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Patello-Femoral Syndrome

  • Definition

    Patello-Femoral Syndrome is one of the most common causes of knee complaints, particularly among adolescents and young adults.


    The knee is a complex joint that not only bends and straightens but also twists and rotates. The knee is not a simple ball-and-socket joint, like the hip. It depends heavily on the soft tissues that surround it, the muscles, tendons, and ligaments because it is a weight-bearing joint that is subjected to many different types of motion. This variety of motion can lead to tearing of the cushioning cartilage inside the knee and supporting ligaments on both sides of and inside the knee.

    Because of its structure, the knee is extremely susceptible to blows from the side. It also can be severely damaged by rotating, twisting forces. The joint is well designed for its intended functions but it is the most poorly designed of all joints in the body to withstand the forces of athletics.

    The knee is the most commonly injured joint in the body, accounting for about one-quarter of all injuries. About one million knee surgeries are performed each year.

    The syndrome frequently gives rise to a complaint of pain in the front of the knee. The belief that roughening of the cartilage on the patella's (kneecap) back surface causes the syndrome is erroneous.


    Most common in adolescents and young adults, the predisposing factors include imbalance of quadricep muscle strength, direct trauma to the patella, and injuries of the menisci (pads between the bones in the knee).


    Patients usually have pain in the front of the knee, around or beneath the knee cap. Patients may have difficulty going up or down stairs. Also, after remaining seated for a prolonged time, they may experience extreme discomfort with their first few steps after rising. The symptoms improve with further walking. They may also complain of joint locking or the feeling of joint instability.


    The medical history including signs and symptoms is key. Physical exam shows no signs of inflammation (red, swollen joint).


    Physical therapy may be helpful in some circumstances but is usually not needed.


    How serious is it?

    What type of treatment will you be recommending?

    How long is the treatment?

    Will some activities need to be restricted?

    What type of exercises do you suggest?

    How can further damage be prevented?

    Exercises can help strengthen the inner side of the quadriceps muscle. The muscle in the front of the thigh hooks in the kneecap and helps align it into the center of the groove. The quadriceps can be strengthened by a full leg extension exercise.

    If the patient is doing leg-strengthening routines, it is necessary to stay away from leg presses and squats which put stress on the bent knee. Bending the knee more than 30 degrees may cause symptoms to flare up.

    The same principle goes for riding an exercise bicycle. The seat should be high enough to bend the knee as little as possible (allowing nearly full extension). Although most cases respond to these conservative interventions, some persist for years. Conservative therapy is still encouraged and operation is rarely indicated.

    Avoid exercise that places undue stress on the knee, like deep knee-bends. Also, while cycling, make sure that the seat is at an adequate height. If in doubt, check with your local cycle shop for seat height guidelines for you.