Runner’s Knee: When the Knee Suddenly Hurts While You Run

For the past 30 minutes, we’ve been reeling off the miles of our weekly run. The evening sun is shining, the birds are chirping. Everything is just fine, we think – until suddenly the outside of our knee pulls and twinges. Every step feels like someone is hammering dozens of nails into our knee. Instead of being a welcome break from everyday life, our running routine becomes pure torture. Runner’s knee, also known as iliotibial band syndrome (ITBS), is a real horror scenario for many runners.

If we suffer from knee pain while running, most of us can barely make it home hobbling. Often, and this is so deceptive, the pain in the knee joint disappears all by itself when those affected walk slowly. The problem is that runner’s knee doesn’t let go so easily – and can reappear very quickly.

For runner’s knee to actually get better, runners should act as early as possible. But that’s easier said than done – because they don’t know what causes it. That’s why we talked to Prof. Dr. Gert-Peter Brüggemann. The biomechanist and co-founder of True Motion explains the possible causes of runner’s knee – and the role running shoes play in this.

The problem: when running, this back-and-forth movement is unavoidable. At the same time, it is exactly what can ultimately lead to the pulling pain – a classic inflammation. This always occurs when the fascia is injured in the long term during the movements – like a rope that scrapes against a ledge for a long time.

The result is a stabbing pain on the outside of the knee at the tractus iliotibialis – runner’s knee. However, since the pain often occurs first and usually only during movement, athletes tend to forget that they have knee problems. The point in time when the knee joint actually starts to hurt is different for every runner. Some feel the irritated fascia after just a few meters – others, on the other hand, can still do some training without problems.

Only specialists should diagnose a runner’s knee. If runners describe their symptoms, orthopedists can usually diagnose ITBS quickly. In the process, doctors rule out other injuries to the knee that cause similar symptoms. Such conditions include:

• cartilage damage in the knee joint,

• irritation or injury of the outer meniscus,

• osteoarthritis of the outer part of the knee joint,

• osteoarthritis of the hip,

• a torn muscle,

• a fatigue fracture.

In order to be able to distinguish runner’s knee from the above-mentioned injuries, the specialists ask the runners specific questions before treatment. To be absolutely sure, the doctor also palpates the affected area and moves the knee. If patients complain of pain, the diagnosis is often clear – ITBS. Specialists can then begin targeted therapy and treatment of the iliotibial tract.

The biomechanical interaction of our body is crucial for the development of runner’s knee. Actually, all joints of our body should interact optimally with each other. But this perfect world is often disturbed. As a result, if even one link in the chain changes slightly, this has an immediate effect on the entire body and its course of movement. This is comparable to a game of dominoes.

• Malposition of the leg axis: People who suffer from a malpositioned leg are susceptible to runner’s knee. Especially in the so-called bow-leg position (also: genu varum), the tension of the fasciae on the outside of the knee is increased. Similar to the misalignment, the natural biomechanics of the leg axis are disturbed at many points. As a result, the knee is more susceptible to the typical complaints associated with running.
  
  

• Inappropriate running surface: A surface that is too hard, such as asphalt or sloping roads, places particularly intensive stress on the leg muscles. The force exerted on the joints is not cushioned and unforgiving. This further aggravates already faulty biomechanics.
  
  

• Unsuitable running shoes: As already mentioned, looking at the shoes is particularly important. Unsuitable running shoes, such as rigid, non-flexible running shoes with overly hard cushioning and running shoes with angular outsoles, force the feet into an unnatural posture – creating anatomical imbalances. This significantly increases the catapult effect – or leads to the body not being able to absorb it in the first place. As a result, feet, knees, and hips lose their natural range of motion. This results in poor posture during running. If runners have knee pain during sports, it can therefore make sense to change shoes.

Since runner’s knee is the result of overuse, the first thing that helps with acute knee pain while running is taking a break from running. But this alone is sometimes not enough. Although the pain often subsides when we stop putting weight on our knee, there are exceptions. Then runner’s knee hurts acutely, even at rest.

A suitable therapy in these cases is to put a cold pack on the aching knee and rub it with anti-inflammatory ointments such as Voltaren. Both help reduce the symptoms of inflammation in the knee. The swelling on the outside of the knee goes down.

Since it is ultimately a hardened and tight fascia that triggers the pain of runner’s knee, stretching and fascia exercises are particularly helpful. Physical therapists show us which exercises work best. They also help us to perform them correctly.

Stretching exercises are an effective helper when it comes to lowering tension on muscles, tendons, and fascia. The tractus iliotibialis – the fascia that is tense in runner’s knee – is connected to three muscles. All three of these muscles are located in the gluteus and on the outside of the leg. Stretching exercises help apply traction to the fascia. This pulls the muscles that are attached to the fascia.

In addition to stretching exercises, so-called fascia training also helps as an initial therapy to loosen the tractus iliotibialis again. Fascia rollers are suitable for this purpose. The targeted pressure of the fascia roller on the affected area can loosen the tension in the fascia. This is important because, after all, the overstretched fascia is the trigger of runner’s knee. Fascia training also helps restore fluid and nutrients to the tissue. This not only promotes healing, but also has a preventive effect against the development of ITBS.

As a general rule, it is a good idea to stretch before exercising and warm up the fascia before running. This helps prepare the fascia for the upcoming load and can prevent tightness.

In order to defeat runner’s knee in the long term or to ensure that it doesn’t occur in the first place, those affected need to take a closer look at the causes. Whether it’s just an unsuitable surface or a trained malposition – the triggers all have one thing in common: the right running shoes have a significant influence on the running experience.

Shoes are the link between the ground and the body. From the ground, the shoes transmit all forces to the legs. If the transmission of forces is disturbed, this is where unhealthy leverage forces originate from a biomechanical point of view – the catapult effect already described above. Both worn and improperly fitting running shoes can intensify this effect or even trigger it in the first place.

In order for the body to better fight the bending forces, it also helps to train the abductors, Prof. Dr. Brüggemann explains. The abductors are the muscles on the outside of the leg. They lift the leg laterally – and are thus the counterpart of the bending force, so to speak.

In concrete terms, this means that the abductors always counteract the bending force when the leg wants to bend outward. Accordingly, it is important to train them. However, this does not combat the cause, “but only the already existing pain and discomfort,” explains biomechanist Brüggemann.

But this is not a general ban on sports. Because even during acute runner’s knee, there are some gentle alternatives; sports like swimming or cycling put less body weight on the legs. They are therefore ideal alternatives to running.

If we have found and eliminated the cause, we can restart running after two pain-free weeks. However, we should not overdo it at the beginning. Instead, we should go about it slowly and carefully – and start training with short running sessions. If discomfort reappears, it is important to stop and take another break from running.

However, if we remain pain-free, we can gradually increase the load. As a rule of thumb, we can increase our running distance by one kilometer every one to two weeks.