Saphenous Nerve Entrapment as a source of knee pain

At the Centeno-Schultz Clinic we acknowledge that there can be many causes of knee pain.

In our online book, Ortho 2.0 a systematic approach is discussed: SANS.

N references neurologic dysfunction.

Irritation or dysfunction of the saphenous nerve can be cause of knee pain.

The saphenous nerve is a pure sensory nerve compromised of fibers from L3 and L4.  The saphenous nerve is the longest branch of the femoral nerve.

Branches

Above the knee joint the infrapatellar branch arises whereas below the knee the medial crural cutaneous branch provide sensation to the front and medial aspect of the knee.

A common site of entrapment is adductor (Hunter’s) canal which is an aponeurotic tunnel in the middle third of the thigh.  Adductor canal contains femoral artery, femoral vein and branches of the femoral nerve which include the saphenous nerve.

The Adductor canal has the following boundaries:

• Anteriorly – Sartorius
• Postermedially – adductor longus and adductor magnus
• Laterally -vastus medialis

adductor canal

Ultrasound image of saphenous nerve in Adductor canal

A systematic approach with diagnostic tools that include MSK ultrasound ensure maximal patient outcomes.  Treatment options of saphenous nerve irritation/entrapment include MSK ultrasound guided hydrodissection with platelet growth factors.