What is patellofemoral pain?
Pain around the front of the knee is often referred to as patellofemoral pain. This pain may be caused by:
- soft cartilage under the kneecap (the patella)
- referred pain from another area such as the back or hip
- soft tissues around the front of the knee
- abnormal alignment of the kneecap
Who is at risk for patellofemoral pain?
- manual laborers
- people who are overweight
In athletes, patellofemoral pain may be caused by strain in the tendons, which connect the kneecap to:
- the lower leg bone (this is the patellar tendon)
- upper leg bone (quadriceps tendon)
- the retinaculum (which supports the kneecap on both the left and right sides).
What are the symptoms of patellofemoral pain?
Your child may experience pain when he or she:
- sits with bent knees
- uses stairs
Your child may also experience:
- knee buckling under his or her weight
- a catching, popping, or grinding sensation when walking, or when the knee is moving
How Boston Children's Hospital approaches patellofemoral pain
Treatment for your child's patellofemoral pain will depend on the underlying cause. At Boston Children's, doctors emphasize the use of exercise to strengthen and stabilize the knee as well as the surrounding muscles. Surgery is recommended in only the most severe cases of patellofemoral pain.
Patellofemoral Pain | Diagnosis & Treatments
How does a doctor know if my child has patellofemoral pain?
Your doctor will conduct a physical exam of your child as well as inquire into your child's medical history. The doctor may perform further tests, including
- x-ray: a diagnostic test that uses invisible electromagnetic energy beams to produce images of internal tissues, bones, and organs onto film
- magnetic resonance imaging (MRI): a diagnostic procedure that uses a combination of large magnets, radiofrequencies, and a computer to produce detailed images of organs and structures within the body.
How do we treat patellofemoral pain?
Treatment depends on the specific problem causing the pain.
If the soft tissues (retinaculum, tendon, or muscle) are the source of the pain, stretching, particularly in the prone (face down) position, can be very helpful.
- One simple stretch is to lie prone, grab the ankle of the affected leg with one hand, and gently stretch the front of the knee. It helps to warm up before doing this, or any other stretch.
Strengthening and supporting the knee
Other treatments may involve:
- exercises to build the quadriceps muscle
- taping the patella
- using a specially designed brace which provides support specific to the problem.
Using ice and non-steroidal anti-inflammatory medications can also be helpful. It is often necessary to temporarily modify physical activities until the pain decreases.
Avoid activities which could make knee pain worse.
- Avoid sitting or kneeling with bent knees for extended periods of time.
- Adjust the seat of the bicycle so that the seat is at an appropriate height, you can spin the pedals without shifting your weight from side to side, and the legs are not fully extended at the lowest part of a pedal cycle.
- Avoid exercises that bend the knee, such as squats.
In more extreme situations, a specific surgical procedure may be needed to help relieve the pain.
- If the cartilage under the kneecap is fragmented and causing mechanical symptoms and swelling, arthroscopic removal of the fragments may be helpful.
- If the kneecap is badly aligned, however, a surgical procedure may be needed to place the kneecap back into proper alignment, thereby reducing abnormal pressures on the cartilage and supporting structures around the front of the knee.
- In some people, particularly those who have had previous knee surgery, there may be a specific painful area in the soft tissue around the kneecap which may require removal.
Preventing patellofemoral pain
- Stretching, particularly in the prone position (face down), will keep the supporting structures around the front of the knee flexible and less likely to be irritated with exercise.
- Proper training, without sudden increases of stress to the front of the knee will help avoid pain.
- Weight reduction and activity modification may be necessary in some people.