Lecture 8: The Lower Limb

Question 1

Each side of the pelvis is made up of 3 bones that are fused together, which reflects what latin name?

Answer 1

Os Coxae

Question 2

Of the bones of the lower limb that are paired, which is considered weight bearing and which is more associated with attachment for muscle?

Answer 2

Weight bearing = tibia

Muscle attachment = fibula

Question 3

What type of bone is the patella?

Answer 3

Sesamoid bone = a bone embedded in a tendon

Question 4

The patella is what allows for complete ____________ of the lower limb. It also has a tendency to slide ____________

Answer 4

Extension

Laterally

Question 5

Thickened parts of the fibrous articular capsule associated with the hip joint are called ______________ ligaments

Answer 5

Intrinsic

Question 6

What are the 3 hip joint intrinsic ligaments?

Answer 6

Iliofemoral ligament
Pubofemoral ligament
Ischiofemoral ligament

Question 7

Name the 3 gluteal muscles

Answer 7

Gluteus maximus
Gluteus medius
Gluteus minimus

Question 8

What muscle is enclosed by fascia, is found at the lateral thigh, and functions to abduct, medically rotate, and flex the thigh?

Answer 8

Tensor fascia lata

Question 9

What is the IT band?

Answer 9

Distinct feature of the fascia lata = iliotibial tract

Question 10

Where is the pririformis located?

Answer 10

Deep to the gluteus maximus and medial to gluteus medius

Question 11

What muscle leaves the pelvis through the lesser sciatic foramen and what muscle does it pair with?

Answer 11

Obturator internus

Obturator externus

Question 12

Where is the quadratus femoris muscle located?

Answer 12

Deep gluteal region, inferior to gluteus medius and minimus

Question 13

Describe the evolution of the Os Coxae (pelvis)

Answer 13

Pelvis becomes more stable and bones become reshaped and rearranged to allow for greater stability and differences in weight bearing

Question 14

In comparing the shift from chimp to human pelvis: the ilium is reoriented, the shape of the pelvic inlet/outlet have changed, and the size of the ___________ increases because we bear all weight on hind limbs

Answer 14

Acetabulum

Question 15

In comparing pelvis and standing posture in gorillas and humans, gorillas have longer _________ and ______ which provide a mechanical advantage for climbing.

Answer 15

Ischium

Ilium

Question 16

Describe the differences in the intrinsic capsular ligaments of the human hip as compared to chimps

Answer 16

The capsular hip ligaments become taught at a higher degree of extension in humans than in quadrupedal primates

Question 17

The primate gluteus maximus extends much further down the femur in chimps than in humans. What function does the gluteus maximus serve in other primates that it does not do much of in humans?

Answer 17

Abductor

Question 18

The muscle that contributes the most in our gluteal region is the _______________, while in chimps and gorillas it is the ______________

Answer 18

Gluteus maximus

Gluteus medius

Question 19

In contrast to the cruciate/intracapsular ligaments, there are 5 extrapsular (external) knee joint ligaments that consist of:

Answer 19

Patellar ligament
Fibular collateral ligament
Tibial collateral ligament (intrinsic)
Oblique popliteal ligament (intrinsic)
Arcuate popliteal ligament

[Intrinsic = thickened capsule]

Question 20

What are cruciate ligaments/where are they located?

Answer 20

Intraarticular knee joint ligaments - found in the knee

Anterior cruciate ligament
Posterior cruciate ligament

Question 21

What is the longest muscle and where is it found?

Answer 21

Sartorius, thigh

Question 22

What muscles of the thigh make up the quadriceps femoris?

Answer 22

Vastus lateralis
Rectus femoris
Vastus medialis
Vastus intermedius

Question 23

What muscles make up the superficial medial thigh (adductors)?

Answer 23

Pectineus
Adductor longus
Adductor brevis
Gracilis

Question 24

What muscles make up the deep medial thigh?

Answer 24

Obturator externus

Adductor magnus

Question 25

What are the posterior thigh muscles?

Answer 25

Biceps femoris Semitendinosus Semimembranosus Gracilis

Question 26

When people say "hamstrings" what muscle are they referring to?

Answer 26

Adductor magnus

Question 27

Compare the carry angle of the femur in gorillas vs. humans

Answer 27

Gorillas: straight, feet are placed further from midline Humans: angled, places feet closer to midline for bipedal gait

Question 28

The repositioning of human thigh muscles through evolution were needed to counteract the increased carry angle of the femur. What muscle adaptation counters the lateral glide of the patella due to this increased carry angle?

Answer 28

Distal extension of the vastus medialis

Question 29

What aspect of patellar bone structure related to increased carry angle of the femur is found in humans and australopithecines but not in chimpanzees?

Answer 29

Patellar notch

Question 30

What is considered to be the true ankle joint?

Answer 30

Talocrural joint

Question 31

What joint in the foot is located most proximal to the ankle?

Answer 31

Transverse tarsal joint

Question 32

What joint is found where the talus rests on the calcaneus of the foot? What supports the fibrous capsule?

Answer 32

Subtalar (talocalcanean) joint | Interosseus talocalcaneal ligament

Question 33

These four parts make up what ligament: Anterior tibiotalar part Tibionavicular part Tibiocalcaneal part Posterior tibiotalar part

Answer 33

Deltoid ligament in the ankle (aka medial)

Question 34

The plantar calcaneonavicular ligament and medial (deltoid) ligaments are found where?

Answer 34

Ankle/foot

Question 35

The lateral ligaments of the foot and ankle consist of what 3 discrete ligaments attaching lateral malleolus to talus and calcaneus?

Answer 35

Anterior talofibular ligament Posterior tibiofibular ligament Anterior tibiofibular ligament

Question 36

What is the name of the long, thick muscle on the anterolateral surface of the tibia?

Answer 36

Tibialis anterior

Question 37

What muscle is responsible for extending the lateral four toe digits?

Answer 37

Extensor digitorum longus

Question 38

What muscle fuses with the digitorum longus proximal in the foot but is only variably present?

Answer 38

Fibularis tertius

Question 39

What muscle is responsible for extending the big toe?

Answer 39

Extensor hallucis longus

Question 40

What relatively large muscle extends the entire lateral side of the fibula?

Answer 40

Fibularis longus

Question 41

What muscle is deep to fibularis longus?

Answer 41

Fibularis brevis

Question 42

What are the muscles of the posterior compartment?

Answer 42

Gastrocnemius Soleus Plantaris

Question 43

What are the four deep posterior muscles of the crural compartment?

Answer 43

Popliteus Flexor hallucis longus Flexor digitorum longus Tibialis posterior

Question 44

What aspect of triceps surae is indicative of a more limited range of movement in humans compared to chimps?

Answer 44

Shorter muscle bellies; also note that the soleus origin is more extensive in humans

Question 45

What is the difference in function of the tibialis anterior and fibularis longus between chimps and humans?

Answer 45

Chimps: permit midtarsal break (flexibility) Humans: enhance midtarsal stability (rigidity)

Question 46

Describe the variation in extant hominid digital flexors in the great apes vs. humans

Answer 46

Great apes = flexor digitorum tibialis and fibularis Humans = flexor hallucis longus Only one muscle in humans, so we have less dexterity with our toes

Question 47

What two muscles make up the dorsum of the foot?

Answer 47

Extensor hallucis brevis | Extensor digitorum brevis

Question 48

What are the 3 plantar muscles that extend from the calcaneus to phalanges? (First layer)

Answer 48

Abductor digiti minimi Flexor digitorum brevis Abductor hallucis

Question 49

What 2 plantar muscles make up the second layer?

Answer 49

Quadratus plantae | Lumbricals

Question 50

What 3 plantar muscles are found in the third layer?

Answer 50

Flexor digiti minimi brevis Adductor hallucis Flexor hallucis brevis

Question 51

What plantar muscles make up the fourth layer?

Answer 51

3 plantar interossei | 4 dorsal interossei

Question 52

Describe the variation in the flexor digitorum brevis (small flexor in the foot) between great apes and humans; what does this mean for humans?

Answer 52

Great apes: FDB originates on the tendon Humans: FDB originates on the calcaneus Humans are able to "toe-off" more powerfully

Question 53

Describe the types of movement possible in the subtalar and transverse tarsal joints

Answer 53

Inversion/eversion between talus and calcaneus Endorotation/exorotation at transverse tarsal joint

Question 54

In human primates, the midaxis of the foot is the _____ digit which is termed ___________. In non-human primates, the midaxis is the ________ digit, which is termed ____________.

Answer 54

Third Mesaxonic Second Entaxonic

Question 55

The metatarsal phalangeal break is indicative of the ________ foot. This is indicated by hyperextension in the ______ of the foot, and rigidity in the _____ region

Answer 55

Human Arch Toe

Question 56

Describe the "Windlass" effect on plantar fascia

Answer 56

The fascia is pulled taught when toeing off using the MP joint as a windlass/pully

Question 57

Who has a bigger calcaneus, chimps or humans? Why?

Answer 57

Humans, because we step with our heels, not the forefoot like chimps do

Question 58

In terms of flexibility vs. rigidity at the midtarsal joint, there is greater ________ with calcaneal inversion, and greater __________ with calcaneal eversion.

Answer 58

Rigidity | Flexibility

Question 59

In terms of flexibility/rigidity: More continuous surface area in subtalar joint articular surfaces may be indicative of more ___________ while less is indicative of greater _____________.

Answer 59

Flexibility | Rigidity

Question 60

In terms of variation in flexor digitorum brevis among extant primates, humans have 100% origination off the _____________, which means that we have _______ power with toeing off than with origination off of a tendon

Answer 60

Calcaneus | More

Question 61

General mammalian characteristics of the lower limb include: Expansion of the _______ attachment of pelvis Femoral neck at sharp angle to _________ Limb joints operating in a single __________

Answer 61

Sacral Shaft Plane

Question 62

General primate characteristics of the lower limb include: Tendency for __________ posture of the trunk ______________ hallux

Answer 62

Upright | Opposable

Question 63

General hominoid characteristics of the lower limb include: Iliac blade flaring widely in _________ plane Subtalar and transverse joints of foot ________ Digits elongated; _______ toe longest Development of inferior process of heel _______

Answer 63

Coronal Mobile Second Tubercle

Question 64

General human characteristics of the lower limb include: Sacrum wide and ________ inferiorly SI joint closer to __________ Iliac ______ strengthens the ilium for stresses of abduction Gluteus _________ reoriented as extensor of hip Gluteus medius and minimus and tensor fasciae latae reoriented as __________ Medial ___________ arch present in foot Hallux permanently __________ parallel with other digits

Answer 64

``` Narrows Acetabulum Pillar Maximus Abductors Longitudinal Adducted ```