A lateral meniscus tear doesn’t happen as easily as a medial one, and they tend to heal better when left alone. However, a lateral meniscus tear can take longer to heal after surgery. This article explains the symptoms of a lateral meniscus tear as well as the treatment options, the correct rehab exercise approach, expected recovery times, and why surgery should be the last resort. Remember, if you need more help with an injury, you're welcome to consult one of our physios online via video call.
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Anatomy
You have two menisci in your knee – one lateral and one medial. The lateral meniscus is on the outside of the knee and the medial on the inside.
They are C-shaped discs made of cartilage, and their outer edges are thicker than the inner edges. This forms a concave surface that helps the femur (thigh bone) to sit better on top of the tibia (shin bone), contributing to the stability of your knee. The menisci also function as shock absorbers and help to distribute load more evenly through the knee joint.
The medial meniscus is more securely attached to the ligaments and other structures in the knee than the lateral one and doesn’t move much when your knee moves. The lateral meniscus is more mobile and moves with the outer joint surface of the femur as you bend and straighten your knee; this is partly why it doesn’t get injured as often as the medial meniscus.
The outer 25% to 30% of the menisci gets a blood supply. The inner portion does not have a blood supply; it depends on the synovial fluid in the joint to supply it with nutrients and oxygen and to remove carbondioxide and other by-products. This is why movement is important for the meniscus, because the change in pressure funnels the synovial fluid to and from it.
How does a lateral meniscus tear happen?
Meniscus tears are most often caused by movements that involve a forceful twisting or extreme bending of the knee. These actions can also injure other parts of the knee, and a lateral meniscus tear often occurs in combination with an anterior cruciate ligament (ACL) tear.
Lateral meniscus tear symptoms
The pain caused by a lateral meniscus tear is located over the outer edge of the knee, along the joint line. Depending on what part of the lateral meniscus is injured, it can be over the front part of the outer edge, directly on the outside, or more towards the back of the knee.
The swelling can vary – from a bit of puffiness to having an extremely swollen knee. Most likely you will not be able to bend or straighten your knee fully, but this should improve within a few weeks. A physio will be able to tell whether your knee movement is recovering at a normal pace.
You may experience a feeling of instability, clicking or “popping”, or that your knee wants to lock when you move. Walking can either be very uncomfortable, or it can be mostly fine until you try to walk up or down an incline or stairs. Walking on uneven terrain can often cause pain.
Does a lateral meniscus tear require surgery?
Very likely not. There is evidence that stable lateral meniscus tears heal by themselves in the vast majority of cases, and they tend to heal better than medial meniscus tears.
Studies that followed the long-term progress of patients have shown that the recovery rates and results one year after the injury are very similar for people who have had surgery and those who underwent a conservative treatment plan.
Surgery does not guarantee good results and may increase your chance of developing osteoarthritis in the knee, so it is currently advised that conservative treatment (consisting of relative rest and exercise – see below) should be the first choice for lateral meniscus tears.
However, not all meniscus tears react equally well to conservative treatment, and if it is torn in a way that blocks your movement (e.g. a bucket handle tear), it may require surgery. Your doctor will consider the following factors when deciding whether you need surgery:
The type of tear (stable vs. unstable, or blocking movement)
How it affects your function – are there signs of improvement, or does it continue to severely affect your function several months later?
How it reacts to conservative treatment – i.e. rehab exercises for at least 6 months, although full recovery can take up to 12 months.
If surgery is required, meniscus repair surgery is the first option, but this is only feasible if the tear is in an area with good blood supply and if the meniscus is not too damaged.
The next option is a partial meniscectomy, where they trim the injured part of the meniscus away. Meniscectomies often lead to poorer outcomes, including ongoing pain and swelling. They are also associated with an increased risk of early osteoarthritis. Lateral meniscus tears do worse after a meniscectomy than medial meniscus tears because of how the load of your weight is distributed in your knee.
As an aside: Clinicians used to think that ACL tears should be repaired surgically as soon as possible to prevent further damage to the meniscus. However, there is new evidence that delaying or avoiding ACL surgery and following conservative treatment instead do not lead to further tearing of the meniscus.
Lateral meniscus tear treatment – conservative approach
The knee works as a unit, so the conservative treatment for meniscus tears, including what exercises you do, is exactly the same for lateral and medial meniscus tears. There are three phases:
Phase 1: Treatments that decrease pain and increase movement
This is for the very early stage of your rehab, when your knee is still very painful, swollen, and stiff. The main aim is to help your injury to settle down. Treatments that may be useful include:
Icing your knee intermittently to reduce swelling and pain. Here’s more information on how to apply ice to an injury and what to avoid.
Gentle movements and exercises to reduce pain and swelling and to start activating the muscles that support your knee. The movement also improves the supply of the much-needed synovial fluid to the injured meniscus. You can find examples of exercises used during this early stage of meniscus tear treatment here.
Reducing the load on your injured knee, e.g. using a walking stick or crutches, or simply reducing the time you spend on your feet. For instance, don’t try to clean the house in one go. Rather break the task up in smaller parts and rest in between, or spread them out over several days.
Pain medication can be useful if your pain is severe or your knee is badly swollen. There is some evidence that nonsteroidal anti-inflammatory medication (like ibuprofen) may not be that good for healing, so consider exploring other options with your doctor. However, if you use it for only a few days to reduce severe swelling, the benefits may outweigh the risks; it’s long-term use that may cause problems.
Phase 2: Gradually restore your full strength and control
The most important treatment during this phase is the right combination of relative rest and rehab exercises.
Relative rest
The aim with relative rest is to stay as active as possible without increasing the pain and swelling during the activity or in the 24 hours afterwards.
Complete rest isn’t useful at this stage because, while it calms your pain down, it can actually make you lose even more strength and control. Relative rest helps you to maintain the strength, control, and endurance you currently have, and it also allows you to gradually improve these as you recover.
For instance, if you go for a walk and it only feels mildly uncomfortable, but there’s no increase in pain or swelling later on, then it was fine to do that walk. On the other hand, if everything feels fine during the walk, but that evening or the next day your knee is significantly more painful and swollen, it was likely a bit too much.
Use this approach for all your activities, including your rehab exercises.
Rehab exercises
These exercises will teach you good movement patterns and control.
Initially, they involve low-load and very stable movements, e.g. a double-leg squat within a limited range of movement. It is important not to rush the rehab; for instance, you can make your injury worse if you try and squat too deeply at the start.
However, as your injury heals, the exercises should gradually become more intense and complex to eventually restore the full strength and control you need for the types of activity or the sport you want to be doing.
Here is our full guide for meniscus tear rehab, including what exercises to do (with demo pics and video clips).
Phase 3: Easing back into sport
Once you’ve completed your rehab exercise programme, your meniscus won’t be ready yet to cope with a complete session of top-intensity match play or running.
This is why it is important to ease back into your sport with a run-walk programme or half-effort training sessions to start with. If you resume your sport too soon or too intensely, you risk reinjuring your knee.
A physio can help to assess whether you’re ready by setting you specific movement tests or exercise targets.
Lateral meniscus tear recovery time
The recovery time for meniscus tears depends on the severity of the tear, what part of the meniscus is torn, your age, and whether surgery is needed. It can be anything from 8 to 12 weeks for simple tears in younger adults but up to 6 months to a year in other cases.
How we can help
Need more help with your injury? You’re welcome to consult one of the team at SIP online via video call for an assessment of your injury and a tailored treatment plan.
We're all UK Chartered Physiotherapists with Master’s Degrees related to Sports & Exercise Medicine. But at Sports Injury Physio we don't just value qualifications; all of us also have a wealth of experience working with athletes across a broad variety of sports, ranging from recreationally active people to professional athletes. You can meet the team here.
About the Author
Maryke Louw is a chartered physiotherapist with more than 15 years' experience and a Master’s Degree in Sports Injury Management. Follow her on LinkedIn and ResearchGate.
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