Which nerve innervates the articularis genu?

Which nerve innervates the articularis genu?

• A. Tibial nerve
• B. Common fibular nerve
• C. Femoral nerve
• D. Obturator nerve

Answer: (C)

The nerve supplying articularis genu is the femoral nerve. This small slip of the vastus muscles is considered part of the quadriceps group, and the quadriceps (rectus femoris, vastus lateralis, vastus medialis, and vastus intermedius) are all innervated by the femoral nerve (L2–L4). Articularis genu runs from the distal anterior femur and inserts into the suprapatellar joint capsule and synovial membrane, pulling the membrane superiorly during knee extension to prevent impingement under the femur. Because its neural supply mirrors that of the quadriceps, the femoral nerve is the correct innervation. The other nerves—tibial (posterior leg muscles), common fibular (anterior and lateral leg compartments), and obturator (medial thigh muscles)—do not innervate this small knee joint slip.

The nerve supplying articularis genu is the femoral nerve. This small slip of the vastus muscles is considered part of the quadriceps group, and the quadriceps (rectus femoris, vastus lateralis, vastus medialis, and vastus intermedius) are all innervated by the femoral nerve (L2–L4). Articularis genu runs from the distal anterior femur and inserts into the suprapatellar joint capsule and synovial membrane, pulling the membrane superiorly during knee extension to prevent impingement under the femur. Because its neural supply mirrors that of the quadriceps, the femoral nerve is the correct innervation. The other nerves—tibial (posterior leg muscles), common fibular (anterior and lateral leg compartments), and obturator (medial thigh muscles)—do not innervate this small knee joint slip.