The arthrosis of the shoulder is less frequent than the arthrosis of the hip, but it is also mainly less well-known. It consists in a disappearance of the cartilage leading thus to pains and a stiffness of the shoulder that is sometimes very invalidating.
The only alternative is the replacement by a shoulder prosthesis which the surgeons of the shoulder are very well acquainted with; it is very well suited and, most of the time, makes the pains disappear and provides satisfactory mobility to achieve everyday life movements.
The most common indication is of course arthrosis, but also any very complicated fracture which cannot be repaired by material, or else a total rupture of the tendons, impossible to repair, and that can lead to total functional impotence of the patient.
A shoulder prosthesis has a longer lifespan than that of the hip, generally at least 20 years.
The shoulder joint or glenohumeral joint is a synovial joint between the head of the humerus and the glenoid cavity, strengthened by the fibro-cartilaginous ring, the glenoid ring. The joint’s capsule is reinforced by 2 or 3 ligaments. It is wide and loose on its lower part.
Most of the joint’s stability is ensured by the muscles of the head:
- The sub-scapula muscle at the front
- The supra-spinal muscle at the top
- The sub-spinal and little round muscle at the back
They are inserted into the proximal part of the humerus via their tendons which form a fibrous tissue blade difficult to separate from the joint capsule below: the head of the rotators.
Above the head, but separated from the latter by the sub-acromial purse, lies the arc constituted by the acromion (a bone structure of the scapula located just above the humeral head) and the coraco-humeral ligament.
The clinical symptoms are for most of the time pains, sometimes very acute at the least move, along with a stiffness that evolves over the months with sometimes an ankylosis leading to a total impotence of the shoulder.
This pathology can also integrate the scope of a rheumatic disease (rheumatoid polyarthritis) which can totally destroy the shoulder joint.
The X-rays that must be done are plain X-rays on which one can observe the absence of cartilage and the progressive destruction of the joint.
In some cases, it will also be necessary to realize an arthroscanner or an MRI to assess the state of the tendons and to choose a type of prosthesis.
The pains and the stiffness will increase as months pass by, with an ineffectiveness of the medical treatment.
The implantation of a prosthesis requires a skin incision of 5 to 10 cm, either on the anterior face of the shoulder, or on the external face, according to the type of prosthesis used.
The operation lasts on average an hour to an hour and a half. Most of the time, the prosthesis is impacted in the bone and re-colonized within a few months by the bone cells of the patient.
Sometimes, it is necessary to cement this prosthesis.
There are two parts to the prosthesis:
A part stuck to the scapula which is called the glenoid part.
A part set into the bone shaft called diaphyseal and metaphyseal part.
This prosthesis is made of an alloy (chromium and cobalt) and the part for the joint is in polyethylene.
An immobilization of the shoulder will be realized for a week and re-education will begin as early as the 2nd day.
They are not specific at all to the surgery of the shoulder. The anaesthetist will provide you with relevant information during the pre-operation consultation.
The main blood vessels (arteries, veins) can exceptionally be affected, which may have serious consequences; with less serious consequences, other little veins may be hurt, which will lead to a haematome of the shoulder called haemarthrosis.
Complications of the nerves:
It may be possible to have an area of skin anaesthesia round the scar and even localized itches because of small nervous ramifications under the skin being affected. Generally, these unpleasant sensations diminish with time.
It is an infection of the shoulder which requires an antibiotics treatment and often to be operated again, in order to cleanse the joint and sometimes, in the most serious cases, to take out the prosthesis.
The prosthesis may come out of its cavity through a degradation of the fitting to the bone and can cause pain. It leads to replacing the prosthesis within a few months to several years.
This complication in surgery may also occur outside of all operation gesture. It often seems to affect women over 40. Its symptoms are a decalcification of the shoulder joint along with invalidating pains. We often observe a redness of the skin, a rising of the sweating, heat, a stiffness in the joint. It requires a functional and medical treatment by easy re-education. It can also be provoked by unsuited physiotherapy. It usually disappears spontaneously. The recovery can be achieved over a few weeks but can also take up to 2 years.
The patient will stay 4 days in clinic and will then go back home and have re-education sessions.
The shoulder will be immobilized the first few days. A passive immobilization will be undertaken as early as the second day, as soon as the drains are removed. A check-up X-ray will be done on leaving the operating room.
Pain care will be shared between the anaesthetists, your surgeon and the nurses on duty.
When you leave the clinic, your surgeon will give you the prescriptions for painkillers, dressing, re-education, work-leave if necessary and your next appointment.
Of course your GP will receive an account of the operation as well as a mail explaining the therapeutic act carried out and the operating consequences to foresee.
Everyday gestures can be done at the end of the 1st month and progressively improved.
All gestures can be done without any restraint between the 3rd and the 6thmonth.
The pain will seriously decrease, even disappear totally as early as the 2ndweek.
As regards mobility, it requires a long re-education, and the final result concerning mobility will hardly be achieved before the 6th month.