MICROANATOMY

Detailed explanation-1: -The knee flexors include the set of hamstrings, gracilis, sartorius, gastrocnemius, plantaris, and popliteus . Most of these knee flexors also internally or externally rotate the knee. The hamstring muscles are the primary knee flexors.

Detailed explanation-2: -The four muscles of the quadriceps: vastus lateralus, vastus medialus, vastus intermedius and rectus femoris function to extend the knee.

Detailed explanation-3: -The knee extensors play an essential role in human movement. The one agonist muscle that extends the knee is the massive quadriceps. Knee extension ROM is from full flexion to 5-10° hyperextension. The iliotibial tract (ITB) and tensor fascia latae (TFL) also play a role in knee extension.

Detailed explanation-4: -At the knee joint, flexion and extension are the main movements, which are caused by the quadriceps group of muscles. This group consists of four muscles – rectus femoris, vastus medialis, vastus intermedius and vastus lateralis – and is located on the anterior thigh.

Detailed explanation-5: -All of the following muscles flex the knee except for the D. vastus medialis. The vastus medialis is a muscle in the quadricep group that functions to extend the leg at the knee joint.