Pain in the front of the knee is very common. Pain in the front of the knee – or anterior knee pain will affect people in all age groups. The cause of anterior knee pain will vary based on your age. Understanding the causes of anterior knee pain is very important in order to know how to treat it. Anterior knee pain is particularly common in young women and in many runners.
The symptoms of anterior knee pain vary … some of you might have very mild pain, while some of you might have very severe pain.
Most of you will notice that the front of knee hurts when arising from a seated position, or when walking up and down stairs. Some will describe it as a burning pain. Others might feel clicking or popping. Sitting for a long while will typically be very uncomfortable. If the pain in the front of your knee worsens your knee may start to feel like it wants to give out, or your knee might begin to feel unstable. Many runners with severe anterior knee pain (PFPS) will no longer be able to run, especially downhill. Running downhill is actually more stressful than running uphill. Our heart might ache running uphill… but the front of the knee is under a tremendous amount of stress running downhill.
Why Do I Have Pain In The Front of the Knee?
There are three very distinct groups who suffer from pain in front of the knee.
1. Anterior knee pain causes in young athletes:
- Chondromalacia: Chondromalacia is likely a very early sign of arthritis. It involves softening of the cartilage under your patella (kneecap). As the cartilage softens, it can become irritated with certain activities. Surgery is rarely needed. Physical therapy for lower leg, hip, and pelvic strengthening are often successful at limiting your discomfort. Compression sleeves might help minimize the pain too.
- Plica: A plica is a normal tissue found in 25% of knees. In some patients, the plica tissue becomes thicker and irritated. This will cause pain on the inner side of the patella or kneecap. Most people with pain due to an irritated plica will notice improvement with a period of activity modification, and over the counter medications. Injections can be useful in some cases. Surgical removal of the plica is sometimes needed… but only after all other treatments fail.
- Patella tendonitis: Patellar tendonitis is a common cause of pain in the front of your knee. It is a common overuse injury in sports requiring jumping and quick sprints. Patella tendonitis is common in jumping sports participants and is often referred to as a Jumper’s Knee. The pain of patella tendonitis is in the front of the knee just below the kneecap or patella. It is often very tender to touch. Patella tendinitis can resolve with a period of rest, followed by intensive physical therapy. PRP injections or surgery can be considered in situations where your pain does not improve. Surgery is rarely needed. See this post on patella tendonitis for more information.
- Patella Dislocations : Patella dislocations are far more common than we thought many years ago. Many athletes who feel a pop when they’re on the field may have had a patella dislocation. We cover patella dislocations and instability in this post. If you have patella instability then your patella is not gliding in the groove in the front of the femur the way that it should. The patella can simply be tilted or it could possibly dislocate out of the groove entirely. Physical therapy can be effective in certain individuals. Patella braces might also be effective in some individuals. Other patients will eventually require a procedure to “realign” the patella so it doesn’t dislocate or pop out of its groove
2. Runners Knee: PFPS
- Runners Knee or Patella Femoral Pain Syndrome (PFPS) – Many runners will develop pain in the front of the knee (PFPS). This is usually referred to as a “runner’s knee”. See this post for common causes of knee pain in runners. A hallmark of the runner’s knee is that we often find nothing structurally wrong on the exam or an MRI. Pain in the front of the knee from running is not usually due to arthritis or a plica. Many runners will present with an MRI which shows a meniscus tear – but we know that a meniscus tear is usually NOT the cause of pain in the front of your knee. Most of those meniscus tears in runners can safely be ignored. We now believe that hip/core weakness, leading to excess inward rotation of the femur (see image below) is the likely the cause of PFPS. If you look at the diagram below it shows how your pelvis and hip strength contribute to your kneecap (patella) position which could cause anterior knee pain. Furthermore, surgery is almost never indicated for a runner with pain in the front of their knee. Physical therapy which focuses on hip strengthening, core strengthening and stability can alleviate PFPS symptoms in most runners. Most runners with pain in the front of the knee do not need to stop running.
Coping strategies for runners include:
- A shorter stride
- a higher cadence (number of steps per minute)
- avoiding hilly terrain until pain has lessened.
- Prevention: Keep your glutes/core strong.
3. Anterior knee pain in middle-age:
- Osteoarthritis (OA): Arthritis of the patella causes pain because the cartilage under the kneecap has worn out. Arthritis which only involves the patella in your knee is more common in women. Physical therapy can be very effective in the early stages of osteoarthritis of the patella. Read more about the treatment of early arthritis. Injections and over the counter medications may have a role in some patients. In some situations, when the arthritis is severe a patient will need to consider a replacement of the patella or a total knee replacement if the arthritis is elsewhere within the knee.
How Do You Treat Anterior Knee Pain?
Pain in the front of the knee is usually treated successfully without surgery. Many of you will respond to physical therapy which should focus on your hips, yes, your hips and pelvic muscles as much as it focuses on your thigh muscles. Many people with anterior knee pain also get some relief with :
Physical therapy is effective in managing the pain brought on by most causes of anterior knee pain. In some cases of patella instability, where the kneecap dislocates often we need to consider surgery to reconstruct the ligament which holds the patella in place.
In cases of severe arthritis of the patella, we occasionally need to consider a joint replacement if you do not respond to a compression sleeve, injections, activity modification and physical therapy.
Patella tendonitis or a jumpers knee will usually respond to activity modification and physical therapy. If the pain remains severe, there has been a recent interest in trying PRP injections to regenerate the patella tendon. Surgery, although rarely needed, can be very effective in severe cases of a jumpers knee.
Disclaimer: this information is for your education and should not be considered medical advice regarding diagnosis or treatment recommendations. Some links on this page may be affiliate links. Read the full disclaimer.