There are 5 types of plicae in the knee. The two most well-known plicae are the mediopatellar (medial) plica placed on the inner site of the kneecap and the other one is the infrapatellar plica (ligamentum mucosum) placed in the front of the knee. All the five plicae have no known functions, but they are residuals from the fetal life.
An impact on your knee or a wrong use, can cause your plica to get inflamed and then it gets swollen. The medial plica are known to catch between the kneecap and the femoral condyle and this typically causes symptoms of inner site pain and catching. The Infrapatellar plica is attached to the Hoffa Fad and moves significantly when your knee straightens and bends. Sometimes scar tissue in the infrapatellar plica can cause anterior knee pain based upon scar tissue in the plica makes it shorten up.
First of all the treatment focus rest and anti-inflammatory medicine (NSAID or steroids). When your plica has restored it self, a physiotherapist can help by restoring balance and correct movement patterns to prevent recurrence. Sometimes those treatments are not sufficient and your plicae may have to be taken care of by arthroscopic surgery. Here it is very easy to remove. Some call the Infrapatellar plica problems arthrofibrosis and call the procedure arthroscopic removal of the plica - anterior interval release. Personally I do not think this is arthrofibrosis, which is a much more serious condition giving you a stiff knee.
The three other plicae are the Suprapatellare plica that occasionally can give rise to pain above the patella in the Quadriceps tendon. The Laterale plica, that can cause outer site pain. And finally there is a plica that is localized in the rear of the knee and act as valve in front of a Baker cyst.
In case you a having a knee problem, in most situations it will be helpful for you to have an MRI scan of the knee - to make a diagnosis or to support the diagnosis or to exclude other reasons for your problem. MRI scans are really good for seeing meniscus tears, anterior cruciate ligament (ACL) tears and other ligament tears. The price has also declined in the past years and today it is close to 400 euro in Denmark. If your main problem is knee pain, I believe you should in most circumstances have an MRI scan of the knee and you should not have an arthroscopy without the MRI.
MRI scan is a magnetic resonance scan and by having a different magnetic field gradients it can generate images of the knee. Both open and closed MRI scanners exist and as far as I know, the quality from the closed ones is always better. You are supposed to lie supine, and claustrophobia is seldom a problem since your head is out site the machine.
In most situations it is very precise, however there is a number of exceptions. I will try to explain some of those here and what you need to be aware of. First of all an MRI of the knee not a answer book. A good clinical examination, in combination with your history about how the problem started and what type of pain or problem you might have, can been even more precise. Some things cannot be found by either a clinical examination or by an MRI scan and you may need to undergo an arthroscopy of your knee.
One of the problems with MRI scans is that the result relies on who is looking at the pictures. Normally the radiologist very good, but they may overlook things and some things might be so special that they even do not even know about it. Sometimes the radiologist has not received the appropriate information from the orthopaedic surgeon that is actually needed to look for a specific problem. The radiologist sends his report to the orthopaedic surgeon. Some orthopaedic surgeosn only look at this report and do actually look at the MRI scan pictures themselves. If they do, they may not know precisely what to look for if it is something rare. The main reason why I write this is not to scare you, but to make you aware that if you are in a situation with continuous pain and you have been told that the MRI is absolutely normal, you might need a second opinion.
I believe that one of the most common reasons to have anterior knee pain, and where also the findings seems to be normal, might be a synovial plica, since this structure can be difficult to evaluate on an MRI. Also trochlear dysplasia is often overlooked as well as patella alta. So the reason for this might be that the radiologist and/or the orthopaedic surgeon do not know how to precisely measure this. At least in Denmark some departments have cancelled the axial view, in order to save time and money. Nevertheless the axial view is the most important view in respect to kneecap instability and anterior knee pain, since this is where the trochlear dysplasia is noticed and the lateral trochlea inclination angle, the trochlear asymmetry and the TT-TG or TT-PCL is measured. So if those measurements are not mentioned and you are dealing with kneecap problems, ask the orthopaedic surgeon about those and if he does not know how to measure, perhaps you should ask for another orthopaedic opinion.
If a meniscus tear is suspected you can be 90% or more sure that the MRI will reveal this tear. However in some situations you can be unlucky that the tear is localised just between two MRI slices and therefore not visible. You might also have what is called a meniscus ramp lesion, that means that the meniscus is torn from the capsule in the rear part of the knee and is frequently associated with anterior cruciate ligament (ACL) injuries. The meniscus ramp lesions can be difficult to see both on MRI and during arthroscopy and are often overlooked. Also meniscus root tears might be overlooked on the MRI scan and "just" called a radial meniscus tear; however this type of tear can be very detrimental to the knee and in most cases surgery is indicated and that means the tear needs to be fixed or cut away.
In the figure on the left you see the knee from the side and there is a meniscus ramp lesion; however it is rather seldom the lesion is so clearly seen. Often such a lesion can be overlooked based on a little scar that covers the lesion, and this does also apply during the arthroscopy, and therefore careful exploration might be necessary.
In most situations an ACL tear is seen very precisely on MRI; however there are exceptions. In some cases the ligament is not torn, but just overstretched and has becoming too long. This can be difficult to see on an MRI, but a clinical examination will in most situations reveal this. If you already have had an ACL reconstruction and your knee has become loose again, this can be difficult to see on an MRI, since the ACL graft will in most situations not become torn, but just slowly gets longer and longer.
MRI scan can be very clear on large cartilage lesions, however smaller lesions can be difficult to detect and in those situations is the arthroscopy much more precise.
Just a little about MRI scans of the knee and what you should be aware of
Here you see a lateral trochlear inclination angle at 7 degrees, which is a little below 11 degrees that is the threshold for calling it trochlear dysplasia. The normal angle is 21 degrees. It is important that the measurement of the inclination angle is done at the most proximal axial view, where both of the posterior femur condyles are seen. The lateral trochlear inclination angle varies substantially from the top of the groove (caudal) to the bottom (distal).
The patellotrochlear index is a more clinically relevant measurement of patellar height than other types of measurements. It is a measurement that says how big is the overlap between the trochlear groove and the kneecap. This is the only correct way to measure the height of the kneecap, and old measurements like the Insall-Salvati and Caton-Dechamp indexes are obsolete and imprecise. Those measurements do not say anything about the articulation between the patella and trochlea, and that is what patella alta is all about.
Above you see a figure that demonstrates a high-riding knee cap (patella alta) and you also see an arrow that points to a white area. The white area is increased water content in the fat pad and this means inflammation. The inflammation is caused by the late engagement of the patella in the trochlear groove. The patella will first engage into the trochlea area when the knee is flexed several degrees, and that causes too much load on the fat pad and this causes the inflammation.
In every knee there is an inner and an outer meniscus. They job is to resorb the forces between the femoral and tibial condyles as they act as shock absorbers and distribute the pressures. The meniscus can get injured and there are several types of tears depending on the type of injury. The typical mechanism of trauma is is a twist of the knee, but the injury can a occur spontaneous during running or by squatting.
In some cases of a meniscal tear an arthroscopy is needed. Typically you either cut out the damaged part of the menisci or in other situations it is possible to repair the tear by using different kinds of meniscal sutures or anchors,In most cases the meniscal tear can seen on an MRI scan, while and ultrasound scan is unreliable.Sometimes the injury is so obvious, that you go directly to an arthroscopy.
The symptoms for meniscal tears are commonly pain in the knee aggravated when the knee is loaded and especially by doing turns. This can feel like something is catching or like sharp pain. Please see below if some of the seven classic symptoms are some of those that you experience.
Not all meniscal tears need surgery and especially in middle aged persons the symptoms can resolve, eventually helped by steroid injections and physiotherapist guide rehabilitation.Meniscal transplantations is an option in special selected cases, either by artificial menisci or by allograft menisci (menisci from (harvest from a cadaver).
If you have a meniscal root tear you need surgery. This is based upon that the meniscus loose the ability to work as a shock absorber, when there is an avulsion of the meniscal root. Then the wear of cartilage will increase and this causes pain and early osteoarthritis. Unfortunately is this type of tear often overlooked by surgeons, since they are not aware that type of injuries exist. The problem is also that many radiologist, who are the ones who where supposed to see the injuries by MRI scans, also overlook those injuries. Read more here.
What if meniscal root tears are not operated? Read here
Meniscal tears and cruciate ligament tears often are associated, and sometimes there is also and injury to the site stabilising ligaments. My opinion is that in those situations, where you do surgery for a meniscal tear, you might as well do an concomitantly ACL reconstruction. Then you are only needed to have surgery once. If a meniscal tear is sutured, you must also stabilize the knee with an ACL reconstruction, otherwise will the meniscal repair retear.
There exist many types of knee injuries and here is anterior knee pain, jumpers knee, runners knee and pes anserinus pain, some of the most common, and those could be caused by overuse.
Tibial osteotomy is also called a bone wedge operation, since you either do have taken out or inserted a bone wedge in the shin. The tibial osteotomy can be useful if you have osteoarthritis, which means damaged cartilage on the inner or outer site of the knee. If you are bow legged you will have increased load on the inner site of the knee (varus knee) and just upper site if you are knock legged (valgus knee). By a tibial osteotomy the angle in the knee is corrected and the leg is realigned. This means that the high forces on the damaged part of the knee is moved towards the other site of the knee where the cartilage is good. By unload the damaged cartilage the pain can slowly resolve and the damaged cartilage can regenerate over time. If you are a tibial osteotomy the time for a total knee prosthesis can be exposed a number of years. Precisely how long is difficult to say, since it depends on the severity at the time of the surgery, but from 5 - 20 years is realistic. The earlier the longer. Before the surgery you have to undergo a special x-ray examination to see calculate the precise angle of correction needed. The information further down is in respect to when you are bow legged, since this is must more common.
An alternative to surgery is that you use an unloader brace. You then use the brace when you are loading your knee while walking or running. The princip is a spring built into the brace and this absorbs the load on the inner site of the knee. See video hereSe video her
By the surgery the shin is opened on the inner site, and by using a special guide system the bone is cut 3/4 though and a plastic wedge is inserted that precisely corrects the preoperatively planned correction. By this the leg will get about a ½ cm longer. The plastic wedge is secured by four plastic screws. The plastic material very much mimic the bone and can be left and normally it should not be removed. The IBalance method is now 10 year old and is very secure and precise and has many advantages in comparison of using a metal plate. Sometimes a corresponding arthroscopy of the knee will be done.
You will arrive to the recovery room and I will inform you about the surgery and you will receive the surgical report before you leave.
During the surgery local anesthetic will be applicated around the knee and this last for some hours. Sometimes the anesthesiologist doctor will supplement by a nerve block. It is normal that you will have some pain for the first weeks and you can reduces this by placing some ice wrapped in a towel on the knee. This can be applicated for 20 minutes every hour.
You will be mounted with a brace where you will be able to bend your knee. This brace is going to be used for 8 weeks and is going to protect you leg to brake until the bone has healed sufficiently. After 2 weeks the brace can be opened safely when you sit in a sofa. After 4 weeks you can omitted the brace while sleeping and in the bath. The first 2 weeks you are only allowed to load your leg with 5 kg and after the 2 weeks you are allowed to load by 20-40 kg (if you are in doubt how much this is then take a bathroom scales). After 4 weeks you are allowed full weight bearing. You have to expect that the lower leg including the foot will get swollen the first weeks after the operation. It is also common to get some bruises and some stinging (can be reduced by NSAID ointment). To prevent deep venous thrombosis you have to take a preventing pill once a day for 10 days. It is common that you need to take some strong painkiller after the surgery such as morphine and morphine often cause constipation. Therefore it is a good idea to prevent constipation by taking some laxatives. The site effect for this can be epistaxis and bruises and if this occurs you should only take the pill every second day. You are likely to get a palm large area with less sensation on the lower limb. Rarely some patients experience severe foot pain for the first 2 weeks.
This demonstrate a person having varus knees and in the right knee you see the line representing the axial load and this is going to the inner site of the knee
Tibia osteotomy of a left knee before and 1 month after surgery. The transparent area is the plastic Ibalance wedge
So why chose a tibial osteotomy instead of a knee prosthesis or a uniknee? First of all a knee prosthesis is not a new knee, but a combination of metal and plastic to restore the weared cartilage. A knee prosthesis is a major surgery and it is always better to preserve your own knee if possible. The results after tibial osteotomy seems today to be better than previously and better compared to having a knee prosthesis. One advantage is in average better range of movement. In general 20% says they are happy, 70% are good and 10% is bad and needs a knee prosthesis.
Read more: http://oeg.dodec.co.uk/
Above you see a right knee with the line of load going through the inner site of knee
Below you can see the IBalance Tibial Osteotomy system, which are having many technically advantages compared to previously known methods. First of all it is more secure and precise. Since the plastic (PEEK) wedge is placed in site the bone is the no plate to protrude and bother. The plastic material can be left in place. This means no need for further surgery and in case you later need a knee prosthesis the wedge can still be left in place.
Du henvises til genoptræning som typisk starter 14 dage efter operationen.Træningen sigter mod at genoprette bevægeligheden i knæet og genopbygge muskulaturen i benet og genoprette balancen.Dit liv vil i en periode være besværliggjort og du vil i specielt de første 2 uger have svært ved at komme rundt med krykkestokke, fordi du ikke rigtig støtter.Du må først genoptage bilkørsel, når du i relation til benet kan føre bilen sikkert ogdette er typisk 4 uger efter operationen, dog lidt hurtigere for venstre ben end for højre ben.12-14 dage efter operationen skal du have fjernet trådene hos din egen læge. Du skal have taget røntgenbillede 4 uger efter operationen og efterfølgende skal du til kontrol hos mig, for at se hvordan helingen ser ud på røntgenbilledet. Der vil også være en kontrol igen 3-4 måneder efter operationen. Det er ikke ualmindeligt at der går mange måneder inden knæet falder til ro efter operationen.
Rarely postoperatively infection can occur, but in those cases it is seriously and need instant treatment. In rarely cases will the bone not heal and new surgery is needed.
If your Patella is placed to high in relation to the groove (Patella alta), the Tibia Tubercle Transposition can bring your Patella downwards into the groove. If the Tibial Tubercle is outward placed, your Patella tends to track outwards and by medialization (moving inwards), your patella will track more correctly. The surgery should only be performed if you are having either an increased TT-TG or an increased Patellotrochlear index - read more here. A little variation of this surgery is called Fulkerson osteotomy and this can be used for a special group of patients having anterior knee pain caused by osteoarthritis in the Patellofemoral joint.
As it appears from the picture at left, the Tibial Tubercle is chiseled off and moved inwards. The bone block is fixated again by 2 screws.
This demonstrate a Patella Alta - meaning a high riding kneecap
The distalisation of the tibial tubercle have brought the patella into the trochlear groove
By MPFL reconstruction surgery your injured inner ligament for the kneecap (MPFL) is replaced by a stronger ligament that keeps the patella (kneecap) in place. The ligament goes from the inner site of the patella and the quadriceps tendon towards the medial femoral condyle. The ligament is typically harvested from the back site of the thigh, by an incision over the inner site of the tibia.
Many surgeons say that you will just need an MPFL reconstruction and there is no reason do for example a trochleoplasty.
It can be right that MPFL reconstructions are very good in most situations. Nevertheless is the MPFL reconstruction just a new ligament and just like a shoelace, there is risk that it will not last more than a few years. This can be the case if there is trochlear dysplasia etc.
Unfortunately I see a number of patients who had MPFL reconstruction that re-rupture. I also see a number of patients who just have pain at the inner site of the knee, based on too strong forces on the ligament. Therefore make sure that you have an MRI scan and that your surgeon knows how to look for trochlear dysplasia and patella alta and increased TT-TG distance. Eventually read more here
New data indicate that the long term results are not as good as we had hoped. Check here
This demonstrates how the new MPFL ligament looks like from the side.
Left is an example that demonstrates how an MPFL reconstruction can be performed - the picture shows how it looks just before inserting the screw that is going to secure the ligament until it has grown tight to the bone after a few months.
What are you allowed to do and what can you do after an MPFL reconstruction? Normally do I never prescript braces after an MPFL reconstruction. You are allowed full weight bearing and free range of movement. Already a few days after the surgery I recommend that you start to do physiotherapy guided exercises in order to regain strength and ability to bend your knee
For how are you going to stay away from school or work? This is a very good question, since there is huge individual variation. Some will be already back after a week, while for those have heavy physical work it may take 2-3 month. Another thing of importance is how you transport yourself from home to school or work
When are you allowed to return to sport? This depends on what type of sport you participate. If it is contact sport you have to wait until the muscles are finally back in force and balance, however you always need to wait at least 4 month..
What safety level of activity is recommended after MPFL reconstruction?Normally I do not use any brace or limitation in range of movement and I allow full weight bearing. A few days after surgery physiotherapy-guided exercises are recommended.
Trochleoplasty is a surgery for the Trochlear groove, a groove that helps the kneecap (the Patella) to stay in place. By this surgery a new and a deeper groove is created to normalize your anatomy.
If you are troubled by unstable kneecap or chronic anterior knee pain, you might also have an abnormal groove. This means that the groove for your kneecap is more shallow than normal or it can be even flat or convex. In short, when your knee groove is too shallow, this tends to make you kneecap unstable. It basically means that it might either go half the way out (called subluxation) or it even dislocate. The condition of having a shallow groove is called trochlear dysplasia (abnormal groove). In these cases were you groove is flat, this special operation might be the best option for you.
We know when your groove is shallow or flat, it is a result of too much bone in the center of the groove. This basically means that you have too little bony support for the kneecap.
The principle of the groove surgery is basically to deepen the groove. First is the cartilage released from the groove. Subsequently excessive bone is removed. This is followed by creation of an outer bony wall to support the patella. After that, when the groove has been deepened and re-shaped, the cartilage is re-located by means of a special blue or white bands. Those tapes or bands are later resolved. You can find picture examples by the images below. Certainly the groove operation is, from a mechanical point of view, the most anatomically correct operation to perform, if you have an abnormal groove.
For the past ten years I have done more than 100 arthroscopic deepening trochleoplasty procedures. Before I invented this arthroscopic trochleoplasty, I used to do the groove procedure open. I have stopped to do the open surgery. since it leaves a bigger scar, and in addition it is more painful.
By using the pinhole technique (arthroscopic), consequently the surgery becomes less traumatic for your knee , and therefore the rehabilitation is likely to become accelerated. To notice is the groove operation mostly done in combination with a reconstruction of the inner ligament for the kneecap (MPFL reconstruction).
Why is the groove surgery not enough? And why should you also have reconstructed the MFPL? (mediale patellofemoral ligament = inner ligament for kneecap). That is first of all because the MPFL is always torn when the kneecap dislocate. It does not heal normally and therefore it has to be reconstructed. Moreover it also so, that the trochlear groove, do not provide stability to your kneecap, before the kneecap reach the trochlea. Importantly this first happens after your knee is bend about 20 degrees. This means that the MPFL is needed to provides stability to your kneecap from full straightened knee and until your kneecap reach the new groove at 20 degrees of bending. Read more about MPFL reconstruction here
If you problem is chronic anterior knee pain as a consequence of a too shallow groove, and your kneecap is stable, likewise you do not need to have the ligament to stabilize the kneecap reconstructed - eventually read more in the page about anterior knee pain.
In case you would like a second opinion regarding your MRI or just your general knee situation, I do Skype consultations. The cost is 150 euro - email [email protected]
You can eventually go to Facebook. Check out either "Lars Blond + Trochleoplasty" or just "Trochleoplasty". Here you can notice more details and recent updates
Aleris-Hamlet Parken has very high safety. A rate of infection close to zero and with high cleanliness and has undergone accreditation after the highest international standards and use the latest technologies. All doctors are experienced doctors. All personnel speaks English.
Before (left) and after (right). The blue band dissolves after 6 weeks and is therefore only temporary until the cartilage has healed.
- "It is difficult to balance a tennis ball on a football"
Two different examples of how it looks in-site the knee 3 months after a groove surgery. If you notice has the cartilage healed very nicely and blue bands/tapes are dissolved.
Illustration showing the tapes in place after arthroscopic trochleoplasty
Nice small scars after combined arthroscopic trochleoplasty and MFPL reconstruction
Eight weeks after the surgery and the scars will become much more nice over time. I recommend you to use tape in the first month after surgery, since this will reduce traction in the scars. Hence you can avoid that the scars becomes wide.
Video arthroscopic trochleoplasty
Kenneth doing well one year after
That is a good question and some surgeon argue that it is not necessary. Nevertheless, sometimes I see patients having trochlear dysplasia and who have had an MPFL reconstruction only. Then after some years the kneecap starts to becomes loose again or they develop a painful knee. Therefore if you visit a surgeons, who do not do trochleoplasty surgery, and you do have this flatt groove. Most importantly try to get a second opinion in case this surgeon tells you that the surgery is rare, dangerous and complicated surgery since this is not correct.
Mikkel was the first patient who was operated upon with an Arthroscopic Trochleoplasty, and this was back in March 2008. Previously he had unsuccessful kneecap-stabilizing surgery and by doctor and physiotherapist he was told that he would never be able to sports again. Most noteworthy Mikkel had been troubled in both his knee since he was 8 years old and had never been able to run. Finally he underwent surgery on both his knees with the groove surgery at 29 years old. Meaning 21 years without running.
Today is Mikkel doing well in his knees and he is running and playing soccer. He claims that the only annoyance is the sound from the knees, when he climbs stairs. Go to YouTube and listen to his and other stories during the trochleoplasty gathering in 2014. Many thanks to Asker Blønd - my son - who created this video. Click here trochleoplasty gathering.or check this video
Generally the outcomes after groove surgery is very good, with less than 2 percent new dislocations. Consequently is the quality of life dramatically better. I have followed all my arthroscopic trochleoplasty patients for now more than 10 years and in average there as been improvements in all measured parameters and high satisfaction. Both the technique and the results of this operation, have been published in peer reviewed journals. Today I have presented "The Arthroscopic Deepening Trochleoplasty" technique in the United States, Japan, Netherlands, UK, Sweden, Norway, Poland, Germany, Austria, Portugal and China. Moreover has the surgery been adopted by other surgeons and is now performed in ten differnet countries world wide.
What about having a TT osteotomy instead of a groove surgery? The fact is that no surgeon know what exactly what is best since the science has not yet given a final answer to that question. However is there many indications that the groove surgery gives better results. In addition we know that trochleoplasty surgery normalize the anatomy. Moreover does we know that patients, who have had TT surgery after a decade are having declining results. The first trochleoplasty patients I operated more than 13 years ago are still doing fine. So based on this and my clinical experience by doing both many tibial tubercle osteotomies an trochleoplasty surgeries, I prefer to do trochleoplasty if you are having severe trochlear dysplasia.
Below you can find four examples on MRI scans, demonstrating the most upper part of knee with a shallow groove, flat or even dome shaped groove, and this is called Trochlear dysplasia. Trochlear dysplasia can lead to both patella dislocation, anterior knee pain and cartilage breakdown. The thinning of the cartilage is based on too much load on the cartilage and therefore it also predispose to osteoarthritis . Why do you get trochlear dysplasia? Basically this is unknown, however there is some heredity and also breech position during foetal life may also have importance. I have been told by a patient having trochlear dysplasia that the history of loose kneecap could be traced seven generations back in time. Sheila Strover can explain so it is more easy to understand - Click here
Unfortunately is trochlear dysplasia very often overlooked by the radiologist or/and the orthopaedic surgeon on the MRI and X-rays
The lateral trochlea inclination angle is regarded as the most important measurement for evaluation of Trochlear dysplasia. This is the angle of the outer part of the groove (Trochlea), compared to line in the back of the knee between the two femur condyles. In other words the more steep the outer edge of groove, the more stability it provides for the kneecap, thereby preventing for coming out of the joint. Further if the angle is below 11 degress it means trochlear dysplasia (shallow groove). Pleae notice the examples below - left is normal - right demonstrates trochlear dysplasia. Read more here
When the knee cap tilts, it´s rarely because the lateral ligament is to tight. Importantly the tilt is caused by trochlear dysplasia, meaning there is too much bone in the trochlea. Consequently this causes the knee cap to only articulate on the outer part of the knee cap. Moreover this typically gives anterior knee pain or hyperpressure syndrome, based on to much pressure in the patellofemoral joint. In these cases trochleoplasty could be the right solution, since it reduces the pressure.
Patella tilt - Trochlear dysplasia
Patella tilt - Trochlear dysplasia
This means Tuberositas Tibia - Trochlear Groove distance. The measure is done by CT or MRI scans. It explain how much offset the groove has in relation to where the patella tendon attaches to the tibia (Tuberositas Tibia). TT-TG distance is normally about 9 mm and if it´s more than 14 mm on MRI scans or 15-20 mm on CT scans, it´s too high.
This is a MRI picture that demonstrates a slice of a normal knee, demonstrating the kneecap and the trochlear groove
Severe increased TT-TG distance on a CT scan in a knee having a degree of trochlear dysplasia
This is a drawing of how you measure the TT-TG distance. Two axial slices from the MRI or CT scan are overlapping or superimposed and thereby you can measure the distance.
Just a drawing of the same picture at left, demonstrating a TT-TG distance above 40 mm which is extreme. Dejour type D.
Henry Dejour has made a classification that was later updated by Tecklenburg and David Dejour, having four subgroups. The classification is based upon x-ray examination. It contains Dejour type A,B,C and D. Since we mainly uses MRI or CT scans today and since the classification is with rather low inter correlation (means that is not precise), I use instead the lateral trochlea inclination angle, together with some other measurements, such as Anterior Posterior measurements from Biedert and trochlea asymmetry.
Bieder Anterior Posterior measurement
For some patients with kneecap laxity the kneecap will goes out once and they will experience no further problems. Others, however, may go on to experience repeated dislocations. If the kneecap has gone out more than once, it will have a tendency to out again and again, and then things may become quite disabling. The problem can occur while doing activities, like changing direction such as in sport or dancing, while for others the kneecap just seems to go out without much provocation, and this can happen while walking on uneven or slippery surfaces. In some of the worst cases you need to concentrate on avoiding the kneecap popping out the groove while kneeling, jumping in and out of a car or during sexual activity. Quality of life can be significantly affected, since a lot of simple daily activities must be avoided. Sometimes the disorder also causes pain during daily life. It is very important if you are going for surgery to rule out what cause your instability, since the surgery should correct the identified abnormality (or abnormalities, since there may be several factors involved).
It is very important to find out why your kneecap dislocated, since there are so many treatments and in order for you to have the right one, this have to be examined. This is rather complicated and I have made a site only for explaining this in order for you to ask you surgeon the critical questions - click here
Many myths exist about loose kneecap, and one is that you will grow out of it. Mostly this disorder is worse during the teenage years and then you learn to be more cautious and reduce your level of activity. There is furthermore a tendency for the joint to get less flexible as you age and this helps the kneecap to stay in the groove. So many grownups do not actually grow out of the condition - they just learn to avoid the activities that provoke the dislocation.
Another myth is that the disorder just needs to be trained away. This is only partially true. Some may perhaps be able to avoid surgery by learning to use their knee in a more correct way via physiotherapy and by strengthening the quadriceps and gluteal muscles. A special brace that supports the kneecap (for example DJO Tru-Pull) can stabilise the patella. There is yet no scientific documentation that say that physiotherapy can prevent further dislocations
The next myth is that surgery can easily treat the disorder. A significant number of patients undergo surgery only to experience that the surgery did not work as intended. As previously mentioned, is of importance to explore the reason why the kneecap dislocates - for example by MRI - so that the surgery can be individualised and thereby work efficiently.
The next myth is this disorder is inherited. Actually this is true in several cases, and sometimes a dislodged kneecap can be traced back several generations.
A further myth is that if you had once undergone surgery, and it did not work, that you just need to live with your symptoms. Unfortunately this is a disorder where many patient have undergone surgery using an insufficient method, and this explains why it did not help or maybe even worsened the situation. Knowledge about this disorder has changed radically over recent years and if the right surgery is done, there is a very good chance for your knee to become significantly better.
When the kneecap jumps out it is naturally a very unpleasant experience and often the kneecap has to be manipulated back at the emergency department. The first time the kneecap dislocates, a ligament on the inner side is torn (this is called the Medial Patellofemoral ligament - MPFL). Such an injury causes a lot of pain and swelling and sometimes a fragment of the knee cartilage is loosened. In some cases a loosened piece of cartilage requires surgery to fix the piece back in place or to remove it.
For those troubled by a continuously loose kneecap there will be a huge variability how much distress this actually causing. However questionnaires have been developed to help both patient and surgeon to elucidate the extent of the problem. Please see an example of a questionnaire here. As previously mentioned is it not always that the kneecap jumps out again, but still it can be troublesome since the person may experience that it nearly jumps out (which is called subluxation).
The first time the kneecap goes out, the treatment is likely to just consist of rest, ice, compression and elevation (RICE), while allowing full weightbearing and full range of movement. In past years a brace for support and immobilisation was generally used, but recent research has shown that it does not have any real impact. If the knee does not get the stability wanted and the kneecap continuously is feeling loose a kneecap stabilising brace or surgery should be considered. Physiotherapy has also been an important part of the treatment in improving muscle balance, but studies have not really demonstrated that it has a positive effect on the patellar looseness itself. Please read more about surgery here; MPFL reconstruction - Elmslie-Trillat surgery - Trochleoplasty
The condition of a loose kneecap has many names and here you can learn more about: dislocating kneecap, kneecap out of its groove, kneecap out of its socket, kneecap malalignment, slipped kneecap, jiggly kneecap, unstable kneecap, recurrent patellar instability, episodic patellar instability, luxating patella, unstable patella...
The condition of a loose kneecap has many names and here you can learn more about: Dislocating kneecap, kneecap out of groove, kneecap out of socket, kneecap malalignment, slipped kneecap, jiggly kneecap, unstable kneecap, recurrent patellar instability, episodic patellar instability, luxating patella, unstable patella
The inner side and outer side ligaments are also referred to as the medial and lateral collateral ligaments (MCL and LCL). Those two ligaments gives sideways stability - and those can be partially or totally torn by a knee twist. The treatment of the two ligament injuries is different.
The mediale collateral ligament normal heals sufficiently by itself in opposition to the lateral collateral ligament. The MCL tear is treated by a site to site stabilising brace, having normal range of movement and full weight support. Normally the MCL ligament is sufficiently healed to remove the brace after 6 weeks. The LCL is typically injured together with the ACL and the recommendation is always repair/reconstruct since the tears seldom heal by themselves.
Another ligament that has been given much attention lately is the Antero Laterale Ligament (ALL) and that is an important ligament that protects the knee towards too much rotation in relation to the femur. It can sometimes be needed to reconstruct that ligament simultaneous to the ACL reconstruction.
Cartilage lesions in the knee are common.The cartilage is a very important surface covering the bone. The cartilage is surprisingly most of all made of water and is extremely slippery in order to make the joint go smoothly and the cartilage is an important shock absorber. It is difficult to compare the cartilage with anything we know from daily life, but think about it as the peel from an orange. The cartilage can be torn off by a sudden twist or hit. The cartilage flake can float around in the knee as a loose body and cause sudden locking when it catches. The area where the cartilage is missing is a cavity, and potentially this can cause pain and mostly the knee will becomes swollen. Many cartilage lesions will slowly recover without any treatment, however some lesions continue to cause knee pain. Osteoarthritis in the knee is also a kind of cartilage lesion, however in this situation this is more a kind of cartilage thinning, based on decreased cartilage quality over time causing the cartilage to fragment and wear.
So at one end of the spectrum we do have cartilage lesions in the very young with fresh cartilage, and in the other end of the spectrum there is older people, where the cartilage starts to breakdown for more or less unknown reasons. In the middle between those types are all kind of variations. The treatment of the different types are different and this naturally makes this area of treatment very complicated. A lot of science is ongoing but still the big breakthrough is lacking. I am personally working with a study on Lipogems for treatment of osteoarthritis. This is micro-fragmented adipose tissue containing stemcells.
Treatment of cartilage lesions
Cartilage lesion in younger people (here is meant below 40 years) is typically treated by microfracture (Steadmann).
This is a treatment based on arthroscopic cleaning of the lesion and then small holes in the bone is applied to the button of the lesion directly into the bone. This causes some of the bone marrow and blood to float into the defect and fill it. Over time this will mature into some cartilage looking scar tissue. When such a treatment is done, the knee must not be loaded for 8 weeks, since the area has to mature in order to stand the forces. It normally takes one year before the repair tissue is 100 % healed. Unfortunately does about ⅓ not heal and in those cases a lot of advanced methods exist.
The most famous is cartilage transplantation (autologous chondrocyte transplantation - ACI). This method was started already in 1987 by Mats Brittberg and is therefore a well known technique that has been refined many times. Most people ask why not start with this instead of microfracture? The short answer is that it is troublesome and very costly and the results are only minimally better. By cartilage transplantation we harvest some cartilage and this is then regrown for some months, and then the cartilage cells are transplanted into the defect by another operation.There has been attention drawn to the issue that some cartilage lesions never heal because of underlying malalignment and axis deviations. Those knees must have they imbalances simultaneous corrected by osteotomies - see for example tibia osteotomy or trochleoplasty or tibial tubercle osteotomy.
All knees do have a plica placed on the inner site of the kneecap (parapatellar) and one in the front of the knee (infrapatellar). The inner plica has no know function, but is a residual from the fetal life. Sometimes a knee impact or wrong use of the knee can cause this plica to get inflammed and the it gets swollen and catch between the kneecap and the femoral condyle. The treatment focus rest and antiinflammatory medicine (NSAID or steroids. When the plica has restored it self, a physiotherapis can help by restoring balance and correct movement patterns to prevent recurrence. Sometimes those treatments are not sufficient and the medial plica has to be taken care of by arthroscopic surgery, where it easily can be removed.
The infrapatellar plica is attached to the Hoffa Fad and moves significantly when the knee straightens and bends. Sometimes scar tissue in the plica can cause anterior knee pain based upon scar tissue in the plica - read more here
Osteoarthritis in the knee means wear and damage of the cartilage. For more or less known and unknown factor the cartilage becomes thinner and in a bad quality situation. Some people seems not to be very affected until it gets really severe, while others are very troubled already when the wear situation starts. In my opinion this can be explained how the synovial tissue, that contains all the nerve endings, responds when the microscopic cartilage particles are going to be reabsorbed from the knee. For a small proportion of people, the synovial tissue will get swollen and painful already when it gets in contact with a small amount of cartilage particles and for those the symptoms of osteoarthritis will start concomitantly to the wear starts. This can be very frustrating since you cannot see the osteoarthritis in X-rays and MRI in the early phase of osteoarthritis. For most people the symptoms of osteoarthritis will first appear when the wear is more pronounced. The typically symptoms will then be pain after activity and night pain Many known and unknown risk factors for osteoarthritis exist. First of all is previous injuries such as meniscal tears, cruciate ligament tears, cartilage lesions, bowed legs and fractures of importance. Also more intrinsic factors like heritage and nutrition (D-vitamin) are of importance.
How can you prevent further degenerative changes in the knee? First of all are you going to live a healthy live and keep your weight down. You shall avoid activities that implies a lot of stresses in the same part of knee. This could for example be walking long distances or running, when the forces are applied to the same small spot in the knee for every step. Contrary to this is activities like bicycling, rowing and swimming that are much more healthy for the knee. Actually is activity of importance for bringing fresh joint fluid to the cartilage and for this is bicycling very healthy. In cases with malalignment, meaning that something in loaded in the wrong way, it can be preventive to have surgical correction of the deformity. This is the situation when you are bowlegged or when you kneecap is tracking crooked or irregular. See Tibial osteotomy or anterior knee pain
This is a little piece of cartilage that is floating in the knee. It can sometimes be caught between the condyles. It can easily be removed by an arthroscopy. It can not alway be seen on MRI´s or X-rays
Baker cyst´s or Popliteal cyst´s are liquid in the rear site of the knee Are you troubled by a Baker cyst there is about 90 % risk, that it is caused by a knee injury, such as a meniscal tear, cartilage lesion or an ACL rupture. If you are one of those without such an injury, don't let anyone remove your Baker cyst by open technique from the rear site of the knee, since there is a 60 % risk of relapse. The background for developing the cyst is a plica in the rear site of the knee, that both produce liquid and act as a valve, meaning that the liquid runs to the rear site into the cyst, but it cannot escape. If the cyst does not disappear by empty it and installing steroid, you need to have the cyst removed. For this you need to have a special arthroscopic procedure with removal of the plica in the rear site of the knee. Eventually read more here
Kneeguru have made a little paper on this - just click here
There exist many types of knee injuries and here is anterior knee pain, jumpers knee, runners knee and pes anserinus pain, some of the most common, and those could be caused by overuse.