13.38 - Lower Limb DR Flashcards

1
Q

what are the major regions of the lower limb

A

gluteal region - buttock/hip (associated with trunk)

free lower limb - thigh, leg, foot

(leg = region between knee and ankle)

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2
Q

identify the homologous regions between the upper and lower limb

A

pectoral girdle = hip/buttock

arm = thigh

forearm = leg

elbow = knee

hand = foot

but the movements of the limbs are very different

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3
Q

compare the actions of homologous joints in the upper and lower limb

why is this

A

flexion at the elbow = anterior movement

flexion at the knee = posterior movement

the movements at the homologous joints are opposites

due to the permanent pronation/internal rotation (twisting) of the lower limb bud that occurs in utero between weeks 7-8

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4
Q

what are the consequences of the permanent pronation of the lower limb bud

A

flexors become posterior and extensors become anterior → actions at homologous joints have opposite orientations

anterior position → dermatomes of the LL have twisted and oblique fields, compare to UL which are much straighter

thumb is lateral whereas its homologous digit the large toe is medial

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5
Q

what are the bones associated with each region of the lower limb

A

pelvic girdle = buttock/hip

thigh = femur

patella = sesamoid bone of the knee which articulates anteriorly with distal end of femur

leg = tibia and fibula

foot = tarsals, metatarsals, phalanges

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6
Q

what is the hip/pelvic bone made up of

where do the pair meet

A

fusion of ilium, ischium and pubis

the 3 individual bones are not obvious in adults

pair of hip bones fuse with sacrum at sacroiliac joint and with each other at pubic symphysis

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7
Q

where do the ilium, ischium and pubis meet (before fusion)

A

triradiate cartilage separates the 3 bones

fusion of the cartilage begins at 15

the 3 bones (+ cartilage before fusion) form the acetabulum where the head of femur articulates

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8
Q

what forms the obturator foramen

A

fusion of the ischium in inferiorly and superiorly with the pubis:

ramus of ischium fuses with superior ramus of pubis

body of ischium fuses with inferior ramus of pubis

(ischium is more posterior)

(obturator foramen is covered with obturator membrane)

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9
Q

label diagram

A
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10
Q

label diagram

A
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11
Q

label the anterior view of the pelvis

A
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12
Q

label the diagram

what are the main features of the bone

what direction is the bone in the body

why is this important

A

proximal end - articulates with pelvis

distal end - articulates with tibial plateau

anterior surface of shaft is smooth

posterior surface of shaft has linea aspera → ridge which runs down the majority of the length (important for muscle attachment)

head and neck of femur is oblique, distal end is on a horizontal plane → makes thighs inferomedially oblique → makes knees close together and under pelvis → important for bipedal gait

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13
Q

label the ends of the femur

why are they so different

A

their structural features are based on the joints they create with other bones

proximal end:

head - ⅔ of a sphere

neck - relatively narrow → point of weakness but allows for greater mobility

distal:

articulates with proximal end of tibia

condyles are more rounded in the anterior to posterior axis → allows flexion and extension of knee

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14
Q

label the leg bones

what are the notable features of them

A

tibia is larger and is weight bearing
proximal end is widened to formal tibial plateau
distal end is slightly widened with inferior projection called medial malleolus
proximally - tibial plateau articulates with distal femur to form knee joint
distally - articulates with the talus tarsal bone to form ankle joint

fibula is lateral to tibia
more slender than tibia
not directly weight bearing → acts as a site muscle attachment
distally - lateral malleolus forms lateral wall of ankle joint
proximally - articulates laterally with proximal tibia to form proximal tibiofibular joint

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15
Q

how are the tibia and fibula connected

A

shafts are connected via fibrous interosseous membrane

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16
Q

describe the structure of the proximal ends of the leg bones

A

tibial plateau is divided into 3 parts → medial condyle, lateral condyle, intercondylar eminence which has pair of intercondylar tubercles

tibial tuberosity → (can be palpated just below knee) muscle attachment point

proximal tibiofibular joint - between proximal end of fibula and lateral proximal end of tibia

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17
Q

why is the fibular not weight bearing

A

because it does not articulate with the femur

proximally it articulates laterally with proximal end of tibia to form tibiofibular joint

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18
Q

label diagram of proximal end of leg bones

A
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19
Q

what are the surfaces of the foot

what are the movemenst of the foot

A

upper surface = dorsum

sole/lower surface = planta

plantarflexion → toes pointing inferiorly (when foot is on ground heel will be raised)

dorsiflexion - toes pointing superiorly

inversion - plantar surface of foot is turned medially

eversion - plantar surface of foot is turned laterally

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20
Q

describe the structure of the foot bones

A

posterior to anterior:
tarsals → metatarsals → phalanges

tarsals:

calcaneus = heel bone (most posterior)

talus (sits on top of calcaneus) articulates with medial and lateral malleolus of leg bones to form ankle joint

cuboid, navicular, 3 cuneiforms

metatarsals:

5 metatarsal, each with proximal base, shaft and distal head

phalanges:

each digit has 3 phalanges (proximal, middle, distal) , except hallux (big toe) which only has 2 (proximal and distal)

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21
Q

what bone is visible present only on the plantar surface of the foot

what is its function

A

sesamoid bones - pair of small bones seen in the 1st metatarsal phalangeal joint which are embedded in tendon of flexor hallucis brevis

bones important because they can bear most of the body’s weight when the heel is raised

they protect the important tendon - flexor hallucis longus which runs in between them

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22
Q

what can be observed on the medial and lateral views of the foot

A

arches of the foot

shape of the bones forms the arch

but maintenance of the arch needs muscle, tendons + ligaments

(note that the medial sesamoid bone is visible on the medial view of the foot)

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23
Q

what is function of the foot arches

A

distribute the bodyweight

stiffen the foot → whilst still allowing some flexibility and energy efficiency in walking and running

flat feet or high arches not only change footprint but also cause significant problems

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24
Q

describe the structure of the arches of the foot

A

3 arches

medial longitudinal arch, lateral longitudinal arch, transverse arch

medial - calcaneus, talus, navicular, 3 cuneiforms, 1st 2nd 3rd metatarsals
highest longitudinal arch

lateral - calcaneus , cuboid, 4th 5th metatarsal

transverse - metatarsal bass, cuboid, 3 cuneiforms
only visible in coronal plane

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25
Q

label the bones of the foot

A

calcaneus. talus, cuboid, navicular + 3 cuneiforms = tarsals

metatarsals have proximal head, shaft and distal base

digits 2-5 - proximal, middle, distal phalange

hollux - proximal and distal phalange

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26
Q

label the arches and the bones

A
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27
Q

label the arch and the bones

A
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28
Q

what connects the free lower limb and the trunk

A

hip joint - between head of femur and acetabulum

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29
Q

what are the joints of the lower limb

what types of joints are they

what bones are they between

A

sacro iliac joint - synovial joint (limited mobility)
between iliac bone and sacrum

pubic symphysis - fibrocartilaginous
between 2 bodies of pubis

hip joint - ball and socket synovial joint
between head of femur and acetabulum

patello-femoral joint - gliding synovial joint
between intercondylar fossa of femur and patella

proximal tibiofibular joint - plane synovial joint
between proximal head of fibula and lateral condyle of tibia

distal tibiofibular joint - fibrous joint
between fibular notch of distal tibia and distal fibula

ankle joint - synovial hinge
body of talus and distal ends of tibia and fibula

numerous joints within and between groups of bones in foot - mainly synovial
distal interphalangeal joints
proximal interphalangeal joints
metatarsophalangeal joints

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30
Q

label the joints

what type are they

what are the bones in between

A

sacro iliac joint - synovial joint (limited mobility)
between iliac bone and sacrum

pubic symphysis - fibrocartilaginous
between 2 bodies of pubis

hip joint - ball and socket synovial joint
between head of femur and acetabulum

patello-femoral joint - gliding synovial joint
between intercondylar fossa of femur and patella

proximal tibiofibular joint - plane synovial joint
between proximal head of fibula and lateral condyle of tibia

distal tibiofibular joint - fibrous joint
between fibular notch of distal tibia and distal fibula

ankle joint - synovial hinge
body of talus and distal ends of tibia and fibula

numerous joints within and between groups of bones in foot - mainly synovial
distal interphalangeal joints
proximal interphalangeal joints
metatarsophalangeal joints

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31
Q

what are the movements of the hip

what joint allows theses

A

flexion, extension

abduction, adduction

medial rotation, lateral rotation (more restricted movements)

hip joint → ball and socket synovial joint

highly mobile joint so needs stabilisation

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32
Q

describe the structure of the acetabulum

A

ilium, ischium and pubis all contribute to the acetabulum

incomplete inferiorly → gap called acetabular notch

in the acetabular notch there is the transverse acetabular ligament (completes the socket)

centrally there is a depression → acetabular fossa

in the acetabular fossa there is fibro-fatty tissue → makes the articular surface of the acetabulum a horseshoe shape → best shape for minimising contact stress in acetabulum

socket is deepened by rim of cartilage → acetabular labrum

ligament of the head of femur/ligamentum teres connects the acetabulum and the head of femur → ligament is connects the transverse acetabulum ligament and the fovea of the head of the femur

when head of fovea is in the acetabulum the ligament is pushed into acetabular fossa

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33
Q

label the structures

what is the significance of the acetabular structures

A

acetabular notch → completed by transverse acetabular ligament → attached to it is the ligamen of head of femur → attaches fovea of femur to acetabulum

what head of femur is in the socket the ligament of head of femur is in the acetabular fossa

acetabular fossa → contains fibro-fatty tissue → makes articular surface of acetabulum horseshoe shaped → bes shape for limiting contact stress

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34
Q

what ligaments stabilise the hip joint

A

3 capsular ligaments → thickened bands of hip joint capsule which connect hip bone and proximal femur

iliofemoral ligament - inserts anterior inferior iliac spine, broad distal attachment along inter-trochanteric line of proximal femur (y shaped)

pubofemoral - between superior pubic rami and inter-trochanteric line

ischiofemoral - between body of ischium and greater trochanter of femur (only visible posteriorly)

arrangement means when the ligaments are twisted they draw together the structures which they are attached to → distance between the structures is reduced
this happens in extension of hip joint → head of femur is drawn into joint → stabilising joint

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35
Q

label diagram

what is the ligament function

A

stabilise hip joint

especially during hip extension by drawing head of femur further into acetabulum

36
Q

what type of joint is the knee

what bones makes up the knee joint

A

synovial hinge joint

distal lateral and medial condyles of femur articulate with lateral and medial condyles of the tibial plateau

(patella and fibula do not directly contribute to the knee joint)

37
Q

what movements occur at the knee

A

flexion and extension

small degree of lateral and medial rotation of knee occurs during full extension → to lock and unlock the joint → but rotation is limited by ligaments

(opposite direction to the same movements at the hip)

38
Q

what is important to note about the structure of the knee

A

the distal femur and proximal tibia do not fit well together → the medial and lateral condyles on the proximal tibia only have very shallow depressions → not good fit for the femoral medial and lateral condyles

lack of stability → other structures are need to stabilise the joint → main ligaments are anterior and posterior cruciate ligaments, medial and lateral collateral ligaments

medial and lateral menisci are on the tibial condylar surfaces → the cartilage inccrease the congruence of the joint articulation by adapting to the change in femoral condylar shape as they roll over tibial plateau during flexion and extension

39
Q

what are the articular surfaces of the knee joint on the femur

A

distal lateral and medial condyles

between them anteriorly is patella

between them posteriorly is the intercondylar fossa

the condyles are a pair of surfaces that are convex in the anterior-posterior axis

40
Q

label the diagram

what bone is shown

A

distal femur and patella

41
Q

what is the tibial articular surface of the knee joint

A

medial and lateral condyles separated by intercondylar eminence which has pair of intercondylar tubercles

c shaped cartilage menisci on the condylar surfaces

42
Q

label the diagram

what bone is shown

A

proximal tibia

43
Q

what are the ligaments which stabilise the knee

what are their functions

anterior view

A

anterior and posterior cruciate ligaments → respectively attach to anterior and posterior of tibia → cross over each other → attach to intercondylar fossa of femur
limite anterior-posterior movements of femur relative to tibia

medial and lateral collateral ligaments → respectively connect the medial femur to tibia and lateral femur with head of fibula
prevent abduction and adduction at knee → limit knee to hinge activity

44
Q

label the diagram

what are the ligament functions

what movement is the knee doing

A

anterior and posterior cruciate ligaments = limit anterior-posterior movements of femur relative to tibia

medial and lateral collateral ligaments = prevent adduction and abduction of the knee

flexion of the right knee

45
Q

label this posterior view of the knee

A
46
Q

label this superior view

what is showing

what is important to note

A

superior view of tibial plateau

medial collateral ligament is attached to the medial meniscus → increased likelihood of damage to medial meniscus

47
Q

what are the purpose of bursae in the knee

A

synovial fluid filled sacs which acts as cushioning to allow tendons to slide over bony surfaces

some are isolated sacs → e.g. prepatellar bursae

some are outpouchings of the synovial capsule of the knee joint → e.g. suprapatellar bursa

48
Q

what is shown in this picture

what has likely caused it

A

bursitis → inflammation of the bursa

very painful

caused by repeated trauma from kneeling and weight bearing on hard surfaces

49
Q

what is the largest joint in the body

A

knee

50
Q

label the bursae

A
51
Q

what type of joint is the ankle

what movements can it do

A

synovial hinge joint

dorsiflexion = extension 
plantarflexion = flexion (when foot is on ground plantar flexion raises the heel → tiptoe)

inversion (plantar surface faces medially) and eversion (plantar surface faces laterally) do not occur at the ankle joint but at the subtarsal and other intertarsal joints

(joint between leg and foot)

52
Q

describe the structure of the ankle

A

involves tibia, fibula + talus

tibia and fibula for square shaped socket called a mortise

distal ends of tibia and fibula have prominences → medial malleolus and lateral malleolus respectively → which then form the medial and lateral walls of the socket

body of the talus then fits into the mortise (socket)

53
Q

what is the structure of the talus

why is this important

A

in the anterior to posterior axis the body of talus is domed

lateral and medial aspects are flatter and only articular with the lateral and medial malleolus

weight is transferred to the talus by only the tibia → the fibula is not weight-bearing, but is important as a site of muscle attachment and in forming the lateral wall of the ankle joint

54
Q

what is the structure of the talus

why is this important

A

in the anterior to posterior axis the body of talus is domed

lateral and medial aspects are flatter and only articular with the lateral and medial malleolus

weight is transferred to the talus by only the tibia → the fibula is not weight-bearing, but is important as a site of muscle attachment and in forming the lateral wall of the ankle joint

55
Q

what are the ligaments of the ankle

what are their functions

A

medial ligament - broad triangular ligament - fans out from the medial malleolus
prevents over-eversion of the ankle
anterior + posterior tibiotalar - between talus and medial malleolus
tibiocalcaneal - between calcaneus and medial malleolus
tibionavicular - between navicular and medial malleolus

lateral ligament - 3 distinct ligaments
prevents over inversion of the ankle
anterior and posterior talofibular - between talus and lateral malleolus
calcaneofibular - between lateral malleolus and calcaneus

56
Q

label the ligaments

A
57
Q

label the ligaments

A
58
Q

what is a sprained ankle

what is the most common pathology

A

when forced over inversion or over eversion causes damage to the medial or lateral ligaments of the ankle

medial ligament is very tough → is rarely damaged even by significant forced over-eversion

sprained ankles usually due to over-inversion → stretched or torn lateral ligaments

most commonly affected are the anterior talofibular and calcaneofibular ligaments

59
Q

what is most commonly damaged causing an ankle sprain

A

lateral ligaments:

anterior talofibular and calcaneofibular

60
Q

what are the movements shown here

what joints do they occur at

A

in the LL only at the hip joint is flexion anterior and extension posterior movement (in upper limb it is the same)

at the other joints e.g. ankle, knee flexion is posterior and extension is anterior

61
Q

what is circumduction

what joints can it occur at

A

composite movement → combination of adduction, abduction, flexion and extension

circular motion of joint

most commonly seen in shoulders and hip but any joint which can do all those 4 movements can circumduct

62
Q

how are muscles grouped

A

into compartments:

which have a distinct function and the same blood and nerve supply

each compartment is separated by connective tissue walls (septae)

63
Q

describe the fascia of the thigh

A

muscles of the thigh are covered by tough layer deep fascia → fascia lata

begins around the iliac crest and inguinal ligament and extends to bony prominences to tibial and femoral condyles + patella + head of fibula

(acts like cycling shorts)

laterally a band of the fascia lata is thickened → forms iliotibial tract (acts like a tendon)

64
Q

what are the muscles of the gluteal region

A

superficial muscles - extensors and abductors of the hip
gluteus maximus
gluteus medius
gluteus minimus
tensor fascia latae

shorter deep muscles - lateral rotators of the hip
piriformis
obturator internus
superior and inferior gemelli
quadratus femoris

65
Q

what are the origins and attachment of the hip extensors + abductors

A

gluteus maximus - largest and most superior muscle
origin - posterior iliac crest and sacrum
insertion - ¼ pf the fibres travel inferiorly and attach to gluteal tuberosity of femur, ¾ of fibres insert into iliotibial tract
major hip extensor

gluteus medius
origin - broad fan- shaped attachment to posterior ilium
insertion - greater trochanter of femur

gluteus minimus
origin posterior surface of ilium
insertion - greater trochanter of femur
when lower limb is planted on ground → stabilises tilt of pelvis

tensor fascia lata (most anterior gluteal muscle, is superior to gluteus minimus + part of gluteus maximus)
originates from outer lip of anterior iliac crest
insertion - iliotibial tract (itself attches to lateral tibial condyle)
tightens the fascia lata → stabilises hip during extension

66
Q

label the muscles of the gluteal region

A
67
Q

what are the anterior thigh muscles

what are their functions

A

mainly hip flexion and knee extension

quadriceps:
4 heads (superficial to deep) - rectus femoralis, vastus medialis, vastus lateralis, vastus intermedius
origin - vasti originate from femur
knee extensor
origin of rectus femoralis - Anterior inferior iliac spine
knee extensor and hip flexor (as it crosses the hip joint)
all unite to form quadriceps tendon which attaches to patella

iliopsoas:
origin- iliacus is iliac fossa, psoas major is lumbar vertebrae
attachment - lesser trochanter of femur
they merge as they pass under inguinal ligament → attach to lesser trochanter of femur
psoas major and iliacus merge to form iliopsoas → major hip flexor

pectineus:
origin - superior pubic ramus
attachment - posterior of shaft of femur
flexion and adduction of hip

sartorius (most superficial muscle of anterior thigh):
longest muscle in body, runs in inferomedial direction
origin - ASIS
attachment - medial surface of tibia
flexor of hip and knee, abduction and lateral rotation of hip

68
Q

what is the patellar ligament

A

attachment of the patella inferiorly to the tibial tuberosity

69
Q

label the diagram

mainly what muscle compartment is shown

A

anterior compartment of thigh

70
Q

what are the muscles of the medial compartment

A

mainly hip adductors
important for maintaining stance and gait
can contribute to hip flexion and extension (depending on thigh position)

mostly triangular muscles originating from ischium or pubis which pass obliquely to form broader distal attachments at posterior of shaft of femur (except gracilis → strap muscle which attaches to tibia)

adductor longus:
originates - body of pubis
insertion - linea aspera of femur
adduction of hip

adductor brevis:
originates - body of pubis and inferior pubic rami
insertion - linea aspera of femur
adduction of hip

adductor magnus (largest in compartment, most posterior):
origin - external border of ischiopubic ramus
insertion - upper part inserts on linea aspera, lower part inserts on adductor tubercle of femur, gap between them is adductor hiatus
adduction of hip

gracilis (most medial):
insertion - inferior pubic ramus
insertion - medial surface of tibia
adduction of hip

obturator externus:
origin - obturator membrane + ischiopubic rami
insertion - trochanteric fossa (on posterior aspect of femur)
adduction of hip + lateral rotation

71
Q

what is groin strain

A

overstretch of muscles the hip adductor muscles in the thigh

anterior compartment of thigh - pectineus

medial compartment of thigh - adductor longus, adductor brevis, gracilis, obturator externus

72
Q

label the muscles

what compartment is shown

what is their main function

A

medial thigh muscles

hip adduction

73
Q

what are the muscles of the posterior compartment of thigh

what is their function

A

3 hamstrings → elongated + spindle shaped muscles

leg flexion and hip extension

all originate from ischial tuberosity except short head of biceps femoris

semitendinosus:
insertion - medial surface of tibia
covers majority of semimembranosus, both travel down medial side of femur + knee joint

semimembranosus:
insertion - medial tibial condyle

biceps femoris (most lateral):
2 heads - long and short 
short head origin - linea aspera of posterior femur 
merge in distal thigh → form singe tendon → cross knee → inserts into head of fibula

NOTE: hamstring portion of adductor magnus has the same function and innervation as these main hamstring muscles

74
Q

label the muscles

what compartment are they

what is their function

A

posterior thigh

leg flexion and hip extension

75
Q

what are the muscle compartments of the leg

A

anterior (shin) - extensors (dorsiflexion)

lateral (smallest) - foot eversion

posterior (largest) - flexors (plantarflexion)

anterior and posterior compartments are separated by the tibia and fibula + their interosseous membrane

lateral compartment is separated from the other compartments by connective tissue walls

76
Q

how are the muscles of the leg and foot classified

A
77
Q

what are the muscles of the anterior compartment of the leg

what are their functions

A

supplied by deep peroneal nerve and anterior tibial artery

dorsiflexors → extensors of foot and toes)

tibialis anterior (most superficial)
origin - lateral surface of tibia
insertion - medial cuneiform + base of 1st metatarsal
dorsiflexes and inverts foot

extensor digitorum longus:
origin - medial fibula, lateral tibial condyle + interosseous membrane
insertion - distal + middle phalanges of toes 2-5
extension of 4 lateral toes + dorsiflexes foot

extensor hallucis longus:
origin - medial surface of fibula
insertion - base of distal phalanx of great toe
extension of hallux and dorsiflexes foot

peroneus tertius:
origin - from most inferior part of extensor digitorum longus
insertion - base of 5th metatarsal
weakly assists dorsiflexion + eversion

78
Q

what causes shin splints

A

damage to muscles in anterior compartment of leg → particularly to tibialis anterior

79
Q

label the muscles

what compartment are they

what is their function

A

anterior compartment

dorsiflexors → extensors of foot + toes

80
Q

what are the muscles of the lateral compartment of the leg

what are their function

A

2 muscles - peroneus brevis and peroneus longus
both originate from fibula → form tendons → tendons enter the foot by passing posteriorly to the lateral malleolus → then travels under the foot

carry out foot eversion

peroneus longus (larger and more superficial):
origin - lateral fibula + lateral tibial condyle
insertion - at the area between cuboid and 5th metatarsal joint the tendon crosses from lateral to medial and then inserts at the 1st metatarsal joint
foot eversion and plantar flexion

peroneus brevis:
origin - lateral surface of fibular shaft
insertion - at the tubercle of the 5th metatarsal joint
foot eversion

Note: peroneus tertius is in the anterior compartment and weakly involved in dorsiflexion + eversion

81
Q

label the muscles

what compartment is shown

what is the function

A

lateral leg muscles

foot eversion

82
Q

what are the muscles of the posterior compartment of the leg

what are their functions

A

superficial and deep group
deep group are posterior versions of the anterior muscles of the leg

involved in plantar flexion (true flexion)

superficial group:

gastrocnemius (most superficial)
2 heads - medial + lateral
origin - medial and lateral femoral condyles respectively
heads converge to form single muscle belly
insertion - converge with soleus to form triceps surae and the calcaneal tendon (achilles) inserts into calcaneus
plantar flexion

soleus:
origin - soleal line of tibia and proximal fibula
insertion - joins calcaneal tendon inserts into calcaneus
plantar flexion

plantaris:
small muscle with a very long tendon
origin - lateral femoral condyle
insertion - joins calcaneal tendon very close to calcaneus
weakly assists with plantarflexion

Deep:

popliteus (most superior):
runs in inferomedial direction - narrow origin, broad distal attachment
origin - lateral condyle of femur
insertion - posterior surface of proximal tibia, just above soleal line
lateral rotates femur (relative to tibial plateau) to unlock knee joint when fully extended

tendons pass to plantar surface of foot via medial malleolus

flexor digitorum longus (medially located):
origin - medial surface of tibia
insertion - bases of distal phalanges 2-5
flexion of toes 2-5

flexor hallucis longus (laterally located):
larger than FDL
travels medially
origin - posterior surface of fibula
insertion - base of distal phalanx of hallux
flexion of hallux

tibialis posterior (deepest):
between FDL and FHL
origin - posterior interosseous membrane + the posterior areas of tibia and fibula adjacent
insertion - medial plantar tarsal region (navicular, cuboid, cuneiform)
foot inversion + weakly assists with plantar flexion

83
Q

what is the clinical significance of plantaris

A

posterior compartment of leg (superficial)

weakly assists with plantar flexion

very long tendon which can be harvested for reconstruction

84
Q

what makes up the achilles tendon

A

calcaneal tendon

tendon of triceps surae muscle - gastrocnemius + soleus merge

distal tendon attaches to calcaneus

85
Q

label the muscles

what compartment is shown

what is their function

A

superficial muscles of the posterior compartment

plantar flexion

86
Q

label the muscles

what is their function

A

posterior muscles of the leg (deep)

popliteus - lateral knee rotation

plantar flexion, toe flexion, foot inversion

87
Q

what are the muscles of the foot

A

intrinsic muscles of foot

dorsum of foot:

extensor digitorum brevis:
helps extensor digitorum longus with extension of toes 2-5

extensor hallucis brevis:
helps extensor hallucis longus with extension of hallux

plantar surface of foot:

10 intrinsic muscles

4 layers

1st layer - immediately inferior to fascia
abductor hallucis, abductor digiti minimi, flexor digitorum brevis

in between 1st and 2nd layer is flexor hallucis longus and flexor digitorum longus tendons

2nd layer:
quadratus plantae
lumbricals