Shoulder prostheses | Artificial shoulder joint
Shoulder prostheses | Personalised prostheses | Surgery | Risks and complications | Costs | Consultation
Before a major operation is planned, the joint must be examined by a shoulder specialist; the investigations are usually made with X-ray and MRI. Based on the results, your doctor will discuss the situation with you and show the possible solutions. Conservative measures without surgery can often be helpful for a time. Only when these measures have been exhausted and the suffering remains is there an indication for joint replacement surgery.
Anyone who has had long-term pain knows how much of a burden this can be. The arm cannot be moved, everyday activities are restricted and there is a frequent need for pain relievers, which have side effects. The primary success of shoulder prostheses has been to stop these chronic pains in the majority of patients. This alone gives a wholly new quality of life. In addition, the functionality of the arm is improved in nearly every case. It certainly does not worsen. When you can dress yourself again, eat without making stains and take the walking stick just in case the shoulder hurts, you notice the impressive gains.
Shoulder prostheses have developed rapidly since the 1980s. There are therefore many different products on the market, some of which are similar and some completely different. In principle there are two types of shoulder prostheses.
- Anatomic prostheses: So-called as they copy the natural anatomy of the shoulder joint. This means that a metallic head of the same size is where the head of the humerus used to be; this is anchored into the bone via a shaft. Where the glenoid cavity used to be is now a joint socket made of a special polyethylene. This prosthesis has the great advantage that the mobility of the shoulder joint is completely restored and is suitable for even highly demanding activities. This prosthesis allows sport to be played, occasionally even tennis. One study showed that golfers were able to drive further after prosthesis surgery than before the operation. The disadvantage is that this prosthesis is reliant on the perfect functioning of the rotator cuff. If this is not the case, or if the function of the musculature decreases over time, whereby the prosthesis cannot develop its functionality - or loses it - the arm can no longer be used adequately.
- The inverse prosthesis: In the 1980s, after intense study of anatomy and biomechanics, Frenchman Paul Grammont developed the concept of a prosthesis which would work even without a functioning rotator cuff. The prototype was named the "Trumpet" and eight of these were implanted in 1986 and 1987. With success: previously immobile shoulders could once again raise the arm.
The excellent performance was derived not from copying the anatomy of the shoulder joint, but its function. This occurred through an inversion of the components. A hemisphere is implanted where the glenoid cavity had once been and a socket is anchored where the head of the humerus had been. Because this socket is significantly deeper and has a smaller diameter than the original glenoid cavity, it provides greater stability and is thus not reliant on the rotator cuff. The head of the humerus is now moved by the deltoid muscle alone. The Delta prosthesis was created.
The main advantage of this prosthesis is therefore that it also functions in severely damaged or degraded shoulders. The price paid for this is somewhat decreased mobility of the shoulder joint, particularly movements above the head and behind the back.
As stated at the beginning, the question of which prosthesis is best for you is dependent on the condition and function of your shoulder.
No. The individual implants vary greatly and prostheses are manufactured with components that can be combined. This ensures the anatomy is always copied as well as possible to allow a functioning and fitting prosthesis to be implanted in every case.
Before implantation of a prosthesis, the bone anatomy of the shoulder is precisely reconstructed in three-dimensions using computed tomography; the prosthesis components are tested individually in detail until the best combination is found. This ensures the best possible result.
Shoulder prosthesis surgery usually lasts around 2 hours. The duration of the operation is dependent on the circumstances found in the surgery for the specific patient. The procedure is well standardised and without complications in nearly all cases. The patient recovers quickly after the procedure: shoulder surgery is not particularly stressful for the body.
HOW LONG IS THE STAY IN THE CLINIC?
The arm can already be used for light tasks after only 1–2 days. Patients usually stay in the hospital for around 5 days, depending on how rapidly they recover and the pain. The surgery is not very painful. Nonetheless, we often administer a pain catheter to promote rapid mobility post-operatively.
WHAT IS THE PROCEDURE FOR A SHOULDER REPLACEMENT?
The operation on the shoulder is highly standardised, which helps to avoid errors. Good pre-operative planning is important: this defines the different bone sections and implant sizes. These planning data are constantly reviewed and confirmed during the surgery.
Access to the shoulder joint is made from the front of the shoulder as there is a layer here between two muscles where no nerves run. This protects the joint. One muscle must be detached at a deep level; this is reattached at the end of surgery.
The important axillary nerve is identified in order to protect it. Growths and scarring, which often occur in osteoarthritis, are then detached and the joint revealed. As an initial step, the head of the humerus is removed and the bed for the prosthesis prepared. The remainder of the cartilage is removed from the glenoid cavity and, depending on the type of prosthesis, a new socket or ball is implanted. Finally, the corresponding counterpart is inserted into the head of the humerus in such a way that it need not be cemented in place. Test components are now inserted to test the function of the joint. Only when everything is correct are the definitive implants put in place. Lastly, the anterior muscles and skin are sutured. There may be immobilisation for a few days as this helps against any pain.
HOW CAN I PREPARE MYSELF FOR THE SURGERY?
Musculature and mobility:
It is helpful if you have as good musculature at the shoulder girdle and as good mobility of the joint as possible before the operation. Both help you considerably during the post-operative rehabilitation. Joints with especially poor mobility risk post-operative shoulder stiffness (thankfully, this is not common for prostheses). The physiotherapist will devise a programme with you that you can carry out at home to help you maintain strength and mobility.
It is very important not to have infiltrations into the joint at least 4 months before surgery. Otherwise there is a significantly increased risk of joint infection associated with a prosthesis operation.
A strong and healthy immune system helps to minimise surgery-related complications. Well-tolerated dietary supplements help in this regard, as do a healthy lifestyle, sufficient sleep and adequate exercise outdoors.
To minimise the risk of infection associated with the operation even further, we recommend you wash with a special disinfectant the night before surgery.
Before each operation it is important to have your GP make the necessary pre-operative investigations. They will pass this information to the anaesthetist and surgeon so they are well informed of your condition.
Infections of artificial joints can be triggered by standard oral bacteria. We therefore recommend that you visit a dentist before prosthesis surgery to have your teeth cleaned, if necessary. A visit to a dental hygienist is also recommended. After the operation, however, you should not undergo any dental (hygiene) procedures for at least 3 months in order to protect the prosthesis.
WHICH ANAESTHETIC IS USED?
A general anaesthetic is the most sensible solution for this surgery. A catheter for managing the pain after the operation can be inserted at the same time.
Avoidance of complications is the highest priority of orthopaedic procedures. Shoulder operations are therefore highly standardised so that it is known at any point what the next step is and in which anatomical environment the surgeon currently is. Structures that need to be protected (e.g. the axillary nerve) are imaged in advance so that their anatomy is fully visible. However, each surgery and every patient is unique. A good surgeon must therefore be well prepared, but also able to respond to the unforeseen.
General risks are present in any operation and include: Infections, wound-healing disorders, bruising and subsequent bleeding. There are shoulder-specific risks arising from the complex anatomy as the nerves and vessels for the arm are very close. You could theoretically suffer an injury, but this is thankfully the rare exception. The muscles at the shoulder are also strained during the operation, but recover quickly. Correct placement of the individual prosthesis components is important; this is not always simple owing to the anatomy and visibility. Restricted movement can result if they are not placed precisely. Very rarely, the bone that is intended to bear the prosthesis can fracture during implantation. The joint is usually stiff and immobile in the first weeks after prosthesis surgery. However, it recovers quickly with physiotherapy. Luckily, pain is not an issue in the overwhelming majority of patients.
After surgery, most patients recover so rapidly and well that rehabilitation with hospitalisation is rarely needed. As your ability to walk is maintained and the arm can soon be used again for everyday activities, you will only suffer minimal restrictions even at home.
As the inverse prosthesis changes the anatomy of the shoulder joint, the external appearance also sometimes changes slightly. The shoulder is narrower and therefore appears to be dropping.
HOW LONG DOES A SHOULDER PROSTHESIS LAST?
The prostheses implanted by Paul Grammont lasted up to 15 years. As modern prostheses are constantly undergoing improvements and we now work with newer types of implants, the service life of the prostheses is not always investigated. However, all recent studies show that the durability rate is greater than 90% after 10 years. An older study by Prof. L. Favard showed weakening of the deltoid muscle after 7–10 years. The result most likely occurred owing to the older types of prostheses used, which pulled strongly on the muscles. Modern implants no longer do this. Principally the fixation of the joint socket can loosen over time for the anatomic prostheses: this is the limiting factor. For certain prostheses there can also be degradation of the bone around the implant. However, there are no consequences from this in most cases.
One major hazard for the prostheses is a fall on the shoulder: this can not only dislocate the shoulder but could also lead to fractures around the prosthesis. These are challenging to treat and usually require a further operation.
The risks associated with an initial operation are small. The risks increase for repeated operations or for patients who have had previous surgery.
There is a lifelong risk of an infection of the prosthesis, e.g. in connection with a tooth infection or pneumonia. Recipients of prostheses must therefore take special precautions against infections. Inform your doctor or dentist that you have a prosthesis. An infection of an artificial joint is not only very difficult to treat, but often requires removal of the joint and replacement with a new one, when possible. These major revision surgeries are difficult and stressful, requiring special expertise.
The costs of a shoulder operation depend on various factors apart from the implant, such as the duration and complexity of the procedure and the length of the hospitalisation. Health insurance usually reimburses all costs if you have the appropriate insurance coverage. For the Pyramid Clinic you will require private or semi-private supplementary insurance.
As shown above, subsequent rehabilitation is only rarely needed. Simple physiotherapy is sufficient. Both are reimbursed by health insurance.
If you wish to finance the operation yourself, we will provide you with a quote on request following a comprehensive examination. This also applies especially to patients from abroad.
Our doctors have extensive experience and expertise in joint and sport surgery. Dr. med. Gregor Szöllösy is a certified shoulder and elbow expert with extensive know-how in the area of artificial shoulder joints. He is also a lecturer on the Basel Elbow Surgery Course.