The common peroneal (or fibular) nerve is a branch that arises from the sciatic nerve (the largest peripheral nerve in the body). The motor functions of the common peroneal nerve are dorsiflexion at the ankle and toe extension (via its deep fibular branch) and eversion at the ankle (via the superficial fibular branch). In its path, after branching laterally from the sciatic nerve, it then hugs the neck of the fibula before splitting into the deep and superficial peroneal nerves. Clinically, it is commonly compressed when patients cross their legs, thus applying a lateral pressure on the nerve as it passes over the fibular neck.