13.38 - Lower Limb DR Flashcards
what are the major regions of the lower limb
gluteal region - buttock/hip (associated with trunk)
free lower limb - thigh, leg, foot
(leg = region between knee and ankle)
identify the homologous regions between the upper and lower limb
pectoral girdle = hip/buttock
arm = thigh
forearm = leg
elbow = knee
hand = foot
but the movements of the limbs are very different
compare the actions of homologous joints in the upper and lower limb
why is this
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
what are the consequences of the permanent pronation of the lower limb bud
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
what are the bones associated with each region of the lower limb
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
what is the hip/pelvic bone made up of
where do the pair meet
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
where do the ilium, ischium and pubis meet (before fusion)
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
what forms the obturator foramen
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)
label diagram
label diagram
label the anterior view of the pelvis
label the diagram
what are the main features of the bone
what direction is the bone in the body
why is this important
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
label the ends of the femur
why are they so different
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
label the leg bones
what are the notable features of them
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
how are the tibia and fibula connected
shafts are connected via fibrous interosseous membrane
describe the structure of the proximal ends of the leg bones
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
why is the fibular not weight bearing
because it does not articulate with the femur
proximally it articulates laterally with proximal end of tibia to form tibiofibular joint
label diagram of proximal end of leg bones
what are the surfaces of the foot
what are the movemenst of the foot
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
describe the structure of the foot bones
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)
what bone is visible present only on the plantar surface of the foot
what is its function
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
what can be observed on the medial and lateral views of the foot
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)
what is function of the foot arches
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
describe the structure of the arches of the foot
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
label the bones of the foot
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
label the arches and the bones
label the arch and the bones
what connects the free lower limb and the trunk
hip joint - between head of femur and acetabulum
what are the joints of the lower limb
what types of joints are they
what bones are they between
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
label the joints
what type are they
what are the bones in between
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
what are the movements of the hip
what joint allows theses
flexion, extension
abduction, adduction
medial rotation, lateral rotation (more restricted movements)
hip joint → ball and socket synovial joint
highly mobile joint so needs stabilisation
describe the structure of the acetabulum
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
label the structures
what is the significance of the acetabular structures
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
what ligaments stabilise the hip joint
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
label diagram
what is the ligament function
stabilise hip joint
especially during hip extension by drawing head of femur further into acetabulum
what type of joint is the knee
what bones makes up the knee joint
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)
what movements occur at the knee
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)
what is important to note about the structure of the knee
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
what are the articular surfaces of the knee joint on the femur
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
label the diagram
what bone is shown
distal femur and patella
what is the tibial articular surface of the knee joint
medial and lateral condyles separated by intercondylar eminence which has pair of intercondylar tubercles
c shaped cartilage menisci on the condylar surfaces
label the diagram
what bone is shown
proximal tibia
what are the ligaments which stabilise the knee
what are their functions
anterior view
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
label the diagram
what are the ligament functions
what movement is the knee doing
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
label this posterior view of the knee
label this superior view
what is showing
what is important to note
superior view of tibial plateau
medial collateral ligament is attached to the medial meniscus → increased likelihood of damage to medial meniscus
what are the purpose of bursae in the knee
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
what is shown in this picture
what has likely caused it
bursitis → inflammation of the bursa
very painful
caused by repeated trauma from kneeling and weight bearing on hard surfaces
what is the largest joint in the body
knee
label the bursae
what type of joint is the ankle
what movements can it do
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)
describe the structure of the ankle
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)
what is the structure of the talus
why is this important
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
what is the structure of the talus
why is this important
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
what are the ligaments of the ankle
what are their functions
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
label the ligaments
label the ligaments
what is a sprained ankle
what is the most common pathology
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
what is most commonly damaged causing an ankle sprain
lateral ligaments:
anterior talofibular and calcaneofibular
what are the movements shown here
what joints do they occur at
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
what is circumduction
what joints can it occur at
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
how are muscles grouped
into compartments:
which have a distinct function and the same blood and nerve supply
each compartment is separated by connective tissue walls (septae)
describe the fascia of the thigh
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)
what are the muscles of the gluteal region
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
what are the origins and attachment of the hip extensors + abductors
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
label the muscles of the gluteal region
what are the anterior thigh muscles
what are their functions
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
what is the patellar ligament
attachment of the patella inferiorly to the tibial tuberosity
label the diagram
mainly what muscle compartment is shown
anterior compartment of thigh
what are the muscles of the medial compartment
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
what is groin strain
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
label the muscles
what compartment is shown
what is their main function
medial thigh muscles
hip adduction
what are the muscles of the posterior compartment of thigh
what is their function
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
label the muscles
what compartment are they
what is their function
posterior thigh
leg flexion and hip extension
what are the muscle compartments of the leg
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
how are the muscles of the leg and foot classified
what are the muscles of the anterior compartment of the leg
what are their functions
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
what causes shin splints
damage to muscles in anterior compartment of leg → particularly to tibialis anterior
label the muscles
what compartment are they
what is their function
anterior compartment
dorsiflexors → extensors of foot + toes
what are the muscles of the lateral compartment of the leg
what are their function
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
label the muscles
what compartment is shown
what is the function
lateral leg muscles
foot eversion
what are the muscles of the posterior compartment of the leg
what are their functions
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
what is the clinical significance of plantaris
posterior compartment of leg (superficial)
weakly assists with plantar flexion
very long tendon which can be harvested for reconstruction
what makes up the achilles tendon
calcaneal tendon
tendon of triceps surae muscle - gastrocnemius + soleus merge
distal tendon attaches to calcaneus
label the muscles
what compartment is shown
what is their function
superficial muscles of the posterior compartment
plantar flexion
label the muscles
what is their function
posterior muscles of the leg (deep)
popliteus - lateral knee rotation
plantar flexion, toe flexion, foot inversion
what are the muscles of the foot
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
