Abstract
The two-staged exchange for periprosthetic joint infection (PJI) has become the “gold standard” worldwide. Based on the first implementation of mixing antibiotics into bone cement by Prof. Buchholz in the 70's, the ENDO-Klinik followed a distinct one-staged exchange for PJI in over 85% of all our infected cases until today. Looking carefully at current literature and guidelines for the PJI treatment, there is no clear evidence, that a two-staged procedure has a clearly higher success rate than a one-staged approach. Although postulated in relevant articles, most recommendations, e.g. duration of antibiotics, static vs. mobile spacer, interval of spacer retention, cemented vs. uncemented implant fixation, are based on level IV to III evidence studies or expert opinions, rather than on prospective randomised or comparative data.
Potentially a cemented one-stage exchange offers certain advantages, as mainly based on need for only one operative procedure, reduced antibiotics & hospitalization time and reduced relative overall costs. In order to fulfill a one-staged approach with the above described potential success, there are obligatory pre-, peri- and post-operative details, which need to be meticulously respected. The absolute mandatory infrastructural requirement is based on the clear evidence of the bacteria in combination with a distinct patient specific plan, by an experienced microbiologist, for the topical antibiotics in the bone cement with combined systemic antibiotics.
Mandatory pre-operative diagnostic testing is based on the joint aspiration with an exact identification of the bacteria. The presence of a positive bacterial culture and respective antibiogramm is essential, to specify the antibiotics loaded to the bone cement, which allows a high topical antibiotic elution directly at the surgical site. A specific treatment plan is generated by a microbiologist. Contraindications for a one-staged exchange include: failure of > 2 previous one-staged procedures, infection spreading to the nerve-vessel bundle, unclear pre-operative bacteria specification, unavailability of appropriate antibiotics, high antibiotic resistance.
The surgical success relies not only on the complete removal of all preexisting hardware material (including cement and restrictors), furthermore an aggressive and complete debridement of any infected soft tissues and bone material is needed. Mixing antibiotics to the cement needs to fulfill the following criteria: Appropriate antibiogramm, adequate elusion characteristics, bactericidal (exception clindamycin), powder form (never use liquid AB), maximum addition of 10%/PMMA powder. Current principles of modern cementing techniques should be applied.
Post-operative systemic antibiotic administration is usually followed for only 10–14 days (exception: streptococci). We recommend an early and aggressive mobilization within the first 8 days post-operatively due to the cemented fixation an immediate mobilization under full weight bearing becomes possible in most cases.
Persistence or recurrence of infection remains the most relevant complication in the one-staged technique. As failures rates with a two-staged exchange have been described between 9% and 20% in non-resistant bacteria, the ENDO-Klinik data shows comparative results after 8–10 years of follow up, which were confirmed independently also by some other international reports and study groups.
In summary a cemented one-stage exchange offers various advantages. Mainly the need for only one operation, shorter hospitalization, reduced systemic antibiotics, lower overall cost and relatively high patient satisfaction. However a well-defined pre-operative planning regime including an experienced microbiologist is absolutely mandatory.
