ANTERIOR (FRONT) KNEE PAIN

CONDITION

Anterior knee pain, pain over the front of the knee, is the most common type of knee pain. There are many causes (Figure 1 below), although a few conditions are responsible for most problems. Anterior knee pain occurs in people of all ages and usually responds to non-surgical treatment and rehabilitation.

Causes

Injuries can be the result of one event or due to overuse:

a direct fall or impact (for example, with the dashboard in a car accident) on the front of the knee
a sudden increase in intensity, duration or frequency of sports or exercise
beginning a new sports activity, especially an activity involving running and jumping
frequent bending and squatting.

During their growing years, children are vulnerable to growth plate injuries that can lead to anterior knee pain. And, at any age, anterior knee pain can result from the way your body is made. You may have:

kneecaps that are higher or lower than normal, knock knees or flat feet
tight hamstrings (the large muscles over the back of your thigh), tight quadriceps (the large muscles over the front of your thigh) or tight calf muscles and tendons
under-developed quadriceps muscles.

Symptoms and Signs

Signs and symptoms depend on the type of injury.

Patellofemoral pain syndrome (pain between the kneecap and the bone above the knee):

You will have pain over, under or around the kneecap.
Your symptoms usually develop and worsen slowly during and after overuse activities such as running, jumping, stair climbing or squatting.
You may notice mild swelling around the kneecap.
You often have knee stiffness after you get up from a sitting position, especially if your knee was bent.
The pain may be worse when your knee is bent or flexed, such as when you cross your legs.
You sometimes notice popping or snapping around the kneecap.
You may have a sense of your knee giving out with weight-bearing activities.

Kneecap dislocation (kneecap displacement):

You will have immediate, severe knee pain, usually after suddenly twisting, cutting or falling during sports.
You may notice that you knee looks caved in on the inner side of the kneecap.
You may notice a bulge or lump on the outside of the knee where the kneecap is dislocated.
You may feel the kneecap shift back into place when you straighten your knee from a bent position.
You will develop a lot of swelling within an hour or two after your injury.
You will have a hard time putting weight on your knee and leg, and you may feel like your knee is unstable if you try to walk.

If you have crunching or grinding, severe pain, swelling and difficulty putting weight on your knee, your kneecap may be broken.

Quadraceps tendonitis (irritation and inflammation of the fibrous band of tissue that attaches the four muscles on the front of your thigh to the top of your kneecap):

You will notice pain and swelling at the top of or just above your kneecap related to overuse activities such as running, jumping and squatting.
You may notice stiffness or tightness above the kneecap, especially after periods of sitting or rest.

Tear or rupture of the quadriceps tendon happens after a forceful contraction of the quadriceps muscle, usually when landing on the leg while running or falling.

You will have immediate pain and swelling above the kneecap.
Your knee will give out and you will have weakness and difficulty straightening your knee and walking.

Patellar tendonitis, or jumper’s knee (irritation and inflammation of the fibrous band of tissue that attaches your kneecap to your shinbone, or tibia):

You will have pain over the tendon below your kneecap, usually at the point of attachment to the kneecap or just below it.
Your symptoms usually develop and worsen slowly during and after overuse activities such as running, stair climbing, squatting and, especially, jumping.
At first, symptoms may occur only after activities that cause them, but as the condition worsens, you will have symptoms during those activities.
You may notice mild swelling or thickening below the kneecap or a lump in the tendon below the kneecap, which is particularly noticeable when compared to the uninjured side.
You often have knee stiffness after you get up from a sitting position, especially if your knee was bent.
You may have a sense of your knee giving out with weight-bearing activities.

Osgood Schlatter’s Disease, or OSD (an injury to the growth plate at the end of the patellar tendon where it attaches to your tibia):

OSD occurs between ages 8 to 13 years, especially during periods of rapid height gain.
You will have pain and swelling over the tendon below the kneecap where it attaches to the tibia.
Your symptoms usually develop and worsen slowly during and after overuse activities such as running, stair climbing, squatting and jumping.
At first, symptoms may occur only after activities that cause them, but as the condition worsens, you will have symptoms during those activities.

Prepatellar bursitis (an irritation and inflammation of the prepatellar bursa, a fluid-filled sac located at the front of your kneecap):

You will have swelling, pain and, sometimes, redness and warmth directly over the front of your kneecap.
Your symptoms are caused by and often worsen with kneeling or direct pressure over the front of the kneecap.
You may have difficulty and tightness when bending your knee or squatting.

WHEN TO CALL YOUR DOCTOR

Call your doctor right away (night or day) if:

You have severe pain, swelling, redness or warmth in your knee, especially after an injury.
You can’t bend or straighten your knee after an injury.
You have significant knee weakness after an injury, especially when you try to straighten your knee or go down stairs.
You can’t put weight on your knee after an injury.
You heard or felt a loud pop during an injury.
Your knee feels swollen like a balloon.
You hear crunching that occurs with pain when you try to move your knee or to walk.
Your knee gives out, buckles or gets locked, or something catches in the joint when you try to walk after an injury.
You have numbness, tingling or loss of sensation around your knee or anywhere below your knee after an injury.
You are younger than 15 years old and have a limp with knee and/or hip pain.

Call your doctor during regular office hours if after an injury:

You have mild pain and swelling that persists after trying the self-care measures listed below, but:

You have no warmth or redness around your knee.
You can bend your knee well.
You can put weight on your knee and leg without causing a lot of pain.
Your symptoms worsen at any time or fail to improve.

^Back to Top

SELF-CARE AT HOME

Anyone under 15 years old with knee pain and/or swelling that interferes with activity needs to be evaluated by a doctor and should not attempt the self-care measures recommended below. Avoid using any medication to control symptoms until you have been seen by a doctor.

For signs and symptoms listed under patellofemoral pain syndrome, patellar tendonitis, OSD or quadriceps tendonitis, you may try home measure at first, but see your doctor if symptoms worsen or do not improve significantly within two to three weeks.

Rest from all activities that cause symptoms until your knee symptoms resolve. Avoid running, jumping, squatting and climbing stairs. Do quad sets (Figure 2 below) to keep your thigh muscles strong while your knee is recovering.
Figure 2

Sit flat on the floor with your legs straight out in front of you. Place a soft ball or pillow underneath your injured knee. Lift your lower leg until your injured knee is fully straight. Tighten your thigh muscles for three to five seconds, then slowly lower your leg back to floor. Repeat 10 to 15 times and do two to three sets daily
If the exercise above causes knee pain, you may perform modified quad sets. Keeping both knees and legs flat on the floor, tighten the thigh muscles of the injured leg and press the leg directly downward “into” the floor for three to five seconds. Gradually make contractions harder and repeat 10 to 15 times. Do two to three sets daily.

Stretch your hamstrings, quadriceps and calf/heel tendons daily for 20 to 30 seconds, two to three times each.
- Hamstrings: Lie on the floor on your back. Straighten your leg and place a towel or a piece of rope around your foot and pull your leg toward your head (Figure 3 below) until you feel a stretch over your injured hamstring.
- Quadriceps: Stand beside a wall to brace yourself with the hand on your uninjured side. Bend your injured leg so that your foot is behind you. Reach around with the hand on that same side and grasp your foot (Figure 4 below). Pull your heel toward your buttocks until you feel a stretch in the front of your thigh muscles.
- Calf and heel tendons: Take the position in Figure 5 below. Keeping your back leg straight, lean forward toward the wall. Feel the stretch in your calf muscle.
You may take ibuprofen (Advil®, Motrin®) or naproxen (Aleve®) for swelling and pain. (See the labels for dose and risks).
Place an ice pack or cold pack directly over the injured area of your knee. You can hold it in place with an elastic wrap.
- Use the cold pack for 20 minutes at least three times daily or more often if needed to reduce pain and swelling.
- If you are not wearing an elastic wrap directly over your skin, place a thin washcloth between the cold pack and your skin to reduce the risk of frostbite.
- If you are busy, you may choose to ice during meals so as to save time and avoid interrupting other activities.
Once your soreness and swelling starts to get better, you may try riding a stationary bike (using low resistance) for 10 to 20 minutes daily or every other day.
If your knee starts to feel normal within one to two weeks, you may attempt functional drills to see if you are ready to start sports or regular exercise again. You may progress through a series of drills by completing each one pain-free. If you have symptoms with a drill, stop and try again in a day or two.
- Jog a straight 50-yard line at about 50-percent intensity.
- Run a straight 50-yard line at 75-percent, then 100-percent intensity.
- Using the same intensity progressions, run a straight line and progress through 45-degree and then 90-degree cuts to the right and to the left.
- Then, run a large or “loose” figure-of-eight path and gradually make it smaller or “tighter” and faster with repeat attempts.

When you can do all of these drills pain free, you can try sports-specific activity. When you return to specific sports or exercise activity, at first try sports-specific drills or exercise at only 50-percent intensity and in a noncompetitive setting.

Signs and symptoms listed under kneecap dislocation, quadriceps tear, prepatellar bursitis and any moderate to severe knee swelling, locking, catching or giving out should be evaluated by a doctor. Serious injuries can be missed easily, especially with swelling inside the knee joint or redness around the knee joint.

Avoid any running, jumping, twisting or kicking until your knee has been evaluated by a doctor.
If you have pain or a sense of buckling when you try to walk or put weight on your knee or leg, use crutches to take all the weight off your injured knee.
If it hurts when you try to bend your knee, hold it as straight as possible or in the most comfortable position you can find until you see your doctor.
Elevate your injured knee as often as you can by placing it up on a couch or chair when you are sitting or lying down.
Place an ice pack or cold pack directly over the injured area of your knee.
Use a snug elastic wrap or sleeve around your knee to help minimize swelling until it improves greatly or goes away entirely.
Because most over-the-counter knee braces do not help stabilize your knee very well, don’t wear one without advice from your doctor.
Neoprene or elastic knee braces with a hole for the kneecap and a “doughnut” pad around the hole sometimes reduce anterior knee pain.
You may take ibuprofen (Advil®, Motrin®) or naproxen (Aleve®) for swelling and pain. (See labels for dose and risks.)

PREVENTION

Regular exercise that strengthens the muscles around your knee and keeps your weight down can help prevent knee injuries and swelling.
A regular stretching program that focuses on the hips, legs and ankles can help prevent some knee injuries.
Avoid sudden changes or increases in exercise or sporting activities.

^Back to Top

FOR MORE INFORMATION

REFERENCES

Dixit S: Management of patellofemoral pain syndrome. American Family Physician 75(2):194-202, 2007.
Post W: Anterior knee pain: diagnosis and treatment. Journal of American Academy of Orthopaedic Surgeons 13(8):534-43, 2005
Walsh WM, Vanicek JJ: Knee injuries. In Mellion M, Walsh WM, Madden C, et al: Team Physician’s Handbook, p 490-508, Hanley & Belfus, Philadelphia, 2002.

View Anatomic Index of Topics

Authored by Christopher Madden, M.D.

Favorably reviewed by The American Medical Society for Sports Medicine

http://amssm.org

Disclaimer: This content is reviewed periodically and is subject to change as new healthcare information becomes available. The information is intended to inform and educate and is not a replacement for medical evaluation, advice, diagnosis or treatment by a healthcare professional.