How To Treat Knee Joint Injuries – Knee Joint Clinical Examination

We were all taught knee assessment at university. It’s the first joint you cover. It seems like a simple open and shut case with some easy tests.

However, as is always the case, when you have an athlete in front of you in the real world it can be a little bit different. It’s never as black and white as we are taught.

Today I’ll share with you the simple step-by-step approach I have performed with thousands of professional athletes…

The key thing we need to understand about the knee joint is that it will only ever be as successful as the hamstring and gastroc will allow it to be. When the foot hits the floor it is critical that the hamstring and the quads co-contract to tolerate the ground reaction forces.

What we usually see in patients that have knee pain is that as they start to push off the hamstring and gastroc don’t delay knee extension. If that knee snaps back all of the forces are coming down to the knee joint. If the quads are doing all the work we see the vastus lateralis act as a hip extensor.

What we want with the knee joint is as the foot hits the floor and the ground reaction forces take effect, the gastroc and the distal hamstring delay the extension which allows the glute max to actively extend.

In the Go-To physio mentorship we always talk about the 80/20 rule.

It’s simple, we spend 80% of our time treating the true cause of the problem and 20% of our time getting the symptoms to settle down. This means that 80% of our time will be focused on getting the hamstring, gastroc and glute doing the job and 20% on getting the symptoms at the knee joint to calm.

Before you can treat the true cause you need to find it so today we can focus on making sure there is no ligament damage or significant trauma that may need more intervention by having clarity on the knee joint objective assessment.

Sweep test

The first thing I usually do is a sweep test. I’ll get that VMO and I’ll pull it, then come through with the vastus lateralis and push down along the outside of the leg.

What I am looking for is any pocket of fluid entering the groove above the knee. If there was then I would think there could be something inside the knee joint itself contributing to this effusion.

If you do see a little effusion, don’t panic, many professional athletes have recurring issues. It is useful to ask them directly if this is normal.

Hyperextension test

What I want to do here is stress the anterior joint line including the meniscus. I close down the anterior joint line, if there is anything that is unhappy there then it will cause a pinch or sensitivity.

I also want to see if it has a nice end feel or is it blocked. Many athletes will be blocked into extension which means you can ask yourself, what is stopping that?

If there isn’t a full extension then you can work around the knee capsule itself, or the semimembranosus tendinosis. If you can decrease the protective tone you will usually find you can restore extension quite quickly.

Just because the knee extension gives a bit of a pinch does not necessarily mean there is an issue with cartilage and it will need surgery to rectify.

When you’re doing your passive knee flexion you want a good amount of over pressure. This overpressure is going to challenge the posterior compartments of the cartilage as the femur and the tibia close down into it.

If there is any pinch or sensation there then you might pick it up with this over pressure. If there is a pinch deep in the knee then it could mean that there is some protective tone present. Don’t forget if you can influence the anterior knee capsule then you can decrease protective tone.

Again, just because we get that pinch you don’t need to jump to conclusions that your patient needs a clean out or anything like that.

To recap; if there is a pinch with knee flexion, but there’s no effusion, I’d be a little bit more happy. If there is a decent knee effusion with a positive sweep test and your patient is getting a pinch with hyperextension then I would be thinking the cartilage could be causing these issues.

The biggest mistake I see when therapists do this test is not putting enough force into what they’re doing. I want to make sure I am genuinely stressing the joint line. When you push, you want to push through the joint line. Your elbow should be in line with the shin and to give the joint a good stress.

I’d rather be aggressive with my test here and elicit the symptoms than be gentle and miss something. You need to be challenging the joint line.

If your patient does feel laxed then ask them if they have done this before. A lot of MCLs will still have a lot of laxity especially in professional athletes.

Your history will give you a big clue with this. If someone has fallen on the knee then I would be highly suspicious that the PCL could be involved. All you have to do is push the tibia and fibula backwards onto the femur and see if your patient experiences a pinch.

For the ACL you can do the test when you do the anterior draw. The important thing here is to take up the slack with the hamstring tendon in the gastroc. Sink through and compress the tissues and pull. If you try and pull and the tendons aren’t compressed then you’ll get a reflexive reaction as the tendon lengthens.

Remember, if your athlete has come straight from the training ground and there is some kind of protective tone there it can feel quite loose so do not panic.

As with the last ACL test, come through the posterior and take all of the soft tissue then apply the force. Here you can get a good end feel.

If this is an acute injury and it has just happened you may struggle to find an end feel. There could be some inhibition and looseness. If the athlete comes straight off the field and there is a decent effusion then there could be some ligament damage. If there is no effusion and things just feel a little loose, allow for 24 hours, let it settle down and come back to it.

So we have our flow of tests;

• Check effusion
• Hyperextension
• Flexion
• MCL/LCL
• ACL
• PCL
• Lachman

Of course, there are plenty of other tests such as the posterior lateral corner ‘dial test’ etc. After this you could go into more advanced tests but these will catch the majority of issues that you will face.

For me the knee effusion plays a big part in how much respect I pay to these tests. If there is one then I would be paying more attention to my overpressure tests. If there is no effusion and there is pain with overpressure then very often this can be changed and you can restore movement quite quickly.

The big thing to understand is that you can change these tests quite quickly using some hands-on work, decreasing protective tone around the capsule, the MCL and the LCL. You can restore the hyperextension and the flexion very quickly.

Remember just because these tests are positive does not mean they need to go straight to the surgeon. Let them settle down, control the pain, settle the effusion and very often the symptoms will calm.

Be more aggressive… You would rather elicit something than miss something and send an athlete back to the training ground only for you to have missed something. The consequences can be bad.

If you want to learn more about the Go-To therapist approach or more skills you can implement in your practice today, click here.