As the life expectancy of the population increases, so too does the proportion of people requiring a prosthesis. The joints degenerate progressively with increasing age and the protective layer of cartilage becomes thinner and thinner. Eventually the bones then rub directly against each other. The diagnosis: joint degeneration (arthritis). Pain increases and mobility is limited and painful, and is later almost no longer possible at all. Millions of people are affected. A joint can also become severely damaged due to an accident, rheumatism, an infection or previous surgery.

Fundamentally, all large and small body joints can be affected. Because we walk in an upright position our hip and knee joints experience the most load. Day in and day out, year on year, they are subjected to countless rotations and jolts.

Conservative methods such as physiotherapy are always the first step in trying to manage the problem. If the wear and tear on the joint is however far advanced and the quality of life affected, implantation of an artificial joint (endoprosthesis) is possible.

Endoprostheses have been used for more than a hundred years. They have been a success since the 1960s, thanks to improved implants and standards.

A properly implanted endoprosthesis allows you to live a normal life and engage in physical activity. Keys to the success of the procedure are the selection of an advanced, high-quality implant, a sophisticated and gentle surgery technique and the experience of the surgeon.

Our role in this is to provide our patients with professional advice. Depending on your symptoms and existing findings we design the best possible therapy for you. Our goal is not only for you to be pain-free, but also for you to regain your mobility! So that you can once again enjoy quality of life!

An essential prerequisite for a high success rate is a maximum level of hygiene so as to avoid the dreaded complications – infections. For this reason, the surgeons in our department wear stringently sterile surgical helmets when performing joint replacement surgery.

We attach particular importance to the minimally invasive Yale technique for the implantation of hip replacements in our operative therapy.

We also offer total joint revision surgery. As a result of the large number of procedures performed and the wide range of service offered, our department of orthopaedics/joint replacement at the Wolfart Clinic has been certified as a maximum care arthroplasty centre.

We hope that you are happy with the treatment provided by us and that you will return home healthy.

HIP (Yale technique)

Yale technique

The Yale technique is a particularly gentle surgery method for implanting artificial hip joints. We have been using this minimally invasive procedure since 2003 and have to date performed over 8000 hip replacements in our department using this approach.

This surgery method developed by Dr. Jack Irving (Yale University, USA) involves 2 small incisions of approx. 6-8 cm long for the implantation of a hip prosthesis. One incision is made on the front of the hip joint and the other on the back, whereby the length may vary depending on anatomical factors. Surgery is performed via naturally created gaps in the muscle. This means: We do not cut through any muscle groups that are important for the hip function, but rather gently move the muscles aside to insert the new hip joint. The surgeon still has a good view of the operating area, however. The skin incisions are made in such a way that the operating area is perfectly visible – both the socket and the shaft of the femur. The implants can thus be inserted extremely accurately.


The Yale technique has distinct benefits for the patient: Since only tiny incisions are made and no muscles are injured, the patient is mobile again a lot sooner. The muscles surrounding the hip joint are fully functional immediately after surgery. Less pain is experienced and blood loss can be minimised.

Even on the day of surgery the patient can generally put full load on the leg. Walking with the new joint begins on the operative day; crutches are only used for improved stability.

Various prosthesis models
Projection of the prosthesis on an anatomical preparation
Osteoarthritis of the right hip
Pelvic view with prosthesis planning
After implantation of a cement-free hip replacement

Revision surgery

In the last few years we have also increasingly been using the Yale technique for hip replacement revision surgery. Even with these complex procedures, the hip muscles can be better protected than with conventional procedures.

The efficacy of the Yale technique has also been shown in a comparative gait analysis study (pdf Download).

To find out how a joint replacement procedure is performed please click here.



An artificial knee joint can be a good alternative in case of severe knee pain and limited mobility, especially if the layer of cartilage is already severely worn away, conservative measures are no longer proving successful and joint-preserving surgery is also no longer an option.

As part of the examination at OrthoPraxis, we determine which parts of the knee joint are damaged and what the condition of the capsular ligaments is in each case. Based on that we then select the implant to be used.

Partial knee replacement (unicondylar) or total knee replacement (bicondylar) is available, whereby the worn part of the cartilage is replaced with a new surface. The unicondylar procedure is performed if only one part of the knee joint needs to be artificially replaced and the other parts are still in a good condition. The bicondylar procedure is performed if several sections of the knee joint are arthritic. The entire joint surface is replaced in this case.

Thanks to a bone-conserving surgery technique, we are able to preserve the capsular ligaments in the knee. The artificial surfaces are designed in a way that closely resembles their real-life counterpart. This means the patient can generally move extremely freely with the artificial knee joint. Participating in sports is also possible. We will gladly advise you as to which sports are suitable for you.

Knee joint replacements today are extremely long-lasting: Follow-up examinations after 15 years have shown that 90% of implants still function very well.

If the ligaments in the knee joint no longer function properly prior to surgery, so-called rotating-hinge and fixed-hinge knee implants are also an option in rare cases to compensate for this deficiency.

In some cases, patella posterior surface replacement is also necessary.

We are happy to advise you – in detail and on a personalised basis.

Bicondylar prosthesis with rotating bearing
Projection of the prosthesis on an anatomical preparation
Knee after implantation
of a bicondylar prosthesis
Knee joint with osteoarthritis
Gait analysis with pressure distribution after surface prosthesis
Movement cycle with surface prosthesis and additional patella posterior surface replacement

To find out how a joint replacement procedure is performed please click here.



Advanced arthritis (degeneration) of the shoulder joint may require implantation of an artificial joint. Severe cartilage damage of this nature occurs not only as a result of excessive load with advancing age, but often also after the bone has healed after a complicated fracture. An artificial shoulder joint may also be necessary in the case of irreparable multi-fragment fractures (see Fig.).

A shoulder endoprosthesis, also known as a shoulder prosthesis, is modelled on the real-life shoulder joint. Either the humeral head or the shoulder socket can be replaced – or both.

Implant selection depends on the function of the muscles surrounding the shoulder joint. These muscles, the so-called rotator cuff, move and stabilise the shoulder joint. If the joint surface is damaged due to arthritis or a multi-fragment fracture but the rotator cuff is still intact, we only need to replace the surface of the humeral head. In certain cases it may be necessary to resurface the shoulder socket (glenoid) with polyethylene.

In the case of arthritis, the cartilage
of the humeral head is worn away.
After implantation of an artificial joint
Multi-fragment fracture of the humeral head
Recovery after severe shoulder joint arthritis
After implantation of a shoulder joint replacement

Reverse shoulder replacement (also known as Delta prosthesis)

If the rotator cuff is stretched to the extent that it can no longer be reconstructed, this is referred to as cuff tear arthropathy. Patients affected by this condition suffer from severely reduced range of motion of the shoulder. They are no longer able to lift the arm, or only with severe pain. The humeral head moves upwards and under the roof of the shoulder thereby preventing normal function.

In this case too, we first try to improve the function of the shoulder and relieve the pain with conservative measures such as physiotherapy. If this does not lead to the desired success, the function of the shoulder can be restored in these cases by means of reverse shoulder replacement – also known as Delta prosthesis.

Reverse shoulder replacement involves reversing the normal relationship between the shoulder joint components: A socket is placed on the side where the humeral head is naturally located, and a metal hemisphere that resembles the humeral head is attached where the socket is found in normal anatomy. The reason reverse prosthesis is suitable for patients with a destroyed rotator cuff is that the centre of rotation of the shoulder moves downwards and closer to the body. This means you need only rely on one muscle for the prosthesis to function – the deltoid muscle. The shoulder then has normal range of motion again, without any pain.

X-ray of reverse (Delta) shoulder replacement
Left: Image of a cuff tear arthropathy; the humeral head moves upwards under the roof of the shoulder.

Right: By reversing the head/socket principle, the humeral head is kept down, allowing other muscles (deltoid muscle) to take over the function.

Diagram of the implants
After implantation

We will gladly advise you in detail as to whether shoulder joint replacement is a suitable option for you and if so, which implant would work best for you.

To find out how a joint replacement procedure is performed please click here.

Revision surgery

Modern prostheses today are extremely long-lasting – in an ideal situation often 15 to 20 years. Thereafter, the artificial joint can be replaced by a new one. Medical professionals call this procedure “revision surgery”.

There are various possible reasons for revision surgery: The main reason, without a doubt, is material degeneration. After all, the prosthesis is subjected to substantial loading during everyday life. But aseptic loosening, accidents involving fractures, or infections in some cases are also contributing factors. This occasionally leads to situations where an artificial joint must be replaced relatively early on.

Depending on the individual case, special revision implants are available for revision surgery. Even in really difficult circumstances stable fixation of the new implant is possible. Bone graft substitutes are also used. This means you will have a customised, strong joint replacement allowing you to finally move freely again, without any pain!

Revision surgery is becoming ever more important in our specialised joint replacement unit: implant replacements already make up almost 20% of all procedures performed.


X-ray of socket loosening
X-ray taken after revision surgery using an acetabular ring
12 years after revision hip replacement surgery
12 years after revision hip replacement surgery


Dislocation of the knee after total knee replacement due to material wear
X-ray taken after revision knee replacement surgery

To find out how a joint replacement procedure is performed please click here.

Corona Information
Corona Information