Knee pain is not uncommon in orthopedics - millions of people in Germany suffer from it regularly. Some feel a slight pull when climbing stairs, others a dull pressure in the knee after sitting for a long time, and others experience a stabbing pain when under load. But when do these complaints indicate serious joint damage? And when is the time to consider an artificial knee joint ?

Many patients put off this question for years. They try various pain medications, physical therapy, bandages, injections, or alternative treatments - often with only short-term effects. But eventually, the question arises: "Do I need a knee replacement?" Or even a total knee replacement (TKR), which completely replaces the knee joint?

At the same time, many myths about knee replacement circulate: Some believe they are 'too young' for it. Others fear long recovery times or poor durability of the implants. Concerns about surgery also play a significant role. However, modern knee implants enable excellent results, rapid rehabilitation, and a significant improvement in quality of life.

This article answers in detail how to recognize when the time has come for an artificial knee joint. You will learn which symptoms are typical, what diagnoses doctors make, which conservative therapies are useful, how to differentiate between total joint replacement (knee TEP) and partial joint replacement (e.g. sled prosthesis) and why the choice of an experienced knee expert is crucial.

1. What does it mean to need an artificial knee joint?

When talking about an artificial knee joint , it usually refers to a total knee arthroplasty (TKA) in most cases. It replaces the damaged joint surfaces of the femur, tibia, and possibly the patella with high-quality implant components made of metal and plastic.

However, before a complete joint replacement is necessary, a partial joint replacement – especially a sledge prosthesis (unicondylar joint replacement) – can be an excellent option. This is used when only part of the knee joint (usually the inner side) is worn out. The advantage: the surgery is smaller, the patient's own cruciate ligament is preserved, and patients achieve very natural mobility.

The most common cause of an artificial knee joint is knee osteoarthritis. It develops slowly, insidiously, and often unnoticed. Initially, only the cartilage is damaged, but in advanced stages, bone rubs on bone – an extremely painful and inflammatory process.
Other causes can be malalignments, injuries, or rheumatic diseases.

2. The typical symptoms: What your knee is telling you

A healthy knee causes no pain. If complaints persist over a long period of time, this is a sign that the joint is overloaded, inflamed or already structurally damaged. Typical symptoms that may indicate that a knee replacement is necessary are:

Weight-bearing pain

Many sufferers initially only experience pain when walking, hiking or climbing stairs for a longer period. Typical is an intense pain when going downhill or when descending a staircase.

Start-up pain

If the knee hurts after sitting or resting for a long time, this is a classic sign of incipient osteoarthritis. The first steps are uncomfortable - after a short time, the complaints often improve somewhat before they become stronger again during the day.

Resting pain and nocturnal pain

This form of pain indicates that the osteoarthritis is far advanced. An inflamed joint increasingly disturbs sleep - an important warning sign.

Swelling and inflammation

Recurring effusions (water in the knee), heat or swelling are indications that the knee joint is permanently overloaded and inflamed.

Limitation of mobility

If you can no longer fully bend or straighten your knee, this indicates a structural damage in the joint. Many patients notice that they can no longer squat or have difficulty climbing stairs.

Grinding, rubbing, or locking

When bony structures rub against each other, a noticeable or audible grinding can occur. 'Blockages' in the knee can indicate that loose joint bodies or meniscal damage are present.

Altered gait pattern

Many patients start to limp, put their leg down more carefully or relieve the affected knee intuitively. This often leads to subsequent problems in the hip, back or ankle joint.

If several of these symptoms occur simultaneously and persist over a longer period, it is advisable to consult a knee specialist to have the cause professionally clarified.

3. When conservative measures are no longer sufficient

At the beginning of treatment, non-operative measures are always considered. These include:

• targeted physiotherapy
• Muscle-building training
• Anti-inflammatory medication
• Joint injections
• Braces
• optimized movement patterns
• Weight reduction

These approaches can reduce pain and slow down the progression of osteoarthritis. However, they cannot restore damaged joint surfaces. If the cartilage is completely worn away or symptoms worsen despite intensive conservative therapy, an artificial knee joint becomes a viable option.

A clear sign that conservative measures have been exhausted is the loss of quality of life: when pain dominates your daily routine, when you have to avoid certain activities or hobbies, or when you are professionally restricted, it is the right time to clearly consider a knee replacement.

4. How the doctor determines if you need an artificial knee joint

The diagnosis consists of several steps:

Medical history

The doctor discusses with you when the pain occurs, how long it lasts and how severe it is. It is also important to clarify how much your symptoms affect your daily life.

Clinical examination

The knee is examined for mobility, stability, axial alignment, swelling, and tender points.

X-ray examination

The X-ray image is the most important component of the diagnosis and shows:

• Degree of osteoarthritis
• Joint space narrowing
• Bony changes
• Misalignments
• Osteophytes

It is typical that cartilage is not visible – its wear and tear manifests itself in the joint space becoming increasingly narrower.

Supplementary MRI examinations

These are used especially when there is suspicion of meniscal damage, ligament injuries, or early stages of osteoarthritis.

Decisive is: Not the X-ray image alone decides, but the combination of imaging, symptoms, and your individual suffering.

5. The right time for an artificial knee joint

There is no "magic moment" from which a knee prosthesis is unavoidable. Rather, the right time results from several factors:

• Pain that dominates everyday life
• significantly limited mobility
• lack of effectiveness of conservative measures
• nighttime or rest pain
• severely impaired quality of life
• increasing malalignments like bowlegs

Too late an operation can lead to muscle wasting, worsening malpositions or severely limited mobility. The body gets used to harmful movement patterns that are difficult to reverse later. Therefore, the optimal time is reached when pain, functional limitations and imaging clearly indicate advanced joint destruction.

6. Knee TEP or a sled prosthesis? – The choice of the right implant

The term 'artificial knee joint' encompasses various surgical options. The two most important are:

1. Partial joint replacement (unicompartmental knee arthroplasty)

A unicompartmental knee arthroplasty is ideal when only one joint compartment (usually the inner side) is affected. Advantages:

• less invasive intervention
• faster healing process
• very natural knee movement
• preservation of the anterior cruciate ligament
• minimal bone resection

Many patients with a sled prosthesis regain mobility that is remarkably close to the natural knee.

2. Total knee replacement (TKR)

A knee TEP replaces the entire joint surface of the knee joint. It is necessary when:

• the entire joint surface is worn out
• malalignments are pronounced
• several compartments (inner, outer and kneecap joint) are affected

Modern knee prostheses today enable very good functionality, stability and resilience over many years.

An experienced knee expert can precisely determine the best option for you based on symptoms, X-rays, and clinical tests.

7. How an artificial knee joint can change your life

Patients who have suffered from pain for years often report a massive improvement shortly after the operation. Particularly impressive is the freedom from pain while walking, the regained mobility, and the ability to manage everyday tasks without difficulty.

Sports activities such as cycling, swimming, or Nordic walking are usually possible again without problems. Traveling, walking, or longer distances also become a matter of course again.

Correct: Rehabilitation requires patience, discipline and therapeutic support - but the result is worth it. Many patients say in retrospect: “I should have had the operation earlier.”

8. Why a knee specialist is so important – and why Prof. Kutzner in Mainz is an excellent choice

If you suffer from persistent knee pain, limited mobility or typical complaints of advanced knee osteoarthritis, then the choice of the treating doctor is a crucial factor for your later treatment success. An artificial knee joint, a knee prosthesis or a knee TEP are among the most complex orthopedic procedures – and require the highest technical skill, a lot of experience and a fine sense of what solution is really meaningful for the individual patient.

Why expertise makes the difference

Not every painful knee needs an immediate prosthesis. Sometimes a joint-preserving therapy is sufficient, sometimes a partial joint replacement like a unicompartmental knee arthroplasty (UKA) is the clearly better choice. An experienced knee specialist reliably recognizes these differences.

An expert:

• assesses precisely whether the arthrosis affects the entire joint or only a part,
• decides whether an artificial knee joint is really necessary,
• checks whether a minimally invasive surgical technique is useful,
• plans the alignment and positioning of the prosthesis with highest accuracy,
• accompanies rehabilitation and follow-up treatment to avoid complications and enable optimal mobility.

Especially in the field of knee arthroplasty, experience demonstrably leads to better results: less pain, faster mobilisation, lower complication rates and a long-term stable prosthesis function.

Why Prof. Dr. Karl Philipp Kutzner is an excellent choice at Endoprotheticum Rhein-Main

If you are looking for one of the leading knee specialists in Germany, it is hardly possible to bypass Prof. Dr. Karl Philipp Kutzner . He is one of the most recognized experts in knee arthroplasty, artificial knee joints, minimally invasive knee TEPs, and partial joint replacement procedures like the sliding prosthesis.

At the Endoprotheticum Rhein-Main in Mainz you can expect treatment that is consistently tailored to your individual needs - scientifically sound, technically precise and personally accompanied.

What distinguishes Prof. Kutzner:

• High specialization in knee and hip endoprosthetics
  Prof. Kutzner performs a large number of knee TEPs, sled prostheses and revision surgeries annually – a crucial quality factor.
• Latest surgical techniques
  Including minimally invasive approaches, optimized soft tissue preservation, and modern implants with high durability.
• Precise diagnostics to avoid over- or under-treatment
  Patients increasingly seek a second opinion because they are uncertain whether they really need a TKR. Prof. Kutzner is considered particularly thorough and differentiated in his decision-making.
• High patient satisfaction and individual care
  From the initial consultation to aftercare, you have a personal contact person who understands your knee - and you as a person as well.

Conclusion: Your decision for long-term quality of life

An artificial knee joint is not just an operation - it is a decision for your future. So that you can walk pain-free again, sleep better, be physically active and enjoy your daily life without restrictions, diagnosis and treatment should be in the hands of an absolute specialist.

If you want to know whether an artificial knee joint, a unicompartmental knee arthroplasty or a joint-preserving therapy is suitable for you, the Endoprotheticum Rhein-Main under the direction of Prof. Kutzner is a trustworthy and excellent contact point.