Knee Pain

The thigh bone (femur) meets the large shin bone (tibia) forming the major knee joint. This joint has an inner (medial) and an outer (lateral) section. The kneecap (patella) joins the femur to structure a third joint, called the patellofemoral joint.

The knee joint is bounded by a joint capsule with ligaments strapping the inside and outside of the joint (collateral ligaments) as well as crossing within the joint (cruciate ligaments). These ligaments give stability and strength to the knee joint.

The meniscus is a thickened cartilage pad between the two joints shaped by the femur and tibia. The meniscus acts as a flat surface for the joint to move on. The knee joint is surrounded by fluid-filled sacs called bursae, which serve as gliding surfaces that decrease friction of the tendons. Under the kneecap, there is a large tendon (patellar tendon) which attaches to the front of the tibia bone. There are large blood vessels passing throughout the area behind the knee (referred to as the popliteal space). In the front of the thigh, the quadriceps muscles enlarge the knee joint. In the back of the thigh, the constrain muscles flex the knee. The knee also rotates a little under guidance of specific muscles of the thigh.