Anterior and Lateral Leg and Dorsum of Foot. Flashcards
Where is the interosseous membrane?
Between the tibia and fibula
What is the function of the interosseous membrane?
- Surface of muscle attachment
- Resist downward pull of muscles attached to fibula
What type of joint is the superior tibiofibular joint?
Plane synovial joint
Where does the superior tibiofibular joint lie?
Head of fibula and facet on lateral tibial condyle
What movement occurs at the superior tibiofibular joint?
Slight movement during dorsiflexion of ankle
What is this muscle?
Peroneus longus
What is the origin of the peroneus longus?
Head and upper 2/3 of lateral fibula
What is the insertion of the peroneus longus?
Base of 1st metatarsal and medial cuneiform
What innervates the peroneus longus?
Superficial peroneal nerve (L5,S1,2)
What is this muscle?
Peroneus brevis
What is the origin of the peroneus brevis?
Inferior 2/3 of lateral fibula
What is the insertion of the peroneus brevis?
Tuberosity on lateral side of base of 5th metatarsal
What innervates the peroneus brevis?
Superficial peroneal nerve (L5,S1,2)
What is this muscle?
Tibialis anterior
What is the origin of the tibialis anterior?
- Lateral condyle of tibia
- Superior 1/2 of lateral tibial surface
- Interosseous membrane
What is the insertion of the tibialis anterior?
- Medial and inferior surfaces of medial cuneiform
- Base of 1st metatarsal
What is the innervation of the tibialis anterior?
Deep peroneal nerve (L4,5)
What is the function of the tibialis anterior?
- Dorsiflexes ankle
- Inverts foot
What is this muscle?
Extensor digitorum longus
What is the origin of the extensor digitorum longus?
- Lateral condyle of tibia
- Superior 3/4 of medial surface fibula
- Interosseous membrane
What is the insertion of the extensor digitorum longus?
Middle and distal phalanges of lateral 4 digits
What innervates the extensor digitorum longus?
Deep peroneal nerve (L4,5)
What is the function of the extensor digitorum longus?
- Extends lateral 4 digits
- Dorsiflexion of ankle
What is this muscle?
Peroneus tertius
What is the origin of the peroneus tertius?
- Inferior 1/3 anterior fibula
- Interosseous membrane
What is the insertion of the peroneus tertius?
Dorsum of base of 5th metatarsal
What innervates peroneus tertius?
Deep peroneal nerve (L4,5)
What is the function of the peroneus tertius?
- Dorsiflexes ankle
- Assists in eversion of foot
What is this muscle?
Extensor hallucis longus
What is the origin of the extensor hallucis longus?
- Middle anterior surface fibula
- Interosseous membrane
What is the insertion of the extensor hallucis longus?
Dorsal aspect of distal phalanx of hallux
What innervates the extensor hallucis longus?
Deep peroneal nerve (L4,5)
What is the function of the extensor hallucis longus?
- Extends hallux
- Dorsiflexes ankle
Where does the superior extensor retinaculum attach?
Anterior border of tibia –> lower end of fibula
What are these muscles?
Black - extensor hallucis brevis
Blue - extensor digitorum brevis
What is the common origin of the extensor digitorum brevis and extensor hallucis brevis?
- Superior surface of calcaneus
- Inferior extensor retinaculum
What is the insertion of the extensor hallucis? brevis
Base of proximal phalanx of hallux
What is the insertion of the extensor digitorum brevis?
Long extensor tendons of toes 2-4
What innervates the muscles of the dorsum of the foot?
Deep peroneal nerve L5/S1
