Saphenous nerve

A major sensory nerve of the leg that plays a vital role in innervating the skin of the lower limb.

The saphenous nerve is a branch of the femoral nerve, primarily responsible for providing sensation to the medial side of the lower leg and foot. It is purely a sensory nerve and does not have a role in motor functions, making it essential for conveying sensory information, such as touch and pain, from this region to the central nervous system.

Terminologia Anatomica

nervus saphenus

System

Nervous system

Function

The primary function of the saphenous nerve is to provide sensory innervation to the skin along the medial aspect of the leg, extending from the knee down to the ankle. By transmitting sensory signals, this nerve plays a crucial role in the body’s ability to detect and respond to environmental stimuli. Through its sensory fibers, the saphenous nerve contributes to proprioception, the body's awareness of the position and movement of its limbs. This is vital in maintaining balance and coordination during movement. Furthermore, as a component of the larger neural network, the saphenous nerve aids in pain perception and protective reflexes, serving the body’s overall safety and responsiveness.

Location

The saphenous nerve originates from the lumbar plexus, specifically via the L3 and L4 nerve roots. After its formation, it descends through the thigh alongside the femoral artery. As it travels, it provides branches to the skin in the anterior thigh. Upon reaching the knee area, the saphenous nerve passes beneath the sartorius muscle and travels down the medial aspect of the leg. It continues its course along the tibial side of the leg, ultimately reaching the foot and innervating the skin of the medial malleolus and the plantar surface of the foot. Thus, its path is characterized by its close association with major blood vessels and its distinct innervation territory.

Did You Know?

The saphenous nerve is the longest cutaneous branch of the femoral nerve.
In clinical settings, injury to the saphenous nerve can lead to numbness or altered sensation in the medial aspect of the leg.
During surgical procedures in the knee or femoral regions, the saphenous nerve is at risk of being inadvertently damaged, which is why its location is carefully considered.
The saphenous nerve is often used as a donor nerve for surgical transplants due to its sensory function.