Answer 3

• contains the acetabulum
• contains the iliofemoral, ischiofemoral, and pubofemoral ligaments
• also contains the ligamentum teres

Question 4

ligamentum teres

Answer 4

• this is the ligament to the head of the femur

- contains the artery to the head of the femur

Question 5

gluteus maximus

Answer 5

largest and most superficial of the gluteal muscles
- this Extends, laterally rotates, and abducts the hip
- inserts onto the iliotibial tract and the gluteal tuberosity of femur
innervated by inferior gluteal nerve

Question 6

gluteus medius

Answer 6

• this is just deep to the gluteus maximus
• this Abducts and medially rotates hip
• this inserts at the Greater trochanter of femur

Question 7

gluteus minimus

Answer 7

this is the deepest and smallest of the gluteal muscles

• this Abducts and medially rotates hip
• this inserts at the Greater trochanter of femur

Question 8

piriformis

Answer 8

an important lateral rotator of the hip

Question 9

hamstring muscles

Answer 9

• what the muscles of the posterior thigh are collectively called
• they originate at the ischial tuberosity
• they travel to the medial aspect of the knee
• made of the semitendinosus, the semimembranosus, and the long head of the biceps formis

Question 10

semitendinosus

Answer 10

• a thinner muscle belly and a longer tendon than the semimembranosus
• It sits just superficial to the semimembranosus
• the long tendon at the inferior side wraps around the knee on the medial side
• extends the hip
• rotates the knee medially
• flexes the knee
• origin: ischial tuberosity
• insertion: pes anserine insertion

Question 11

semimembranosus

Answer 11

• this has a thicker muscle belly and a shorter tendon than the semitendinosus
• this is more medial and deep than the semitendinosus
• extends the hip
• rotates the knee medially
• flexes the knee

Question 12

biceps femoris

Answer 12

• has two heads
• the long head and the short head
• the long head is superficial to the long head
• the two heads merge together and insert onto the head of the fibula together
• lateral to the semimembranosis and the semitendinosis
• both cause lateral rotation of the knee and flexion of the knee
• the long head causes hip extension

Question 13

the long head of the biceps femoris

Answer 13

• this orginates on the ischial tuberosity
• insert onto the fibular head after merging with the short head to form a common tendon
• extends the hip
• works with the short head to flex, and laterally rotate the knee

Question 14

short head of the biceps femoris

Answer 14

• this originates on the linea aspera
• insert onto the fibular head after merging with the long head to form a common tendon
• causes lateral knee roation
• causes hip flexion

Question 15

what is part of the gluteal region

Answer 15

• gluteus maximus
• gluteus medius
• gluteus minimus
• piriformis

Question 16

gastrocnemius

Answer 16

• the most superficial posterior leg muscle
• aids in knee flexion
• it is the primary plantarflexar of the foot
• it’s tendon merges with the soleus’ tendon to insert on the calcaneus bone of the foot

Question 17

soleus

Answer 17

• sits deep to the gastrocnemius
• inserts on the calcaneus in the calcaneal tendon
• innervated by the tibial nerve
• plantarflexion of the ankle

Question 18

calcaneal tendon

Answer 18

• the achilles tendon
• this is where the gastrocnemius and the soleus tendons merge
• this inserts onto the calcaneus bone of the foot

Question 19

plantaris

Answer 19

a small muscle with a tiny muscle belly deep to the gastrocnemius

• not present in all individuals
• this is going across the posterior knee
• has a long thin tendon that travels inferiorly to insert on the calcaneus
• weak knee flexor and weak ankle plantarflexor

Question 20

superficial posterior compartment of the leg

Answer 20

• this includes the gastrocenemius, soleus, the calcaneal tendon and the plantaris

Question 21

deep posterior compartment of the leg

Answer 21

• four muscles:
• tibialis posterior
• flexor digitorum longus
• flexor hallucis longus
• popliteus
• *these are all innervated by the tibial nerve

Question 22

tibialis posterior

Answer 22

this runs along the posterior aspect of the tibia

• this is lateral to flexor digitorum longus and medial to flexor hallucis longus
• its tendon crosses under flexor digitorum longus meaning that it crosses the medial malleolus the most anterior
• plantarflexion of the ankle and inverts the ankle

Question 23

flexor digitorum longus

Answer 23

• these are the tendons that extend to the 2-5 digits
• this is the most medial of the three muscles in this layer and its tendon passes the medial malleolus in the middle of the other two tendons
• plantarflexion and weak inversion of the ankle
• flexes the MTP, PIP, and the DIP joints in the toes

Question 24

flexor hallucis longus

Answer 24

• its tendon wraps around the medial aspect of the ankle before it reaches the distal great toe
• its tendon wraps around the medial malleolus the most posterior of three
• long path gives the muscle a mechanical advantage and makes it a powerful flexor of the first digit
• plantarflexion and weak inversion of the ankle

Question 25

what is Tom, Dick, AN Harry important for

Answer 25

The muscles Tibialis posterior, flexor Digitorum longus, and flexor Hallucis longus usually travel in a specific order around the medial malleolus - the AN stands for posterior tibial Artery and tibial Nerve - the tibialis posterior is the most anterior/superior and the flexor hallucis is the most posterior/inferior

Question 26

popliteus

Answer 26

- difficult to see on the tissue -It sits on the superior aspect of the tibia and crosses the knee joint - It functions to medially rotate the tibia and “unlock” the knee from full extension in the first few degrees of flexion. - knee flexion innervated by tibial nerve

Question 27

intrinsic foot muscles

Answer 27

muscles that act on the foot and are entirely located within the foot

Question 28

plantar fascia

Answer 28

- This thick layer of fascia is superficial to the muscles of the plantar aspect of the foot - attaches to the calcaneus in anatomical position

Question 29

Plantar muscles layer 1

Answer 29

- flexor digitorum brevis - abductor hallucis - abductor digiti minimi

Question 30

flexor digitorum brevis

Answer 30

the muscle deep to the plantar fascia and flexes digits 2-4 -this is in the middle of the plantar aspect of the foot and has a big muscle body that then has tendond that branch out to the digits

Question 31

abductor hallucis

Answer 31

the large muscle on the medial aspect of the great toe - it abducts the great toe - innervated by the medial plantar nerve

Question 32

abductor digiti minimi

Answer 32

located on the lateral aspect of the 5th digit - abducts the 5th digit - innervated by the lateral plantar nerve

Question 33

Plantar muscles layer 2

Answer 33

muscles of this layer attach to the tendon of flexor digitorum longus - Quadratus plantae - lumbricals

Question 34

Quadratus plantae

Answer 34

- this runs from the calcaneus to the tendons of flexor digitorum longus - adjusts the angle of pull on these tendons - aligns these tendons so that the toes flex within the sagittal plane

Question 35

lumbricals

Answer 35

- insert on to the flexor digitorum longus tendons - in between the different branches of that tendon - flex the MP and extend the PIP and DIP joints - the first lumbircal is innervated by the medial plantar nerve but the rest are innervated by the lateral plantar nerve

Question 36

Plantar muscles Layer 3

Answer 36

- adductor hallucis - flexor hallucis brevis - flexor digiti minimi

Question 37

adductor hallucis

Answer 37

- 7 shaped - has transverse and oblique heads - adducts the great toe

Question 38

flexor hallucis brevis

Answer 38

flexes the great toe - lives completely within the foot - lies along the medial side of the plantar aspect

Question 39

flexor digiti minimi brevis

Answer 39

flexes the fifth digit - lives completely in the foot - lies along the lateral side of the planter aspect - a small muscle that is medial to the abductor digiti minimi

Question 40

plantar muscles layer 4

Answer 40

- the deepest layer of muscles on the plantar aspect of the foot - dorsal interossei - plantar interossei

Question 41

Dorsal interossei

Answer 41

Abduct the toes - the bellies of these muscles are on the outside of the toes (between the metatarsal bones) - these can be seen from the plantar side and the dorsal aspect of the foot

Question 42

Plantar interossei

Answer 42

Adduct the toes - appear to only be on toes 3-5 and are on the medial side of the meditarsal - can be seen from the plantar side of the foot

Question 43

what is DAB and PAD

Answer 43

this is a pnemonic to help remeber that the Dorsal interossei ABduct the toes and the plantar interossei ADDuct the toes

Question 44

what innervates the gluteus maximus

Answer 44

inferior gluteal nerve

Question 45

what innervates the gluteus medius

Answer 45

the superior gluteal nerve

Question 46

what innervates the gluteus minimus

Answer 46

the superior gluteal nerve

Question 47

what are the lateral rotators of the hip

Answer 47

``` piriformis Quadratus Femoris Superior Gemellus Inferior Gemellus Obturator Internus Obturator Externus ```

Question 48

what innervates the posterior thigh muscles

Answer 48

- the tibial division of the sciatic nerve innervates long head, the semimembranosis, and the semitendinosis - the short head is innervated by the common fibular nerve

Question 49

what does the long head of the biceps femoris do

Answer 49

- this extends the hip - flexes and laterally rotates the knee - inserts at the head of the fibula - originates at the ischial tuberosity

Question 50

what does the short head of the biceps femoris do

Answer 50

- flexes and laterally rotates knee - originates at the linea aspera - inserts on the head of the fibula

Question 51

what do the semimembranosis and the semitendinosus do?

Answer 51

- they Extend the hip and flexes knee; medially rotates knee | - they originate at the ischial tuberosity

Question 52

where does the semitendinosis insert

Answer 52

pes anserine insertion

Question 53

the gastrocnumius, soleus, and the plantaris are innervated by what

Answer 53

the tibial nerve

Question 54

what does the medial plantar nerve innervate

Answer 54

- abductor hallucis - flexor hallicus brevis - flexor digitorum brevis - 1st lumbrical

Question 55

what does the lateral plantar nerve innervate

Answer 55

- the adductor hallicus (7 muscle) - flexor digiti minimi brevis - dorsal interossei - abductor digiti minimi - quadratus plantae - 2nd- 4th lumbricals