Knee/Leg/Ankle Flashcards
knee joint type
hinge type synovial
knee joint stability
dependent on surrounding muscles/ligaments
-quadriceps femoris
knee joint articulations
tibia and femur
patella and femur
knee joint movements
flexion/extension
MR/LR (slight)
openings in knee joint capsule
posterior to allow for tendon of popliteus muscle
collateral ll.
fibular colateral l.
tibial colateral l.
fibular colateral l.
strong and cord like
taut with extension
lateral mensicus separated by t of popliteus muscle
tibial colateral l.
strong and flat
taut with extension
attaches to medial meniscus via deep fibers
more prone to injury
cruciate ll. rotation
limit MR to about 10 degrees
LR to nearly 60 degrees
anterior cruciate l.
weaker - poor blood supply
displacement and hyperextension:
-prevents posterior displacement of femur on tibia
-prevents anterior displacement of tibia on femur (flexed knee)
-resists hyper extension
posterior cruciate l.
-prevents anterior displacement of femur on tibia
prevents posterior displacement of tibia on femur
resists hyperflexion of knee
menisci
plates of fibrocartilage
menisci functions
shock absorbers
deepen tibial plateu
medial meniscus
C shaped
adheres to TCL
less mobile = more prone to injury
lateral meniscus
nearly circular
smaller and more moveable
causes of ACL rupture
hyperextension of knee
lateral blow at knee with weight on that limb
location of ACL rupture
most commonly in mid point of ligament
when knee flexed tibia slights anterior on fixed femur
-anterior drawer sign
PCL tear
not common
usually occur in conjunction with FCL and TCL injuries
causes of PCL tear
car accident
knee hits dashboard
mechanism of PCL tear
tibia slide posteriorly under fixed femur
posterior drawer sign
politeal fossa contents
adipose tissue
popliteal a. and v. (a. is deepest)
terminal part of small saphenous v. (drains to popliteal)
common fibular and tibial nerve (superficial)
popliteal artery
continuation of femoral a. after adductor hiatus
one of four places to take pulse
terminates by dividing into anterior and posterior tibial aa. at inferior border of popliteus
inferior tibiofibular joint type
compound fibrous joint (syndesmosis)
inferior tibiofibular joint talocrural stabilty
holds lateral maleolus against talus
inferior tibiofibular joint formed by
interosseus membrane (interosseus tibiofubular l.)
anterior inferior tibiofibular l.
posterior inferior tibiofibular l.
inferior tibiofibular joint movement
permits slight movement to accomodate wide portion of trochlea during dosriflexion
deep fascia (crural fascia)
attaches to anterior and medial borders of tibia
blends with preiosteum where it passes over bone
deep fascia 3 compartments
anterior
lateral
posterior
deep fascia transverse intermuscular septum
divides posterior compartment into superficial and deep
deep fascia retinacula
thickened bands of crural fascia
binds tendons proximal and distal to ankle joint
prevents bowstringing
different retinacula
superior/inferior extensor
superior/inferior fibular
flexor (cont of transverse intermuscular septum)
anterior compartment of leg
tibialis anterior
extensor hallucis longus
extensor digitorum longus
fibularis tertius
anterior compartment of leg common innervation
deep fibular n.
anterior compartment of leg common function
dorsiflexion
tibialis anterior
most medial and superficial dorsiflexor
lies against lateral surface of tibia
strongest dorsiflexor
tibialis anterior actions
dorsiflexion of foot
inversion of foot
tibialis anterior innervation
deep fibular n.
extensor hallucis longus
lies deep between tibialis anterior and extensor digitorum longus at its superior attachment
rises to surface in distal 1/3 of leg
found between extensor hallicus longus and tibialis anterior
deep fibular n.
anterior tibial a.
what does anterior tibial a become when it passes below extensor retinaculum
dorsalis pedis a.
1/4 places to take pulse in lower limb
extensor hallucis longus actions
extension of great toe
dorsiflexion of foot
extensor hallucis longus innervation
deep fibular nerve
extensor digitorum longus
most lateral of anterior compartment muscles
forms 4 tendons that attach to phalanges
extensor digitorum longus actions
extension of lateral 4 digits
dorsiflexion of foot
separated part of extensor digitorum longus
fibularis teritius
fibularis teritius
separated part of extensor digitorum longus
not always present
look for 5th tendon going to dorsum of 5th metatarsal
actions: dorsiflexion and aids in eversion of foot
extenosor digitorum longus
deep fibular n.
compartment syndromes
facial compartments are closed spaces
end proximally and distally at joints
causes of compartment syndromes
hemmorage and edema
inflammation of muscles
-increases intra-compartmental pressure
compartment syndromes results of high pressure
compresses arteries
threatens function and viability of tissues
compartment syndromes signs
structures distal to compressed areas can become ischemic
loss of pulse distally is a sign of arterial compression
temp may also be decreased
tibialis anterior sprain (chin splints)
mild form of anterior compartment syndrome
called exertional compartment syndrome
tibialis anterior sprain (chin splints) mechanism of injury
repetitive microtrauma
overexertion by untrained person
tibialis anterior sprain (chin splints) results
small tears in periosteum of tibia and/or fleshy attachements to deep fascia
tibialis anterior sprain (chin splints) symptoms
edema and pain in distal 2/3 of tibia
enough swelling can decrease blood flow to area
which anterior compartment muscles cross the ankle
all of them (have to to dorsiflex)
lateral compartment of leg muscles
fibularis longus - helps steady foot when standing
fibularis brevis - lies deep to fibularis longus
lateral compartment of leg muscles common function
eversion of foot
weak plantar flexion of foot
lateral compartment of leg muscles common innervation
superficial fibular n.
lateral compartment of leg muscles called in clinics
peroneus
fracture of 5th metatarsal causes
sudden violent inversion of ankle
common in tenis/basketball
fracture of 5th metatarsal and fibularis brevis m
can fracture or avulse 5th metatarsal
fracture of 5th metatarsal symptoms
pain and edema around 5ht metatarsal
fracture of 5th metatarsal misdiagnosis
often diagnosed as ankle inversion sprain
posterior compartment of leg compartments
superficial (3 muscles) and deep (4 muscles)
posterior compartment of leg muscles common innervation
tibial n.
posterior compartment of leg muscles common function
plantarflexion
gastrocnemius m
most superficial of posterior leg
gastrocnemius heads
medial and lateral
gastrocnemius joints crossed
knee and ankle
gastrocnemius m. function most effictevely when
knee is extended
if knee is fully flexed will not plantar felx
gastrocnemius actions
plantarflexion with knee extended
flexion of leg
gastrocnemius innervation
tibial n.
soleus m.
deep to gastrocnemius
“workhorse” of plantarflexion
soleus actions
plantarflexion independent of knee postion
accessory soleus
present 3% of time
medial to calcneal t.
soleus innervation
tibial n. q
plantaris m.
absent 5-10% of time
small fat muscle belly, long skinny tendon
plantaris m. actions
weak plantarflexion
may function in proprioception (high density of mm spindles)
plantaris m. innervation
tibial n.
“student’s/freshman nerve”
plantaris m. (looks like nerve)
popliteus m
tendon emerges form posterior aspect of knee joint capsule
popliteal fossa
forms inferior part of floor
popliteus m actions
weak flexion of leg
unlocks knee by rotating femur 5 degrees on fixed tibia
medially rotates tibia of unplanted limb
popliteus m inervation
tibial n.
tibialis posterior
“Tom”
deepest muscles of deep posterior compartment
between flexor digitorum and flexor halluicis (cross under flexor digitorum longus)
tendon passes immediately posterior to medial maleols
tibialis posterior important for
supporting medial longitiuduinal arch of foot
supports talar head
tibialis posterior actions
plantarflexion of foot
inversion of foot
tibialis posterior innervation
tibial n.
flexor digitorum longus
on medial aspect of leg
tendon crosses tibialis posterior m . superior to medial malleolus
tendon then passes posterior to medial malleolus
tendon then crosses flexor halluicis longus t. in foot
flexor digitorum longus actions
“DICK”
flexion of digits 2-5
plantar flexion of foot
flexor digitorum longus innervation
tibial n.
flexor hallucis longus
“Harry”
powerful flexor of great toe
most lateral muscle of deep post compartment
tendon passes posterior to medial malleolus and inferior to sustentaculum tali (bone on calcaneous)
flexor hallucis longus actions
flexion of great toe
plantar flexion of foot
flexor hallucis longus innervation
tibial n.
tom dick and harry
relationships of tendons and neruovascular strucutures to medial malleolus
ONLY applies as they pass posterior to medial maleolus, deep to flexor retinaculum
which t is found inferior to sustentaculum tali
flexor hallucis longus
anterior tibial a. origin
popliteal artery
anterior tibial a.
passes ant. through proximal gap in IOM
anterior tibial a. runs with
deep fibular n.
anterior tibial a. changes name
at ankle joint
anterior tibial a. termination
dorsalis pedis a.
one of 4 places to take pulse in lower limb
posterior tibial a. origin
popliteal artery
posterior tibial a.
runs deep in posterior compartment with tibial n.
A in TDANH
deep to flexor retinaculum and posterior to medial maleolus between dick and posterior tibial v.
posterior tibial a.
one of 4 places to take pulse in lower limb
posterior tibial a. termination
medial and lateral plantar aa.
small saphenous v. origin
lateral aspect of dorsal venous arch
small saphenous v. runs with
sural n.
small saphenous v. path
ascends posterior to lateral maleolus
ascends between heads of gastrocnemius
small saphenous v. termination
drains into popliteal v.
varicose veins
more common in women than men
can affect small or great saphenous vv. or any tributaries
normal valves vs incompetent valves
normal- allow blood to flow toward heart while keeping from flowing away
incompetent - blood flows inferiorly and vein becomes dilated (varicose), become thick and rope like
varicose veins symptoms
pain
swelling
restless leg
burning, itching skin
phlebitis
skin ulcers
deep vein thrombosis venous stagnation due to
major surgery (material released during)
incompetent fascia
external pressure on veins
muscular inactivity
other contributing factors to DVT
age and previous history
varicose vv.
smoking and obesity
estrogen usage or pregnancy
classic signs of DVT
calf discomfort
edema
foot pain
warmth and inflammation
DVT may partially or fully block blood flow causing
pooling at distal site
chronic swelling and pain
pulmonary embolism
large thrombus broken free and traveled to lung
can cause pulmonary artery and death
can kill within hours
post hip surgery dvt
thrombi often form in thigh
more likely to lead to PE
post knee surgery dvt
most thrombi occur in calf
common fibular nerve
branch of sciatic nerve
wraps around fibular neck (very superficial)
supplies skin of upper lateral leg
common fibular nerve gives rise to
sural comminucating branch
joins with medial sural cutaneous n. to form sural n.
common fibular nerve termination
deep and superficial fibular nn.
deep fibular nerve compartment
anterior
deep fibular nerve origin
common fibular n.
deep fibular nerve runs with
anterior tibial a.
deep fibular nerve sensory zone
flip flop zone
deep fibular nerve termination
lateral branch of deep fibular (motor)
medial branch of deep fibular (sensory)
superficial fibular n. compartment
lateral compartment
superficial fibular n. origin
common fibular n.
superficial fibular n. sensory to
inferolateral leg and dorsum of foot
superficial fibular n. termination
intermediate dorsal cutaneous n,.
medial dorsal cutaneous n.
tibial n.
branch of sciatic n.
tibial n. innervation
all muscles in posterior compartment of leg
tibial n. path
passes posterior to medial maleolus between flexor digitorum longus and flexor hallucis longus tt.
tibial n. termination
medial plantar n.
lateral plantar n.
injury to common fibular n.
most commonly injured nerve in lower limb due to superficial location
injury to common fibular n. mechanism of injury
fracture of fibular neck or stretched with knee dislocation; kick boxing
injury to common fibular n. muscles affected
all those in anterior and lateral compartments of leg
injury to common fibular n. sign
foot drop - plantar flexors are unopposed
unopposed inversion makes limb too long, toes wont clear ground
injury to common fibular n. sensory loss
anterolateral leg and majority of dorsum of foot
injury to tibial n. in popliteal fossa
superficial here
rarely injured in leg as it lies deep to gastrocnemius and soleus m.
injury to tibial n. in popliteal fossa affected mm.
posterior compartment of leg
intrinsic mm of foot
unable to plantarflex foot or flex toes
injury to tibial n. in popliteal fossa n. sensory loss
plantar surface of foot
injury to tibial n. at ankle mechanism of injury
trauma to or around medial maleolus
compression/crushing
injury to tibial n. at ankle affected mm
intrinsic mm of foot
injury to tibial n. at ankle sensory loss
plantar surface of foot
ankle (talocrural) joint
hinge-type synovial
ankle (talocrural) joint articulations
talus with tibia superiorly and medially
talus with fibia laterally
ankle (talocrural) joint movements
dorsi and plantar flexion
ankle (talocrural) joint joint capsule
weak anteriorly and posteriorly
strengthened medially and laterally by collateral ligaments
ankle (talocrural) joint stable position
dorsiflexion - wedges wide, portion of talus between two malleoli
ankle (talocrural) joint unstable position
plantar flexion - narrow, anterior part of talus is between two malleoli, allows for wobble
lateral collateral l of ankle function
reinforces joint laterally
lateral collateral l of ankle resists
inversion
lateral collateral l of ankle composed of 3 ligaments
anterior talofibular - weak, commonly torn
calcaneofibular - cord like
posterior talofibular - thick and strong
medial collateral l of ankle function
reinforces medially
medial collateral l of ankle resists
eversion
medial collateral l of ankle composed of 4 ligaments
tibionavicular l
anterior tibiotalar
posterior tibiotalar
tibiocalcaneal
(form deltoid l. together)
ankle sprain common type
inversion
injures lateral ligaments
ankle sprain most commonly torn
anterior talofibular
sever may injure calcaneofibular l
ankle sprain may fracture
lateral malleolus
ankle sprain less common
eversion sprains less common, but often more serious
eversion ankle sprain ligaments injured
deltoid l
everison ankle sprain medial malleolus
may avulse of fracture as deltoid l very strong
