Musculoskeletal Anatomy - Lower Limb

Question 1

what are the two superficial veins draining the lower leg?

Answer 1

great saphenous vein

small saphenous vein

Question 2

which superficial vein of the lower leg ascends anteriorly to the medial malleolus?

Answer 2

great saphenous vein

Question 3

which superficial vein of the lower leg ascends posteriorly to the lateral malleolus?

Answer 3

small saphenous vein

Question 4

where does the great saphenous vein drain, and into which vein?

Answer 4

it drains into the femoral vein in the inguinal region

Question 5

where does the small saphenous vein drain, and into which vein?

Answer 5

it drains into the popliteal vein in the popliteal fossa

Question 6

which superficial vein of the lower leg presents more commonly with varicose veins?

Answer 6

great saphenous vein

Question 7

what are the major groups of lymph nodes in the leg, and which veins are they associated with?

Answer 7

superficial inguinal nodes - great saphenous vein
deep inguinal nodes - femoral vein
popliteal nodes - small saphenous vein/popliteal vein

Question 8

what is the dermatome of the knee?

Answer 8

L3

Question 9

what is the dermatome of the big toe?

Answer 9

L5

Question 10

what is the dermatome of the little toe?

Answer 10

S1

Question 11

which artery is damaged in avascular necrosis of the hip?

Answer 11

medial circumflex femoral artery

Question 12

what are the boundaries of the femoral triangle?

Answer 12

inguinal ligament
sartorius muscle
adductor longus muscle

Question 13

what are the contents of the femoral triangle, lateral to medial?

Answer 13

femoral nerve
femoral artery
femoral vein
inguinal lymph nodes

Question 14

name the main flexors of the hip

Answer 14

iliacus/psoas major
pectineus
sartorius
rectus femoris
tensor fascia latae

Question 15

name the main extensors of the hip and their innervation

Answer 15

gluteus maximus
semitendinosus
semimembranosus
biceps femoris

Question 16

what is the cutaneous innervation of the sole of the foot?

Answer 16

medial plantar nerve
lateral plantar nerve
saphenous nerve
sural nerve
medial calcaneal nerve (branch of tibial)

Question 17

name the main abductors of the hip and their innervation

Answer 17

tensor fascia lata
gluteus medius
gluteus minimus

Question 18

name the main adductors of the hip

Answer 18

adductor brevis 
adductor longus 
adductor magnus
gracilis
pectineus

Question 19

name the main internal rotators of the hip

Answer 19

tensor fascia lata

anterior fibres of gluteus medius

Question 20

name the main external rotators of the hip

Answer 20

piriformis
obturator internus
obturator externus
gemelli (sup and inf)
quadratus femoris

Question 21

what is Shenton’s line, and what is its purpose?

Answer 21

line formed by superior pubic ramus and neck of femur

disruption in the line can indicate a neck of femur fracture

Question 22

what is the blood supply to the femoral head?

Answer 22

medial and lateral femoral circumflex arteries
obturator artery branch (via ligamentum teres of head of femur)
intramedullary blood supply

Question 23

what structure passes through the ligament of head of femur (ligamentum teres) and what is its significance?

Answer 23

branch of obturator artery - supplies head of femur

Question 24

the medial and lateral femoral circumflex arteries arise from which artery?

Answer 24

profunda femoris artery

Question 25

what is the surgical management of intracapsular and extracapsular hip fractures?

Answer 25

intracapsular - replacement (unless young/undisplaced, in which case fix) extracapsular - intramedullary nail fixation

Question 26

what is the main factor contributing to the difference in surgical management of intracapsular and extracapsular hip fractures?

Answer 26

whether the blood supply to the head of femur is compromised as a result of the fracture

Question 27

what is the purpose of the patella?

Answer 27

extension of the knee, acting as a lever for the quadriceps femoris

Question 28

what is the main extensor of the knee joint?

Answer 28

quadriceps femoris

Question 29

what are the main flexors of the knee joint?

Answer 29

``` semitendinosus semimembranosus biceps femoris sartorius gracilis popliteus (unlocks knee) ```

Question 30

what is the purpose of the popliteus muscle?

Answer 30

it unlocks knee before flexion

Question 31

what is the purpose of the menisci?

Answer 31

transmit load shock absorption proprioception stability

Question 32

what type of joint are the ankle joint and subtalar joint?

Answer 32

ankle joint - hinge | subtalar joint - plane

Question 33

during which joint movement is the ankle joint the most stable?

Answer 33

during dorsiflexion

Question 34

which joints in the foot are responsible for inversion and eversion?

Answer 34

subtalar joint | transverse tarsal joint

Question 35

what is the transverse tarsal joint made up of?

Answer 35

talo-navicular joint | calcaneo-cuboidal joint

Question 36

which muscles are responsible for inversion of the foot?

Answer 36

tibialis anterior | tibialis posterior

Question 37

which muscles are responsible for eversion of the foot?

Answer 37

fibularis longus | fibularis brevis

Question 38

what are the contributors to the arch form in the foot?

Answer 38

- long and short plantar ligaments - plantar aponeurosis - spring ligament (calcaneonavicular) - intrinsic foot tendons - shape of the bones

Question 39

what is a common cause of acquired flat feet?

Answer 39

posterior tibial muscle dysfunction

Question 40

what are the functions of the arches in the foot?

Answer 40

distribute weight shock absorption springboard for walking/jumping/running

Question 41

what are tarsal coalitions and where are they most commonly found?

Answer 41

tarsal bones becoming stuck to eachother | commonest are calcaneonavicular and talocalcaneal

Question 42

what are the most frequently found accessory bones in the foot?

Answer 42

accessory navicular os trigonum os peroneum

Question 43

what is the Apical Ectodermal Ridge?

Answer 43

it's an area of ectoderm at the end of each limb bud which promotes the differentiation and proliferation of mesenchymal cells into blood vessels, cartilage, muscle, bone

Question 44

by which week of embryological development do fingers and toes separate from eachother?

Answer 44

week 8 of development

Question 45

once hand and foot plates are formed in the embryo, what rotation occurs in each?

Answer 45

upper limb buds - rotate laterally | lower limb buds - rotate medially

Question 46

what's the structure responsible for limb development in the embryo?

Answer 46

apical ectodermal ridge

Question 47

during bone development in the embryo, what do the primary and secondary ossification centres form respectively?

Answer 47

primary ossification centre - diaphysis/shaft | secondary ossification centre - epiphysis

Question 48

what are the genes responsible for bone formation?

Answer 48

HOX genes

Question 49

what type of cells make up limb buds in the embryo?

Answer 49

ectoderm | mesenchyme

Question 50

what is syndactily?

Answer 50

fusion of fingers, either through webbing (cutaneous syndactily) or with fused bones (osseous syndactily)

Question 51

what causes syndactily?

Answer 51

digital rays don't develop in the hand plate in utero

Question 52

what is the commonest type of clubfoot seen in babies, and what does it look like?

Answer 52

talipes equinovarus - foot inverted medially and downwards

Question 53

how common is talipes equinovarus?

Answer 53

1 in 1000 babies