Which muscle extends the knee and is the medial quadriceps muscle?

Which muscle extends the knee and is the medial quadriceps muscle?

• A. Vastus Medialis
• B. Vastus Lateralis
• C. Rectus Femoris
• D. Vastus Intermedius

Answer: (A)

Extending the knee is the job of the quadriceps group, and the muscle that sits on the inner (medial) side of the thigh is the vastus medialis. When the quadriceps fire, they straighten the knee, and the vastus medialis provides that medial portion of the force. It also helps pull the patella medially, aiding in stable patellar tracking. The other vastus muscles lie laterally (vastus lateralis), centrally (vastus intermedius), or share hip action with the knee (rectus femoris), so they aren’t the medial component. Therefore, the vastus medialis best fits being the knee-extending muscle located medially.

Extending the knee is the job of the quadriceps group, and the muscle that sits on the inner (medial) side of the thigh is the vastus medialis. When the quadriceps fire, they straighten the knee, and the vastus medialis provides that medial portion of the force. It also helps pull the patella medially, aiding in stable patellar tracking. The other vastus muscles lie laterally (vastus lateralis), centrally (vastus intermedius), or share hip action with the knee (rectus femoris), so they aren’t the medial component. Therefore, the vastus medialis best fits being the knee-extending muscle located medially.