The Leg Flashcards
Compartments of the leg
Anterior, lateral, posterior compartments
Which structure separates the anterior and posterior compartments?
Interosseous membrane
Which structure separates the anterior and lateral compartments?
Anterior intermuscular septum
Which structure separates the lateral and posterior compartments?
Posterior intermuscular septum
The strong, broad band of deep fascia, passing from the fibula to tibia, proximal to the malleoli to prevent anterior bowstringing of the tendons during dorsiflexion
Superior extensor retinaculum
Function of the retinaculum on the ankle joints
Prevents ankle joints from bowstringing anteriorly during dorsiflexion of the joint
The Y-shaped band of deep fascia that attaches to the anterosuperior surface of the calcaneous to loop aroung the tendons of the fibularis tertius and the extensor digitorum longus muscles
Inferior extensor retinaculum
Dorsiflexion of the ankle has a range of how much from neutral?
about 20 degrees
Which muscle controls the lowering of the forefoot to the floor following heel strike?
Tibialis anterior
The most medial and superficial dorsiflexor
Tibialis anterior
The strongest dorsiflexor
Tibialis anterior
Tibialis anterior and tibialis posterior are synergists in flexing the ankle. T/F
F
They are antagonists at the ankle joint, but synergists in inverting the foot.
Muscle that acts as synergist to tibialis anterior when inverting the foot
Tibialis posterior
Most lateral of the anterior leg muscles
Extensor digitorum longus
The muscle whose tendon attaches to the 5th metatarsal instead of to a phalanx
Fibularis tertius
Fibularis tertius is not always present. T/F
T
Innervation of the anterior compartment
Deep fibular nerve
Actions of the tibialis anterior
Dorsiflexes ankle,
Inverts foot
Actions of fibularis tetrius
Dorsiflexes ankle,
Everts foot
Actions of extensor digitorum longus
Dorsiflexes ankle,
Extends lateral four digits
Actions of extensor hallucis longus
Dorsiflexes ankle,
Extends big toe
Extensor hallucis longus is deep between which muscles superiorly?
Tibialis anterior and extensor digitorum longus
Innervation of the tibialis anterior
Deep fibular nerve
Innervation of the fibularis tertius
Deep fibular nerve
Innervation of extensor digitorum longus
Deep fibular nerve
Innervation of extensor hallucis longus
Deep fibular nerve
The deep fibular nerve is a branch of which nerve?
Common fibular nerve
The terminal branches of the common fibular nerve
Superficial fibular (peroneal) nerve and deep fibular (peroneal) nerve
The deep peroneal nerve arises between which structures?
The fibularis longus muscle and the neck of the fibula
The deep peroneal nerve accompanies which muscle when it enters the anterior compartment?
Tibialis anterior
Proximally, the deep peroneal nerve is between which muscles?
Tibialis anterior and extensor digitorum longus
Distally, the deep peroneal nerve is between which muscles?
Tibialis anterior and extensor hallucis longus
The deep fibular nerve innervates which structures
Anterior muscles of the leg (TA, EHL, FT, EDL), dorsum of foot, skin of first interdigital cleft, joints it crosses
Lesion of the deep fibular nerve results in which inability?
Dorsiflex ankle (foot drop)
Which artery supplies the anterior compartment?
Anterior tibial artery
Arterial supply of the fibularis tertius
Anterior tibial artery
Arterial supply of the extensor digitorum longus
Anterior tibial artery
Arterial supply of the extensor hallucis longus
Anterior tibial artery
Arterial supply of the tibialis anteior
Anterior tibial artery
The anterior tibial artery supplies which muscles?
Anterior compartment (tibialis anterior, fibularis tertius, extensor digitorum longus, extensor hallucis longus)
The anterior tibial artery is the smaller terminal branch of which artery
Popliteal artery
At the ankle joint, midway between the malleoli the anterior tibial artery becomes which artery?
Dorsal pedis artery
The smallest (narrowest) compartment of the leg
Lateral compartment
The lateral compartment ends inferiorly with the superior extensor retinaculum. T/F
F
It ends with the superior fibular retinaculum.
The superior fibular retinaculum spans which structures?
The distal tip of the fibula and the calcaneous
The fibularis brevis and fibularis longus enter a common synovial sheath to accommodate their passage between the superior fibular retinaculum and the lateral malleolus. T/F
T
Muscles of the lateral compartment
Fibularis longus, fibularis brevis
Action of the muscles of the lateral compartment
Evertion of the foot, Plantarflexes ankle (weakly)