posterior compartment superficial muscles of the leg

overview of leg

defined as between the knee and ankle joint

• consists of tibia, fibula and interosseous membrane

• divided into anterior, lateral and posterior compartments

posterior compartment of the leg

organized into two functional layers: superficial and deep

• layers separated by deep fascia

superficial layers of posterior leg

3 muscles: gastrocnemius, plantaris, soleus

• primarily perform knee flexion and plantar flexion

Gastrocnemius

O:

medial head: medial femoral condyle

lateral head: lateral femoral condyle
I: calcaneus via calcaneal tendon
A: knee flexion and ankle plantarflexion
N: tibial nerve

Plantaris

O: lateral supracondylar line of the femur
I: calcaneus via calcaneal tendon
A: weak knee flexion, weak plantar flexion
N: tibial nerve

Soleus

O: soleal line on the tibia and posterior surface of the fibular head
I: calcaneus via calcaneal tendon
A: ankle plantar flexion
N: tibial nerve