Results of cement spacer sonication in the second stage of two-stage treatment of shoulder arthroplasty infection

One- vs. Two-Stage Revision for Periprosthetic Shoulder Infections: A Systematic Review and Meta-Analysis

Periprosthetic shoulder infection (PSI) remains a challenging complication after shoulder arthroplasty. Therapeutic options include one- or two-stage revision, irrigation and debridement, and resection arthroplasty. With our systematic review and meta-analysis, we aimed to compare one- and two-stage revisions for periprosthetic shoulder joint infections and determine the most appropriate therapeutic procedure. We performed an extensive literature search in PubMed, Ovid Medline, Cochrane Library, Web of Science, and CINAHL and filtered out all relevant studies. The meta-analysis was performed using the random-effects model, heterogeneity was analyzed using I2, and publication bias was assessed using the Egger's test. A total of 8 studies with one-stage revisions, 36 studies with two-stage revisions, and 12 studies with both one-stage and two-stage revisions were included. According to the random-effects model, the reinfection rate for the entirety of the studies was 12.3% (95% Cl: 9.6-15.3), with a low-to-moderate heterogeneity of I2 = 47.72%. The reinfection rate of the one-stage revisions was 10.9%, which was significantly lower than the reinfection rate of the two-stage revisions, which was 12.93% (p = 0.0062). The one-stage revision rate was significantly lower with 1.16 vs. 2.25 revisions in the two-stage revision group (p < 0.0001). The postoperative functional outcome in one-stage-revised patients was comparable but not statistically significant (p = 0.1523). In one- and two-stage revisions, most infections were caused by Cutibacterium acnes. In summary, our systematic review and meta-analysis show the superiority of single-stage revision regarding reinfection and revision rates in periprosthetic shoulder joint infection.

Periprosthetic shoulder infection management: one-stage should be the way: a systematic review and meta-analysis

BACKGROUND

There is still no consensus among surgeons on whether to perform a 1- or 2-stage surgical revision in infected shoulder arthroplasties. The aim of this systematic review and meta-analysis is to rigorously synthesize published studies evaluating the clinical outcomes, recurrence of infection, and other clinical complications in order to discuss which is the best strategy for treating periprosthetic joint infection after shoulder arthroplasty.

METHODS

Upon research using the PubMed, Scopus, and Web of Science databases, in November 2022, studies that presented 1- or 2-stage surgical revision as a treatment for periprosthetic joint infection after shoulder arthroplasty and assessed the reinfection rate on these patients, as well as other clinical outcomes, with a minimum follow-up of 12 months, were included. Study quality was evaluated using the Methodological Index for Non-Randomized Studies (MINORS) score. Reinfection and complication rates were extracted, and pooled estimates were calculated using the random-effect model.

RESULTS

After careful screening, 44 studies were included, 5 reporting on 1-stage and 30 on 2-stage revisions and 9 assessing both strategies. A total of 185 shoulders were reported in 1-stage revision studies, whereas 526 shoulders were reported in 2-stage revision studies. The overall pooled random-effects reinfection rate was 6.68% (95% confidence interval [CI]: 3.76-10.13), with low heterogeneity (I2 = 28%, P = .03). One-stage revision showed a reinfection rate of 1.14% (95% CI: 0.00-4.88), whereas 2-stage revision analysis revealed a reinfection rate of 8.81% (95% CI: 4.96-13.33). There were significant statistical differences between 1- and 2-stage reinfection rates (P = .04). The overall pooled rate for other clinical complications was 16.76% (95% CI: 9.49-25.15), with high heterogeneity (I2 = 70%, P < .01). One-stage revision had a complication rate of 6.11% (95% CI: 1.58-12.39), whereas the 2-stage revision complication rate was 21.26% (95% CI: 11.51-32.54). This difference was statistically significant (P = .03).

CONCLUSIONS

This is the first systematic review and meta-analysis showing significant statistical differences between 1- and 2-stage surgical revision in infected shoulder arthroplasties. Provided the right conditions exist, 1-stage revision shows better results in infection control, with lower clinical complications and possible better clinical outcomes.

Comparison of surgical treatment options in periprosthetic shoulder infections: a systematic review from 2016 to 2022

Background

Periprosthetic shoulder infection (PSI) management proves to be challenging because of patient morbidity, poor outcomes and need for reoperations. Different surgical treatment methods have been defined; however, a prominent method could not be determined. This systematic review investigated the most recent articles about various treatment modalities used in the surgical treatment of PSI to find the most effective method in terms of infection clearance and function.

Methods

The keywords were searched using PubMed (MEDLINE), ScienceDirect (Elsevier), and Google Scholar databases on September 30, 2022. Studies which report on operative treatment and have longer than 2-year follow-up were included in this review. Of the 555 studies in total, 16 were reviewed. The absence of symptomatic persistent infection (PI) during follow-up was regarded as a satisfactory outcome. Functional outcomes were analyzed according to the reported mean pooled Constant and Murley Score (CMS) and shoulder forward elevation degree (FE) for each treatment group.

Results

A total of 339 patients (139 female, 197 male) with 342 shoulders from sixteen studies were included. The mean age of the patients was 67.5±3.8 years, mean follow-up duration was 53.3±19.5 months. In total, 217 shoulders were treated with two-stage revision, 59 were treated with one-stage revision, 37 were treated with definitive spacer, 23 were treated with debridement, antibiotics, and implant retention (DAIR), and 6 were treated with resection arthroplasty. The PI rate in whole treatment groups was 9.9%. The PI rate was significantly highest in the DAIR group (30.4%, P=0.001), while there was no significant difference between other treatment groups (P=0.23). CMS and FE were available for 156 and 190 shoulders, respectively. CMS was highest in the one-stage revision group (63.4±5.9, P=0.001), and FE was highest in the DAIR group (119.3°±28.5°, P=0.001).

Conclusions

The revision surgeries (one-stage and two-stage revision) were more effective than the non-revision surgeries in functional outcomes. In terms of infection clearance, revision procedures were more successful. Surgeons should prefer revision methods over non-revision procedures when feasible.

Two-stage shoulder arthroplasty after deep infection of the shoulder caused by arthroplasty, osteosynthesis or other surgical procedures: microbial spectrum, complications and functional outcome after at least 1 year follow-up

PURPOSE

Infection represents probably the most challenging complication in shoulder arthroplasty and all other surgical procedures of the shoulder. A deep infection of the shoulder is often combined with a destruction of the joint and a loss of function. In many cases the arthroplasty is the last resort for these patients to obtain a satisfactory function. The objective of this study was to determine outcome data on microbiota and clinical results of a two-stage shoulder arthroplasty procedure after deep infection of the shoulder.

METHODS

Twenty-six patients with a deep shoulder infection after arthroplasty, osteosynthesis, or rotator-cuff repair were included, while two patients had an empyema without prior surgery. All underwent initial surgical debridement with implantation of an antibiotic-loaded spacer, followed by postoperative systemic antibiotics. The patients obtained definitive shoulder arthroplasty in a second surgery. None of the patients had to undergo more than two surgeries before the arthroplasty. The follow-up analysis including microbiota results, complication rates, and functional outcomes could be determined after at least 1 year in 60% of patients (n = 16).

RESULTS

The most frequently detected microorganisms were S. epidermidis (31%, n = 10) and Cutibacterium acnes (19%, n = 6). In 28% (n = 9) of cases multi-drug resistant bacteria were detected and in 35% (n = 8) of cases more than one microorganism was found. The overall revision rate was 42%, 11 of 26 patients, in the first 8 weeks after arthroplasty. Reasons for revision were joint dislocations in 23% (n = 6), 15% (n = 4) postoperative hematomas, one (4%) re-infection and one (4%) periprosthetic fracture. At follow-up after 19.3 ± 5.5 months postoperatively, a mean abduction of 113.4°, anteversion of 122.8° and external rotation of 14° was found, with an average age and gender-adjusted Constant Score of the affected shoulder of 63. The subjects' pain and impairment in normal life measured by a questionnaire with school grades were significantly reduced (p < 0.05) as compared to prior shoulder arthroplasty.

CONCLUSION

The most relevant bacteria in the study cohort were Staphylococcus subspecies and to a lower extent Cutibacterium acnes. A high number of multi-drug resistant and mixed microbiota spectra were detected, defining a need to adapt therapeutic regimen targeting these microbiotas. The two-stage shoulder arthroplasty after a deep infection resulted in excellent infection control with however high early postoperative rates for joint dislocation (23%) and hematomas (15%). At follow-up a stable joint was achieved with a sufficient functional outcome and satisfying outcome for activities of daily living and pain.

CLINICAL TRIAL

Trial registration number: DRKS00016927, date of registration: 2019/03/19.

Changes in microbiological spectrum and antibiotic susceptibility in two-stage exchange for periprosthetic shoulder infections

BACKGROUND

Periprosthetic joint infections (PJI) are a major concern in shoulder arthroplasty, which in some cases require two-stage exchange. While it was shown that low-virulence bacteria are the most isolated pathogens in shoulder PJI, little is known about changes in microbiological spectrum and resistance patterns during two-stage revision.

METHODS

This retrospective study included all patients (n = 25) who received a two-stage revision from January 2011 to December 2020 for shoulder PJI in one institution. Microbiological spectrum, antimicrobial resistance patterns, and re-revision rates of culture positive first- and second-stage procedures were analyzed. The mean follow-up time was 29.7 months (range 8; 115 months). At final follow-up, subjective shoulder value (SSV) and visual analog scale (VAS) score for pain and satisfaction with the surgery were assessed.

RESULTS

In 25 patients, a total of 54 2-stage exchange procedures were performed and positive cultures were obtained in 36 of these surgeries (66.7%). A total of 7 out of 25 patients (28.0%) showed a positive microbiological culture at first and second stages. In those patients, the mean time between first and second stages was 30.9 weeks (range 6; 70). Three out of those seven patients (42.9%) had a polymicrobial spectrum with one microorganism persistent at stage two, including Cutibacterium acnes (n = 1) and Staphylococcus epidermidis (MRSE) (n = 2). In all these cases, antimicrobial resistance patterns changed. All cultures with monomicrobial spectrum (n = 4) at first stage showed a changed spectrum. Patients with positive first- and second-stage revisions showed a mean SSV of 49.3% ± 23.5 versus 52.9% ± 29.5 in single positive patients (p = 0.76). Re-revision was performed in five cases, two of those in patients with positive first- and second-stage cultures.

CONCLUSION

There is a high rate of changes in microbiological spectrum and resistance patterns between culture positive first- and second-stage procedures as well as subsequent re-revisions. Intraoperative samples during reimplantation should be taken and resistance reconsidered in case of re-revision.

One Versus 2-Stage Revision for Shoulder Arthroplasty Infections: A Systematic Review and Analysis of Treatment Selection Bias

BACKGROUND

There is controversy regarding the optimal treatment for infection following shoulder arthroplasty. The purpose of this systematic review is to analyze the bias in treatment selection, infection clearance rates, and functional outcomes after 1 versus 2-stage revision surgery for periprosthetic shoulder infections.

METHODS

A systematic search strategy following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines was conducted in 4 phases. Articles were identified using MEDLINE (PubMed), Embase (Elsevier), and Cochrane Library databases with Boolean search terms related to infection after shoulder arthroplasty. Included articles were analyzed for quality, and data were extracted for use. Preoperative treatment selection bias was analyzed and postoperative infection clearance rates and functional outcome scores were compared between 1 and 2-stage revision surgery for periprosthetic shoulder infection.

RESULTS

Overall, 163 1-stage shoulder procedures and 289 2-stage shoulder procedures were included in the analysis. Cutibacterium acnes was the organism most frequently grown on culture (37%) followed by coagulase-negative Staphylococcus (19%). The overall infection clearance rate was 95.6% for 1-stage and 85.2% for 2-stage procedures. In a comparison of the change in outcome scores from preoperatively to postoperatively between 1-stage and 2-stage revision, the Constant-Murley Score (CMS) improved 21.0 points (1-stage) versus 22.8 points (2-stage), the American Shoulder and Elbow Surgeons (ASES) score improved 26.2 points versus 33.6 points, and the Simple Shoulder Test (SST) score improved 3.5 points versus 6.4 points, respectively. Overall, 23 of 26 studies cited a reason for selection of a 1 versus 2-stage procedure, which was due to standard treatment protocol in 10 studies, based on the timing of the infection (acute versus subacute versus chronic) in 5, due to a combination of factors (age, comorbidities, intraoperative appearance, adequacy of debridement, bone loss) in 6, and due to preoperative identification of a specific organism in 2.

CONCLUSIONS

One-stage revisions resulted in higher infection clearance rates; however, 2-stage revisions resulted in greater functional improvement as measured with ASES and SST scores from the preoperative assessment to the final postoperative follow-up. The decision between 1 and 2-stage revisions is due to a combination of factors including pathogen type, timing of infection, findings on the preoperative clinical examination, the patient's own decision, the surgeon's preference, and the intraoperative soft-tissue/osseous appearance, which may have biased the overall results. There is no consensus in the literature on the decision between 1 and 2-stage treatment for periprosthetic shoulder infection, which is based on a combination of factors. However, both treatment strategies are effective in treating periprosthetic shoulder infection.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Sonication fluid culture of antibiotic-loaded bone cement spacer has high accuracy to confirm eradication of infection before reimplantation of new prostheses

BACKGROUND

Sonication fluid culture of antibiotic-loaded bone cement spacer has been used to predict reinfection of two-stage revision, but its value remains disputable. This study aims to evaluate the association between the culture result of the sonicated spacer and the status of patients with periprosthetic joint infection receiving two-stage revision.

MATERIALS AND METHODS

A comprehensive electronic literature search was performed through four databases including PubMed, Embase/Ovid, and EBSCO, and the Cochrane Library to retrieve studies in which sonication fluid culture of the antibiotic spacer was conducted before reimplantation. The pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) were calculated to assess the association between the culture result of sonicated spacer and prognosis of the two-stage revision.

RESULTS

Eleven eligible studies comprising 603 artificial joints with PJI (134 suffering a clinical failure of two-stage revision) were included in the quantitative analysis. The pooled incidences of positive culture of sonicated spacer and intraoperative tissue were 0.14 (95% confidence interval [CI] 0.08-0.21) and 0.14 (95% CI 0.08-0.20), respectively. A positive culture of sonicated antibiotic-loaded bone cement spacer illustrated moderate sensitivity (0.31, 95% CI 0.13-0.58) but high specificity (0.94, 95% CI 0.86-0.98) for the diagnosis of therapeutic failure of two-stage revision; the pooled DOR was 7.67 (95% CI, 3.63-16.22). Meanwhile, the pooled sensitivity, specificity, and DOR of intraoperative tissue culture during the two-stage revision to predict therapeutic failure were 0.32 (95% CI, 0.20-0.47), 0.96 (95% CI, 0.92-0.98), and 10.62 (95% CI, 4.90-23.01), respectively.

CONCLUSIONS

Sonication fluid culture of antibiotic-loaded bone cement spacer revealed high accuracy for confirming eradication of infection before reimplantation of new prostheses and therefore could be used as a supplement for assessing therapeutic effect for PJI. However, both sonication fluid culture and intraoperative tissue culture from antibiotic-loaded bone cement spacer showed restricted yield for the prediction of a septic failure after the two-stage revision of PJI. Large-scale, prospective studies are still needed to testify current findings.

Periprosthetic Infection After Reverse Shoulder Arthroplasty: a Review

PURPOSE OF REVIEW

Periprosthetic infection is a relatively rare but potentially devastating complication after shoulder arthroplasty. The purpose of this article is to review the incidence, diagnosis, prevention, and management of periprosthetic infections after reverse shoulder arthroplasty, with a focus on literature published within the last 5 years.

RECENT FINDINGS

The 2018 International Consensus Meeting on Musculoskeletal Infection provides us with a framework for the diagnosis and management of periprosthetic infections after shoulder arthroplasty. Reverse shoulder arthroplasty has a higher reported rate of infection compared with anatomic total shoulder arthroplasty. Our current diagnostic tests do not appear to be as sensitive when compared with the hip and knee literature. Similar success has been reported with single and two-stage revision protocols, although prospective comparative data are lacking. The significance of unexpected positive cultures during revision arthroplasty remains unclear. We report current diagnostic and therapeutic options for periprosthetic infection after reverse shoulder arthroplasty. Much of the current literature does not distinguish between anatomic and reverse shoulder arthroplasty. Further high-level studies are warranted to refine these definitions and guide management.

Failure After 2-Stage Exchange Arthroplasty for Treatment of Periprosthetic Joint Infection: The Role of Antibiotics in the Cement Spacer

BACKGROUND

Failure after a 2-stage exchange surgery for periprosthetic joint infection (PJI) is high. Previous studies demonstrated that positive cultures at reimplantation are associated with failure afterward. The aim of this multicenter study was to define the role of antibiotics in the cement spacer in relation to reimplantation cultures and subsequent failure.

METHODS

We retrospectively evaluated 2-stage exchange procedures between 2000 and 2015. Culture-negative PJIs, cases in which no cultures were obtained during reimplantation, and cases without data on cement spacers were excluded.

RESULTS

Three hundred forty-four cases were included. The rate of positive cultures during reimplantation was 9.5% for cement spacers containing a glycopeptide (27/284) (with or without an aminoglycoside) vs 21.7% for those containing monotherapy with an aminoglycoside (13/60) (P = .008), and was mostly attributed by a reduction in coagulase-negative staphylococci (CoNS) (17% vs 2%, P < .001). The failure rate was >2-fold higher at 40.0% (16/40) in cases with positive cultures at reimplantation compared to 15.8% (48/304) for those with negative cultures (P < .001). Overall, a glycopeptide in the cement spacer was not associated with a lower failure rate (18% vs 23%, P = .3), but was associated with lower failure due to CoNS (2.5% vs 13.3%, P < .001).

CONCLUSIONS

In a 2-stage exchange procedure for PJI, adding a glycopeptide to the cement spacer reduces the rate of positive cultures during reimplantation and is associated with a lower failure rate due to CoNS afterward.

Sonication in shoulder surgery: is it necessary?

PURPOSE

The objective of the present study was to determine whether sonication yields greater sensitivity when compared with the traditional tissue culture in detecting peri-implant infections in shoulder surgery.

METHODS

It is a retrospective study that includes 99 shoulder surgeries with implants explanted. The inclusion criteria required at least four tissue cultures, sonication of the material explanted, and a minimum follow-up of two years. Patients were classified according to the definition of periprosthetic shoulder infection of the 2018 International Consensus Meeting on Orthopedic Infections. The classifications are definitive infection, probable infection, possible infection, and unlikely infection.

RESULTS

Among the 99 surgical procedures, 31 were considered definitive infections, 11 possible/probable infections, and 57 unlikely infections. Considering the cases with a definitive infection, the sensitivity of the tissue culture was 87.09% and the sensitivity of sonication stood at 80.64% (p = 0.406). Analyzing the cases with a definitive infection and those having a possible/probable infection together and comparing them with those with unlikely infection, the sensitivity of sonication was 80.4% and the sensitivity of the tissue culture came to 91.4%. The specificity of the sonication was 98.1% and the specificity of the tissue culture was 99.6%.

CONCLUSION

The sensitivity of sonication in shoulder surgery (80.64%) is not superior to the sensitivity of the tissue culture (87.09%). Specificity remains high with both methods, being 98.1% in the sonication group and 99.6% in the tissue culture. Sonication brings no benefit to the detection of shoulder per-implant infections.

[Two-stage reverse total shoulder arthroplasty for treating postoperative deep infection after internal fixation of proximal humeral fracture]

OBJECTIVE

To summarize the effectiveness of two-stage reverse total shoulder arthroplasty for treating postoperative deep infection after internal fixation of the proximal humeral fracture.

METHODS

Between June 2014 and January 2018, 17 patients with deep infection and humeral head necrosis or bone nonunion after internal fixation of proximal humeral fractures were treated. There were 8 males and 9 females, aged from 52 to 78 years (mean, 63.8 years). The infection occurred at 19-66 months after the initial internal fixation (mean, 34.8 months). Microbial culture of joint fluid was positive in 14 cases and negative in 3 cases. The preoperative Constant score, American shoulder and elbow surgeons (ASES) score, and visual analogue scale (VAS) score were 36.41±8.65, 31.06±7.43, and 7.29±0.99, respectively. The preoperative ranges of forward flexion, abduction, external rotation were (45.88±12.46), (42.18±12.31), and (16.76±4.92)°, respectively. The preoperative range of internal rotation was buttock in 9 cases, lumbosacral joint in 3 cases, L 3 in 5 cases. At the first-stage surgery, the thorough debridement was done and the antibiotic-impregnated bone cement spacer was placed after the removal of internal fixation. After the infections disappeared, the two-stage reverse total shoulder arthroplasty was performed. The mean interval between the two procedures was 4.2 months (range, 3.0-6.5 months).

RESULTS

All the incisions healed primarily and no complications such as recurrent infection or vascular nerve injury occurred. All patients were followed up 15-32 months (mean, 22.0 months). At last follow-up, the ranges of forward flexion, abduction, and external rotation were (109.00±23.66), (98.53±16.92), (41.41±6.82)°, respectively; and the range of internal rotation was lumbosacral joint in 5 cases, L 3 in 8 cases, T 12 in 4 cases. The range of motion of shoulder joints at last follow-up was significant improved when compared with the preoperative range of motion ( P<0.05). The Constant score (64.88±8.70), ASES score (65.18±8.10), and VAS score (2.94±1.25) were significantly superior to the preoperative scores ( P<0.05). X-ray films showed that no prosthesis loosening occurred.

CONCLUSION

Two-stage reverse total shoulder arthroplasty is an effective treatment for the postoperative deep infection after internal fixation of the proximal humeral fracture, which has advantages of low risk of infection recurrence, good shoulder function, and satisfactory short-term effectiveness.

One- or two-stage exchange for periprosthetic shoulder infection: Systematic review and meta-analysis

INTRODUCTION

One-stage exchange is the gold-standard for management of periprosthetic shoulder infection. The present review compares efficacy between 1- and 2-stage exchange in this indication.

MATERIAL AND METHODS

We performed a systematic literature review and meta-analysis following the "Preferred Reporting Items for Systematic Reviews and Meta-Analyses" (PRISMA) criteria. The literature search used the Medline, Embase and Central data-bases. The studies included assessed 1- and 2-stage exchange in periprosthetic shoulder infection. The main outcome was reinfection rate, and the secondary outcome postoperative complications rate.

RESULTS

Twenty-one studies, for 501 patients, were included: 5 assessing 1-stage exchange, 11 2-stage, and 5 both. Mean follow-up was 4.3 years (range, 2-6.1 years). Mean reinfection rates ranged between 0 and 50% in 1-stage exchange and between 0 and 36.8% in 2-stage exchange. The combined rate was 7% (95% CI, 3.8-12.5%) in 1-stage and 21.3% (95% CI, 16-27.9%) in 2-stage exchange. Mean complications rates ranged between 0 and 50% in 1-stage exchange and between 5.7% and 73%% in 2-stage exchange. The combined rate was 17% (95% CI, 11.9-23.9%) in 1-stage and 32.8% (95% CI, 25.8-40.6%) in 2-stage exchange.

DISCUSSION

To our knowledge, the present meta-analysis is the first to assess results in 1- and 2-stage exchange for chronic periprosthetic shoulder infection.

CONCLUSION

One-stage exchange seemed to provide better results, with less reinfection and fewer complications than 2-stage exchange.

LEVEL OF EVIDENCE

I, meta-analysis.

Proceedings from the 2018 International Consensus Meeting on Orthopedic Infections: management of periprosthetic shoulder infection

The Second International Consensus Meeting on Orthopedic Infections was held in Philadelphia, Pennsylvania, in July 2018. A multidisciplinary team of international experts from all 9 subspecialties of orthopedic surgery and allied fields of infectious disease, microbiology, and epidemiology was assembled to form the International Consensus Group. The following consensus proceedings from the International Consensus Meeting involve 30 questions pertaining to the management of periprosthetic shoulder infection.

Sonication Culture of Antimicrobial Agent-Containing Cement Spacers Removed during Staged Revisions for Arthroplasty Infection

Diagnosis of persistent infection at the time of reimplantation for staged revision of infected arthroplasties is challenging. Implant sonication culture for the diagnosis of prosthetic joint infection (PJI) has improved sensitivity compared to standard periprosthetic tissue culture. We report our experience with periprosthetic tissue culture and sonication culture of antimicrobial agent-containing cement spacers (ACSs) collected during second stages of staged revisions for arthroplasty infection. We studied 87 ACSs from 66 patients undergoing two-stage revision arthroplasty for PJI submitted for sonication culture, along with conventional periprosthetic tissue cultures. Two or more positive periprosthetic tissue cultures with the same organism were considered a positive tissue culture. For sonication culture, ≥20 CFU of bacteria per 10 ml of sonicate fluid was considered positive. The sensitivity and specificity of periprosthetic tissue and ACS sonication culture in detecting persistent infection, as well as their association with outcome, were assessed. Persistent infection occurred in 26% of cases. Periprosthetic tissue and sonicate fluid culture had specificities of 96.3 and 100% (P = 0.50), respectively, and sensitivities of 31.6 and 26.3% (P = 1.00), respectively, for the diagnosis of persistent infection. Thirteen subjects deemed not to have persistent infection at time of reimplantation and who had negative periprosthetic tissue and sonicate fluid cultures subsequently developed overt infection. Sonication culture of cement spacers identifies a similar proportion of patients with persistent infection during staged revisions, as detected by periprosthetic tissue cultures; both have low sensitivities to detect persistent infection.