[Music] so the gastrocnemius muscle which is also called the calf muscle is a very strong and superficial muscle that's found in the posterior compartment of the leg alongside the deeper soleus muscle and the plantaris muscle and those three together complete the superficial posterior compartment of our leg so the gastrocnemius has got two heads it has a medial head and a lateral head the medial head attaches to the posterior portion of the medial femoral condyle the lateral head attaches to the posterior part of the lateral femoral condyle from its origin it then inserts along with the soleus and plantaris muscle via the calcaneal tendon into the posterior surface of the calcaneus bone now because this muscle originates above the knee joint and it extends to the calcaneum it's got actions both on the knee and the ankle now it's primary action is to plantar flex the foot at the ankle joint but it also assists with flexion of our knee in terms of its nerve supply the gastrocnemius is innervated by the tibial nerve you can see how the tibial nerve here is a continuation of the sciatic nerve so here's the tibial nerve and here is the sciatic nerve so the tibial nerve runs obviously posteriorly and between the two heads of the gastrocnemius muscle you can see how it runs anterior to the gastrocnemius and then runs around the medial portion of the ankle in terms of its blood supply the gastrocnemius gets its blood supply off of the popliteal artery so the popliteal artery is a continuation of the superficial femoral artery which runs down the antero medial portion of our thigh so you can see how the popliteal artery sort of carries on from the superficial femoral artery and then it kind of goes through the two heads of the gastrocnemius just like the tibial nerve does and the actually what happens is that the popliteal artery gives off small branches so here there are small branches that come off backwards or posteriorly that are called the sural branches and that is the blood supply to the gastrocnemius muscle so i hope you found this tutorial useful if you have please give us a like and subscribe make sure to watch out for our next video on gastrocnemius injury and rehabilitation and thank you for watching