The gastrocnemius is a muscle within the superficial compartment of the posterior leg. It has medial and lateral heads and forms the characteristic “calf” shape of the leg. Attachments: The lateral head originates from the lateral femoral condyle. The medial head originates from the medial femoral condyle. The two heads combine to form a single muscle belly. Distally, the muscle belly converges with the soleus muscle to form the calcaneal tendon. This inserts onto the calcaneus. Actions: Plantarflexion at the ankle joint and flexion at the knee joint. Innervation: Tibial nerve. Blood Supply: Medial and lateral sural arteries (branches of the popliteal artery). By TeachMeSeries Ltd (2025) Fig 1The muscles in the superficial layer of the posterior leg. The body of the gastrocnemius has been cut away to expose the underlying musculature. Pro Feature - 3D Model You've Discovered a Pro Feature Access our 3D Model Library Explore, cut, dissect, annotate and manipulate our 3D models to visualise anatomy in a dynamic, interactive way. Learn More Print Article Rate This Article