Patellar Tracking Disorder

Patellar tracking disorder means that 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. In a few people, it shifts toward the inside.

Your knee joint is a complex hinge that joins the two bones of the lower leg with the thigh bone. The kneecap sits in a groove at the end of the thigh bone. It is held in place by tendons on the top and bottom and by ligaments on the sides. A layer of cartilage lines the underside of the kneecap. This helps it glide along the groove in the thigh bone.

A problem with any of these parts in or around the knee can lead to patellar tracking disorder.

You are more likely to have patellar tracking disorder if you have any of the problems below and you are overweight, run or play sports that require repeated jumping, knee bending or squatting. Common causes are:

• Weak thigh muscles
• Tendons, ligaments or muscles in the leg that are too tight or too loose
• Activities that repeatedly stress the knee, especially those with twisting motions
• A traumatic injury to the knee, such as a blow that pushes the kneecap toward the outer side of the leg
• Problems with the structure of the knee bones or how they are aligned

If you have a patellar tracking problem, you may experience:

• Pain in the front of the knee, especially when you squat, jump, kneel or use stairs (most often when going down stairs).
• A feeling of popping, grinding, slipping or catching in your kneecap when you bend or straighten your leg.
• A feeling that your knee is buckling or giving way, as though all of a sudden your knee can’t support your weight.
• If your kneecap is completely dislocated, you may have severe pain and swelling. Your knee may look like a bone is out of place, and you may not be able to bend or straighten the knee. If you have these symptoms, see your doctor. A dislocated kneecap needs to be put back in place by a doctor right away.

It can be hard to tell the difference between patellar tracking disorder and some other knee problems. 

To find out what problem you have, your doctor will:

• Ask questions about your past health, your activities, when the pain started and whether it was caused by an injury, overuse or something else.
• Feel, move and look at your knee as you sit, stand and walk.
• Potentially recommend an X-ray to check the position and condition of your knee bones.
• Order an MRI, if more information is needed.

Patellar tracking disorder can be a frustrating problem, but be patient. Most people feel better after a few months of treatment. As a rule, the longer you have had this problem, the longer it will take to get better.

Treatment of patellar tracking disorder has two goals: to reduce your pain and strengthen the muscles around your kneecap to help it stay in place. If you do not have severe pain or other signs of a dislocated kneecap, you can try home treatment for a week or two to see if it will reduce your pain. It is generally recommended that you:

• Take a break from activities that cause knee pain, like squatting, kneeling, running and jumping.
• Put ice on your knee, especially before and after physical activity. After two or three days, you can try heat to see if that helps.
• Take an over-the-counter pain reliever such as ibuprofen or naproxen to reduce pain and swelling. Read and follow all instructions on the labels.
• As your knee pain starts to decrease, do exercises to increase strength and flexibility in your leg and hip. Your doctor or a physical therapist can help you plan an exercise program that fits your condition. You will probably start with one or two exercises and add others over time. Make sure to closely follow the instructions you are given.

Your doctor or physical therapist may also suggest that you:

• Tape your knee to hold the kneecap in place.
• Use a knee brace for extra knee support.
• Try shoe inserts (orthotics) to improve the position of your feet.

Most people with patellar tracking disorder can slowly return to their previous activity level if they:

• Avoid movements that make symptoms worse.
• Keep doing their stretches and strength exercises.
• Learn the best way to play their sport and use the right shoes or equipment.
• Lose excess weight.

Surgery is not usually needed for patellar tracking disorder. But you may need surgery if your kneecap dislocates after other treatments have not worked. There are several types of surgery that can correct a patellar tracking problem. You and your doctor can decide which surgery is best for you.

You can take steps to prevent patellar tracking disorder:

• Avoid activity that overloads and overuses the knee.
• Keep the muscles around your knees and hips strong and flexible.
• Stretch your legs and hips well, both before and after physical activity.
• Do activities that work different parts of the leg, such as cycling and swimming, especially if you are a runner. 
• Stay at a healthy weight to reduce stress on your knees.