What is patellar tracking disorder?
tracking disorder occurs when the kneecap (patella) shifts out of place as the
leg bends or straightens. In most cases, the kneecap shifts too far toward the
outside of the leg, although in a few people it shifts toward the
Your knee joint is a complex hinge that joins the lower
leg bones (tibia and fibula) with the thighbone (femur). The kneecap is held in
place in the front of the knee joint by
tendons on the top and bottom and by
ligaments on the sides. A layer of
cartilage lines the underside of the kneecap, helping
it glide along the groove at the end of your thighbone.
kneecap can shift or rotate off track if the groove is too shallow or if the
cartilage is damaged. Ligaments, tendons, or muscles that are too loose or too
tight may also lead to a misaligned kneecap.
See a picture of the
knee joint .
What causes patellar tracking disorder?
patellar tracking disorder is usually caused by
several problems combined. The shape of the patella; too tight or too loose
muscles and tendons in the leg, foot, or hip areas; damage to cartilage; and overuse may lead to
patellar tracking disorder. See a picture of the
muscles and tendons related to patellar tracking disorder .
severe blow to the inside of a healthy knee can knock a kneecap out of
alignment or, in extreme cases, dislocate it. Symptoms of a dislocated kneecap
include the knee looking misshapen like a bone is out of place, not being able
to bend or straighten the knee, knee swelling, and severe pain.
Sometimes patellar tracking problems run in the family. If you have a
family member with knee pain, you may want to take preventive measures, such as
strengthening your thigh muscles.
What are the symptoms?
If your kneecap is out of
alignment, you may have discomfort or pain, especially when you go down stairs,
sit for a long time, stand up from sitting, or squat. This kind of pain, also
known as patellofemoral pain, may be caused by patellar tracking
You also may feel a popping, grinding, slipping, or
catching of the kneecap when you bend or straighten your leg. Or you may feel
that your knee is buckling or giving way, as though the knee suddenly cannot
support your body weight.
How is patellar tracking disorder diagnosed?
knee problems can be hard to tell apart. Your doctor will ask questions about
your past health and carefully examine you to rule out other conditions. Some
of the questions might be: When and how did the pain start? Did it start on its
own with no direct cause? Or was the pain caused by injury, overuse, or some
other problem with the knee? The doctor will also feel and move your knee as
part of the physical exam.