Knee pain is an extremely common area for pain to develop for a variety of reasons. The more commonly seen acute ligamentous injuries that are seen on television are well known by how bad they can look. Less well known are how biomechanics (meaning how we move) can influence the position of the knee cap, and how overloading tendons around the knee can cause them to become painful tendinopathies. It is fortunate that in the vast majority of cases knee pain responds well to conservative physiotherapy.
Types of Knee Pain
- Acute ligament injury
- Patellofemoral joint pain syndrome (knee tracking problems)
- Tendinopathy affecting one of the tendons around the knee
- Fat pad syndrome
In children and adolescents knee pain can be diagnosed as
- Osgood Schlatter's
- Sinding Larsen Johansson Syndrome
Causes of Knee Pain and Things to Look for
Acute Knee Injuries - this type of problem is experienced in contact and non-contact sports. It can indeed be caused through heavy contact forcing joints into positions that they normally would not go, however quick movements while fatigued and/or without adequate support around the joint can cause joints to move into positions they normally wouldn't.
Patellofemoral Joint Pain Syndrome - occurs when the kneecap (patella) is not sitting well in it's groove. When the patella moves either too much in or out it causes too much friction to occur at the back of the knee. This is why people who experience this pain feel the discomfort behind the patella.
Tendinopathy - is categorised as an overload/repetitive stress injury that affects one or multiple tendons in the body. In this instance the most common areas to have discomfort are over the patella tendon or hamstrings. By overloading these tendons it causes the structure of them to change in such a way that they are less capable at handling pressure resulting in pain and/or stiffness over the affected tendon. These areas can be overloaded through many ways such as changes to,
- Muscle balance around the knee (quadricep versus hamstring strength/length)
- Recovery schedule
- Training volume/days
- Training/game surface
Fat Pad Syndrome/Impingement - is less commonly known but quite painful when it occurs. Located underneath the patella tendon is a structure called the fat pad. In certain circumstances it can be rubbed causes it to thicken which results in greater friction. As it is highly innervated by pain receptors resulting in severe pain located underneath the patella tendon with moderate swelling present. The cause of the initial rubbing of the fat pad can include any of the following;
- Standing in excessive knee hyperextension - locking the knees to far backwards
- Standing in anterior pelvic tilt. When people stand with a very arched lower back it forces the knees backwards
- Excessive tightening of the rectus femoris (part of the quadricep)
Treatment for Knee Pain
There is no one size fits all approach with treating knee pain as the strategies that are used to relieve it depend on the diagnosis. It is the role your physiotherapist to conduct a thorough examination to correctly identify the structures that are affected and the mechanism of injury. In accurately doing so it is straight forward in fixing the problem.
Acute Knee Injuries - initial rest is usually warranted with a gradual reintroduction to pressure involving the affected ligament(s). Initially hands on physiotherapy is used to restore normal range of movement, minimise swelling and scar tissue formation. Exercise rehabilitation starts when pain allows which involves strength and proprioceptive (balance) training, as well a stretching program. Rehabilitation then becomes more sport specific depending on the needs of the client.
Patellofemoral Joint Pain Syndrome - identifying why the patella is not sitting in its groove is critical. This can involve one or more of the following
- Pronated (flat) feet
- Poor lateral hip strength/activation allowing the knee to drift inwards with movement
- Muscle imbalance around the knee. When the outside quadricep muscles overpower the inside quadricep it forces the patella outwards
- Too much or too little movement of the patella
- Excessive tightening of the quadriceps
By identifying the mechanism it is then corrected and over a course of weeks the pain is relieved.
Tendinopathy - similar to patellofemoral joint pain syndrome it is critical that you are your physiotherapist identify how the tendons have been overloaded. In doing so it is addressed and an exercise rehabilitation program is implemented. As mentioned previously tendons that are affected with this condition do not tolerate load/pressure as well as they normally do resulting in pain. The exercise rehabilitation program aims to reverse these changes in tendon structure in order to improve their capacity to load/pressure.
Fat Pad Syndrome/Impingement - in order for this condition to be treated the mechanism of increased friction of the fat pad needs to be identified and corrected. At the same time a course of anti inflammatories and taping is often used to provide immediate pain relief and position the knee in such a way tthat it prevents any further friction of the fat pad
Hopefully this article has helped some of you indentify what could potentially be causing your knee pain and what to expect from treatment. However, it is notoriously difficult to self-diagnose the cause of knee pain. Often you will need another set of trained eyes to identify what is going wrong (and right!), and how to fix it.