Knee injuries

Knee injuries in active people

Torn cartilage / meniscus tear

A torn cartilage (us doctors call this a torn meniscus) is one of the most common things that I see. The meniscus (plural: menisci) is a little rubbery crescent-shaped shock absorber cartilage which sits between the shin bone and thigh bone. There is one on the inside of the knee which we call medial, and one on the outside of the knee which we call lateral. It is more common that the medial meniscus is torn.

A bit like a broken fingernail even a tiny tear can be painful and it can cause catching, clicking, locking and jamming in the knee. Again a bit like a broken fingernail by trimming off the broken bit and smoothing it over you can settle things down right away. To do this with the knee involves a 15-minute keyhole surgery procedure.

In younger people, the meniscus is tough and rubbery. It takes a significant and memorable injury to tear it. This is often a bad football tackle, a twisting injury on skis, or something similar. As we all get older the meniscus becomes more like perished rubber, or even wet cardboard, and it can tear for no terribly good reason with no memorable event. We call this a degenerate meniscus tear.

If you’ve torn your meniscus you will probably remember doing it. There will have been sudden pain either on the inside or outside of the knee. The knee may have swollen at the time or the next day and will be bad for a week or two but gradually improve. Often by about six weeks, you will have reached maximum improvement but you will probably be left with some persistent pain when twisting and squatting. You may have clicking, catching or locking in the knee. Depending on how troublesome this is you may well need help.

Some types of severe meniscus tear can cause the cartilage to flip over in the knee and jam it, meaning that you can’t get it straight. This is much more urgent and if you’re struggling to get your knee straight you should contact me immediately as in this case we can sometimes flip the piece of cartilage back and stitch it all back together getting it to heal up nicely. We call these a “bucket handle meniscus tear” and they cause a “locked knee”. A really skilful surgeon can repair these, but it is much easier to just cut it out.

If the tear was some time ago then often at keyhole surgery we would simply trim off the dead pieces and expect a really good result. In young people with a fresh tear who have come to me early, we can often stitch back the torn piece while it is still alive and restore the shock-absorbing function, protecting the knee for the future. This doesn’t work so well if many weeks have passed since the injury, in diabetic people, smokers, or more elderly people. It is difficult surgery so make sure you see a true sports knee specialist like me.

Some people manage to live with a torn meniscus without needing surgery and it is not too intrusive, but they will probably always have some discomfort squatting kneeling and twisting. It depends what you want to get out of life.  

Knee ligament injuries

MCL sprain / Medial collateral ligament

There are four main ligament groups around the knee and all of them can be injured. The ligament on the inside of the knee (we call this the MCL or medial collateral ligament) is the most common one to be injured but fortunately, this is often a sprain and is not too bad. 

It happens if you’re hit on the outside of the leg forcing that knee in the direction of the other knee, or with slips, twists and falls. You will feel pain on the inside of the knee and the knee may feel wobbly or unstable. Your body won’t want you to bring the knee out straight or fully bend it for the first few weeks (this stretches the injured ligament – so your body tries to protect it).

The good news is that most of these will heal on their own provided they have expert treatment with a brace to begin with, to prevent stretching the healing ligament, followed by physiotherapy to overcome stiffness and regain strength. The more severe injuries do sometimes need surgery so it is important to get the problem checked out by an expert who can work out what the right course of action is. 

I will usually hear your story, gently examine the knee and probably arrange an MRI scan for you. With this information, I’ll know how to use the brace to balance safe healing with avoiding stiffness and muscle wasting. I’ll also be able to see if it is such a severe injury that we need to consider surgery.

Cruciate ligament rupture / ACL tear

The ACL is the ligament injury which you may have heard more about. It’s a more dramatic injury and makes the news because it puts sports stars out of action for a season, or ends careers.

This ligament sits right in the middle of the knee connecting the shin bone to the thigh bone and is really important in keeping the knee solid and stable. Once it is torn the knee will try to give way with twisting and pivoting activities and this can often make sport impossible. 

Tearing your ACL usually requires a significant and memorable injury. Often people will feel and even hear the ligament snap with an audible pop. The knee will swell promptly and be very painful. It often involves two or three weeks of limping and difficulty bending and straightening the knee as your body gets over the initial injury. As the dust settles many people find that the knee is now loose, wobbly and unstable and will give way on them.

Some people can cope without an ACL depending on how demanding their life and pastimes are, but anyone who wants to do dynamic sport will usually struggle. For that reason, one of the most common operations I do, and what I am most renowned for, is a reconstruction of the ACL. This is an operation that I really specialise in and have developed my own techniques which I now teach to surgeons around the world. I have patients and sportspeople coming from far and wide to have their ACL fixed and we can usually get really good results. I’ve had a few world championship level athletes needing their ACLs fixed and one in particular who needed both knees doing and went on to be the world champion in kickboxing. So don’t panic, with good surgery and dedication to recovery, anything is possible. 

This operation above all others is really technically demanding to get things perfect so it is well worth picking your surgeon very carefully. Sadly there are a lot of “knee specialists” who do this operation badly. I see lots and lots of patients where things have not gone so well. There is a separate page about this ACL reconstruction surgery here.  

PCL rupture

The PCL or posterior cruciate ligament is much less commonly injured because it is one of the strongest ligaments in the knee. It can get torn by overextending (hyperextending) the knee – bending too far forwards and we see it in rugby with players tackled from the front and also in car accidents where the leg hits the dashboard. It always takes a dramatic and memorable event to rupture the PCL.

Most people can cope quite well with this injury provided they have the right rehabilitation with a complicated brace for the first few months and it is rare to need surgery if the PCL is the only ligament injured.

If the injury is missed and the treatment in the first few months is not right then this can cause problems with a loose knee forevermore and this is usually the reason that we have to do surgery. This is one of the less common operations I do. This is specialist surgery so choose your surgeon wisely! 

Lateral ligament injury / postero-lateral corner rupture

The final group of knee ligaments are on the outside of the knee and we call these the posterolateral corner. This group of ligaments can get injured if the leg buckles inwards, sometimes caused by a direct blow on the inside of the knee with contact sports, but also with other twisting injuries and things that happen at speed. There’s usually lots of pain on the outside of the knee and you’ll be limping around and struggling to fully move the knee. The knee can feel loose and wobbly and can buckle inwards.

If the ligaments are just sprained then they will often heal provided they are managed correctly in a brace from the time of injury, but if they are completely snapped or if the injury has not been treated properly to begin with then surgery to reconstruct the ligaments can be required.

This is specialist stuff so choose your doctor carefully! 

Multi-ligament injury

It is quite possible to injure more than one of the ligaments of the knee at the same time, and indeed this is quite common. A two ligament or three ligament injury is a bit more challenging and is more likely to need complex and lengthy surgery. These operations often take me a whole afternoon. These injuries don’t do well without surgery and can leave the knee very loose and wobbly making ordinary day to day life impossible.

There are a few patterns of injury that are more common than others, but often after a bad injury someone will have injured three ligaments and the cartilages, maybe with some bruising to the bone or even some fractures to the bone as well. These can be really significant injuries and require really expert surgery to get good results. As with anything severe it is important to see the right surgeon from the very beginning if at all possible. 

Cartilage surface damage – articular cartilage damage

The insides of all of our joints are lined with slippery shiny smooth articular cartilage which makes them so supple. With a knee injury, it is possible to scuff off a chunk of cartilage and bone, leaving a loose piece and a bare hole. This usually takes a memorable injury and there’s always pain and swelling as the knee fills up with blood. As things settle over the following days you’ll be left with a deep-seated pain in the knee and often the sensation of something loose moving around in the knee. It may be very difficult to take weight on the leg. 

Unfortunately, this injury is quite common in teenagers and we see it quite commonly with knee cap dislocations . It is a serious injury and if left untreated it will lead to arthritis later in life. Get it looked at quickly.

Both the loose piece and the hole cause problems and surgery is usually required. If you seek help immediately then it is sometimes possible to fix the scuffed off piece back in its hole and fix it there, but if more than about 14 days has passed the loose piece will be dead and will need removal. I will then need to try to grow new cartilage to cover the hole and there are a variety of different techniques to do this ranging from basic things like microfracture through to much more complicated things involving growing new cartilage to implant in the hole. I’m one of the few surgeons in the UK trained to do cartilage surface regeneration procedures using your own cells to generate new cartilage.

If you think you have this injury, or if you’ve recently dislocated your kneecap then it’s really important to get in touch as soon as possible.

Dislocated kneecap (Patello-femoral dislocation)

Dislocating your kneecap for the first time is always a dramatic event. It often happens due to a direct blow or a severe twisting injury. People usually end up in casualty and often have to call an ambulance.  

Some people have a certain knee shape which makes it more likely that they dislocate and this can happen if you have a high riding kneecap or a very shallow knee cap groove. Some people have very stretchy soft tissues which allow the knee to dislocate but some people are just plain unlucky. 

This injury is really painful and really distressing. The knee will look horribly deformed with a large lump on the outside of the knee (the kneecap always dislocates to the outside). Sometimes if you’re able to you can push the kneecap back into joint yourself and the sooner this is done the better. If you are lucky it may do this of its own accord and we call this a subluxation when it does not stay dislocated. 

In the aftermath of the injury, it is very important to see a good knee specialist quickly. If this condition is managed carefully then it should be a one-off. Provided you do all of the right things then there’s about a 90% chance that you’ll never have another dislocation. If it’s not treated properly the first time then it can become a problem that keeps dislocating again and again. 

If you’re in this unfortunate situation then there are some really good minimally invasive surgical options to stop that kneecap from dislocating and allow you to get your life back on track. These are operations I do quite frequently and I am very specialised in. 

Rehabilitation after a knee cap dislocation is also really important and particularly building up the VMO muscle. See some more information about this here. 

Hoffa’s Syndrome / Fat pad impingement

Every knee has a very sensitive tangerine sized piece of fat that sits behind the kneecap tendon called the Hoffa’s fat pad. If this becomes inflamed it can be a potent cause of anterior knee pain. We call this Hoffa’s syndrome.

Once the fat pad is inflamed and swollen it becomes physically bigger, making it vulnerable to getting pinched in the knee joint again causing more pain and more swelling. Quickly a vicious cycle can arise with daily pinching swelling and before you know it you have chronic anterior knee pain. 

For some reason, most doctors seem to have no idea about this condition and brand patients as having anterior knee pain without any idea why they have this pain. It is often regarded as being incurable, ‘in your head’ or something that will get better with random exercises alone.

I see this about 200 times a year, and has lots and lots of second and third opinions from around the UK and around the world! 

What are the triggers?

This can be triggered by a single injury with a blow to the knee, or by hyperextension of the knee, or it can be part of an overuse injury with repetitive trauma to the fat pad. It can also be seen as a consequence of clumsy keyhole surgery.

Common patterns are: –

  • Females who have stretchy ligaments (ligamentous laxity or hypermobility) whose knees come beyond straight.
  • Overuse in cyclists or runners with biomechanical problems, e.g. poor bike fit, or long stride length.
  • Professional sportspeople after an injury to the knee.
  • Failure to improve, or new pain, after knee surgery where the surgeon has been treating the wrong thing all along.

What does it feel like? 

You will feel pain below the kneecap at the front of the knee. It will be most prominent when the knee is fully straight and maybe worse with walking or running, but sometimes with the leg straight in bed. There is often pain kneeling. There may be a visible bulge either side of the kneecap tendon in severe cases. Sitting with the knee bent, for example, on a flight, or a the cinema can be terrible. Going downstairs can be bad. Running and cycling can be bad. 

How is it treated? 

Treatment begins with confirming the diagnosis. First I’ll listen to your story, then carry out a careful examination. Often this is all that is needed however an MRI scan can be useful to exclude other problems. Reports are often misleading as most radiologists don’t fully recognise the condition either, so I will need to look at the pictures myself.  Once we are sure, treatment can begin. 

Physiotherapy to strengthen the Gluteus Medius muscle and VMO muscle, and prevent going beyond straight at the knee, and sometimes correcting flat feet is useful. K-taping can help dramatically if used correctly.

Steroid injections to reduce the inflammation can help break the cycle but need to be administered to exactly the right spot with right dose for you. This can also be really helpful to prove that it is the fat pad that is the problem. You often need just one injection to cure you, but sometimes a series of injections is needed, or rarely arthroscopic (keyhole) surgery.

What are the results? 

The good news is that I see about a 95% success rate. I have also been through this problem myself…

Jumpers knee / runners knee / Patellar tendinitis

The big tendon that joins your kneecap to your shin bone is particularly prone to inflammation that us doctors call tendinitis. I see this more commonly in runners and people who do jumping and landing sports, and it happens because of repeated microscopic tearing in the tendon which accumulates faster than your body can repair it. 

It can happen after an increase in training, a change in training surfaces or footwear, bad sleep / inadequate rest, or sometimes for no good reason. I’ve certainly suffered from this myself a fair bit in my marathon running days.

Pain is felt just at the bottom of the knee cap where the tendon joins onto the bone. To begin with, you may feel it at the start of some sport or after exercise but as things get worse you can feel it day to day when walking around, and then all the time. Hills and stairs can be particularly bad.

Quite often physio can get on top of this and the success rate in my experience is about 50%. If you’re in a hurry, or if the condition is being stubborn then shockwave therapy is brilliant here. The sooner you have it the more likely it is to work. On average the success rates are about 75%. Rarely if nothing else has worked and if the condition is really severe we sometimes have to resort to injections or surgery. Don’t let any doctor try and inject steroid around your kneecap tendon though, there are much more sophisticated things we can inject which are safer and have better results like PRP (Platelet Rich Plasma).

If you think you have this condition then get in touch. It’s one of those things that the sooner you deal with it, the easier it is.

There is a similar condition with the tendon above the kneecap called quadriceps tendinitis. The treatment is similar too!

Plica syndrome

A Plica is a fold in the membrane that lines the inside of the knee joint. It is what we call a variant of normal, meaning lots of people have it and usually it does not cause problems. It can become irritated and inflamed as a result of a direct injury or as part of an overuse repetitive strain type problem. 

You will feel a burning type of pain along the inside upper edge of the kneecap. You may be able to feel a tender thickened band of tissue when you feel around the same area. Sometimes there is a snapping sensation as the knee moves. The onset of symptoms can be gradual and it may be hard to remember what has started it. 

It is a less common knee problem and often other doctors won’t have thought about it or even heard of it! If you think you have this condition it is well worth getting it checked out. I can usually get it fixed quite easily. It’s also worth knowing that it won’t show on an x-ray and is commonly missed on an MRI scan unless you know what to look for.

Painful knees in teenagers / Osgood Schlatters Disease

Children and teenagers who do a lot of sport quite often experience pain at the front of the knees. It’s often put down to growing pains. Actually, the most common cause is a condition with a rather long confusing name of Osgood Schlatters Disease. 

This is inflammation where the growing kneecap tendon joins on to the shin bone.  It is only really a problem during periods of fast growth coupled with lots of sport, though I sometimes see the aftermath in young adults. Near to the end of growth, the muscles and tendon become stronger than this area of growing bone, and in some youngsters, the repeated pulling on the bone can cause problems with separation of the growing bone and fragmentation. When the thigh bone is growing fast it can make the muscles tight and this makes things worse.

Teenagers will experience pain where the kneecap tendon attaches to the top of the shin bone. There is often quite a lump below the kneecap which can be sore to touch and bad to kneel on. It happens in girls at a younger age than boys.

If you think you or your child has this condition it is well worth getting it checked out. It is usually ‘self-limiting’ meaning that you will grow out of it, but there are a number of things to do to minimise the discomfort and keep you doing sport in the meantime. 

There is a very similar condition at the top end of the tendon as it comes off the kneecap called Sinding-Larsen-Johannson disease, at the heel called Severs disease, and a whole lot of other places with other funny names.

Housemaids knee / Pre patellar bursitis

This is a swelling in front of the knee that happens in people that do a lot of kneeling. There are certain jobs that make this much more likely such as carpet fitters and manual workers (the name comes from housemaids who used to have to kneel an awful lot). 

In order to protect the front of the knee, your body makes a little pouch of fluid in a sac that we call the bursa. This can become painful, inflamed, infected and sometimes gets enormous. Once it’s there it can be quite stubborn to get rid of. 

To begin with if you stop kneeling and rest it may sort itself out, but if it doesn’t then it may need some help from me. 

The options are to try and draw some of the fluid off with a needle and syringe then wrap the area with a tight bandage, sometimes adding a steroid injection to try and stop the body making more fluid and to calm the inflammation. This strategy has a reasonable rate of success but sometimes your body will keep trying to make the bursa again and it will come back. 

The more drastic option is a little operation to cut out the sac of fluid in its entirety and this has a high success rate but is more fuss and bother.

If it becomes infected then this is a serious problem and may need a trip to accident and emergency and some time in hospital on antibiotics, with or without surgery. This is one reason why it is good to get this problem sorted out quickly. 

If you’re being troubled by this condition come along and see me. I can usually get rid of it and cure you in one way or another. 

Ilio-Tibial Band Friction Syndrome – ITB / ITBFS

This is a common cause of pain on the outside of the knee particularly in sports such as running and cycling but I also see it in patients who have had knee replacements. It is caused by a tight band of tissue called the ITB rubbing on the bones around the edge of the knee as the knee bends and straightens. This causes inflammation and a strange burning pain down the outside of the leg sometimes spreading up and down the leg.

It can be quite hard to put a finger on where the pain is. Often the pain will build up during a run or bike ride until it becomes excruciating and unbearable. I’ve suffered from this myself and it was a very predictable time and distance into each run when I started to feel it. 

Less experienced doctors can find it quite difficult to get the right diagnosis and there are lots of things that can cause pain in this region. One other condition that is commonly mistaken for this is biceps tendonitis where the pain is a little bit lower down. I’ve had this from racing up the Alps on a bike.

By listening to your story carefully and gently examining you I can usually make the diagnosis quite easily. An ultrasound scan can sometimes be really helpful if no one is quite certain of what the cause is. 

There are a few different ways to treat this condition ranging from physiotherapy and some very specific exercises through to injections, shockwave therapy or even a tiny little operation. I can nearly always cure this problem. 

If you’re being troubled by pain on the outside of your knee consider whether this could be the cause and if you need help with it please don’t hesitate to get in touch. 

Biceps tendinitis (lateral knee pain)

This is one of the many slightly unusual causes of pain on the outer aspect of the knee. It involves inflammation of the bicep femoris tendon; one of the hamstrings that joins on to the shin bone at the level of the knee (not to be confused with the bicep muscles in your arms!).

I see this condition in cyclists doing a lot of climbing especially out of the saddle, but can happen in all sorts of sports. There will be a rather vague pain on the outer side of the knee, which builds up and gets worse and worse. When the condition is really severe it may trouble you day to day. 

By listening to your story carefully and gently examining you I can usually make the diagnosis quite easily. An ultrasound scan can sometimes be really helpful if no one is quite certain of what the cause is. 

There is a range of different ways to treat this condition from physio with some loading exercises, injections, or shockwave therapy. I can nearly always cure this problem. I have had it myself.

Bakers Cyst / Swelling behind the knee

This is swelling a the back of the knee. It is usually uncomfortable or downright painful, and it can limit the amount that you can bend your knee. It might stop you from squatting or kneeling. 

It gradually creeps up on you until you notice it one day. The swelling can sometimes be bigger and sometimes be smaller depending on what you’ve been doing.

This usually happens because there is some sort of problem elsewhere in the knee and it’s really a sign of another problem rather than a problem in its own right. An analogy I often use is; it’s like clouds of smoke coming out of the back of your car. The solution is not to hoover up the smoke, but to look at the engine. 

For that reason, the patients that I see with a Bakers cyst often end up having the problems within their knee fixed, then the cyst goes away of its own accord. I commonly see it in people who have knee arthritis or a torn meniscus in the knee.

Usually, it won’t go if you leave it, but sometimes it will get so big and so tight that it bursts. If this happens you will feel a pop and the sensation of warm fluid running down the back of the calf. The good news is that when they burst, they tend to go away for good.

Is not a dangerous condition and if it’s not troubling you too much you can choose to live with it. Usually, it is the underlying problem that will catch up with you one day.

If you think you have a Bakers cyst then do get in touch and I’ll see what I can do to help you. 

Frequently asked questions

Kind of! I can refer you in to my team in the NHS, but not to me personally, so it is most likely that you would be seen and operated on by a junior doctor acting in my name.

I hope so! I see lots and lots of patients who have been elsewhere and then come to see me, including tricky problems from around the world! Because I am trained in orthopaedics, sports medicine and sports psychology, and because I have had so many of the problems myself I can often give a fresh perspective.

It's probably best not to. Not everyone needs a scan and sometimes it is something other than an MRI. Also not all MRI scans or scanners are equal, so it is better to wait until I have decided what we need. I can also get the scans done at a special lower cost for you!