Figure 1: Medial view of the innervation of the knee. The skin overlying the patella is innervated by the medial cutaneous nerve of the thigh, a branch of the saphenous nerve (thick arrow). The medial joint structures are innervated by a branch of the femoral nerve, the medial retinacular nerve, which, after innervating the vastus medialis, continues distal and then anterior to this muscle, to enter the ligamentous structures of the knee joint (long thin arrow). This nerve lies superficial to the synovium and deep to the medial retinaculum. The saphenous nerve’s infrapatellar and distal branches are shown in their most common variation (short thin arrow). The nerve to the patellar skin is from the medial cutaneous nerve of the thigh (short thick arrow). (With permission, Dellon.com).