What is patellofemoral pain syndrome?
Patellofemoral pain syndrome is pain behind the kneecap. It has been given many names, including chondromalacia, patellofemoral disorder, patellar malalignment, and runner's knee.
How does it occur?
Patellofemoral pain syndrome can occur from overuse of the knee in sports and activities such as running, walking, jumping, or bicycling.
The kneecap (patella) is attached to the large group of muscles in the thigh called the quadriceps. It is also attached to the shin bone (bone in lower leg) by the patellar tendon. The kneecap fits into grooves in the end of the thigh bone (femur) called the femoral condyle. With repeated bending and straightening of the knee, you can irritate the inside surface of the kneecap, resulting in pain.
Patellofemoral pain syndrome also may result from the way your hips, legs, knees, or feet are aligned. This alignment problem is commonly caused by having feet with arches that collapse when walking or running. This condition is called over-pronation. Over-pronation is common in children. Looking at your child from the rear, the ankles will appear to flare outwards and your child will appear to be walking on the inside of the foot.
Other causes include having underdeveloped thigh muscles, wider hips, or being knock-kneed.
What are the symptoms?
The main symptom is pain behind the kneecap. You may have pain when you walk, run, or sit for a long time. The pain is generally worse when walking downhill or down stairs. Your knee may swell at times. You may feel or hear snapping, popping, or grinding in the knee.
How is it diagnosed?
The diagnosis can be made after reviewing the symptoms and examining the knee. X-rays are rarely necessary.
How is it treated?
Treatment includes the following:
1. Place an ice pack on your knee for 20 to 30 minutes every 3 to 4 hours for the first 2 to 3 days or until the pain goes away,
2. Elevate your knee by placing a pillow underneath your leg when your knee hurts.
3. Take anti-inflammatory medication, such as ibuprofen, as prescribed by your doctor.
4. Do the exercises recommended by your doctor or physical therapist (see diagrams below).
Your doctor may recommend that you:
1. Wear custom-made arch supports (orthotics) to correct for over-pronation.
2. Use an infrapatellar strap, a strap placed beneath the kneecap over the patellar tendon.
3. Wear a neoprene knee sleeve, which will give support to your knee and patella.
While you are recovering from your injury, you will need to change your sport or activity to one that does not make your condition worse. For example, you may need to bicycle or swim instead of run. In cases of severe patellofemoral pain syndrome, surgery may be recommended.
When can I return to my sport or activity?
The goal of rehabilitation is to return you to your sport or activity as soon as is safely possible. If you return too soon you may worsen your injury, which could lead to permanent damage. Everyone recovers from injury at a different rate. Return to your sport or activity will be determined by how soon your knee recovers, not by how many days or weeks it has been since you were injured. In general, the longer you have symptoms before you start treatment, the longer it will take to get better.
You may safely return to your sport or activity when, starting from the top of the list and progressing to the end, each of the following is true:
How can I prevent patellofemoral pain syndrome?
Patellofemoral pain syndrome can best be prevented by strengthening your thigh muscles, particularly the inside part of this muscle group. It is also important to wear shoes that fit well and that have good arch supports.
Written by Pierre Rouzier, M.D., for Clinical Reference Systems
Rehabilitation Exercises for Chondromalecia
(Patellofemoral Pain Syndrome)
Exercising an injured knee properly will help you return to sports sooner and more safely. The following exercises are designed to help regain full knee motion, strength, and balance.
Refer to the diagrams shown below. The hamstring stretch (exercise #1) can be started right away. Patellar motility exercises (#2) can be started as soon as it is not too painful to move your kneecap. When the knee pain has decreased, begin the quadriceps stretch (exercise #3) and start strengthening the thigh muscles using exercises #4 through #6.
Hamstring stretch: Do not round your shoulders and bring your head toward your toe. This will stretch your low back instead of your hamstrings.
Straight leg raise:
Weight lifting - leg extension:
Written by Tammy White, M.S., P.T., for Clinical Reference Systems