Transcutaneous compression suture with iodine gauze for wound closure in revision surgery for therapy-resistant periprosthetic shoulder infections

Background

To successfully treat a periprosthetic infection, successful bacteria eradication and successful wound closure are mandatory. Despite adequate surgical débridement in the deep, persistence of wound drainage and subsequent persistence of periprosthetic infection may occur, especially in patients with compromised soft tissue conditions. This study presents a transcutaneous compression suture technique with iodine gauze that was used in patients with persistent wound secretion in therapy-resistant periprosthetic shoulder infections in order to achieve successful infection control and wound healing.

Methods

All patients with persistent periprosthetic or implant-associated shoulder joint infections despite correct previous surgical and antibiotic therapy attempts were included in the study. In all patients, in addition to repeat deep surgical débridement, a transcutaneous "iodine-gauze-compression-suture" was performed with postoperative antibiotic therapy. The primary endpoint was infection control; the secondary endpoint was wound healing rate; and the third endpoint was complication rate after index surgery.

Results

Ten consecutive patients with a mean age of 74 (±7.6) years and a mean follow-up of 14 (±2) months were included. All ten patients showed infection control and successful wound healing, with no need for further revision surgery. In 8 out of 10 patients, the wound healing was fast and completely uncomplicated. Two out of 10 patients showed delayed wound healing with fibrin coatings for 3 and 4 weeks, respectively. No additional intervention was necessary in both patients.

Conclusions

Transcutaneous iodine gauze compression sutures were used to achieve successful infection control without additional revision surgery in 10 out of 10 patients who previously underwent surgery with failed infection control. This wound closure technique is a reliable adjunctive therapy method in the treatment of implant-associated infections of the shoulder in patients with fragile wound conditions.

The role of serum D-Dimer for the diagnosis of periprosthetic shoulder infection

INTRODUCTION

D-Dimer was recently identified as an additional biomarker in the diagnosis of hip and knee periprosthetic joint infection (PJI). Currently, there is only one study in literature dealing with the role of D-Dimer in the diagnosis of shoulder PJI. The purpose of this study was, therefore, to validate the sensitivity and specificity of D-Dimer in detecting shoulder PJI.

MATERIALS AND METHODS

All patients, who underwent septic or aseptic revision shoulder arthroplasty in our institution between November 2018 und March 2021, were analyzed. Our cohort consisted of 30 patients, of that 14 (47%) had a shoulder PJI according the last proposed criteria of the International Consensus Meeting. The diagnostic validity of serum D-Dimer regarding the detection of PJI was analyzed.

RESULTS

The mean D-Dimer level was significantly higher for the patients with shoulder PJI compared to patients with aseptic failure (1.44 ± 1 mg/l vs. 0.76 ± 0.6 mg/l, p = 0.025). Coagulase-negative staphylococci were the most commonly isolated pathogens, in 9/14 patients (64%), followed by Cutibacterium acnes in 5/14 patients (36%). According to the ROC analysis, a serum D-Dimer threshold of 0.75 mg/l had a sensitivity of 86% and a specificity of 56% for detection of a shoulder PJI. The area under curve was 0.74. A serum C-reactive protein (CRP) cutoff of 10 mg/l showed a sensitivity of 69% and a specificity of 88%. When both serum D-Dimer and CRP above the thresholds of 0.75 mg/l and 10 mg/l, respectively, were used to identify a PJI the sensitivity and specificity were 57% and 100%, respectively.

CONCLUSIONS

Serum D-Dimer showed a good sensitivity but a poor specificity for the diagnosis of shoulder PJI. Combination D-Dimer and CRP led to improvement of the specificity, however, at the cost of sensitivity. Thus, combination of both methods may be used as a confirmatory test in the diagnosis of shoulder PJI but not to rule out infection.

LEVEL OF EVIDENCE

Diagnostic level II.

What is the concordance rate of preoperative synovial fluid aspiration and intraoperative biopsy in detecting periprosthetic joint infection of the shoulder?

BACKGROUND

The accuracy of preoperative synovial fluid culture for microbe detection in shoulder periprosthetic joint infection (PJI) is poorly described. To evaluate the utility of preoperative culture data for early pathogen identification for shoulder PJI, we determined the concordance between preoperative synovial fluid culture results and intraoperative tissue culture results.

METHODS

Fifty patients who met the 2014 Musculoskeletal Infection Society criteria for shoulder PJI between January 2016 and December 2019 were retrospectively reviewed for clinical and demographic data. This cohort of patients was divided into 2 groups based on the concordance between preoperative and intraoperative culture results. The pathogens identified on preoperative and intraoperative cultures were classified as high-virulence or low-virulence. Student's t tests and Mann-Whitney U tests were used as appropriate for continuous variables, and χ² and Fisher's exact tests were used as appropriate for categorical variables.

RESULTS

Concordance between preoperative aspiration and intraoperative tissue culture was identified in 28 of 50 patients (56%). Preoperative cultures positive for Gram-positive species were more likely to be concordant than discordant (P = .015). Preoperative cultures positive for Cutibacterium acnes were more likely to be concordant with intraoperative cultures (P = .022). There were more patients with polymicrobial infection in the discordant group compared with the concordant group (P < .001). No statistically significant correlation between the preoperative serum C-reactive protein level and the intraoperative category of bacteria was reported. Staphylococcus aureus and coagulase-negative Staphylococci were associated with high specificity and negative predictive value. Preoperative cultures positive for C. acnes demonstrated sensitivity, specificity, positive predictive value, and negative predictive value lower than 0.8. Gram-negative pathogens demonstrated the highest sensitivity (1) and specificity (1), whereas polymicrobial infections exhibited the lowest sensitivity and positive predictive value.

CONCLUSION

Preoperative synovial fluid aspiration for shoulder PJI poorly predicts intraoperative culture results, with a discordance of 44%. More favorable concordance was observed for monomicrobial preoperative cultures, particularly for Gram-negative organisms and methicillin-sensitive S. aureus. The overall high rate of discordance between preoperative and intraoperative culture may prompt surgeons to base medical and surgical management on patient history and other factors and avoid relying solely on preoperative synovial fluid culture data.

Cutibacterium recovered from deep specimens at the time of revision shoulder arthroplasty samples has increased biofilm-forming capacity and hemolytic activity compared with Cutibacterium skin isolates from normal subjects

BACKGROUND

Biofilm formation and hemolytic activity are factors that may correlate with the virulence of Cutibacterium. We sought to compare the prevalence of these potential markers of pathogenicity between Cutibacterium recovered from deep specimens obtained at the time of surgical revision for failed shoulder arthroplasty and Cutibacterium recovered from skin samples from normal subjects.

METHODS

We compared 42 deep-tissue or explant isolates with 43 control Cutibacterium samples obtained from skin isolates from normal subjects. Subtyping information was available for all isolates. Biofilm-forming capacity was measured by inoculating a normalized amount of each isolate onto a 96-well plate. Planktonic bacteria were removed, the remaining adherent bacteria were stained with crystal violet, the crystal violet was re-solubilized in ethyl alcohol, and biofilm-forming capacity was quantitated by optical density (OD). Hemolytic activity was measured by plating a normalized amount of isolate onto agar plates. The area of the colony and the surrounding area of blood lysis were measured and reported as minimal, moderate, or severe hemolysis.

RESULTS

Biofilm-forming capacity was significantly higher in the tissue and explant samples compared with the control skin samples (OD of 0.34 ± 0.30 for deep tissue vs. 0.20 ± 0.28 for skin, P = .002). Hemolytic activity was also significantly higher in the tissue and explant samples than in the control skin samples (P < .0001). Samples with hemolytic activity had significantly higher biofilm-forming capacity compared with samples without hemolytic activity (OD of 0.27 ± 0.29 vs. 0.12 ± 0.15, P = .015). No difference in biofilm-forming capacity or hemolytic activity was found between subtypes.

CONCLUSIONS

Cutibacterium obtained from deep specimens at the time of revision shoulder arthroplasty has higher biofilm-forming capacity and hemolytic activity than Cutibacterium recovered from the skin of normal subjects. These data add support for the view that Cutibacterium harvested from deep tissues may have clinically significant virulence characteristics. The lack of correlation between these clinically relevant phenotypes and subtypes indicates that additional study is needed to identify genotypic markers that better correlate with biofilm and hemolytic activity.

The role of serum C-reactive protein in the diagnosis of periprosthetic shoulder infection

INTRODUCTION

There is a paucity of literature regarding serum C-reactive protein (CRP) in the evaluation of a shoulder periprosthetic joint infection (PJI). The purpose of the current study was to establish cutoff values for diagnosing shoulder PJI and evaluate the influence of the type of infecting microorganism and the classification subgroups according to last proposed International Consensus Meeting (ICM) criteria on the CRP level.

MATERIALS AND METHODS

A retrospective analysis of all 136 patients, who underwent septic or aseptic revision shoulder arthroplasty in our institution between January 2010 and December 2019, was performed. Shoulder PJI was defined according to the last proposed definition criteria of the ICM. Serum CRP levels were compared between infected and non-infected cases, between infection subgroups, as well as between different species of infecting microorganisms. A receiver-operating characteristic (ROC) analysis was performed to display sensitivity and specificity of serum CRP level for shoulder PJI.

RESULTS

A total of 52 patients (38%) were classified as infected, 18 meeting the criteria for definitive infection, 26 for probable infection and 8 for possible infection. According to the ROC curve, an optimized serum CRP threshold of 7.2 mg/l had a sensitivity of 69% and specificity of 74% (area under curve = 0.72). Patients with definitive infection group demonstrated significantly higher median serum CRP levels (24.3 mg/l), when compared to probable, possible infection groups and PJI unlikely group (8 mg/l, 8.3 mg/l, 3.6 mg/l, respectively, p < 0.05). The most common isolated microorganism was Cutibacterium acnes in 25 patients (48%) followed by coagulase-negative staphylococci (CNS) in 20 patients (39%). Patients with a PJI caused by high-virulent microorganisms had a significantly higher median serum CRP level compared to patients with PJI caused by low-virulent microorganisms (48 mg/l vs. 11.3 mg/l, p = 0.04).

CONCLUSIONS

Serum CRP showed a low sensitivity and specificity for the diagnosis of shoulder PJI, even applying cutoffs optimized by receiver-operating curve analysis. Low-virulent microorganisms and patients with probable and possible infections are associated with lower CRP levels compared to patients with definitive infection and infections caused by high-virulent microorganisms.

LEVEL OF EVIDENCE

Diagnostic Level III.

The role of implant sonication in the diagnosis of periprosthetic shoulder infection

BACKGROUND

The aim of this study was to investigate the validity of implant sonication fluid cultures in the diagnosis of shoulder periprosthetic joint infection (PJI) compared with tissue culture.

METHODS

This was a retrospective case-control study analyzing all patients who underwent a revision surgery for any kind of suspected septic or aseptic event due to failed shoulder arthroplasty at our institution between July 2014 and December 2018. The diagnostic validity of implant sonication was analyzed on the basis of the last proposed definition criteria of the International Consensus Meeting and compared with standard tissue cultures.

RESULTS

Of the 72 patients, a total of 28 (38.9%) were classified as infected. Of the 28 infected patients, 20 (71.4%) had an identified organism by tissue cultures, and Cutibacterium acnes was the most commonly isolated pathogen. The sensitivities of sonicate fluid (≥50 CFU/mL) and periprosthetic tissue culture for the diagnosis of periprosthetic shoulder infection were 36% and 61% (P = .016), and the specificities were 97.7% and 100% (P > .99), respectively. If no cutoff value was used in sonication culture, the sensitivity increased to 75% whereas the specificity dropped to 82%. Although there was no significant difference in sensitivity between tissue culture and the no-cutoff sonication fluid culture (61% vs. 75%, P = .125), the specificity of tissue culture was significantly higher (100% vs. 82%, P = .01).

CONCLUSION

Tissue culture showed a higher sensitivity and specificity than implant sonication in the diagnosis of shoulder PJI and should remain the gold standard for microbiological diagnosis of shoulder PJI.

Outcomes of revision surgery after periprosthetic shoulder infection: a systematic review

BACKGROUND

Periprosthetic shoulder infection (PSI) is one of the most challenging complications after shoulder arthroplasty. Different treatments have been proposed, but the best surgical procedure remains disputed in the current literature. This systematic review investigated the outcomes of revision surgery after PSI.

METHODS

The PubMed and Scopus databases were used to search keywords in April 2018. Of 2157 titles, 34 studies were finally analyzed. Demographics, laboratory and microbiological data, types of implants, surgical techniques with complications and reoperations, eradication rates, and clinical and functional outcomes were reported.

RESULTS

A total of 754 patients were identified. Cutibacterium acnes (C. acnes) was the most common microorganism found both in PSI (33%) and persistent infections (40%). Preoperatively, C-reactive protein was elevated in 70% of patients with PSI. Reverse shoulder arthroplasty had a lower prevalence of infection (P < .001). The eradication rate was 96% with 1 stage, 93% with permanent spacers, 86% with 2 stages, 85% with resection arthroplasty, and 65% with irrigation and débridement. One-stage revision was the best treatment, considering postoperative flexion and abduction, compared with resection arthroplasty, permanent spacers, and 2-stage revision. One-stage revision showed fewer postoperative complications than irrigation and débridement, resection arthroplasty, and 2-stage surgery. Two-stage surgery was the most common treatment, and the functional score demonstrated no differences between 2-stage and 1-stage procedures.

CONCLUSIONS

Our review suggests that a 1-stage procedure should be recommended to treat PSI. Two-stage revision could be reserved for select cases in which the bacterium involved is unknown.

permanent articulating antibiotic spacer in the treatment of periprosthetic shoulder infections

INTRODUCTION

Periprosthetic shoulder infections (PSIs) represent a serious complication following shoulder arthroplasty. No consensus exists regarding the optimal option. We conducted a retrospective case-control study to compare the outcomes of 2-stage revision shoulder arthroplasty and those of definitive articulating antibiotic spacer implantation with regards to eradication of the infection, improvement of pain and shoulder function.

MATERIALS AND METHODS

Thirty patients treated for an infected shoulder arthroplasty were retrospectively reviewed after a mean follow-up of 8 years (range, 2-10 years). Nineteen underwent definitive articulating antibiotic spacer implantation and 11 underwent 2-stage revision arthroplasty. Mean age at surgery was 68.8 years. Assessment included Constant-Murley score, visual analog scale pain score, objective examination, patient subjective satisfaction score as well as standard radiographs.

RESULTS

At the most recent follow-up, none of the patients had clinical or radiographic signs suggesting recurrent infection. Most patients reported satisfying subjective and objective outcomes. Follow-up examination showed significant improvement of all variables compared to preoperative values (p<0.001). Radiographs did not show progressive radiolucent lines or change in the position of the functional spacer. No statistically significant differences were reported between the two groups concerning Constant-Murley and VAS scores, while average forward flexion and abduction were significantly higher in patients undergoing 2-stage revision surgery.

CONCLUSIONS

Both surgical procedures provided infection eradication and satisfying subjective functional outcomes. Functional results were superior in patients treated with revision shoulder prosthesis, although a higher rate of complication was reported in this cohort of patients, thus suggesting the use of permanent spacer in high-risk or low-demanding elderly patients.

LEVEL OF EVIDENCE

III, Retrospective case-control study.

Management of periprosthetic shoulder infections with the use of a permanent articulating antibiotic spacer

INTRODUCTION

Management of periprosthetic shoulder infections (PSIs) still remains challenging. We conducted a retrospective case study to assess the outcomes of definitive articulating antibiotic spacer implantation in a cohort of elderly, low-demanding patients. We hypothesized that in patients with low functional demands seeking pain relief with chronic PSIs, treatment with a definitive articulating antibiotic spacer would lead to satisfying results concerning eradication of the infection, improvement of pain, and improving shoulder function.

MATERIALS AND METHODS

19 patients underwent definitive articulating antibiotic spacer implantation for the treatment of an infected shoulder arthroplasty. Mean age at surgery was 70.2 years. Patients were assessed pre-operatively with functional assessment including Constant-Murley score, and objective examination comprehending ROM, visual analog scale pain score, and patient subjective satisfaction (excellent, good, satisfied, or unsatisfied) score. Radiographs were taken to examine signs of loosening, and change in implant positioning.

RESULTS

At the most recent follow-up, none of the patients had clinical or radiographic signs suggesting recurrent infection. Most patients reported satisfying subjective and objective outcomes. Follow-up examination showed significant improvement of all variables compared to pre-operative values (p < 0.001). Radiographs did not show progressive radiolucent lines or change in the position of the functional spacer. In one case, glenoid osteolysis was reported, which did not affect the clinical outcome.

CONCLUSIONS

In selected elderly patients with low functional demands seeking pain relief with infected shoulder arthroplasty, definitive management with a cement spacer is a viable treatment option that helps in eradicating shoulder infection and brings satisfying subjective and objective outcomes.

LEVEL OF EVIDENCE

Case series, Level IV.