Joint prostheses improve the functional capacity of patients with joint pain. In Spain, around 40,000 joint prostheses are implanted every year, mostly knee and hip prostheses, and worldwide they exceed one million. New implants and the progressive aging of the population have led to an exponential increase in the number of patients undergoing surgery, issue .

Mobilization of the implant and infection are the main complications. A high issue of infected patients lose their arthroplasty and have to undergo multiple interventions and prolonged antibiotic therapy.

The fees of infection is around 1.5% in hip prostheses and 2.5% in knee prostheses, while in revision arthroplasties these figures double, reaching 3.2% in hip prostheses and 5.6% in knee prostheses.

Infection carries a high morbidity and also a mortality rate between 2 and 7% in patients over 80 years of age. The additional expense of an infected prosthesis has been quantified at more than 60,000 euros, almost 10 times the cost of a primary prosthesis.

A higher incidence of infections has been associated with rheumatoid arthritis, skin ulcers, previous surgical interventions, concomitant urinary tract infections, use of corticosteroids, among others. Obesity is another important factor. The most frequent causative microorganisms are Staphylococcus aureus, Staphylococcus epidermidis and streptococcus.

The vast majority of prosthetic infections require a combined medical and surgical treatment with tissue cleaning and debridement with removal of the prosthesis and antibiotic therapy until any sign of infection is eradicated. Intraoperative lavage and removal of dead tissues are also required.

Early post-surgical infections are distinguished when they appear during the first month after implant surgery with predominance of local inflammatory signs, cellulitis and purulent secretion from the surgical wound. It is manifested with joint pain and not very high fever with chills. Late chronic infection occurs from the second month after surgery, with predominance of orthopedic symptoms over symptoms of infection and often with prosthetic loosening. They can manifest months or years after surgery, despite being a consequence of it. For this reason, their symptomatology is larval and the differential diagnosis with aseptic loosening is difficult to establish, with pain being their main symptom.

In chronic infections, after removal of the prosthesis, a new prosthesis is placed, in one or two stages, according to the schools, although two-stage surgery is the most commonly used. Two-stage prosthesis replacement includes initial removal of the prosthesis, placement of a cement spacer impregnated with antibiotics, antibiotic therapy and then removal of the spacer and placement of a new prosthesis. The healing rate is close to 90%.