Anterior knee pain (patellofemoral pain syndrome)

Pain at the front of the knee and in the kneecap area is often a sign of overuse. This means that the knee has been exposed to too frequent or too much strain without having enough time to adapt to it. This is particularly common as a result of sport – for example running, mountaineering or cycling.

Anterior knee pain cannot be treated causally. However, studies show that regular exercises to strengthen the thigh and hip muscles can help to combat the pain. Athletes with acute knee pain should ideally reduce their training load or take a complete break from training to relieve the strain on the knee.

The pain usually occurs behind or around the kneecap. In medical terms, this is referred to as patellofemoral pain or patellofemoral pain syndrome (PFPS). The term “patellofemoral” refers to the area between the kneecap (patella) and the thigh (femur).

The pain generally starts out as relatively mild but can get worse over time. It tends to be quite dull and mainly occurs when strain is placed on the knee. Pain is particularly common when severely bending the knee or climbing stairs. Sitting down for a long time can also make the knee hurt and feel stiff.

People with knee pain can often hear cracking, crunching or grating noises when they move their knee but such noises do not mean they should stop doing so – quite the contrary: the knee joint relies on movement to stay healthy. Pressure is needed for the cartilage to be supplied with nutrients. Sufficient strain must also be placed on the bones to keep them strong.

If too much strain is placed on the knee, minor injuries can occur in the kneecap area – for example to the ligaments, bones and fine nerves. Why some people experience problems with their knees and others do not despite subjecting them to high loads is unknown. One factor is the way the kneecap moves in the knee joint’s guide channel.

Other possible influences include:

• shortened muscles
• weak thigh and hip muscles
• anatomical misalignments such as different-length legs
• incorrect foot positioning
• misalignments such as knock knees or bow legs
• an enlarged angle between the thigh and the lower leg (Q angle)

The extent to which the factors listed affect the development of anterior knee pain is still unclear. Studies conducted to date have produced partially contradictory results. In many cases, the pain is thought to be caused by a combination of factors.

Excessive strain is the most significant risk factor for patellofemoral pain.

Possible causes of overuse of the knee include:

• running, hiking, climbing stairs and bending the knees
• cycling, especially in the mountains
• increasing the intensity, frequency and/or duration of training too quickly or severely (often in the case of beginners and competitive runners)
• jobs where people squat down a lot while working or lift heavy loads

Anterior knee pain is one of the most common knee problems. It primarily affects young people and those who are physically active, especially runners.

The way that knee pain progresses can vary greatly from one person to the next. About half of those affected only experience pain for a few weeks or months. The other half experience it for several years or recurrently.

The doctor will start by asking about the pain and feeling the knee. The patient will then stand on a step, bend the problematic knee slightly and slowly step down with his/her “good” leg. If this triggers the pain, the diagnosis of “anterior knee pain” is given. Some doctors also use special questionnaires to precisely record the symptoms.

In some cases further investigations are performed to rule out other causes such as osteoarthritis, tendinopathy, knee fractures or a torn meniscus. Imaging techniques such as ultrasound, x-rays or MRI can be used in this regard.

A diagnosis of “anterior knee pain” is given if:

• a patient experiences pain behind or around the kneecap
• the pain occurs when strain is placed on the knee when climbing stairs, running, squatting or similar
• no other causes of the pain can be determined

Rest is recommended in cases of acute knee pain. Athletes should train less or take a complete break to allow the knee to recover. Acute pain can be treated with analgesic and anti-inflammatory gels or creams. These have fewer side effects than painkillers in tablet form, making them a good alternative.

In the long term, it can help to strengthen the thigh and hip muscles as this relieves the strain on the knee joint. People who regularly do appropriate exercises can often alleviate their knee pain and improve their joint function.

People whose feet severely roll inwards (overpronate) when walking may benefit from insoles. This can sometimes temporarily improve the pain. However, there are few indicative studies on the effectiveness of insoles.

It is extremely frustrating if you are completely unable to do activities that you enjoy without pain or can only do them to a limited extent. With knee pain, people often have to accept that even the best doctors are unable to clearly determine the cause of the pain, meaning they cannot offer medical treatment options.

Treatment can take time but it is important to actively participate in the process.

People who have to stop doing their usual sport for longer may be able to temporarily try a different sport that does not cause pain. Examples of suitable sports can include low-intensity cycling, aqua jogging or swimming.

Further information on how to deal with knee pain can be found on the website gesundheitsinformation.de.