Diagnostic Arthroscopy for Detection of Periprosthetic Infection in Painful Shoulder Arthroplasty

A Literature Review of Cutibacterium Acnes: From Skin Commensal to Pathogen in Shoulder Surgery

Cutibacterium acnes, previously known as Propionibacterium acnes, is a gram-positive rod in the pilosebaceous glands and commonly implicated in acne vulgaris. Its role in prosthetic joint infections, particularly in shoulder surgeries, has recently gained attention due to its prevalence around the shoulder girdle. This review collates evidence on the pathogenic role of C. acnes in shoulder surgeries, discussing preventive measures, risk factors, clinical presentation, investigation, and treatment strategies. C. acnes infections are complex, often presenting with non-specific symptoms and delayed diagnoses. Risk factors include male sex, presence of hair, shoulder steroid injections, and previous shoulder surgeries. Investigations such as inflammatory markers, synovial fluid analysis, diagnostic arthroscopy, tissue cultures, and advanced molecular techniques like next-generation sequencing and multiplex polymerase chain reaction are explored for their effectiveness in detecting C. acnes. Treatment strategies range from prolonged antibiotics and antibiotic spacers to single-stage and two-stage revision surgeries. Studies indicate that single-stage revision may provide better outcomes compared to two-stage revision. Effective management of C. acnes infections requires careful assessment, relevant investigations, and tailored treatment approaches. This review emphasizes the need for further research to address intraoperative contamination and to develop more efficient diagnostic and treatment methods.

Differences in Diagnostic Sensitivity of Cultures Between Sample Types in Periprosthetic Joint Infections: A Systematic Review and Meta-Analysis

BACKGROUND

Differences between the bacterial culture results of the preoperative fluid, intraoperative tissue, and sonication fluid of implants in the diagnosis of periprosthetic joint infection (PJI) are important issues in clinical practice. This study aimed to identify the differences in pooled diagnostic accuracy between culture sample types for diagnosing PJI by performing a systematic review and meta-analysis.

METHODS

This study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement. A comprehensive literature search of PubMed, Cumulative Index to Nursing and Allied Health Literature, and Cochrane Library databases was performed. Data extraction and study assessment using the quality assessment of diagnostic accuracy studies were performed independently by two reviewers. The pooled sensitivity, specificity, summary receiver operating characteristic curve, and area under the summary receiver operating characteristic curve were estimated for each sample type.

RESULTS

There were thirty-two studies that were included in the analysis after screening and eligibility assessment. The pooled sensitivities of preoperative fluid, intraoperative tissue, and sonication fluid for the diagnosis of PJI were 0.63 (95% confidence interval [CI] 0.56 to 0.70), 0.71 (95% CI 0.63 to 0.79), and 0.78 (95% CI 0.68 to 0.85), while the specificities were 0.96 (95% CI 0.93 to 0.98), 0.92 (95% CI 0.86 to 0.96), and 0.91 (95% CI 0.83 to 0.95), respectively. The area under the curves for preoperative fluid, intraoperative tissue, and sonication fluid were 0.86, 0.88, and 0.90, respectively.

CONCLUSIONS

Sonication fluid culture demonstrated better sensitivity compared with the conventional culture method, and preoperative fluid culture provided lower sensitivity in diagnosing PJI.

Hydrogen Peroxide May Reduce the Risk for Revision Surgery and Infection in Primary Shoulder Arthroplasty: Two-year Follow-up From a Prospective, Blinded, Controlled Trial

BACKGROUND

The purpose of this study was to determine whether the addition of hydrogen peroxide to the preoperative skin preparation for primary total shoulder arthroplasty is associated with a difference in patient-reported outcomes, risk for postoperative infection, and risk for revision surgery at a minimum of 2-year follow-up.

METHODS

This was a prospective, blinded, and controlled trial, which included a consecutive series of patients undergoing primary shoulder arthroplasty. The control group underwent standard sterile skin preparation using ethyl alcohol and ChloraPrep applicators, and the peroxide group had the same preparation with the addition of hydrogen peroxide between the alcohol and ChloraPrep applications. We then compared patient-reported outcome scores (American Shoulder and Elbow Surgeons Shoulder Score [ASES], simple shoulder test [SST], visual analog scale [VAS]), infections, and revision surgeries between the two groups at 2-year follow-up.

RESULTS

Of the 61 patients included in the original study, 52 of 58 (85%) living patients agreed to participate in this study. No preoperative differences were observed between groups. No difference was observed in ASES, SST, or VAS scores at 2 years. More revision surgeries were done in the control group (7 versus 2, P = 0.268) and Cutibacterium acnes infections (2 versus 0, P = 0.168).

CONCLUSION

The addition of hydrogen peroxide to the preoperative skin preparation before primary shoulder arthroplasty is safe, and additional research is warranted to investigate whether it may decrease the risk for revision surgery and postoperative C acnes infection.

LEVEL OF EVIDENCE

III.

Diagnostic Evaluation of Prosthetic Joint Infections of the Shoulder: What Does the Literature Say?

The total number of patients with a total shoulder arthroplasty (TSA) is increasing, and the number of patients experiencing a (TSA) prosthetic joint infection (PJI) also will increase. It is important that physicians know how to identify signs of infection, know the common pathogens, and know how to work up a shoulder PJI. This publication reviewed the current literature about presenting signs and symptoms, common shoulder pathogens and how they differ from total knee and hip pathogens, and what images, tests, and procedures can aid in identification of infection.

Diagnostic arthroscopy for periprosthetic shoulder arthroplasty infections: a systematic review and meta-analysis

Background

Periprosthetic joint infection of the shoulder (PJI) is a devastating complication with a reported incidence of 1%-15.4% and is often difficult to diagnose with current diagnostic tools including serologic tests and arthrocentesis. This systematic review evaluates the reliability and validity of arthroscopic biopsy in the current literature for the diagnosis of shoulder PJI.

Methods

MEDLINE, Scopus, Web of Sciences, Google Scholar, and Cochrane databases were queried electronically from inception to June 2022 for publications reporting diagnostic accuracy of shoulder arthroscopic biopsy for detecting infection after anatomic total shoulder arthroplasty, shoulder hemiarthroplasty, or reverse total shoulder arthroplasty. This systematic review was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

Results

After exclusion, our meta-analysis consisted of 7 articles with a total of 112 patients. The estimated pooled sensitivity and specificity of arthroscopic biopsy for confirmation of shoulder periprosthetic infection were 0.87 (95% confidence interval [CI]: 0.73-0.95) and 0.79 (95% CI: 0.67-0.88), respectively. The pooled positive likelihood ratio and negative likelihood ratio were 4.15 (95% CI: 2.57, 6.70) and 0.17 (95% CI: 0.08, 0.36), respectively. The aggregate positive predictive value was 73.58% (95% CI: 63.29%-81.82%), and aggregate negative predictive value was 89.83% (95% CI: 80.59%-94.95%). The diagnostic odds ratio of arthroscopic biopsy was 19.92 (95% CI: 4.96-79.99).

Conclusion

Arthroscopic biopsy in patients suspected of shoulder PJI has good diagnostic accuracy, with high sensitivity and specificity. Given the various biopsy protocols (such as devices, numbers, locations, etc.), further prospective studies are necessary to define the future role of arthroscopic biopsy in diagnosis and treatment.

Arthroscopic Management of Stiffness and Anterior Shoulder Pain Following Reverse Shoulder Arthroplasty

Arthroscopy following shoulder arthroplasty has primarily been described as a diagnostic tool in the setting of unexplained pain. However, this tool also can be used to potentially manage postoperative stiffness and pain following reverse shoulder arthroplasty. This Technical Note provides a stepwise approach to assessing and addressing limitations in range of motion as well as causes of postoperative impingement following reverse shoulder arthroplasty.

Better diagnostic value of tissue cultures obtained during mini-open and arthroscopic procedures compared with sterile punctures to identify periprosthetic shoulder infections: a retrospective cohort study

BACKGROUND

This study aimed to determine the sensitivity and specificity of sterile shoulder needle aspiration and cultures obtained during arthroscopic and mini-open procedures for detecting periprosthetic shoulder infections using tissue cultures from revision surgery as the gold standard.

METHODS

All shoulder arthroplasty patients who underwent a synovial fluid puncture between August 2012 and February 2018 were selected. In addition, arthroplasty patients with cultures obtained during arthroscopic or mini-open procedures between May 2014 and May 2021 were selected. When sterile punctures or biopsy procedures were followed by revision surgery with collection of 6 tissue cultures, patients were included in the study and efficacy measures were calculated.

RESULTS

Fifty-six patients were included in this study (with 57 punctures) and underwent analysis of puncture results after exclusions. Positive puncture results were found for Cutibacterium acnes, Staphylococcus aureus, Staphylococcus hominis, Actinomyces neuii, and Proteus mirabilis. These puncture cultures showed a sensitivity of 20.0% and specificity of 90.6%. From May 2014 to May 2021, 51 biopsy procedures were performed (15 arthroscopic and 36 mini-open); 37 biopsy procedures were included in this study (12 arthroscopic and 25 mini-open) for analysis after exclusions. Positive culture results were found for C acnes, Staphylococcus epidermidis, Staphylococcus saccharolyticus, and Streptococcus species. Arthroscopic biopsy cultures showed a sensitivity of 60.0% and specificity of 85.7%. For the mini-open biopsy cultures, the sensitivity and specificity were 66.7% and 85.7%, respectively.

CONCLUSIONS

Sterile punctures for culture have a low sensitivity and a high specificity for diagnosing periprosthetic shoulder infections. Tissue cultures obtained during mini-open and arthroscopic procedures have a higher sensitivity for detecting periprosthetic shoulder infections.

Management of periprosthetic infection after reverse shoulder arthroplasty

BACKGROUND

Periprosthetic shoulder infection (PSI) remains a devastating complication after reverse shoulder arthroplasty (RSA). Currently, scientific data related to the management of PSI are limited, and the optimal strategy and related clinical outcomes remain unclear. Guidelines from the Infectious Diseases Society of America for the management of periprosthetic joint infection are mainly based on data from patients after hip and knee arthroplasty. The aim of this study was to evaluate whether these guidelines are also valid for patients with PSI after RSA. In addition, the functional outcome according to the surgical intervention was assessed.

METHODS

An RSA database was retrospectively reviewed to identify infections after primary and revision RSAs, diagnosed between 2004 and 2018. Data collected included age, sex, indication for RSA, causative pathogen, surgical and antimicrobial treatment, functional outcome, and recurrence.

RESULTS

Thirty-six patients with a PSI were identified. Surgical treatment was subdivided into débridement and implant retention (DAIR) (n = 6, 17%); 1-stage revision (n = 1, 3%); 2-stage revision (n = 16, 44%); multiple-stage revision (>2 stages) (n = 7, 19%); definitive spacer implantation (n = 2, 6%); and resection arthroplasty (n = 4, 11%). The most common causative pathogens were Staphylococcus epidermidis (n = 11, 31%) and Cutibacterium acnes (n = 9, 25%). Recurrence was diagnosed in 4 patients (11%), all of whom were initially treated with a DAIR approach. The median follow-up period was 36 months (range, 24-132 months).

CONCLUSION

PSI is typically caused by low-virulence pathogens, which often are diagnosed with a delay, resulting in chronic infection at the time of surgery. Our results indicate that treatment of patients with chronic PSI with DAIR has a high recurrence rate. In addition, implant exchange (ie, 1- and 2-stage exchange) does not compromise the functional result as compared with implant retention. Thus, patients with chronic PSI should be treated with implant exchange. Future research should further clarify which surgical strategy (ie, 1-stage vs. 2-stage exchange) has a better outcome overall.

Diagnosis of orthopaedic-implant-associated infections caused by slow-growing Gram-positive anaerobic bacteria - a clinical perspective

Slow-growing Gram-positive anaerobic bacteria (SGAB) such as Cutibacterium acnes are increasingly recognized as causative agents of implant-associated infections (IAIs) in orthopaedic surgeries. SGAB IAIs are difficult to diagnose because of their non-specific clinical and laboratory findings as well as the fastidious growth conditions required by these bacteria. A high degree of clinical suspicion and awareness of the various available diagnostic methods is therefore important. This review gives an overview of the current knowledge regarding SGAB IAI, providing details about clinical features and available diagnostic methodologies. In recent years, new methods for the diagnosis of IAI were developed, but there is limited knowledge about their usefulness in SGAB IAI. Further studies are required to determine the ideal diagnostic methodology to identify these infections so that they are not overlooked and mistakenly classified as aseptic failure.

Role of pre-revision tissue biopsy in evaluation of painful shoulder arthroplasty: a systematic review and meta-analysis

BACKGROUND

Pre-revision tissue biopsy (PTB) for culture has been used as a diagnostic tool in the evaluation for periprosthetic joint infection among patients with a painful shoulder arthroplasty. The purpose of this study was to (1) determine the sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) of PTB culture results compared with results of "gold-standard" tissue biopsy for culture taken at the time of subsequent revision surgery (TBR), and (2) report the current indications and protocols described for use of PTB. The hypothesis was that PTB culture results would correlate highly with results of TBR and that protocols for PTB would vary by institution.

METHODS

By use of Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines, a systematic review and meta-analysis of English-language literature were performed using the Embase, MEDLINE, CINAHL (Cumulative Index to Nursing and Allied Health Literature), and Cochrane databases from inception through March 2020. Methodological Index for Non-randomized Studies (MINORS) validated grading criteria were used to summarize the quality and bias of included studies. Studies were included if an arthroscopic or open tissue biopsy was performed in patients who had previously undergone anatomic total shoulder arthroplasty, shoulder hemiarthroplasty, or reverse total shoulder arthroplasty as a separate procedure prior to revision of components, if applicable. Meta-analysis to identify the sensitivity, specificity, NPV, and PPV of PTB was performed. Analysis was performed by first defining 1 positive PTB culture result as infection and then defining 2 positive culture results as infection.

RESULTS

A total of 1751 titles were screened, and 66 full-text articles were reviewed for inclusion. Four total studies encompassing 72 cases met the inclusion criteria. All studies were small (N = 13 to N = 23), retrospective series, with all but 12 biopsies performed arthroscopically. Sixty-five patients (90.2%) underwent subsequent revision surgery and TBR. Of these patients, 23 (35.4%) had ≥1 positive culture result with PTB and TBR. By this definition, the sensitivity of PTB was 92.0% (95% confidence interval [CI], 72.5%-98.6%); specificity, 70.0% (95% CI, 53.3%-82.9%); PPV, 65.7% (95% CI, 47.7%-80.3%); and NPV, 93.3% (95% CI, 76.5%-98.8%). For 2 positive PTB results, the sensitivity of PTB was 100% (95% CI, 51.7%-100%); specificity, 50.0% (95% CI, 31.4%-68.6%); PPV, 33.3% (95% CI, 14.4%-58.8%); and NPV, 100% (95% CI, 69.9%-100%). No complications of PTB were reported. The mean Methodological Index for Non-randomized Studies (MINORS) grade was 11.4 (range, 8.5-14).

CONCLUSION

PTB is a sensitive diagnostic modality with a high NPV that may aid in the diagnosis of shoulder periprosthetic joint infection in patients with a painful shoulder arthroplasty. Given the disparate biopsy protocols, greater standardization of clinical best practices and broader prospective studies are necessary to define the future role of PTB in dictating treatment.

Preoperative Skin Cultures Predict Periprosthetic Infections in Revised Shoulder Arthroplasties: A Preliminary Report

Current approaches do not provide a practical method for the accurate prediction of a Cutibacterium periprosthetic joint infection (PJI) in failed arthroplasties. Thus, surgeons revising failed arthroplasties must decide whether to exchange the implants and to institute antibiotic treatment without knowing the results of cultures of deep specimens obtained at the revision procedure. This study tests the hypothesis that the results of preoperative culture specimens of the skin surface obtained in the clinic can predict the presence of culture-positive Cutibacterium PJIs.

METHODS

Revision shoulder arthroplasties performed between October 3, 2017, and February 4, 2020, that had both preoperative clinic culture specimens and surgical culture specimens were included in this analysis. Culture results were assigned a value from 0 to 4. The percentage of the total skin bacterial load contributed by Cutibacterium (Cutibacterium percentage) was determined. To reduce concern about contamination, a robust criterion for culture-positive Cutibacterium PJI was applied: ≥2 surgical specimens with a Cutibacterium value of ≥1. The predictive values for a culture-positive Cutibacterium PJI were determined for a clinic skin culture Cutibacterium value of >1 and a clinic skin percentage of Cutibacterium of ≥75%.

RESULTS

Eighteen cases met the inclusion criteria; of these, 7 (6 male patients) met our criterion for a culture-positive Cutibacterium PJI. For all patients, a preoperative clinic skin Cutibacterium value of >1 predicted the presence of a culture-positive Cutibacterium PJI with an accuracy of 89%, and a clinic skin Cutibacterium percentage of ≥75% predicted the presence of a culture-positive Cutibacterium PJI with an accuracy of 94%. For male patients, a preoperative clinic skin Cutibacterium value of >1 predicted the presence of a culture-positive Cutibacterium PJI with an accuracy of 91%, and a clinic skin Cutibacterium percentage of ≥75% predicted the presence of a culture-positive Cutibacterium PJI with an accuracy of 100%.

CONCLUSIONS

A simple culture specimen of the unprepared skin surface obtained in a clinic prior to revision shoulder arthroplasty may provide valuable assistance to surgeons planning a revision arthroplasty.

LEVEL OF EVIDENCE

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Arthroscopic Evaluation and Treatment of Complications That Arise Following Prosthetic Shoulder Arthroplasty

Arthroscopy may be used to diagnose symptomatic glenoid loosening following anatomic total shoulder arthroplasty (aTSA), and arthroscopic glenoid component removal may suffice as treatment for some patients. Arthroscopy may be used to diagnose shoulder prosthetic joint infection (PJI) following aTSA and reverse shoulder arthroplasty (RSA). Tissues are biopsied from multiple sites within the joint and the subdeltoid or subacromial space, and they are cultured for a minimum of 14 days. Postoperative adhesions arising after prosthetic shoulder arthroplasty (PSA) may be released arthroscopically. However, other problems contributing to shoulder stiffness such as component malpositioning or shoulder PJI require additional intervention. Arthroscopy may be used to repair select rotator cuff tears that arise acutely following aTSA, but chronic attritional tears do not heal after repair; therefore, revision to RSA often is needed. Many complications following PSA, such as infection, fixed instability, humeral component loosening, and major humeral or glenoid bone loss, are not adequately treated using arthroscopic techniques. However, arthroscopy following PSA may help to diagnose and treat other complications, even as the precise indications following aTSA and RSA remain unclear.

Arthroscopic Circumferential Release for Stiff Reverse Total Shoulder Arthroplasty

Stiffness is a well-known complication after reverse shoulder arthroplasty. Although multiple factors may be involved, the main cause for stiffness is rarely identified. Imaging studies frequently are inconclusive in ruling out mechanical or biological causes. Periprosthetic infection should be always suspected, but the absence of major clinical signs and accurate diagnostic tests is frequent. A lack of objective criteria establishing a diagnosis and when to proceed with revision surgery is often present in such cases. Moreover, additional surgical procedures should be carefully evaluated, as they can represent a point of no return. Shoulder arthroscopy plays an increasingly important role in these cases, either as a diagnostic or therapeutic tool. There are no reports about arthroscopy on stiffness after reverse shoulder arthroplasty. In this Technical Note, we describe an arthroscopic technique aimed to identify potential causes of reverse shoulder arthroplasty stiffness. Subsequent circumferential release is described and discussed.

Hemiarthroplasty and Total Shoulder Arthroplasty Conversion to Reverse Total Shoulder Arthroplasty

PURPOSE OF REVIEW

The incidence of shoulder arthroplasty is increasing dramatically for primary arthroplasty but also for revision arthroplasty. Revision to reverse total shoulder arthroplasty is increasingly the salvage operation for failed primary arthroplasty. The purpose of this review is to explore the indications for and results of revision reverse total shoulder arthroplasty.

RECENT FINDINGS

Despite relatively high complication and reoperation rates with revision shoulder replacement, revision of failed hemiarthroplasty or total shoulder arthroplasty to reverse total shoulder arthroplasty improves outcomes for many patients. A failed hemiarthroplasty or total shoulder arthroplasty is frequently disabling for the patient and because the surgical revision options are often limited only to reverse total shoulder arthroplasty, the potential improvement is often worth the higher surgical complication or reoperation rate. Due to the challenges inherent in revision arthroplasty, revision of primary arthroplasty to reverse total shoulder arthroplasty, outcomes are poorer than primary reverse total shoulder arthroplasty. Despite these limitations, patient postoperative pain and function do increase from preoperative levels making conversion of hemiarthroplasty or anatomic total shoulder to reverse total shoulder arthroplasty an important option for a challenging problem.

Editorial Commentary: In Search of the Optimal Diagnostic Tool for Periprosthetic Joint Infections of the Shoulder

A number of perioperative diagnostic tests are currently available to evaluate for the presence of periprosthetic joint infection (PJI) in painful shoulder arthroplasties. However, data on the utility of these tests are more limited in the shoulder, with worse diagnostic performance compared with the evaluation of hip and knee PJI because of the low virulence of the commonly cultured shoulder organisms, such as Cutibacterium acnes. Diagnostic arthroscopy with culturing of arthroscopic tissue samples may allow for a more definitive diagnosis and treatment planning in patients with shoulder PJI prior to revision shoulder arthroplasty, but data on the efficacy of this procedure have been limited.