There are four bones that come together at the knee, the femur (thigh bone), the tibia (shin bone), the head of the fibula (bone on the outside of the leg) and the patella (kneecap). Two major muscle groups, quadriceps and hamstrings, cross the knee and allow for movement of the knee joint. Tendons attach these muscles to the tibia. Thick bands of tissue, called ligaments, stabilize the knee joint, preventing the joint from sliding sideways or back and forth and allowing the muscles of the knee flex and extend.
Inside the knee, there are two shock-absorbing pieces of cartilage, called menisci that prevent the bones from rubbing on each other. Without the menisci, the friction of bone on bone would cause inflammation. There are also fluid filled sacs, called bursas that surround the knee joint and cushion the knee during its range of motion.
With such a complex system in the knee area, it is highly susceptible to injuries and disease. Physical therapy treatments for knee pain aim to reduce pain, and restore and improve normal function. Physical therapy treatments for knee pain may include ultrasound, stretching and/or strengthening, patient education about the intricate mechanics of the knee, and pain management techniques.