Why replace the knee joint?
KNEE REPLACEMENT
Why replace the knee joint?
A normally functioning knee joint has smooth and somewhat elastic cartilage surfaces that glide freely across one another with minimal friction, and allow for normal and pain free movement. Abnormal cartilage wear is called osteoarthritis. Progressive deterioration of the cartilage causes the bones to come into direct contact, leading to deformities, pain and infection.
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If non-surgical treatment (physiotherapy, kinesitherapy, analgesic and anti-inflammatory medication) does not adequately alleviate the problem, the knee joint must be replaced by a prosthesis.
Why replace the knee joint?
What is a knee prosthesis?
A normally functioning knee joint has smooth and somewhat elastic cartilage surfaces that glide freely across one another with minimal friction, and allow for normal and pain free movement. Abnormal cartilage wear is called osteoarthritis. Progressive deterioration of the cartilage causes the bones to come into direct contact, leading to deformities, pain and infection.
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If non-surgical treatment (physiotherapy, kinesitherapy, analgesic and anti-inflammatory medication) does not adequately alleviate the problem, the knee joint must be replaced by a prosthesis.
The prosthesis is designed to mimic the functioning of a normal knee joint as well as possible. Part of it is mounted on the femur or thigh bone, the other part covers the top of the tibia or shinbone. In most cases it also includes a prosthetic kneecap. The materials used are polyethylene and cobalt-chrome alloys. These are chosen for their longevity and the fact that they are generally well adopted by the human body, with minimal chance of infection.
Dr. Van den Wyngaert is one of only a few doctors who use a patended, ultra-precise measuring and prosthesis placement tool that minimizes the chance of damaging your healthy tissue.
Je tijdschema in een notendop:
EEN KNIE PROTHESE
Je tijdschema in een notendop
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investeer 3 maanden in je gehele revalidatie
Dag -1 ; de dag voor je operatie zal je worden gecontacteerd door de opnamedienst wanneer je aanwezig moet zijn in het ziekenhuis de dag van je ingreep
Dag 0; de ingreep duurt een 45-tal minuten , je bent onder narcose voor 50 minuten gemiddeld. De wonde is een 10cm lang aan de binnenzijde van je knie. Met robotchirurgie heb je nog twee kleine steekwondjes aan je onderbeen waar de navigatie-trackers werden geplaatst.
Dag 1-2; ben je opgenomen in het ziekenhuis. De dag na je ingreep mag (moet) je de geopereerde knie volledig belasten. Je gaat onder leiding van de kinesisten je knie belasten en stappen met 2 krukken.Voor je naar huis gaan we je ook leren hoe je veilig de trap kan doen.
Een grote groep mensen kunnen reeds na 48h het ziekenhuis verlaten, iedereen kan naar huis binnen de 3 overnachtingen na je ingreep.
Dag 3-14; Je mag volledig belasten op je geopereerde knie. Veel mensen stappen al vlot met 1 kruk (en zelfs zonder krukken) thuis na 1 week. Je kan je laten bijstaan door je kinesist. Eventueel zelfs in combinatie met de Move-up app
Dag 14-16; verwijderen van de hechtingen bij de huisarts (ook best een bloedname controle)
Week 3-4; een grote groep kunnen met de wagen zelfstandig rijden. Dit kan je veilig doen indien je vlot de trap op/af kan (met de leuning).Bespreek het ook met je kinesist. Veel mensen wachten tot 6 weken na de operatie bij de controle.
Week 6; controle bij dr Van den Wyngaert met belaste radiografische opname van de geopereerde knie. Vanaf dan volledig stappen zonder hulp van krukken. Ongeveer 8 op 10 van de geopereerde mensen komen al naar de consultatie zonder hun kruk.
Week 6 en later; de vlotheid van je verdere revalidatie hangt vooral af van de snelheid dat je knie ontzwelt. Fietsen en wandelen kan afhankelijk van de zwelling.
Vanaf dan progressief al je vroegere activiteiten terug opnemen.
1 jaar na je ingreep ; best nog eens een controle voorzien met een controle radiografie van de knie
What is a knee prosthesis?
The prosthesis is designed to mimic the functioning of a normal knee joint as well as possible. Part of it is mounted on the femur or thigh bone, the other part covers the top of the tibia or shinbone. In most cases it also includes a prosthetic kneecap. The materials used are polyethylene and cobalt-chrome alloys. These are chosen for their longevity and the fact that they are generally well adopted by the human body, with minimal chance of infection.
Dr. Van den Wyngaert is one of only a few doctors who use a patended, ultra-precise measuring and prosthesis placement tool that minimizes the chance of damaging your healthy tissue.
Total vs. partial knee replacement
Ook in de geneeskunde zijn er steeds belangrijke technische evoluties om zo nog betere en betrouwbare resultaten te kunnen bekomen met onze patiënten.
Robot geassisteerde (knie) chirurgie is daar een recent voorbeeld van.
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Deze technologie geeft kniechirurgen nog nauwkeurigere instrumenten om met toenemende precisie en accuraatheid knieprothesen te plaatsen dan de huidige conventionele technieken.
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In het AZ ALMA ziekenhuis zijn we als groep kniechirurgen (Dr Van den Wyngaert, Dr Ghijselings,Dr Demurie,Dr Van Onsem) bij de eersten in Europa om robot geassisteerde knieprothese chirurgie (Mako-robot) uit te voeren met de de gedigitaliseerde robot-arm geassisteerde chirurgie.
Met deze hoog technologische en minder invasieve chirurgie kan nauwkeuriger geopereerd worden in moeilijk bereikbare zones van het menselijk lichaam dan met klassieke conventionelere technieken.
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Voordat je een knie-prothese ingreep krijgt met deze robot geassisteerde technologie dient wel een scan opname (CT-scan) van de zieke knie te worden genomen op de dienst radiologie.Dat kan tot 1 week voor de ingreep.
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Total vs. partial knee replacement
If osteoarthritis affects only one of the three knee chambers, a partial knee prosthesis could be advised, meaning only part of the knee joint is replaced - as opposed to a total knee replacement. There are three types: a medial unicondylar knee prosthesis replaces the inner knee chamber, a lateral unicondylar prosthesis replaces the outer chamber, and a patellofemoral prosthesis replaces the kneecap.
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Partial knee prosthesis has some clear advantages: rehabilitation tends to proceed faster, as the procedure is less invasive; patients report the return of a normal physiological feeling sooner after surgery; and if necessary, a partial prosthesis can easily be rebuilt into a total prosthesis. The best option is thoroughly researched and discussed on a case by case basis.
Dr. Van den Wyngaerts unique care program
Together with his colleagues, dr. Van den Wyngaert has perfected a unique care program for knee replacement, specially designed to minimize the risk of collateral damage to the knee muscles and ligaments. This allows a faster and less painful recovery than more common operation techniques.
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The short hospitalization period (usually 1 to 4 days) implies a multidisciplinary approach. Everyone involved in your rehabilitation works together within the same treatment philosophy: surgeon, physiotherapist, kinesitherapist, ergotherapist, nurses, social service and orthopedic technician.
How long does a prosthetic knee last?
The average lifespan of a knee prosthesis depends on the criteria used to determine its "demise". If we consider the need for revision surgery (placement of a new prosthesis) as a failure of the original prosthesis, the "survival rate" is still 95% after 10 years. In other words, only 5 out of 100 patients need a new prosthesis ten years after their surgery.
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After twenty years, the survival rate of the prostheses is still 86%. Mind you, we are talking about knee surgeries that were performed twenty years ago. Operation techniques and the prostheses themselves have evolved throughout the years, making it likely that recent knee prostheses will last even longer.
During surgery, dr. Van den Wyngaert tests the stability of your knee joint and the quality of your ligaments. Next he makes two or three small incisions through which the arthroscope, a camera at the end of a tube only 5 mm in diameter, is inserted. It sends live images from inside your knee to a monitor. If you want, you can follow the proceedings this way.
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Depending on the condition of your knee joint, the whole procedure takes just 15 to 30 minutes. Dr. Van den Wyngaert immediately treats any damaged components. Any loose fragments in the cartilage and/or the meniscus are removed and course surfaces can be polished. A ruptured meniscus can be stitched immediately and the quality of your cruciate ligaments is also evaluated.
Did you know?
The lifespan of all prostheses is entered in so-called implant registers. These databases are an interesting source for evaluating the evolution of knee replacement surgery and its success rate. The Belgian implant register is called Orthopride. Every orthopedic surgeon in the country is required to register all replaced knee joints.
When we analyze the data, some trends become apparent - besides the excellent long-term results of knee replacement surgery. Due to the increase in average population age, the yearly number of knee replacements is on the rise, but especially striking is the ever growing proportion of younger patients (below 50).
In the age group below 65, the risk of failure of the knee prosthesis appears to be significantly higher than for older patients. The fastest rising patient group for revision surgery is even younger - 60 and under. More specifically, patients between the ages of 50 and 55 have the highest chance of prosthesis failure in the short term, especially men.
That's why the decision to undergo knee replacement surgery needs to be considered very carefully. Especially because knee replacement, though a routine operation with generally excellent results, is a "terminal" procedure, meaning revision surgery in case of failure does not necessarily guarantee a better result than the original procedure.
Below is an overview of the 1-year and 7-year survival rate of knee prostheses in the Netherlands (from the 2015 LROI register): https://www.lroi.nl/downloads/7/lroi-jaarrapportage-2015.pdf
What's the price of knee replacement surgery?
Dr. Van den Wyngaert is not bound by conventional rates and may legally charge a free rate for consultations. In most cases, a consultation costs around 45 euro (2018).
This fee supplement only applies to consultations. For the surgery itself, the hospital always charges the convention rate. More details about the cost of knee replacement surgery can be found on the AZ Alma website.
Orthopedic surgeon - specialized in the treatment of knee injuries