Leg Flashcards
What is the leg defined as
Lower limb between knee and ankle
What are the bones of the leg and where are they located?
Tibia: Medial
Fibula: Lateral
What is unique about the Tibia
It is subcutaneous along its entire length
What is found at the proximal end of the Tibia and what does it articulate with?
Lateral and Medial Condyle
Articulate with femur
What is found at the Distal end of the Tibia and what does it articulate with?
Medial Malleolus
projects medially and inferiorly
Articulates with Talus bone of foot
Which bones of the leg participate in formation of the knee joint
Just Tibia
Which bones of the legs are weight barring
Just Tibia
What is found at the proximal end of the Fibula and what does it articulate with?
Fibular head
articulates with lateral condyle of the tibia
What is found at the distal end of the Fibula and what does it articulate with?
Lateral malleolus
Articualtes with the Talus bone of the foot
What unites the Tibia and fibula
Strong fibrous sheet called:
Interosseous Membrane
What is the deep fascia of the leg called and where does it attach
Crural fascia
Superiorly attached to bony structures of the knee but continuous posteriorly with Fascia latae
What are the compartments of the leg and what seperates them
Septa of cural fascia divides:
- Anterior
- Lateral
- Posterior
Transverse Intermuscular septum divides Posterior:
Posterior divided into:
superficial and deep
What happens with the crural fascia at the ankle
Thickened by transverse fibers that form retinacula
over the tendons
What is the role of the retinacula in the ankle
prevent bowstringing of tendons during muscular contraction
What is the path of the tendons of the anterior leg muscles pass as they enter the foot?
Pass deep to the:
Superior extensor retinacula
Inferior extensor retinacula
What is the path of the tendons of the lateral leg muscles pass as they enter the foot?
Pass deep to the:
Superior fibular retinacula
Inferior retinacula
And Posterior to:
Lateral malleolus
What is the path of the tendons of the deep posterior leg muscles pass as they enter the foot?
Deep to:
Flexor retinaculum
And Posterior to:
medial Malleolus
What accompanies the tendons of the deep posterior leg muscles pass as they enter the foot?
Posterior tibial artery
Posterior tibial vein
Tibial nerve
(travel same path)
What are the muscles of the anterior leg from medial to Lateral? (4)
Tibialis anterior
Extensor Hallucis longus
Extensor digitorum longus
Fibularis tertius
What is the origin and insertion of the Tibialis anterior muscle?
Origin:
-Lateral surface of the tibia and overlying crural fascia
Insertion:
- medial cuniform bone
- 1st Metatarsal
What is the action of the Tibialis anterior muscle?
Dorsiflexes Foot
Inverts Foot
What is the innervation of the Tibialis anterior muscle?
Deep Fibular Nerve
L4, L5, S1, S2
What is the origin and insertion of the Extensor Hallucis Longus muscle?
Origin:
Middle part of fibula and interosseous membrane
Insertion:
Distal phalanx of big toe (hallux)
What is the action of the Extensor Hallucis Longus muscle?
Primarily Extends Big toe and dorsiflexes foot
Also weakly inverts foot
What is the innervation of the Extensor Hallucis Longus muscle?
Deep Fibular Nerve
L4, L5, S1, S2
What is the origin and insertion of the Extensor digitorum Longus muscle?
Origin:
proximal part of the fibula and interosseous membrane
Insertion:
Middle and distal Phalanges of the lateral 4 digits
(form extensor expansions on toes)
What is the action of the Extensor digitorum Longus muscle?
Extends toes and dorsiflexes foot
also weakly inverts foot
What is the innervation of the Extensor digitorum Longus muscle?
Deep Fibular Nerve
L4, L5, S1, S2
What is the origin and insertion of the Fibularis Tertius muscle?
Is a part of extensor Digitorum Longus
Origin:
Distal part of the finula and interosseous membrae
Insertion:
Base of the 5th metatarsal
What is the action of the Fibularis Tertius muscle?
Dorsiflexes the foot
aids in eversion
What is the innervation of the Fibularis Tertius muscle?
Deep Fibular Nerve
L4, L5, S1, S2
What are the muscles of the lateral leg? (2)
Fibularis longus
Fibularis brevis
What is the origin and insertion of the Fibularis longus muscle?
Origin:
Proximal 2/3rds of fibula
Crosses sole of foot then inserts:
Medial Cuniform
1st metatarsal bones
What is the action of the Fibularis longus muscle?
- Eversion of the foot
- assist in plantar flexion
What is the innervation of the Fibularis longus muscle?
Superfical Fibular nerve
L4, L5, S1, S2
What is the origin and insertion of the Fibularis Brevis muscle?
Origin:
Distal 2/3rds of fibula
Insertion:
tuberosity of the 5th metatarsal
What is the action of the Fibularis Brevis muscle?
- Eversion of the foot
- assist in plantar flexion
What is the innervation of the Fibularis Brevis muscle?
Superfical Fibular nerve
L4, L5, S1, S2
What are the muscles of the Posterior Leg? (Superficial/Deep) (7)
Superficial:
- Gastrocnemius
- Soleus
- Plantaris
Deep
- Politeus
- Flexor Digitorum Longus
- Tibialis Posterior
- Flexor Hallucis longus
What is the origin and insertion of the Gastrocnemius muscle?
Most superficial of posterior
Origin:
2 heads from lateral and medial condyles of femur
Insertion:
posterior surface of calcaneous bone through common tendon: calcaneal/achilles tendon
What is the action of the Gastrocnemius muscle?
Active in plantar flexion of the foot
Flexes knee when not weight bearing
What is the innervation of the Gastrocnemius muscle?
Tibial nerve
L4,L5, S1-3
What is the origin and insertion of the Soleus muscle?
Origin:
horse shoe shaped origin from tibia and fibula (as such does not act on knee joint)
Insertion:
posterior surface of calcaneous bone through common tendon: calcaneal/achilles tendon
What is the action of the Soleus muscle?
Active in plantar flexion of the foot
What is the innervation of the Soleus muscle?
Tibial nerve
L4,L5, S1-3
What is the origin and insertion of the Plantaris muscle?
Origin:
- Lateral Supracondylar line of femur
- Oblique popliteal ligament
Insertion:
posterior surface of calcaneous bone through common tendon: calcaneal/achilles tendon
What is the action of the Plantaris muscle?
Weak flexor of knee
Weak plantar flexor of ankle
Active plantar flexion of foot (?)
What is the innervation of the Plantaris muscle?
Tibial nerve
L4,L5, S1-3
What is the origin and insertion of the Popliteus muscle?
Origin:
Lateral condyle of the femur and lateral meniscus of knee joint
Insertion:
Posterior surface of tibia
What is the action of the Popliteus muscle?
-Weak plantar flexor
-UNLOCKS THE KNEE
rotates femur laterally in a weight bearing leg (must be done before knee can be flexed)
What is the innervation of the Popliteus muscle?
Tibial nerve
L4,L5, S1-3
What is the origin and insertion of the Flexor Digitorum Longus muscle?
Origin:
Middle part of tibia
Insertion:
Distal phalanges of the lateral 4 digits
What is the action of the Flexor Digitorum Longus muscle?
Plantar flexes the foot
Flexes lateral 4 digits
What is the innervation of the Flexor Digitorum Longus muscle?
Tibial nerve
L4,L5, S1-3
What is the origin and insertion of the Tibialis posterior muscle?
Origin:
interosseous membrane, tibia, and fibula
Insertion:
- Plantar surface of the navicuar bones (primary)
- Cuniform bones
- Cuboid bones
- bases of distal 2nd 3rd and 4th metatarsals
What is the action of the Tibialis posterior muscle?
Inverts and Plantar Flexes foot
What is the innervation of the Tibialis posterior muscle?
Tibial nerve
L4,L5, S1-3
What is the origin and insertion of the Flexor hallucis longus muscle?
Origin:
Fibula and interosseous membrane
Insertion:
Distal phalanx of big toe
What is the action of the Flexor hallucis longus muscle?
Flexes big toe
Plantar flexes foot
What is the innervation of the Flexor hallucis longus muscle?
Tibial nerve
L4,L5, S1-3
Which muscle of the superficial compartment does not act on the knee at all and why?
Soleus (attached only to tibia and fibula)
What is the main push off muscle during walking and running
flexor hallucis longus
While the leg is weight bearing what must be done before the knee can be flexed? What does this?
Femur most be rotated laterally
Done by popliteus
What muscles attach to the achilles tendon?
Gastrocnemius
Soleus
Plantaris
What muscle is sometimes absent from the posterior leg muscles
Plantaris
What is the main action of muscles of the anterior leg and what innervates them?
Dorsiflection of the foot and extension of toes
Deep Fibular nerve
L4, L5, S1, S2
What is the main action of muscles of the lateral leg and what innervates them?
active in eversion of foot
assist in plantar flexion
Superficial fibular nerve
(L4, L5, S1, S2)
What is the main action of muscles of the posterior leg and what innervates them?
Plantar flexion of the foot
Tibial Nerve
L4, L5, S1-S3
What is the shape of the inferior retinaculum and where does it attach
y shaped
Base lateral 2 arms medial
Base: lateral side of calcaneus
Upper arm: medial malleolus
Lower arm: blends with deep fascia
What is the popliteal fossa?
diamond shaped intermuscular space posterior to the knee joint
What bounds the popliteal fossa superolaterally?
Biceps femoris (long and short heads)
What bounds the popliteal fossa superomedially?
Semitendinosus and semimembranosus
What bounds the popliteal fossa inferiorly
Medial and lateral heads of gastrocnemius
What makes up the Floor/Anterior wall of the Popliteal fossa?
Popliteal surface of femur
Post. capsule of knee joint
Popliteus muscle
What makes up the Roof/Posterior wall of the Popliteal fossa?
Skin and fascia
What are all the boundaries of the Popliteal fossa
Superomedial:
Semitendinosus and semimembranosus
Superolateral: Biceps femoris (long and short heads)
Inferior:
Medial and lateral heads of gastrocnemius
Roof/posterior:
Skin and fascia
Floor/anterior:
Popliteal surface of femur
Post. capsule of knee joint
Popliteus muscle
What is contained within the Popliteal fossa (6)
-Popliteal artery
-Genicular branches (of popliteal artery)
-Popliteal vein
-Small Saphenous vein
-Tibial Nerve
-Common fibular nerve
PCS GTP or SGT PCP
What are the most superficial and deepest structures of the popliteal fossa
Superficial:
tibial and common fibular nerves
Deep:
Popliteal artery
What is the saphenous nerve a branch of and were does it arise/pass
terminal branch of femoral nerve
emerges at medial side of knee and passes down anteromedial aspect of leg
What does the saphenous nerve supply
skin on medial side of knee and anteromedial aspect of leg
What forms the sural nerve?
Contributions from tibial and common fibular nerves
What does the sural nerve supply
skin on the posterolateral leg and lateral foot
Where does the sciatic nerve divide
in inferior 1/3rd of posterior thigh before entering popliteal fossa
What runs with th small saphenous vein on the posterior aspect of the leg
Sural nerve
How does the Common fibular nerve leave the popliteal fossa and what does it give off
Over lateral head of gastrocnemius
(giving off articular branches to knee and contribution to sural)
Then anteroinferiorly around fibular head to enter lateral compartment
When the Common fibular nerve enters the lateral compartment what does it do
divides into superficial and deep fibular nerves
What does the superfical branch of the common fibular nerve supply
Lateral compartment of the leg
What does the deep branch of the common fibular nerve supply
anterior compartment of the leg
How does the tibial nerve leave the popliteal fossa and what does it give off
(gives off contribution to sural in fossa)
continues downward into posterior compartment in association w/ transverse intermuscular septum and passes posterior to medial malleolus
What happens to the tibial nerve as it passes posterior to the medial malleolus
divides into medial and lateral plantar neres
What does the politeal artery give off in to popliteal fossa
- Paired superior geniculate arteries
- Middle geniculate artery
- Paired inferior geniculate arteries
What do the geniculate arteries provide and do
Provide for the knee joint and anastomose around it
What does the popliteal artery do after giving off geniculate branches
divide into anterior and posterior tibial arteries
What does the anterior tibial artery supply and how does it get there
supplies anterior compartment of the thigh
passes through interosseous membrane
What does the anterior tibial artery become as it continues over the ankle joint
dorsalis pedis artery
What does the posterior tibial artery travel with and give off
travels with with tibial nerve deep to the origin of the soleus
and gives off fibular artery laterally
Where does the fibular artery travel and what does it supply
descends distally in lateral part of posterior compartment
suplies the lateral part of posterior compartment and the lateral compartment
What happens to the tibial artery as it passes the medial malleolus
enters foot as lateral and medial plantar arteries
What are the superficial veins of the leg continuous with
dorsal venous arch of the foot
What arises from the medial aspect of the dorsal venous arch of the foot and what does it drain
Great saphenous vein (has numerous valves)
drains much of the leg
What does the great saphenous vein empty into
Femoral vein at the saphenous opening
What accompanies the great saphenous vein in the leg
saphenous nerve
What arises from the lateral aspect of the dorsal venous arch of the foot and what does it drain
small saphenous vein
drains posterior surface of the leg and gives off communications to great saphenous vein and deep veins
how does the small saphenous vein communicate with the great saphenous vein and deep veins? What do they contain?
via perforating veins
contain valves that prevent return of blood to the superficial veins
Where does the small saphenous vein empty into
Popliteal vein in the popliteal fossa