Which muscle flexes the knee joint?

The hamstring is the main muscle that flexes the knee. The knee joint actually consists of two joints, the tibiofemoral joint and the patellofemoral joint, which work together to give a wide range of motion, including flexing, extending and rotating the knee.

The knee joint, which connects the thigh bone to the shin bone, can flex, extend and rotate. These movements are controlled by the hamstring, the calf muscles and the quadriceps. The tensor fasciae latae, popliteus and the articularis genus muscles aid in the movement of the knee as well. These muscles work together to stabilize the knee joint.