The Collateral Ligaments of The Knee

Hello and welcome back to the ThreeSpires Physiotherapy blog where we take a look at all things physiotherapy and health related. In this blog I thought we could carry on looking at the knee but this time move onto two of the important ligaments of the knee which commonly get injured and cause pain: the medial collateral ligament (MCL) and the lateral collateral ligament (LCL). I had been considering covering the cruciate ligaments of the knee in this same blog but on reflection they are deserving of their own blog post!

When discussing structures such as the ligaments in the knee it is important to have a good understanding of what the structure is, the anatomy and where it can be found before considering specific injuries and rehab. So I think firstly we should now have a look at what the ligaments in the knee actually are:

The Collateral Ligaments of the knee

The collateral ligaments are generally fairly easy to visualise as these are on the outside part of the knee and for most people they will be easy to find (or at least know where they are).

There are two collateral ligaments at the knee joint – collateral means being on the side of the joint: the medial collateral ligament (MCL) and the lateral collateral ligament (LCL). Both of these knee ligaments are on the side of the knee and provide stability and restrict side to side movements. The MCL is on the inside part of the knee – so if you look at your own left knee the MCL will be on the side of your knee closest to your right knee. The LCL is on the opposite side of the knee and jointly these ligaments give the knee a large amount of lateral (side to side) stability. The MCL is by far the most commonly injured partly because of its attachments to the medial meniscus and mostly because if you have a blow to the knee it is likely to come from the outside and push the knee inwards (as in a tackle in football or rugby). Some form of trauma i.e. a fall, a twist of the knee or a hard tackle is the most common reason for a collateral ligament strain in a sporting environment but it can sometimes be caused by biomechanical weaknesses which we will look into in a bit more detail later. 

What is the role of the Collateral Ligaments?

The collateral ligaments of the knee the medial collateral ligament (MCL) and lateral collateral ligament of the knee are on both sides of the knee with the medial collateral ligament (MCL) attaching the femur to the tibia and the lateral collateral ligament (LCL) doing the same. As such they are there to provide general stability to the knee joint and help especially with stabilising in terms of side to side forces through the knee. It is worth reminding ourselves that ligaments are passive structures and do not have any contractile properties, by this I mean that they are not an extension of a muscle in the same way as a tendon is. During any movement of the knee with a lateral force component such as turning or twisting the collateral ligaments will come into play and provide passive stability at the knee joint.

What are the Symptoms of a Collateral Ligament Tear?

In general, the symptoms of a collateral ligament or lesion are fairly easy to define and unlike other knee conditions such as patella-femoral pain will in general be felt very sharply on the outside and side parts of the knee and if severe enough will be accompanied by swelling:

• Pain: this is very likely to be sharp and initially at least very severe. Often the patient will describe a clear mechanism of injury (although this is less likely in older patients). Pain will also be described as being located over the area of one of the collateral ligaments and will often present as a very sharp jab in that area.
• Swelling: certainly in the early days there may be quite significant swelling, especially if the patient can remember a particular incident that they think started it. The swelling though could be quite general across the whole knee and not simply located at the site of the collateral ligament.

An important point to note is that these could be the symptoms of quite a few other conditions and not just a collateral ligament of the knee tear and it is important that you get it confirmed by a professional (such as a physiotherapist) that you actually do have a collateral ligament tear.

What Causes Collateral Ligament Tears or Injuries?

In general but not always there is at least an aspect of trauma or “an event” that the patient can remember when they think that they hurt their knee. Generally, it will be quite a clearly defined event such as playing football and they have an impact or twist and hurt their knee. However, sometimes the initial injury can feel very minor such as a minor grumble on the side of the knee whilst running but then this significantly worsens over the next few runs until the pain is very severe. Below are some common causes or situations in which collateral ligament injuries occur:

1. A twisting or sideways force at the knee: This can happen in quite minor situations such as stepping off a kerb and losing balance or could be in a game of football and the player twists and feels an immediate pain in either side of the knee.
2. Trauma: here there is again a very clear mechanism of injury and it will usually involve at least some form of sideways impact on the knee causing the ligament to come under load suddenly and be injured. For example this could involve a player receiving a sideways tackle and impact at the knee in a game of football and feeling an immediate pain.
3. Overload: this is a much more difficult situation for both the patient and the physio to decide upon. Here the patient will usually describe a very minor issue at the side of the knee that has progressively worsened over a few months and is now very sharp and painful. Generally, there has simply been an initial injury to the collateral ligament that the patient has not fully been aware of and they have after this continued to keep using the knee and not rested it. Over a few weeks or months the ligament has slowly become more and more irritable.

I think the main point to note from the above is that commonly the patient will be able to at least describe clearly when the pain started and mostly there will have been some form of clear mechanism of injury.

Who is at Risk of a Collateral Ligament Injury?

Well, pretty much anyone with a knee can injure or tear their collateral ligaments but there are some factors that make injury more likely.

• Anyone involved in a sport or activity that involves jumping, landing, turning and twisting at speed. Sports such as football, netball, basketball, hockey and rugby all involve this kind of motion and have a risk of collateral ligament strains as a result.
• Weight: people with a high BMI can often overload their collateral knee ligaments.
• Anyone starting a new sport involving running, sprinting or twisting etc. In the early days of beginning a new sport your knee ligaments are likely to be exposed to stresses that they are not accustomed to and can get injured as a result.

How is a Collateral Ligament Injury Diagnosed?

Initially, an injury to either the lateral or medial collateral ligament of the knee will be diagnosed through a combination of symptoms and a physical assessment by a physiotherapist. At this point a variety of factors such as age, sporting background, severity of symptoms, length of symptoms and the patient’s goals will determine whether or not an MRI is required to confirm the diagnosis. Sometimes patients will initially go to their GP with knee pain and then be referred on to a physiotherapist. The physio at this point will take a full history, do a physical assessment and based on the combination of these factors make a diagnosis of a knee collateral ligament injury. As with most sporting injuries It is best to get an early diagnosis of a collateral ligament injury as this allows the best management and treatment plan to be devised and for you to get back to your activity as soon as possible. Delaying a diagnosis and letting things worsen will only lengthen the rehab process needed for your collateral ligament.

Treatment for Collateral Ligament Injuries

In general, most collateral ligament injuries will respond to a slow return to activity and exercises designed to strengthen the ligament. Occasionally there is a need for more aggressive options such as surgery but this is not common. Below I have tried to cover the most usual options for helping with collateral ligament strains.

1. Early Assessment & Diagnosis: I know this sounds like common sense and a bit of a cop out but in reality this is the most important thing you can initially do to help the collateral ligament in your knee recover. You need to know exactly what the issue is and get some advice on what to do next. By having an early assessment and getting a clear diagnosis you can be confident about what you are dealing with and then choose the best treatment options. It is also important to note that the medial collateral ligament at the knee is attached to the medial meniscus and this can be injured at the same time. For more information about the meniscus and injuries to it click here.
2. Rest: yes, I can hear many people already saying but rest is not a treatment. Well, I beg to differ, in the early days (certainly the first week) the best thing that you can do is give yoru knee and the collateral ligaments a rest and allow the natural healing processes of your body some time to take place. Now, this is unlikely to mean that you have to be off your feet completely for the whole week more it means that you need to stop any sport and try to do less on your feet for a bit until the initial pain has subsided.
3. Exercise & Strengthening: For the large proportion of collateral ligament strains physiotherapy, exercise and strengthening will be the best approach. The most important factor with exercises is that they need to be progressive and start at a low base in order to allow you to slowly increase their difficulty over time and increase the strength of your collateral ligament.
4. Brace: sometimes (especially in the early recovery period) a brace can be useful to stabilise the knee joint and give the patient some security and allow them to weight-bear and thus improve the healing of the ligament.
5. Surgery: in most cases collateral ligament injuries are unlikely to require surgery, however sometimes the injury to the ligament has been very severe and the ligament has been disrupted and torn too much for a normal healing process to take place. In these cases surgery will be needed but as mentioned for most injuries to the collateral ligaments of the knee surgery will not be needed.

Okay, I think we have looked at enough possible options here, the main thing that I have wanted to convey is that collateral ligament injuries in general respond very well to physiotherapy, early assessment and a slow and progressive increase in exercise and strengthening. Only rarely will a surgical opinion be needed for a collateral ligament injury of the knee.

How Can ThreeSpires Physiotherapy Help with My Collateral Ligament Injury?

Physiotherapy is extremely helpful if you have injured either your medial collateral ligament (MCL) or lateral collateral ligament (LCL) of the knee and one of our physiotherapists who is experienced with managing and treating collateral ligament injuries will be able to help. We can help in a  number of ways:

1. Assessment & Diagnosis of a Collateral Ligament Injury: this as mentioned earlier is a vital part of managing your collateral ligament injury and the sooner you have an assessment the sooner you will know what you are dealing with. Our physiotherapists will be able to comprehensively assess your knee, make a diagnosis and also identify underlying biomechanical causes of your collateral ligament strain such as core weakness.
2. Management Plan: once a diagnosis of either an injury to the medal collateral ligament (MCL) or lateral collateral ligament (LCL) at the knee has been made it is vital that you get a clear and comprehensive plan to optimise your recovery. Your physiotherapist will be able to identify the best strategy for helping with your collateral ligament injury and will be able to advise on the best exercises, the optimal recovery and management plan and how to get back to your chosen activity.
3. Exercises for Collateral Ligament Injuries: your physiotherapist will be able to determine which are the most appropriate exercises to help strengthen your knee, help the ligament recover and also strengthen surrounding structures and areas of the body.
4. Treatment for Collateral Ligament Injuries: In conjunction with load management and exercises your physio will be able to use soft tissue and hands on techniques to treat any areas of your legs that have become overloaded and tight.
5. Supplementary Exercises for Collateral Ligament Injuries: as part of your assessment for a collateral ligament injury your physiotherapist will also look at strength and biomechanics in your legs and see if there are any imbalances or weaknesses that might be contributing towards your collateral ligament getting overloaded. As such they will likely prescribe a series of other exercises designed to improve strength and control and help you reduce the likelihood of further injuries.

Okay, I hope that you have found this article about collateral ligament injuries helpful. Should you or anyone you know have a collateral ligament injury or suspect that you have one please get in touch and one of our physios would be happy to help.