Common Peroneal Nerve, Posterior View

Description

Posteriorly, the sciatic nerve reaches the popliteal fossa and divides into the tibial nerve medially and the common fibular (peroneal) nerve laterally, with the latter tracking along the biceps femoris tendon toward the fibular head. From that point, the common peroneal nerve wraps around the posterolateral neck of the fibula, lying superficial to the bone before splitting into the superficial fibular and deep fibular branches. The femur, tibia, and fibula provide the bony framework from hip to ankle, while accompanying blue venous channels run in parallel corridors to the major nerve trunks. Relationships are clear. The nerve sits lateral in the fossa. Clinical attention often centers on the common peroneal nerve at the fibular neck because it is tethered and subcutaneous there, a setup for injury with fibular head fractures, tight plaster casts, prolonged leg crossing, or lateral knee trauma. Weakness of ankle dorsiflexion and toe extension (deep fibular nerve) and loss of eversion (superficial fibular nerve) follow predictable patterns, and sensory loss over the dorsum of the foot helps separate peroneal neuropathy from L5 radiculopathy. For surgeons, this posterior-lateral course also frames safe dissection planes during posterolateral approaches to the knee and during decompression for entrapment near the fibular tunnel. Educators can place this illustration directly into lower limb anatomy teaching to anchor the popliteal fossa contents and the peroneal division of the sciatic nerve against familiar landmarks like the hamstrings and fibula. It also supports clinical handouts for orthopedics, sports medicine, and physical therapy when explaining foot drop, nerve conduction study targets, or injection and incision planning around the fibular head. Anatomical accuracy verified by SciePro's Medical Advisory Board.