The laying of a shoulder prosthesis results in the vast majority of cases to a benefit for the patient, indolence and improvement of the function.
Sometimes unfortunately the consequences are not simple, stiffness long to recover, persistence of pain but there are also complications that can lead to reinterventions:
Germs present on the skin come in contact with the prosthesis and swarm afterwards.
Depending on the aggressive nature of the germ, the external signs of infection will be early or delayed
– Early (a few days to weeks):
Inflammation of the scar, swelling of the operated area, abnormal flow and abundant see reopening of the scar. Fever is not obligatory (especially if a discharge exists) although it can be important with chills.
The blood test found signs of infection including increased white blood cells (leukocytosis) and a significant increase in CRP (C-reactive protein inflammation).
It is most often staphylococci (golden or even white) normally present on the skin (and non-aggressive) which are found in contact with the prosthesis. This environment is not natural and virgin other bacteria they reproduce in large numbers.
– Late (a few weeks to months):
The evolution can be quite normal in terms of healing (or delay in healing, long inflammatory scar) and a prosthesis that works properly.
Obviously a pain that settles or persists is a sign to watch.
There may be a progressive swelling around the scar or around the prosthesis that may progress to a productive fistula (hole with flow) sometimes at a distance from the scar (axillary trough, for example).
The germs involved are said to be less aggressive because they cause a progressive infection and often not very symptomatic (absence of fever, blood taken little disturbed or even normal) and especially the documentation of the infection is sometimes very difficult even in case of deep samples during a reintervention . It is often white staphylococci or propionibacterium (acnes in particular).
Prevention:
This risk is made minimal (but not zero) by asepsis protocols before and during the procedure and by antibiotic prophylaxis administered just before the incision (dose of preventive antibiotic).
The state of the skin locally is also important and studied until the day of the intervention (intervention sometimes postponed if a oozing lesion is found not far from the future incision).
Totally different from the first mode of contamination, it is actually an infection related to the passage of germs in the blood (bacteremia) or an infection that has reached the blood (sepsis).
The foreign body effect is important because it tends to ‘attract’ the germs to the prosthesis
That is to say if the prevention of serious infections (pulmonary, urinary, dental or ENT, digestive etc …) is fundamental and their treatment must be early and adapted.
Prevention:
The search for latent (non-active) infectious foci is systematic in order to take the time to treat them before implantation of a prosthesis in the context of the preoperative bila.
The presence of a prosthesis complicates the situation enormously compared to an identical infection without foreign body.
Indeed not only such a foreign body attracts germs but also holds them !!!
Some germs also use fireworks to resist treatments (antibiotics, washing etc …) as the ‘slime’ film that covers the walls of a prosthesis and makes them difficult to dislodge.
Start a blind antibiotic treatment, without sampling likely to recognize it and test active and effective antibiotics.
Just make ‘surface’ samples that are not very specific because the skin is covered with germs. These are often performed in the city but should not be the sole basis of documentation and therefore even if they are positive they should not allow the start of antibiotic treatment (except life-threatening infection as a risk close to sepsis).
Consult without delay your surgeon, failing this through the emergency service if there is one, refuse to take antibiotics without his agreement (EXCEPT EMERGENCY ACCORDING TO GENERAL CONDITION).
A surface infection may exist (small collection under the scar) but it communicates with the prosthesis until proven otherwise!
In case of very shy signs of infection a puncture is often performed (by your surgeon or a radiologist) under aseptic conditions identical to a surgical unit. These punctures are the first deep samples possible and reliable … The others are made during a reoperation.
The future of such a prosthesis is uncertain, because of the explanations given above.
Unfortunately, the patient does not escape a reintervention during which the prosthesis will be washed or replaced (either in an operating time or in 2 operating times) and especially to a heavy and prolonged antibiotic treatment
One can hope to keep the initial implants (at least the sealed parts) of the prosthesis under very precise conditions and often for early infections. The surgeon will assess whether such a procedure is likely to treat the infection effectively and definitely.
The procedure starts with bacteriological samples even if punctures have been performed before, then removal of the prosthesis Thorough and rigorous cleaning of the operative parts and the environment of the prosthesis then reimplantation of a new prosthesis (often strictly identical to the previous with sterile implants) using surgical and surgical instruments changed and clean.
Advantage: security against infection
Disadvantage: 2 interventions therefore 2 anesthesia, the functional result decreases in general after each intervention …
It is started immediately after performing intraoperative bacteriological specimens. Antibiotics (most often two) are changed if necessary once the known germ and its sensitivity or if they are not supported by the patient (intolerance or allergy). It is often prolonged several weeks or even months in large doses.
The antibiotic strategy is the result of a consultation between the surgeon, the anesthesiologist and a competent infectiologist in osteo-articular infections.
It is only at a distance from stopping antibiotics that we can estimate whether the infection is cured +++
In the sites of a shoulder prosthesis, instability of the prosthesis may occur.
It imposes a reduction in urgency under general anesthesia, an evaluation of its stability once reduced and finally a phase of rest or immobilization to allow the healing of the tissues distended or torn around the prosthesis.
In case of recurrence, a morphological study of the prosthesis (exact positioning), a study of the bone or muscle nerves can be proposed before considering a re-intervention aiming to modify partially or totally the prosthesis.
