Leg and Ankle Region Flashcards
What is the name of the deep fascia of the leg?
Crural fascia
What are the 3 compartments of the leg?
Anterior
Lateral
Posterior
What does the interosseous membrane connect?
Connects the tibia and fibula along interosseous borders
What does the interosseous membrane allow passage of in the upper part and in the lower part?
Upper part: permits passage of anterior tibial vessels into anterior compartment
Lower part: permits passage of perforating branch of fibular artery into anterior compartment
What are the 3 groups of retinacula of the ankle?
- superior and inferior extensor retinacula
- flexor retinaculum
- superior and inferior fibular retinacula
What causes compartment syndrome?
Increase in pressure of facial sheaths causes decreased perfusion
What muscles are contained in the anterior compartment of the leg? What is their blood and nerve supply?
Tibialis anterior
Extensor digitorum longus
Extensor halliucis longus
Fibularis tertius
Supplied by anterior tibial artery
supplied by deep fibular nerve
What is the group action of the anterior compartment of the leg?
Causes dorsiflexion
Technically, it is hyperextension, but is called dorsiflexion. So the anterior compartment causes hyperextension
What compartment of the leg is the tibialis anterior contained in, what is its nerve supply and what is its action?
in the anterior compartment
supplied by deep fibular nerve
dorsiflexes and inverts foot
What compartment of the leg is the extensor digitorum longus in, what is its nerve supply, and what is its action?
in the anterior compartment
supplied by the deep fibular nerve
dorsiflexes foot, extends lateral 4 toes
What compartment of the leg is the extensor hallicus longus in, what is its nerve supply, and what is its action?
in the anterior compartment
supplied by the deep fibular nerve
dorsiflexes foot, extends the great toe
What compartment of the leg is the fibularis tertius in, what is its nerve supply, and what is its action?
in the anterior compartment
supplied by the deep fibular nerve
dorsiflexes and everts foot
What is the anterior tibial artery a branch of, what does it supply, and what does it change its name to at the level of the ankle?
is the smaller of the 2 terminal branches of the popliteal artery (arises at the lower border of the popliteal muscle)
- supplies the anterior compartment
- becomes the dorsalis pedis artery at the level of the ankle
What nerve does the deep fibular nerve arise from, which muscle does it branch off within off of the main nerve, and what artery does it join with to enter the foot?
Arises from the common fibular nerve
-within subtance of fibularis longus muscle
Enters the foot alongside with the dorsalis pedis artery
What muscles are contained in the lateral compartment of the leg? What is the blood and nerve supply of this compartment, and what is their group action?
Fibularis longus
Fibularis brevis
Supplied by branches of the fibular artery
Supplied by superficial fibular nerve
group action is eversion
What compartment is the fibularis longus in, what is its nerve supply, and what is its action?
in lateral compartment
Supplied by superficial fibular nerve
everts and plantar flexes the foot
What compartment is the fibularis brevis in, what is its nerve supply, and what is its action?
in lateral compartment
supplied by the superifcial fibular nerve
everts and plantar flexes the foot
What is the common fibular nerve a branch of, what bone does it wrap around the neck of, and within what muscle does it divide into superficial and deep branches?
is a branch of the sciatic nerve
branches around the neck of the fibula
divides into superficial and deep branches within fibularis longus
What is the superficial fibular nerve a branch of, and what two muscles does it first lie in between?
a branch of the common fibular nerve (divides into these branches within the fibularis longus)
-first lies between the fibularis longus and brevis
What muscles are contained in the posterior compartment of the leg?
Superficial: -gastrocnemius -plantaris -soleus Deep: -Popliteus -flexor digitorum longus -flexor hallucis longus -tibularis posterior
What artery supplies the posterior compartment of the leg? What is its nerve supply of the posterior compartment? What is the group action?
Posterior tibial artery supplies the posterior compartment of the leg
supplied by the tibial nerve
group action is plantar flexion
What compartment of the leg is the gastrocnemius, what is its nerve supply, and what is its action?
in the posterior compartment of the leg
supplied by the tibial nerve
plantar flexes foot at ankle joint and flexes leg at knee joint
What compartment of the leg is the soleus in, what is its nerve supply, and what is its action? Does it cross the knee joint?
in the posterior compartment of the leg
supplied by the tibial nerve
plantar flexes foot
does not cross the knee joint
What tendon is formed by the gastrocnemius bellies plus soleus?
Triceps surae which is the main plantar flexor of the foot
What compartment of the leg is the plantaris muscle in, what is its nerve supply, and what is its action?
In the posterior compartment
supplied by tibial nerve
assists with plantar flexion of foot and flexion of leg at knee joint
What compartment is the popliteus muscle in, what is its nerve supply, what is its action?
in the posterior compartment
supplied by the tibial nerve
medial rotation of the tibia if leg is free, lateral rotation of femur if foot is on ground
(unlocks the knee joint)
What compartment is the flexor digitorum longus in, what is its nerve supply, and what is its action?
in the posterior compartment
supplied by the tibial nerve
flexes toes and plantar flexes the foot
What compartment is the flexor hallucis longus in, what is its nerve supply, and what is its action?
posterior compartment
tibial nerve
flexes great toe and plantar flexes the foot
=note it is on the opposite side of the great toe on the leg, so this muscle and the flexor digitorum longus switch underneath
What compartment is the tibialis posterior in, what is its nerve supply, and what is its action?
posterior compartment
supplied by tibial nerve
inverts and plantar flexes the foot
What is the tibial nerve a branch of, what does it pass behind in the ankle?
a branch of the sciatic nerve
passes behind the medial malleoolus
What artery accompanies the tibial nerve?
the popliteal artery
What are the 2 terminal branches of the popliteal artery, and where does it divide?
anterior tibial artery (supplies anterior compartment of leg)
posterior tibial artery (larger; supplies posterior compartment of leg)
divides at the lower border of the popliteus muscle
What are the 2 major branches of the posterior tibial artery?
Nutrient artery of the tibia
fibular artery
What is the main blood supply for the flexor hallucis longus and the lateral compartment muscles (a branch off of the posterior tibial artery)?
the fibular artery (which descends between tibialis posterior and flexor hallucis longis) is the main blood supply for the flexor hallucis longus and lateral compartment muscles)
On the posterior aspect of the ankle, behind the medial malleolus, what is the medial to lateral arrangement of structures?
-tibialis posterior
-flexor digitorum longus
-posterior tibial artery
-tibial nerve
-flexor hallucis longus
(Tom Dick and Harry)
What structures lie behind the lateral malleolus?
Deep to fibular retinacula:
- fibularis longus
- fibularis brevis
Superficial to fibular retinacula:
-sural nerve
small saphenous vein
On the anterior aspect of the ankle, what is deep to the extensor retinacula from medial to lateral?
Tibialis anterior Extensor hallucis longus anterior tibial artery deep fibular nerve extensor digitorum longus fibularis tertius (Tom Harry Dick)
What lies superficial to the extensor retinacula?
Saphenous nerve and great saphenous vein
and the superficial fibular nerve which supplies skin on top of foot
