Off the top of my head I can think of at least 10 different reasons for having knee pain from referred back and hip pain to osteoarthritis and ligament injuries…
But I am going to focus this blog all things related to the cartilage
First of all the terms – cartilage and meniscus are the same thing
The meniscus is a very important part of the function of the knee joint.
It’s ‘job’ is to:
• Prevent ‘wear and tear’ of the articular cartilage (see diagram 3 below) covering the bony surfaces of the femur (thigh) and tibia (shin)
• They help spread the load evenly across the whole of the joint and help with absorbing shock
• Help with the stability of the knee
• Keep the joint healthy, well lubricated and provide nutrients to the joint surfaces
• Assist with proprioception (an awareness of where your joint is in space) which is an important part of balance
Diagram 3: The Articular Cartilage (white) covers the body surfaces of the thigh & shin
The Medial (inside part of your knee joint) meniscus is wider and slightly longer than the Lateral (outside part of your knee joint) meniscus
The meniscus has a high water content (about 70% of it is water) and a limited blood supply only 10 -30 % of the outer edge of the medial meniscus (inside your knee joint) and 10-25% of the lateral meniscus (outside part of the knee joint).
This means that any injuries to the cartilage can take time to heal and will benefit greatly from exercises and treatment that work on getting full range of movement, improve our balance and maximise the timing and muscle activity of the hip, knee and foot.
Different types of tears
Causes of Meniscal Tears
Injuries can happen at any age but in younger people, because the meniscus is stronger and better able to deal with twisting forces tears tend happen as a result of trauma – so a foot stuck in the ground as you turn.
As we get older the meniscus naturally loses some of it’s elasticity and thins so cannot ‘bounce’ back so easily – so getting up from a simple squat or crouching position can cause a degenerative tear.
In my own clinic I have seen many traumatic tears from football! (this may be why men tend to be affected more 4:1 ☺) or playing tennis but as we get older tears can (and do!) happen just stepping down slightly awkwardly down a step and even climbing over a stile!
Signs and Symptoms of a Torn Meniscus
In an acute traumatic tear you can often feel a sudden sharp pain, possibly a ‘clunking’ sensation. Depending upon how it happens and your age you may be unable to continue to put weight on your knee as the Anterior Cruciate Ligament (ACL) is often involved. The onset of swelling for the meniscus is usually a little delayed later that evening or the next morning is common.
In the more degenerative tears pain is often over the inside of the knee (along the line of the joint where the femur meets the tibia) usually horizontally with some pain radiating downwards – this is because the medial meniscus is slightly more prone to injury. You can also feel pain towards the back of the knee inside and if you injure the lateral meniscus you will tend to feel pain over the outer edge of your knee joint.
Swelling is more of a sensation of feeling that your knee is tight, stiff or swollen – even if you can’t actually see an obvious swelling when comparing it to the other knee. The knee can also feel unstable, like you can’t trust it fully.
One of the most common problems is not being able to either fully straighten of bend your knee – or both! You may have a clicking or locking sensation that is usually painful or can make you feel a bit ‘yuck’!
Pain is common at night too – not wanting the inside of your knee to feel unsupported
Treatment / Management of Meniscal Injuries
Conservative (non-surgical) management:
• Rest & do nothing! (not something I would recommend )
• Relative rest – so keep active but avoid twisting, jumping type activities for 4-6 weeks (depending upon severity of symptoms / tear)
• Active treatment – physio, exercises (my definite preference! ☺)
• Arthroscopy (removing damaged part of meniscus & washing joint out) – This is being done less now due to anaesthetic risk, scar tissue as a result of surgery and removing part of your meniscus slightly increases the risk of you developing Osteoarthritis in the long-term. Surgeons would generally expect you to have tried the conservative treatment approach first.
The first thing I would say about this is that as physios we can make sure that it is your meniscus that has been injured! Simply because as I said earlier there can be other causes – such as Osteoarthritis which can have a very similar signs and symptoms.
Restoring the knee range of movement. Being able to fully straighten your knee allows the meniscus and the rest of the knee structures to receive it’s full nutrients. It reduces the risk of any further injury the load and weight is spread evenly over the whole of the joint.
It also means your muscles work better to support your knee joint and reduces the load on the other knee structures – such as your knee cap! Ultimately, it will ease your pain as it will help reduce the swelling.
Any exercises that help strengthen the hip can reduce the stress on the knee, especially the structures on the inside.
This is a good exercise to help with pain going down stairs:
This can help improve your knee range of movement
Getting a good night’s sleep…
Whilst I wouldn’t suggest sleeping like this in the long-term placing a pillow between your knees if you are laid on your side can help ease knee pain in the first 1-3 weeks.
Beyond the initial 4-6 weeks & returning to sport
As a physio who is passionate about movement and not giving up something you enjoy it might be worth seeing your physio to just have a look at how well you manage the forces over your knee – by this I mean how well you jump and land, change direction…You may benefit from some more dynamic weight-bearing exercises – if nothing else it will help you feel more confident in your knee!
Please note this Blog is not meant as a substitute for a thorough physio assessment! If you have any concerns or you try the exercises and your knee pain worsens please seek a professional advice.
Exercise Images From Physio Tools (www.physiotools.com) & Joanne Elphinston – ‘Stability Sport & Performance Movement: Practical Biomechanics and Systematic Training for Movement Efficiency and Injury Prevention’ 2013