Posterior compartment of the leg Flashcards
What is the proximal attachment of the gastrocnemius?
Lateral head: lateral condyle of femur
Medial head: popliteal surface of femur
What is the distal attachment of the gastrocnemius, soleus, and plantaris?
Posterior surface of calcaneus via calcaneal tendon
What nerve innervates the gastrocnemius, soleus, and plantaris?
Tibial nerve (S1,S2)
What is the main action of the gastrocnemius?
- Plantarflexes ankle
- Raises heal when walking
- Flexes leg at knee joint
What is the proximal attachment of the soleus?
Head of fibula, soleal line and medial border of tibia, tendinous arch
What is the main action of the soleus?
- Plantarflexes ankle independent of position of knee
- Steadies leg on foot
What is the proximal attchment of the plantaris?
Supracondylar line of femur and oblique popliteal ligament
What is the main action of the plantaris?
Weakly assists gastrocnemius in plantarflexing ankle
What is the proximal attachment of the popliteus?
Lateral surface of condyle of femur and lateral meniscus
What is the distal attachment of the popliteus?
Tibia superior to soleal line
What nerve innervates the popliteus?
Tibial nerve (L4,L5,S1)
What is the main action of the popliteus?
- Weakly flexes knee
- Medially rotates tibia of unplanted limb
What is the proximal attachment of the flexor hallucis longus?
Posterior surface of fibula; inferior part of interosseous membrane.
What is the distal attachment of the flexor hallucis longus?
Distal phalanx of great toe (hallux)
What nerve innervates the flexor hallucis longus and flexor digitorum longus?
Tibial nerve (S2,S3)
What is the main action of the flexor hallucis longus?
- Flexes great toe
- Weakly plantarflexes ankle
- Supports medial longitudinal arch of foot
What is the proximal attachment of the flexor digitorum longus?
Tibia inferior to soleal line, by a broad tendon of fibula
What is the distal attachment of the flexor digitorum longus?
Distal phalanges of lateral four digits
What is the main action of the flexor digitorum longus?
- Flexes lateral 4 digits
- Plantarflexes ankle
- Supports longitundinal arches of foot
What is the proximal attachment of the tibialis posterior?
Interosseous membrane, tibia, posterior surface of fibula
What is the distal attachment of the tibialis posterior?
Tuberosity of navicular, cuneiform, cuboid, and sustentaculum tali of calcaneus; bases of 2nd, 3rd, and 4th metatarsals
What nerve innervates the tibialis posterior?
Tibial nerve (L4,L5)
What is the main action of the tibialis posterior?
- Plantarfelxes ankle
- Inverts foot
