By General Info
The knee is a complex joint that flexes, extends, and twists slightly from side to side.
The knee is the meeting point of the femur in the upper leg and the tibia in the lower leg. The fibula, the other bone in the lower leg, is connected to the joint but is not directly affected by the hinge joint action. Another bone, the patella, is at the center of the knee.
Two concave pads of cartilage called menisci minimize the friction created at the meeting of the ends of the tibia and femur.
There are also several key ligaments, a type of fibrous connective tissue, that connect these bones. The four key ligaments of the knee are:
Anterior cruciate ligament (ACL)
Medial collateral ligament (MCL)
Lateral collateral ligament (LCL)
Posterior cruciate ligament (PCL)