Outcome Following Debridement, Antibiotics, and Implant Retention in Hip Periprosthetic Joint Infection-An 18-Year Experience

Perioperative Demographic and Laboratory Characteristics of Failed DAIR: Can We Determine Which Patients Will Fail?

INTRODUCTION

Debridement, antibiotics, and implant retention (DAIR) are the mainstays surgical treatment for acute periprosthetic joint infection (PJI). However, re-operation following DAIR is common, and the risk factors for DAIR failure remain unclear. This study aimed to assess the perioperative characteristics of patients who failed initial DAIR treatment.

METHODS

A retrospective review was conducted on 83 patients who underwent DAIR for acute PJI within three months following index surgery from 2011 to 2022, with a minimum one-year follow-up. Surgical outcomes were categorized using the Musculoskeletal Infection Society (MSIS) outcome reporting tool (Tiers 1 to 4). Patient demographics, laboratory data, and perioperative outcomes were compared between patients who had failed (Tiers 3 and 4) (n = 32) and successful (Tiers 1 and 2) (n = 51) DAIR treatment. Logistic regression was also performed.

RESULTS

After logistic regression, Charlson Comorbidity Index (CCI) (odds ratio (OR): 1.57; P = 0.003), preoperative C-reactive protein (CRP) (OR: 1.06; P = 0.014), synovial white blood cell (WBC) (OR: 1.14; P = 0.008), and polymorphonuclear cell (PMN%) counts (OR: 1.05; P = 0.015) were independently associated with failed DAIR. Compared with total hip arthroplasty (THA), total knee arthroplasty (TKA) patients (OR: 6.08; P = 0.001) were at increased risk of DAIR failure. The type of organism and time from primary surgery were not correlated with DAIR failure.

CONCLUSION

Patients who had failed initial DAIR tended to have significantly higher CCI, CRP, synovial WBC, and PMN%. The TKA DAIRs were more likely to fail than the THA DAIRs. These characteristics should be considered when planning acute PJI management, as certain patients may be at higher risk for DAIR failure and may benefit from other surgical treatments.

Diagnosis and Management of Infected Total Ankle Replacements

As the number of primary total ankle replacements increases for treatment of end-stage ankle arthritis, failures are also expected to rise. Periprosthetic joint infection is among the causes of failures and has been reported to be as high as 5%. Diagnosis is usually made by a combination of clinical examination findings, imaging, laboratory, and microbiological workup. Management is generally separated into limb salvage or amputation. Limb salvage can be challenging and may involve a single versus staged approach. Options include revision arthroplasty or arthrodesis procedures (ankle versus tibiotalocalcaneal), and a multidisciplinary approach is sought to eradicate infection before definitive management.

Lower Rates of Reoperation Following Partial or Complete Revision Arthroplasty Compared to Debridement, Antibiotics, and Implant Retention for Early Postoperative and Acute Hematogenous Periprosthetic Hip Infection

BACKGROUND

This study aimed to: 1) compare treatment outcomes between debridement, antibiotics, and implant retention (DAIR) and partial or complete revision arthroplasty (RA) for early postoperative and acute hematogenous total hip arthroplasty periprosthetic joint infection (PJI) and 2) identify factors associated with treatment outcome.

METHODS

The study consisted of a retrospective cohort of patients who underwent surgery for PJI between 2004 and 2021. There were 76 patients (74.5%) who underwent DAIR and 26 patients (25.5%) who underwent RA. Treatment success was defined as treatment eradication at a minimum of a 2-year follow up. Bivariate regression analysis was used to assess the effect of different factors on treatment outcomes. Kaplan-Meier survivorship was performed to compare survivorship between cohorts.

RESULTS

At a mean follow-up of 8.2 years (range, 2.2 to 16.4), significantly more DAIR failed treatment (DAIR, 50 [65.8%]; 10 [38.5%]; P = .015). The 8-year Kaplan-Meier survivorship was 35.1% [95% confidence interval (CI), 24.3 to 45.9] for patients treated with DAIR and 61.5% [95% CI, 42.9 to 80.1] for those treated with RA (log rank = 0.039). Bivariate regression analysis showed performing a RA was associated with a higher likelihood of treatment success (odds ratio 4.499, 95% CI 1.600 to 12.647, P = .004), whereas a higher body mass index was associated with treatment failure (odds ratio 0.934, 95% CI 0.878 to 0.994, P = .032).

CONCLUSIONS

To reduce the rate of recalcitrant infection following early postoperative or acute hematogenous total hip arthroplasty PJI, RA may be of benefit over DAIR. This is especially relevant in the early postoperative period, when components can be readily exchanged.

Clinical Outcomes After Revision Hip Arthroplasty due to Prosthetic Joint Infection-A Single-Center Study of 369 Hips at a High-Volume Center With a Minimum of One Year Follow-Up

BACKGROUND

Prosthetic joint infection (PJI) treatment decisions are traditionally based on treatment algorithms. There is, however, a lack of evidence to support the choice of these treatment algorithms. Therefore, we aimed to assess the one-year survival after PJI revision and compared different surgical strategies in a single-center setting.

METHODS

Revisions of the hip due to PJI performed at our institution between January 2008 and September 2021 with at least one-year of follow-up were identified. In total, 134 debridement, antibiotics, and implant retentions (DAIRs), 114 one-stage revisions, and 121 two-stage revisions were performed. Infections were classified as early, acute hematogenous, and chronic. Survival was calculated using the Kaplan-Meier method and cumulative incidence function. Predictors of outcomes were examined with Fine-Gray regressions and Cox proportional hazards regressions. Subdistribution hazard ratios and hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated.

RESULTS

At one-year follow-up, 26.6% (CI 22.2 to 31.2%) of the patients had undergone reoperation and 7.9% (CI 5.4 to 10.9%) had died. The risk for reoperation was highest after DAIR (36.6%, CI 28.5 to 44.7%) and lowest after one-stage revision (20.2%, CI 13.4 to 28%). Within the early infections, the one-stage revision almost halved the risk of reoperation (HR 0.51, CI 0.31 to 0.84) with no added mortality risk (HR 1.05, CI 0.5 to 2.2), when compared to DAIR.

CONCLUSION

By utilizing 1-stage revision over DAIR in early infections, it might be possible to improve the prognosis by decreasing the risk of reoperation without increasing mortality. However, as the patient selection is undeniably difficult, more research is warranted.

The outcomes of acute periprosthetic joint infection following unicompartmental knee replacement managed with early debridement, Antibiotics, and implant retention

BACKGROUND

Periprosthetic joint infection (PJI) following unicompartmental knee replacement (UKR) is an uncommon, yet serious, complication. There is a paucity of evidence regarding the effectiveness of Debridement-Antibiotics-and-Implant-Retention (DAIR) in this setting. The aim of this study is to investigate the effectiveness of DAIR for acute UKR PJI.

METHOD

Between 2006 and 2019, 5195 UKR were performed at our institution. Over this period, sixteen patients underwent DAIR for early, acute PJI. All patients met MSIS PJI diagnostic criteria. The median age at DAIR was 67 years (range 40-73) and 12 patients were male (75.0%). The median time to DAIR was 24 days (range 6-60). Patients were followed up for a median of 6.5 years (range1.4-10.5) following DAIR.

RESULTS

0.3% (16/5195) of UKR in our institution had a DAIR within 3 months. 15 of 16 patients (93.8%) were culture positive, with the most common organism MSSA (n = 8, 50.0%). Patients were treated with an organism-specific intravenous antibiotic regime for a median of 6 weeks, followed by oral antibiotics for a median duration of 6 months. The Kaplan-Meier survivor estimate for revision for PJI was 57% (95%CI: 28-78%) at five years, and survivor estimate for all cause revision 52% (95%CI: 25-74%).The median Oxford Knee Score for patients with a viable implant at final follow-up was 45 points (range 39-46).

CONCLUSION

Early, acute PJI after UKR is rare. DAIR had a moderate success rate, with infection-free survivorship of 57% at 5 years. Those successfully treated with DAIR had excellent functional outcome and implant survival.

Successful Implant Retention in a Chronified Hematogenous Bilateral Periprosthetic Hip Joint Infection With Enterococcus faecalis

We present a case with bilateral hematogenous hip periprosthetic joint infection with Enterococci which could be treated successfully with implant retention despite chronification and partial loosening. A debridement and replacement of the modular components was carried out with replacement of a loose acetabular cup on the right side. Considering poor local infection control, antibiotic treatment was enhanced by local application of vancomycin. In the present case, treatment of chronic enterococcal periprosthetic joint infection while preserving the implants was successful despite unfavorable odds. Considering the duration of infection, causative microorganism, and loosening of one of the implants, staged exchange of both hip replacements would have been the standard procedure. This case illustrates that some concepts have to be challenged from time to time.

What Is the Most Effective Treatment for Periprosthetic Joint Infection After Total Joint Arthroplasty in Patients with Rheumatoid Arthritis?: A Systematic Review

BACKGROUND

Rheumatoid arthritis (RA) is a risk factor for periprosthetic joint infection (PJI) after total joint arthroplasty (TJA). The purpose of this study was to perform a systematic review comparing the failure rates of debridement, antibiotics, and implant retention (DAIR), one-stage exchange arthroplasty/revision (OSR), and 2-stage exchange arthroplasty/revision (TSR) for RA patients with PJI and identify risk factors in the RA population associated with increased treatment failure rate.

METHODS

PubMed, Ovid MEDLINE, and Ovid Embase databases were screened with the terms "rheumatoid arthritis," "total joint arthroplasty," "prosthetic joint infection," and "treatment for PJI" on August 29, 2021. Four hundred ninety-one studies were screened, of which 86 were evaluated. The primary outcome evaluated was failure of surgical treatment for PJI.

RESULTS

Ten retrospective cohort studies were included after full-text screening, yielding 401 patients with RA. Additional demographic and PJI management data were obtained for 149 patients. Patients with RA who underwent TSR demonstrated a lower failure rate (26.8%) than both DAIR (60.1%) and OSR (39.2%) (χ2 = 37.463, p < 0.00001). Patients with RA who underwent DAIR had a 2.27 (95% CI, 1.66-3.10) times higher risk of experiencing treatment failure than those who underwent TSR. Among risk factors, there was a significant difference in the C-reactive protein of patients who did vs. did not experience treatment failure (p = 0.02).

CONCLUSION

TSR has a higher rate of success in the management of PJI patients with RA compared with DAIR and OSR. The complete removal of the infected prosthesis and delayed reimplantation may lower the treatment failure rate.

LEVEL OF EVIDENCE

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

Debridement, antibiotics and implant retention (DAIR) following hip and knee arthroplasty: results and findings of a multidisciplinary approach from a non-specialist prosthetic infection centre

INTRODUCTION

Prosthetic joint infection (PJI) is a catastrophic complication following arthroplasty surgery. Recently a debridement, antibiotics and implant retention (DAIR) procedure has gained popularity for PJI where a thorough debridement, irrigation and modular component exchange is undertaken.

METHOD

We present the outcome for DAIR, data collected prospectively, in a busy orthopaedic unit but not one specialising in PJI. All patients with PJI were included without loss of data or patients from 2012 to 2018 with a minimum follow-up of 5 years.

RESULTS

Four total knee replacements, 17 total hip replacements, one revision total hip replacement and three hip hemiarthroplasties are included with an average duration from onset of symptoms to the DAIR procedure of 11 days (range 1-22 days). Staphylococcus aureus (24%) and Staphylococcus epidermidis (32%) were the most common causative organisms, and the most common antibiotic regimens included intravenous teicoplanin and flucloxacillin. Average follow-up was 67 months (range 9-104 months). Only four patients went on to require revision surgery. An analysis of midterm patient outcome measures for 6 of the total hip replacement (THR) DAIR patients were compared with a database of 792 THRs (with a minimum two-year follow-up) carried out by the same surgeon revealed no significant difference in Oxford hip scores at one-year post-surgery (OHS DAIR 36.2 vs 39 for control group).

CONCLUSION

This study includes 25 consecutive patients treated with DAIR with only one reinfection, with a mean follow-up period of 5 years. Using a strict protocol, DAIR appears to offer a successful treatment strategy for the management of early PJI.

Early Staphylococcal Periprosthetic Joint Infection (PJI) Treated with Debridement, Antibiotics, and Implant Retention (DAIR): Inferior Outcomes in Patients with Staphylococci Resistant to Rifampicin

It is unknown how rifampicin resistance in staphylococci causing a periprosthetic joint infection (PJI) affects outcomes after debridement, antibiotics, and implant retention (DAIR). We thus aimed to compare the risk of relapse in DAIR-treated early PJI caused by staphylococci with or without rifampicin resistance. In total, 81 patients affected by early PJI were included, and all patients were treated surgically with DAIR. This was repeated if needed. The endpoint of relapse-free survival was estimated using the Kaplan-Meier method, and Cox regression models were fitted to assess the risk of infection relapse for patients infected with rifampicin-resistant bacteria, adjusted for age, sex, type of joint, and type of index surgery. In patients with rifampicin-resistant staphylococci, relapse was seen in 80% after one DAIR procedure and in 70% after two DAIR procedures. In patients with rifampicin-sensitive bacteria, 51% had an infection relapse after one DAIR procedure and 33% had an infection relapse after two DAIR procedures. Patients with rifampicin-resistant staphylococcal PJI thus had an increased adjusted risk of infection relapse of 1.9 (95% CI: 1.1-3.6, p = 0.04) after one DAIR procedure compared to patients with rifampicin-sensitive bacteria and a 4.1-fold (95% CI: 1.2-14.1, p = 0.03) increase in risk of infection relapse after two DAIR procedures. Staphylococcal resistance to rifampicin is associated with inferior outcomes after DAIR. These findings suggest that DAIR may not be a useful strategy in early PJI caused by rifampicin-resistant staphylococci.

Rat model of recalcitrant prosthetic joint infection using biofilm inocula

Prosthetic joint infection (PJI) is a rare but devastating complication of joint arthroplasty. Biofilm formation around the prosthesis confers tolerance to antibiotics so that treatment is challenging. Most animal models of PJI use planktonic bacteria to establish the infection which fails to reproduce the pathology of chronic infection. We aimed to establish a rat model of Staphylococcus aureus PJI in male Sprague-Dawley rats using biofilm inocula and demonstrate its tolerance to frontline antibiotics. Pilot studies indicated that infection could be introduced to the knee joint by a biofilm-coated pin but that handling the prosthetic without disturbing the biofilm was difficult. We, therefore, developed a pin with a slotted end and used a miniature-biofilm reactor to develop mature biofilm in this niche. These biofilm-laden pins consistently produced infection of the bone and joint space. Treatment with high dose cefazolin, 250 mg/kg, starting the day of surgery reduced or cleared pin-adherent bioburden within 7 days, however when escalation from 25 to 250 mg/kg cefazolin treatment was delayed for 48 h, rats were unable to clear the infection. To track infections, we used bioluminescent bacteria, however, the bioluminescent signal did not accurately track the degree of infection in the bone and joint space as the signal did not penetrate the bone. In conclusion, we demonstrate that using a custom prosthetic pin, we can generate biofilm in a specific niche using a novel bioreactor setup and initiate a rat PJI that rapidly develops tolerance to supra-clinical doses of cefazolin.

Management of soft tissues in patients with periprosthetic joint infection

BACKGROUND

Appropriate soft tissue management represents a critical step in treating periprosthetic joint infection (PJI). This review discusses relevant guidelines that surgeons should follow in the management of soft tissues in PJI treatment. BODY: It is imperative for arthroplasty surgeons to thoroughly debride and rebuild soft tissue with a good blood supply. Relevant guidelines that surgeons should follow rigorously include preoperative evaluation of soft tissue status and plan-making, adequate surgical area exposure, intraoperative removal of all necrotic and infected soft tissues, adequate coverage of soft tissue defects, timely postoperative assessment and management of soft tissues, wound management and proper rehabilitation.

CONCLUSION

Soft tissue management plays a critical role in the treatment of PJI. To improve the infection control rate and postoperative joint function, surgeons should be familiar with these general principles and rigorously practice them in PJI management.

1.5-Stage Versus 2-Stage Exchange Total Hip Arthroplasty for Chronic Periprosthetic Joint Infections: A Comparison of Survivorships, Reinfections, and Patient-Reported Outcomes

BACKGROUND

Management of periprosthetic joint infection after total hip arthroplasty (THA) has traditionally consisted of a 2-stage approach. However, 1.5-stage exchange has garnered recent interest. We compared 1.5-stage to 2-stage exchange recipients. Specifically, we assessed (1) infection-free survivorship and risk factors for reinfection; (2) 2-year surgical/medical outcomes (eg, reoperations, readmissions); (3) Hip Disability and Osteoarthritis Outcome Scores for Joint Replacement (HOOS-JR); and (4) radiographic outcomes (ie, progressive radiolucent lines, subsidences, and failures).

METHODS

We reviewed a consecutive series of 1.5-stage or planned 2-stage THAs. A total of 123 hips were included (1.5-stage: n = 54; 2-stage: n = 69) with mean clinical follow-up of 2.5 years (up to 8 years). Bivariate analyses assessed incidences of medical and surgical outcomes. Additionally, HOOS-JR scores and radiographs were evaluated.

RESULTS

The 1.5-stage exchange had 11% greater infection-free survivorship at final follow-up compared to 2 stages (94% versus 83%, P = .048). Morbid obesity was the only independent risk factor demonstrating increased reinfection among both cohorts. No differences in surgical/medical outcomes were observed between groups (P = .730). HOOS-JR scores improved markedly for both cohorts (1.5-stage difference = 44.3, 2-stage difference = 32.5; P < .001). A total of 82% of 1.5-stage patients did not demonstrate progressive femoral or acetabular radiolucencies, while 94% of 2-stage recipients did not have femoral radiolucencies and 90% did not have acetabular radiolucencies.

CONCLUSION

The 1.5-stage exchange appeared to be an acceptable treatment alternative for periprosthetic joint infections after THAs with noninferior infection eradication. Therefore, this procedure should be considered by joint surgeons for treatment of periprosthetic hip infections.

Success of Debridement, Antibiotics, and Implant Retention in Prosthetic Joint Infection Following Primary Total Knee Arthroplasty: Results from a Prospective Multicenter Study of 189 Cases

BACKGROUND

This study aimed to identify the success rate of debridement, antibiotics, and implant retention (DAIR) for prosthetic joint infection (PJI) in a large prospective cohort of patients undergoing total knee arthroplasty (TKA). The ability for different PJI classification systems to predict success was assessed.

METHODS

Prospective data recorded in the Prosthetic Joint Infection in Australia and New Zealand Observational (PIANO) study was analyzed. 189 newly diagnosed knee PJIs were managed with DAIR between July 2014 and December 2017. Patients were prospectively followed up for 2 years. A strict definition of success was used, requiring the patient being alive with documented absence of infection, no ongoing antibiotics and the index prosthesis in place. Success was compared against the Coventry (early PJI = ≤1 month), International Consensus Meeting (early = ≤90 days), Auckland (early = <1 year), and Tsukayama (early = ≤1 month, hematogenous = >1 month with <7 days symptoms, chronic = >1 month with >7 days symptoms) classifications.

RESULTS

DAIR success was 45% (85/189) and was highest in early PJIs defined according to the Coventry (adjusted odds ratio [aOdds Ratio (OR)] = 3.9, P=0.01), the ICM (aOR = 3.1, p=0.01), and the Auckland classifications (aOR = 2.6, P=0.01). Success was lower in both hematogenous (aOR = 0.4, P=0.03) and chronic infections (aOR = 0.1, P=0.003).

CONCLUSION

Time since primary TKA is an important predictor of DAIR success. Success was highest in infections occurring <1 month of the primary TKA and progressively decreased as time since the primary TKA increased.

Principles of mechanical and chemical debridement with implant retention

BACKGROUND

Periprosthetic joint infection (PJI) is one of the most common causes of early revision for total hip and knee arthroplasty. Mechanical and chemical debridement typically referred to as debridement, antibiotics, and implant retention (DAIR) can be a successful technique to eradicate PJI in acute postoperative or acute hematogenous infections. This review will focus specifically on the indications, techniques, and outcomes of DAIR.

DISCUSSION

The success of mechanical and chemical debridement, or a DAIR operation, is reliant on a combination of appropriate patient selection and meticulous technique. There are many technical considerations to take into consideration. One of the most important factors in the success of the DAIR procedure is the adequacy of mechanical debridement. Techniques are surgeon-specific and perhaps contribute to the large variability in the literature on the success of DAIR. Factors that have been shown to be associated with success include the exchange of modular components, performing the procedure within seven days or less of symptom onset, and possibly adjunctive rifampin or fluoroquinolone therapy, though this remains controversial. Factors that have been associated with failure include rheumatoid arthritis, age greater than 80 years, male sex, chronic renal failure, liver cirrhosis, and chronic obstructive pulmonary disease.

CONCLUSIONS

DAIR is an effective treatment option for the management of an acute postoperative or hematogenous PJI in the appropriately selected patient with well-fixed implants.

Implant retention with serial debridement and use of antibiotic-loaded calcium sulfate beads in acute fracture-related infection (FRI) after pelvic ring or acetabular fractures: A retrospective case series of 7 cases

BACKGROUND

The development of a pelvic wound infection in the presence of hardware after open reduction and internal fixation presents a clinical dilemma and there is little literature to aid in decision-making. The purpose of this study was to describe the possibility of debridement, antibiotic pearls and retention of the implant (DAPRI) procedure to eradicate the infection.

METHODS

Tumor-like debridement, antibiotic pearls and retention of the implant (DAPRI) aimed to remove the biofilm allowing a higher and prolonged local antibiotic concentration by using calcium sulfate antibiotic-added beads. Wound status, radiological signs of bone healing, gait and functional activity of the patient were evaluated.

RESULTS

Seven patients underwent this technique. The mean follow up time was nine months (range: 6 -16 months). Complete wound healing was achieved in all the patients with no major complications. Average time of bony union was 4.3 months (range: 3-6 months) with no need for implant removal.

CONCLUSION

The DAPRI technique might represent a safe and more conservative treatment for management of early fracture-related infections (FRI) of the pelvis and acetabulum.

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.

Dislocation After Debridement, Antibiotics, and Implant Retention for Periprosthetic Joint Infections of the Hip

BACKGROUND

Debridement, antibiotics, and implant retention (DAIR) is a common treatment option for hip periprosthetic joint infection (PJI). However, noninfectious outcomes of DAIR such as instability are not well reported. The purpose of this study was to evaluate risk factors for hip dislocation post-DAIR for PJI of both primary and revision total hip arthroplasty (THA).

METHODS

A retrospective chart review identified all patients who underwent DAIR of a primary or revision THA over a 20-year period with a minimum 1-year follow-up. A total of 151 patients met inclusion criteria, 19.9% of whom had a post-DAIR dislocation. Demographic and intraoperative variables were obtained. Patients who had modular components exchanged during DAIR to those with increased offset, increased "jump distance", or a more stable acetabular liner were defined as patients who had "components exchanged to increase stability." Predictors of hip dislocation post-DAIR were inserted into a multivariate linear regression.

RESULTS

Post-DAIR dislocation rates were 16.3% in primary THAs and 25.4% in revision THAs. In patients who had "components exchanged to increase stability" during hip DAIR, there was at least an 11-fold reduction (1/odds ratio (OR), 0.09) in dislocation risk compared to patients who had no components altered during modular component exchange during hip DAIR (OR, 0.09; 95% confidence interval, 0.02-0.44; P < .001), while a 13-fold increased dislocation risk was seen in patients with a history of neuromuscular disease (OR, 13.45; 95% confidence interval, 1.73-104.09; P = .01).

CONCLUSIONS

During DAIR of hip PJI, surgeons should consider prophylactically exchanging components to increase stability even if components appear stable intraoperatively.

Early failure of a highly cross-linked polyethylene inlay after total hip arthroplasty probably due to insufficient irradiation

Highly cross-linked polyethylene (XLPE) is a major advance in total hip arthroplasty (THA), as it suffers from less wear and thus is associated with lower revision rates than standard ultra-high molecular weight polyethylene. Early failures are reported rarely, and associated with specific design or manufacturing issues. We report a case requiring early revision due to adverse reaction to polyethylene particles. Investigations identified insufficient irradiation as the most probable cause of failure. Here are reported the features of a clinical case with determination of the material properties of the retrieved XLPE liner and establishment of the appropriate calibration curves as reference. Periprosthetic joint infection could be ruled out with appropriate sampling as cause for the inflammatory periarticular tumour. Histology identified a massive macrophagic reaction to micrometric polyethylene particles. No component malposition was present, nor any third-body wear. The trans-vinylene index (TVI) indicated insufficient and potentially detrimental irradiation of the polyethylene, while gel content, crystallinity, melting temperature and oxidation index remained within expected ranges. Histologically proven failure of a XLPE THA liner was identifiable despite correct implantation of the components. The cause of failure most probably was an inadequate irradiation, as indicated by determination of the TVI. This case underscores the importance of histologic workup even in aseptic revisions, and of detailed analysis of retrievals. The calibration curves provided are essential for analysis of other retrievals.

Periprosthetic joint infection following hip hemiarthroplasty : factors associated with infection and treatment outcome

AIMS

The aims of this study were to determine the incidence and factors for developing periprosthetic joint infection (PJI) following hemiarthroplasty (HA) for hip fracture, and to evaluate treatment outcome and identify factors associated with treatment outcome.

METHODS

A retrospective review was performed of consecutive patients treated for HA PJI at a tertiary referral centre with a mean 4.5 years' follow-up (1.6 weeks to 12.9 years). Surgeries performed included debridement, antibiotics, and implant retention (DAIR) and single-stage revision. The effect of different factors on developing infection and treatment outcome was determined.

RESULTS

A total of 1,984 HAs were performed during the study period, and 44 sustained a PJI (2.2%). Multiple logistic regression analysis revealed that a higher CCI score (odds ratio (OR) 1.56 (95% confidence interval (CI) 1.117 to 2.187); p = 0.003), peripheral vascular disease (OR 11.34 (95% CI 1.897 to 67.810); p = 0.008), cerebrovascular disease (OR 65.32 (95% CI 22.783 to 187.278); p < 0.001), diabetes (OR 4.82 (95% CI 1.903 to 12.218); p < 0.001), moderate-to-severe renal disease (OR 5.84 (95% CI 1.116 to 30.589); p = 0.037), cancer without metastasis (OR 6.42 (95% CI 1.643 to 25.006); p = 0.007), and metastatic solid tumour (OR 15.64 (95% CI 1.499 to 163.087); p = 0.022) were associated with increasing PJI risk. Upon final follow-up, 17 patients (38.6%) failed initial treatment and required further surgery for HA PJI. One-year mortality was 22.7%. Factors associated with treatment outcome included lower preoperative Hgb level (97.9 g/l (SD 11.4) vs 107.0 g/l (SD 16.1); p = 0.009), elevated CRP level (99.1 mg/l (SD 63.4) vs 56.6 mg/l (SD 47.1); p = 0.030), and type of surgery. There was lower chance of success with DAIR (42.3%) compared to revision HA (66.7%) or revision with conversion to total hip arthroplasty (100%). Early-onset PJI (≤ six weeks) was associated with a higher likelihood of treatment failure (OR 3.5 (95% CI 1.2 to 10.6); p = 0.007) along with patients treated by a non-arthroplasty surgeon (OR 2.5 (95% CI 1.2 to 5.3); p = 0.014).

CONCLUSION

HA PJI initially treated with DAIR is associated with poor chances of success and its value is limited. We strongly recommend consideration of a single-stage revision arthroplasty with cemented components.Cite this article: Bone Jt Open 2022;3(12):924-932.

The Cost-Effectiveness of Extended Oral Antibiotic Prophylaxis for Infection Prevention After Total Joint Arthroplasty in High-Risk Patients

BACKGROUND

Extended oral antibiotic prophylaxis may decrease rates of prosthetic joint infection (PJI) after total joint arthroplasty (TJA) in patients at high risk for infection. However, the cost-effectiveness of this practice is not clear. In this study, we used a break-even economic model to determine the cost-effectiveness of routine extended oral antibiotic prophylaxis for PJI prevention in high-risk TJA patients.

METHODS

Baseline PJI rates in high-risk patients, the cost of revision arthroplasty for PJI, and the costs of extended oral antibiotic prophylaxis regimens were obtained from the literature and institutional purchasing records. These variables were incorporated in a break-even economic model to calculate the absolute risk reduction (ARR) in infection rate necessary for extended oral antibiotic prophylaxis to be cost-effective. ARR was used to determine the number needed to treat (NNT).

RESULTS

Extended oral antibiotic prophylaxis with Cefadroxil in patients at high risk for PJI was cost-effective at an ARR in baseline infection rate of 0.187% (NNT = 535) and 0.151% (NNT = 662) for TKA and THA, respectively. Cost-effectiveness was preserved with varying costs of antibiotic regimens, PJI treatment costs, and infection rates.

CONCLUSION

The use of extended oral antibiotic prophylaxis may reduce PJI rates in patients at high risk for infection following TJA and appears to be cost-effective. However, the current evidence supporting this practice is limited in quality. The use of extended oral antibiotic prophylaxis should be weighed against the possible development of future antimicrobial resistance, which may change the value proposition.

Management of Periprosthetic Joint Infections After Hemiarthroplasty of the Hip: A Critical Analysis Review

➢

Periprosthetic joint infection (PJI) following hip hemiarthroplasty (HA) is a devastating complication, incurring immense health-care costs associated with its treatment and placing considerable burden on patients and their families. These patients often require multiple surgical procedures, extended hospitalization, and prolonged antimicrobial therapy.

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Notable risk factors include older age, higher American Society of Anesthesiologists (ASA) score, inadequate antibiotic prophylaxis, non-antibiotic-loaded cementation of the femoral implant, longer duration of the surgical procedure, and postoperative drainage and hematoma.

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Although the most frequent infecting organisms are gram-positive cocci such as Staphylococcus aureus, there is a higher proportion of patients with gram-negative and polymicrobial infections after hip HA compared with patients who underwent total hip arthroplasty.

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Several surgical strategies exist. Regardless of the preferred surgical treatment, successful management of these infections requires a comprehensive surgical debridement focused on eradicating the biofilm followed by appropriate antibiotic therapy.

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A multidisciplinary approach led by surgeons familiar with PJI treatment and infectious disease specialists is recommended for all cases of PJI after hip HA to increase the likelihood of treatment success.

Symptom duration is associated with failure of periprosthetic joint infection treated with debridement, antibiotics and implant retention

Background

Debridement, antibiotics, and implant retention (DAIR) is an alternative treatment strategy for periprosthetic joint infection (PJI). However, no consensus exists regarding which patient population(s) may be most suitable for DAIR. This study aims to investigate the overall infection control rate and explore the prognostic factors associated with acute, hematogenous, and chronic PJIs treated with DAIR.

Methods

We retrospectively reviewed the included patients who were diagnosed with PJI and underwent DAIR at two institutions from 2009 to 2018 (n = 104). We collected the clinical data, including demographics, preoperative laboratory tests, Charlson Comorbidity Index, surgical information, and culture organism results. Treatment success was defined according to the criteria reported by Diaz-Ledezma. All patients were followed for at least one year unless failure preceded that time point. A multivariable analysis was utilized to identify prognostic factors associated with treatment, and a Kaplan-Meier survival analysis was used to depict the infection control rate.

Results

The overall treatment success rate in the current cohort of patients was 67.3% at a median 38.6 (interquartile range: 23.5, 90.7) months follow-up. Patients with a duration of infectious symptoms of more than ten days were more likely to fail (P = 0.035, hazard ratio 8.492, 95% confidence interval 1.159–62.212). There was no difference among acute, hematogenous, and chronic infections in terms of failure rate (P = 0.161).

Conclusions

DAIR is a reasonable treatment option for PJI, and its use in the setting of chronic infection does not appear to be a contraindication. Performing DAIR within ten days of the presentation of symptoms had a higher rate of treatment success.

Skeletal infections: microbial pathogenesis, immunity and clinical management

Osteomyelitis remains one of the greatest risks in orthopaedic surgery. Although many organisms are linked to skeletal infections, Staphylococcus aureus remains the most prevalent and devastating causative pathogen. Important discoveries have uncovered novel mechanisms of S. aureus pathogenesis and persistence within bone tissue, including implant-associated biofilms, abscesses and invasion of the osteocyte lacuno-canalicular network. However, little clinical progress has been made in the prevention and eradication of skeletal infection as treatment algorithms and outcomes have only incrementally changed over the past half century. In this Review, we discuss the mechanisms of persistence and immune evasion in S. aureus infection of the skeletal system as well as features of other osteomyelitis-causing pathogens in implant-associated and native bone infections. We also describe how the host fails to eradicate bacterial bone infections, and how this new information may lead to the development of novel interventions. Finally, we discuss the clinical management of skeletal infection, including osteomyelitis classification and strategies to treat skeletal infections with emerging technologies that could translate to the clinic in the future.

Outcomes of Debridement, Antibiotics and Implant Retention (DAIR) for Periprosthetic Joint Infection in a High-Volume Arthroplasty Centre

PURPOSE

Prosthetic joint infection (PJI) following total knee arthroplasty (TKA) and total hip arthroplasty (THA) can be a devastating diagnosis. Debridement, antibiotics and implant retention (DAIR) is a preferred treatment modality for acute PJI. A retrospective analysis of infected primary arthroplasties to evaluate the success of DAIR and factors influencing its outcomes.

METHODS

We retrospectively reviewed all patients who underwent DAIR for PJI at our unit between 2010 and 2018. Patients who underwent revision surgery as an index procedure, arthroscopic washout and those with less than two years of follow-up were excluded. Treatment failure was defined as revision arthroplasty for recurrence of infection within 2 years of the index procedure. Chi-square and Fischer's exact test were used to compare between patient factors and DAIR outcomes. Kaplan-Meier survival curve and log-rank test were used to analyse implant survivorship following DAIR.

RESULTS

Of the sixty patients (40 knees, 20 hips) who underwent DAIR, eighteen (13 knees, 5 hips) required revision arthroplasty within 2 years accounting for a success rate of 70%. Predictive factors for revision were American Society of Anaesthesiologist (ASA) score of greater than 2 (p = 0.021), BMI > 35 (p = 0.046), C Reactive protein (CRP) > 200 mg/L (p = 0.007) and Staphylococcus aureus growth (p = 0.012). The five-year survival rate for DAIR was 70%, which remained constant after two years from DAIR.

CONCLUSION

Success rate of DAIR in PJI was 70% which was comparable to similar studies in the literature. ASA > 2, BMI > 35, CRP > 200 and staphylococcus aureus growth were predictors for DAIR failure. Implant survival rate and duration were better following DAIR in early-onset PJI.

External validation study of hip peri-prosthetic joint infection with cemented custom-made articulating spacer (CUMARS)

INTRODUCTION

Peri-prosthetic joint infection (PJI) is a devastating complication after total hip arthroplasty (THA). The use of custom-made articulating spacers (CUMARS) has been described for use in the first of 2-stage treatment. We report our outcomes of managing PJI using CUMARS.

METHODS

Patients undergoing 1st-stage revision using the Exeter standard stem, all-polyethylene acetabulum and antibiotic-loaded cement were identified. Medical records were assessed for demographics, microbiological and operative treatment, complications, eradication of infection and reoperations. No postoperative restrictions were enforced. 2nd-stage revision was undertaken in the presence of pain or subsidence.

RESULTS

53 patients underwent 1st-stage revision using this technique. The average follow-up was 3.9 (range 0.5-7.2) years. Infection was eradicated in 47 (88.7%) patients. 2 patients had chronic infection managed with suppressive antibiotics, 2 patients died before eradication confirmed, 1 patient had raised inflammatory markers but no positive aspiration cultures, 1 patient was lost to follow-up. Complications occurred in 5 (9.4%) patients - 4 dislocations and 1 infected haematoma. 4 patients required a repeated 1st stage. 2nd-stage revision was performed in 19 patients (35%).

CONCLUSIONS

The CUMARS technique is an effective way of eradicating PJI after THA. It maintains function by providing a stable construct that permits weight-bearing. It delays or negates the need for 2nd-stage revision. Furthermore, it allows surgeons to choose between managing patients prospectively as a single-stage revision with the option of reverting to a 2nd stage.

Can "domino" therapy effectively treat the infection around the prosthesis after the limb salvage surgery of bone tumor? - A study of sequential therapy

BACKGROUND

Tumor resection and prosthetic replacement have become the treatments of choice for malignant bone tumors. Infections are the leading cause of failure of limb salvage surgeries. Therefore, treating infections around prostheses after limb salvage is essential and challenging. Our research team designed a "domino" sequential treatment plan to treat postoperative infections around tumor prostheses and evaluated its efficacy.

PURPOSE

To introduce the new domino sequential treatment plan for postoperative infections of tumor prostheses, and evaluate the technical points of the plan and prognosis in medium- and long-term follow-ups.

METHODS

Between January 2015 and August 2021, 14 patients were treated with prosthesis-preserving domino sequential therapy for peripheral prosthesis infections after bone-tumor limb salvage. The sample included eight cases of distal femur tumor, two of proximal tibia tumor, three of pelvic tumor, and one of middle femur tumor. We evaluated routine blood test results, C-reactive protein level, the erythrocyte sedimentation rate, and other indicators. X-rays and CT scans of the surgical site were obtained and the Musculoskeletal Tumor Society (MSTS) score was calculated. Treatment involved debridement and lavage of the prosthesis, and systemic and local antibiotics.

RESULTS

The positivity rate of microbial culture was 78.6%. There were three cases of Staphylococcus aureus, one of Staphylococcus epidermidis, two of methicillin-resistant Staphylococcus epidermidis, one of methicillin-resistant Staphylococcus aureus, two of Acinetobacter baumannii, one of Streptococcus lactis (group C), one of Streptococcus mitis, and three with negative cultures. In three cases, sequential treatment failed to control the infection. The operation success rate was 78.6% (11/14). One case eventually required amputation, and another required long-term wound dressings. To control the infection, a third had to be treated using antibiotic bone cement combined with the "intramedullary nail reverse double insertion" technique. The MSTS scores of patients before infection debridement and at the last follow-up showed statistically significant differences (t = 5.312, p = 0.02).

CONCLUSIONS

The prosthesis-preserving domino sequential method has certain advantages for treating bone-tumor limb salvage infections around the prosthesis.

LEVEL OF EVIDENCE

Level IV, therapeutic.

Risk Factors of DAIR Failure and Validation of the KLIC Score: A Multicenter Study of Four Hundred Fifty-Five Patients

Background: Debridement, antibiotic agents, and implant retention (DAIR) is a currently accepted approach for the treatment of early prosthetic joint infections (PJI). The success of a DAIR procedure has shown variable results throughout the published literature. Scoring systems such as the Kidney, Liver, Index surgery, Cemented prosthesis, and C-reactive protein value (KLIC) score for the selection of patients that are likely to benefit from DAIR have proved to be helpful in decision making. Our study aims to further validate the KLIC score using a large external multicentric cohort and to evaluate other risk factors for failure. Patients and Methods: A retrospective analysis of patients with an early acute PJI who were treated with DAIR and recorded in a database of eight Spanish university hospitals was performed. According to pre-operative variables of the KLIC study, patients were categorized into five groups: group A, ≤2 points; group B, 2.5-3.5 points; group C, 4-5 points; group D, 5.5-6.5 points; and group E, ≥7 points. Failure rates were compared between groups at 60 days and after 60 days of DAIR. Further variables for risk of failure were also analyzed. Results: A total of 455 patients with early acute PJI were included in the analyses. At 60 days, patients presenting with pre-operative elevated C-reactive protein serum levels, Staphylococcus aureus, and polymicrobial infections were associated with failure. Failure rates recorded were 12% for group A (n = 210), 18% for group B (n = 83), 26% for group C (n = 89), 24% for group D (n = 66), and 0% for group E (n = 7). Univariable analysis between consecutive groups of the KLIC score showed no differences for failure before 60 days of the DAIR procedure. Scheduled surgery and having the procedure performed by a specialized unit were also identified as important factors for DAIR success. Conclusions: Our results suggest the KLIC score was not useful for predicting failure in our cohort. Furthermore, our results indicate a specialized unit should conduct DAIR procedures.

The Clinical Outcome of Different Total Knee Arthroplasty Designs in One-Stage Revision for Periprosthetic Infection

BACKGROUND

Despite the growing number of studies reporting on the best surgical treatment in the management of periprosthetic joint infection, there are no robust data regarding the type of infected prosthesis before any kind of exchange arthroplasty. To overcome these shortcomings, we asked the following questions: (1) What is the survivorship of nonhinged and hinged knee implants after one-stage exchange arthroplasty and (2) what is the functional outcome after one-stage exchange procedure focusing on knee prostheses and the type of prior infected knee implant. In a secondary radiographic analysis, we also investigated if (3) the type of femoral bone morphology measured by the inner femoral diameter influences the rate of aseptic failures also in patients with periprosthetic joint infection.

METHODS

Between January 2011 and December 2017, we performed a retrospective designed study including 211 patients with infected knee prostheses. After all, seventy-six percent (161 of 211 patients) were available for final data analysis. These patients were divided into four groups as per the performed implant revision: (1) bicondylar total knee arthroplasty to rotating hinge implant, (2) rotating hinge to rotating hinge implant, (3) rotating hinge to full hinge implant, and (4) full hinge to full hinge implant. The mean follow-up (FU) was six years (range 3 to 9; standard deviation = 1.9), whereas a minimum FU of three years was required for inclusion. Survivorship and group analysis were performed, and the functional outcome was assessed using postoperative Oxford Knee Scores at the latest FU (60-point scale with lower scores representing less pain and greater function). Furthermore, in all cases, femoral bone morphology was determined as per the Citak classification system.

RESULTS

At the final FU, the overall surgical revision rate was 23% (37/161 patients) with nine percent (15/161 patients) suffering a periprosthetic joint infection relapse. Group 1 consisted of 51, group 2 consisted of 67, group 3 consisted of 24, and group 4 consisted of 19 patients. The lowest overall revision rate was found in group 2 (16%, n = 11), compared with 28% (n = 14) in group 1, 29% (n = 7) in group 3, and 26% (n = 5) in group 4; however, no significant differences were found (P = .902). The functional outcome (Oxford Knee Score) was clinically constant in all groups, with 32 points in group 1, 37 points in group 2, 33 points in group 3, and 35 points in group 4 (P = .107). Concerning the number of patients with aseptic loosening as per bone morphology, 74% (14/19) of all aseptic loosening cases appeared in femoral bone type C morphologies according to Citak (75% in group 1, 56% in group 2, 100% in group 3, and 100% in group 4).

CONCLUSIONS

The results obtained suggest a generally high overall revision rate (25%) with a good infection control rate (91%). Although we were unable to work out a specific group of patients with a statistically significant differing outcome, it is interesting to see that hinged implants can reach more or less the same functional outcome and revision rates as nonhinged implants, when it comes to revision surgeries. In this study, a relatively high number of aseptic failures contributed to a high overall revision rate. In this context, the bone morphology, measured as per the Citak classification system, could be confirmed as a risk factor for aseptic failures also in septic patients. Therefore, further research might focus on revision knee implant design.

Local antibiotic treatment with calcium sulfate as carrier material improves the outcome of debridement, antibiotics, and implant retention procedures for periprosthetic joint infections after hip arthroplasty – a retrospective study

Abstract. Purpose: Debridement, antibiotics, and implant retention (DAIR) is an established treatment modality in periprosthetic joint infections (PJIs), but success rates vary. This study compared the success of DAIR for PJIs after a total hip arthroplasty (THA), with or without local antibiotic delivery with CaSO4 as the carrier material. Methods: A retrospective review of DAIR for PJIs after THA performed between 2010 and 2018, including 41 patients is conducted. A total of 27 patients were treated by DAIR with local antibiotics with CaSO4 as the carrier material, and 14 patients were treated by a standard DAIR. The endpoints were treatment failure, defined as the need for a reoperation, either a second DAIR or a prosthesis removal or exchange due to persistent or recurrent infection, the initiation of a long-term suppressive antibiotic treatment, or death related to infection. Results: Considering any reoperation as an outcome, 11 of 14 cases treated without AB-CaSO4 (79 %) and 4 of the 27 cases treated with AB-CaSO4 failed (15 %). Considering revision as an outcome, 9 out of 14 cases treated without AB-CaSO4 (64 %) and 4 of the 27 cases treated with AB-CaSO4 (15 %) failed. A Kaplan–Meier survival analysis showed that local antibiotic delivery with CaSO4 as the carrier material led to a significantly longer infection-free survival, considering any surgical revision (p<0.0001; hazard ratio 8.9 (95 % CI 2.8–28.2)) or revision with component exchange (p=0.0015; hazard ratio 5.6 (95 % CI 1.7–18.2)) as the endpoint. Conclusion: The addition of local antibiotics with CaSO4 as the carrier material to DAIR for PJIs after THA significantly increases success rates, such as infection-free survival, any reoperation, and revision with component exchange in particular.

Management strategies for prosthetic joint infection: long-term infection control rates, overall survival rates, functional and quality of life outcomes

DAIR (debridement, antibiotics, and implant retention), one-stage and two-stage revision surgery are the most common management strategies for prosthetic joint infection (PJI) management. Our knowledge concerning their efficacy is based on short to medium-term low-quality studies.

Most studies report infection recurrence rates or infection-free time intervals. However, long-term survival rates of the infection-free joints, functional and quality of life outcome data are of paramount importance.

DAIR, one-stage and two-stage revision strategies are not unique surgical techniques, presenting several variables. Infection control rates for the above strategies vary from 75% to 90%, but comparisons are difficult because different indications and patient selection criteria are used in each strategy.

Recent outcome data show that DAIR and one-stage revision in selected patients (based on host, bacteriological, soft tissue and type of infection criteria) may present improved functional and quality of life outcomes and reduced costs for health systems as compared to those of two-stage revision.

It is expected that health system administrators and providers will apply pressure on surgeons and departments towards the wider use of DAIR and one-stage revision strategies. It is the orthopaedic surgeon’s responsibility to conduct quality studies in order to fully clarify the indications and outcomes of the different revision strategies.

Cite this article: EFORT Open Rev 2021;6:727-734. DOI: 10.1302/2058-5241.6.210008

Short-term results of treatment of staphylococcal periprosthetic hip joint infection with combined antibiotics and bacteriophages treatment

Infectious complications after primary implantation of the hip joint are 0.5–3 %, and in the case of re-endoprosthetics, the risk of periprosthetic infection can reach 30 %. Also, we should not forget about the high percentage (16–20 %) of recurrence of periprosthetic infection of the hip joint, which leads to an unsatisfactory result of treatment up to amputation of a limb or even death of the patient. The reasons for the recurrence of the infectious process can be antibiotic resistance and antibiotic tolerance of microorganisms, as well as the ability of microorganisms to form biofilms on implants. In this regard, there is a constant need to search for alternative means of antimicrobial therapy, as well as to select the optimal ways of their delivery and deposition, which is of practical importance when performing surgical interventions in traumatology and orthopedics to protect the implantable structure from possible infection of the surgical site. One of the methods currently available to combat bacterial infections acquired antibiotic resistance and antibiotic tolerance is the use of natural viruses that infect bacterial bacteriophages. The above suggests a more effective suppression of periprosthetic infection, including persisters that deviate from antibiotics. It is, as a rule, associated with biofilms if used in conjunction with antibiotics and phages, when the use of bacteriophages predetermines the effectiveness of treatment. With the use of sensitive bacteriophages in the treatment of periprosthetic infections, a significant (p = 0.030) reduction in the rate of recurrence of infection (from 31 to 4.5 %) was observed. The use of lytic bacteriophages in traumatology and orthopedics is of great interest for phagotherapy of infections caused by antibiotic-resistant and biofilm-forming strains of bacteria. A clinical study using a single-stage surgical revision with simultaneous application of antibiotics and phages in the treatment of deep periprosthesis infection of the hip joint endoprosthesis, followed by 12 months follow-up for periprosthetic infection recurrence, demonstrated the effectiveness of the use of combined antibiotic and bacteriophages treatment.

What Are the Long-term Outcomes of Mortality, Quality of Life, and Hip Function after Prosthetic Joint Infection of the Hip? A 10-year Follow-up from Sweden

BACKGROUND

Prosthetic joint infection (PJI) is a complication after arthroplasty that negatively affects patient health. However, prior reports have not addressed the long-term consequences of hip PJI in terms of patient mortality, quality of life, and hip function.

QUESTIONS/PURPOSES

At a minimum of 10 years after PJI in patients undergoing primary THA, in the context of several large, national databases in Sweden, we asked: (1) Is mortality increased for patients with PJI after THA compared with patients with a noninfected THA? (2) Does PJI of the hip have a negative influence on quality of life as measured by the Euro-QoL-5D-5L (EQ-5D-5L), ambulatory aids, residential status, and hip function as measured by the Oxford Hip Score (OHS)? (3) Which factors are associated with poor patient-reported outcome measures (PROMs) for patients with PJI after primary THA?

METHODS

This study included 442 patients with a PJI after primary THA, from a previously published national study, including all patients with a THA performed from 2005 to 2008 in Sweden (n = 45,570) recruited from the Swedish Hip Arthroplasty Registry (SHAR). Possible deep PJIs were identified in the Swedish Dispensed Drug Registry and verified by review of medical records. Mortality in patients with PJI was compared with the remaining cohort of 45,128 patients undergoing primary THA who did not have PJI. Mortality data were retrieved from the SHAR, which in turn is updated daily from the population registry. A subgroup analysis of patients who underwent primary THA in 2008 was performed to adjust for the effect of comorbidities on mortality, as American Society of Anesthesiologists (ASA) scores became available in the SHAR at that time. For the PROM analysis, we identified three controls matched by age, gender, indication for surgery, and year of operation to each living PJI patient. A questionnaire including EQ-5D-5L, ambulatory aids, residential status, and OHS was collected from patients with PJI and controls at a mean of 11 years from the primary procedure. Apart from age and gender, we analyzed reoperation data (such as number of reoperations and surgical approach) and final prosthesis in situ to explore possible factors associated with poor PROM results.

RESULTS

After controlling for differences in sex, age, and indication for surgery, we found the all-cause 10-year mortality higher for patients with PJI (45%) compared with patients undergoing THA without PJI (29%) (odds ratio 1.4 [95% CI 1.2 to 1.6]; p < 0.001). The questionnaire, with a minimum of 10 years of follow-up, revealed a lower EQ-5D-5L index score (0.83 versus 0.94, -0.13 [95% CI -0.18 to -0.08; p < 0.001]), greater proportion of assisted living (21% versus 12%, OR 2.0 [95% CI 1.2 to 3.3]; p = 0.01), greater need of ambulatory aids (65% versus 42%, OR 3.1 [95% 2.1 to 4.8]; p < 0.001), and a lower OHS score (36 versus 44, -5.9 [-7.7 to -4.0]; p < 0.001) for patients with PJI than for matched controls. Factors associated with lower OHS score for patients with PJI were three or more reoperations (-8.0 [95% CI -13.0 to -3.2]; p = 0.01) and a direct lateral approach used at revision surgery compared with a posterior approach (-4.3 [95% CI -7.7 to -0.9]; p = 0.01).

CONCLUSION

In this study, we found that PJI after THA has a negative impact on mortality, long-term health-related quality of life, and hip function. Furthermore, the subgroup analysis showed that modifiable factors such as the number of reoperations and surgical approach are associated with poorer hip function. This emphasizes the importance of prompt, proper initial treatment to reduce repeated surgery to minimize the negative long-term effects of hip PJI.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Adherence to a reliable PJI diagnostic protocol minimizes unsuspected positive cultures rate

Background

The aim of the present study was to evaluate the incidence of unsuspected PJI when prosthetic revisions are thoroughly evaluated by PJI dedicated orthopedic surgeon before surgery. The hypothesis is that the incidence of unsuspected PJI is reduced by applying this protocol.

Methods

This is a historical cohort study carried out in one university hospital. The prosthetic revision assessment was carried out in January 2019. From that date on, all patients that were programmed for hip or knee revision (either by an orthopedic surgeon specialized or not in septic revisions) were scheduled for a preoperative visit with the same orthopedic surgeon specialized in septic revisions. The diagnostic algorithm applied was based on the Pro-Implant Foundation diagnostic criteria. Prior to the revision assessment, the indication for joint aspiration was done at the surgeons’ discretion (non-specialized in septic revisions) and the preoperative identification of PJI was also done by a hip or knee surgeon (not specialized in septic surgery).

Results

Based on the PIF criteria, there were 15 infections among the revisions in group 1 and 18 PJI in group 2 (p > 0.05). The most interesting finding was that there were 7 patients with unsuspected positive cultures in group 1. That represents 11% of all revisions. No patient in group 2 was found with unsuspected positive cultures (p < 0.001).

Conclusion

A thorough PJI diagnostic algorithm should be implemented before prosthetic revision to avoid unsuspected positive cultures.

Is Negative Pressure Wound Therapy with Instillation Suitable for the Treatment of Acute Periprosthetic Hip Joint Infection?

Background: Periprosthetic joint infection (PJI) can be devastating for the patient and demanding for the surgeon. In acute PJI, attempts are made to retain the prosthesis by debridement of the infected tissue, targeted antibiotic therapy and an exchange of modular components with implant retention (DAIR). There has been sparse research with adjunctive negative pressure wound treatment with wound irrigation (NPWTI) on the treatment outcome. Questions/purposes: The goal was to assess the efficacy of our protocol of DAIR with adjunctive NPWTI in acute PJI and to reduce the need for later additional DAIR and Irrigation and Debridement (I and D). Patients and Methods: Our cohort of 30 patients (31 hips) with acute PJI was divided into two groups based on symptom presentation up to 6 weeks or >6 weeks from prior (index) surgery (acute early or acute late groups, respectively). All received DAIR with an exchange of modular components and NPWTI with polyhexanide instillation, with the goal of bacterial elimination and biofilm elimination. Postoperatively, the patients were followed up clinically and radiographically for a mean of 4.3 years. Results: Of the 31 PJI hips, 19 were early acute and 12 were late acute. In total, 21 hips had no evidence of residual infection, 10 required further surgical revision: 1 due to dislocation and 9 due to infection. Of these nine, seven had a removal of all the components and two were treated with irrigation and debridement (I and D), with the demise of one patient from pneumonia shortly after the procedure. The Kaplan–Meier 60-month revision free implant survival from infection was 73.2% (CI: 58.9–91.0%) and at the final follow up, the mean Harris Hip Score (HHS) was 81.1 ± 11.8 and the mean WOMAC score was 33.3 ± 20.1. Conclusions: Our results are in line with those reported in prior studies. However, the utility of our protocol is inconclusive and needs further evaluation based on our small cohort and the lack of a control group. Level of Evidence: IV.

A Coxoperitoneal Shunt as Salvage for a Recurrent Giant Seroma of the Hip After Periprosthetic Joint Infection: A Case Report

CASE

A giant seroma developed in the hip of a 44-year-old man after resection arthroplasty performed for recurrent periprosthetic joint infection (PJI). The seroma persisted despite joint reconstruction but was ultimately treated successfully by internal drainage through a coxoperitoneal shunt.

CONCLUSION

Resection arthroplasty of the hip is considered a salvage procedure for failed implant retention in the situation of persistent PJI. Nevertheless, functional results are poor and further soft-tissue complications may occur. A giant seroma of the hip may be drained into the peritoneal cavity, permitting healing without risking contamination from external, percutaneous drainage.

The James A. Rand Young Investigator's Award: Are Intraoperative Cultures Necessary If the Aspiration Culture Is Positive? A Concordance Study in Periprosthetic Joint Infection

BACKGROUND

The concordance between preoperative synovial fluid culture and multiple intraoperative tissue cultures for identifying pathogenic microorganisms in periprosthetic joint infection (PJI) remains unknown. Our aim is to determine the diagnostic performance of synovial fluid culture for early organism identification.

METHODS

A total of 363 patients who met Musculoskeletal Infection Society criteria for PJI following primary total joint arthroplasty were identified from a retrospective joint infection database. Inclusion criteria required a positive preoperative intra-articular synovial fluid sample within 90 days of intraoperative tissue culture(s) at revision surgery. Concordance was defined as matching organism(s) in aspirate and intraoperative specimens.

RESULTS

Concordance was identified in 279 (76.8%) patients with similar rates among total hip arthroplasties (77.2%) and total knee arthroplasties (76.4%, P = .86). Culture discordance occurred in 84 (23.1%) patients; 37 (10.2%) had no intraoperative culture growth and 33 (90.1%) were polymicrobial. Monomicrobial Staphylococcal PJI cases had high sensitivity (0.96, 95% confidence interval [CI] 0.92-0.98) and specificity (0.85, 95% CI 0.80-0.90). Polymicrobial infections had the lowest sensitivity (0.06, 95% CI 0.01-0.19).

CONCLUSION

Aspiration culture has favorable sensitivity and specificity when compared to tissue culture for identifying the majority of PJI organisms. Clinicians can guide surgical treatment and postoperative antibiotics based on monomicrobial aspiration results, but they should strongly consider collecting multiple tissue cultures to maximize the chance of identifying an underlying polymicrobial PJI.

LEVEL OF EVIDENCE

Level III.

Outcome of Irrigation and Debridement With Topical Antibiotics Delivery for the Management of Periprosthetic Joint Infection Occurring Within 3 Months Since the Primary Total Joint Arthroplasty

BACKGROUND

Irrigation and debridement with modular component exchange is appealing for surgeons to treat early-stage periprosthetic joint infection (PJI). However, the indication, perioperative protocol, and success rate remain controversial. This study is the first one to present results of debridement, antibiotics, and implant retention (DAIR) with integrated MIT (modular component exchange, povidone-iodine and topical antibiotics delivery) protocol for treating PJI occurring within 3 months since the primary total joint arthroplasty.

METHODS

We retrospectively analyzed patients who received DAIR with MIT protocol in our department between January 2011 and May 2018. Topical antibiotics were delivered in all cases. Topical antibiotics infusion was applied for those infected with multidrug-resistant bacteria, fungus, polymicrobial infection, and culture negative one. Failure was defined as additional surgical intervention for infection after DAIR; persistent sinus tract, drainage or excessive joint pain; need for suppressive antibiotics therapy due to the infection; infection relapse with the same pathogen; reinfection with different microorganism; and infection-related death.

RESULTS

A total of 73 patients with a mean age of 63.30 ± 10.97 years were included in this study, including 43 men and 30 women. There are 41 knees and 32 hips. Thirty patients had sinus tract. With a mean follow-up of 63.79 ± 18.57 months, there were 9 failures in total with an overall success rate of 87.67%. The success rate was 88.57% and 86.84% for those receiving topical antibiotics infusion postoperatively and those without.

CONCLUSIONS

DAIR with a standard MIT protocol is a viable and safe option for PJI occurring within 3 months since the primary total joint arthroplasty.

LEVEL OF EVIDENCE

Level 4, therapeutic study.

Management of peri-prosthetic joint infection and severe bone loss after total hip arthroplasty using a long-stemmed cemented custom-made articulating spacer (CUMARS)

Background

There is little evidence on techniques for management of peri-prosthetic infection (PJI) in the context of severe proximal femoral bone loss. Custom-made articulating spacers (CUMARS) utilising cemented femoral stems as spacers was described providing better bone support and longer survival compared to conventional articulating spacers. We retrospectively report our experience managing PJI by adaptation of this technique using long cemented femoral stems where bone loss precludes use of standard stems.

Methods

Patients undergoing 1st stage revision for infected primary and revision THA using a cemented long stem (> 205 mm) and standard all-polyethylene acetabulum between 2011 and 2018 were identified. After excluding other causes of revision (fractures or aseptic loosening), Twenty-one patients remained out of total 721 revisions. Medical records were assessed for demographics, initial microbiological and operative treatment, complications, eradication of infection and subsequent operations. 2nd stage revision was undertaken in the presence of pain or subsidence.

Results

Twenty-one patients underwent 1st stage revision with a cemented long femoral stem. Mean follow up was 3.9 years (range 1.7–7.2). Infection was eradicated in 15 (71.4%) patients. Two patients (9.5%) required repeat 1st stage and subsequently cleared their infection. Three patients (14.3%) had chronic infection and are on long term suppressive antibiotics. One patient (4.8%) was lost to follow up before 2 years. Complications occurred in seven patients (33%) during or after 1st stage revision. Where infection was cleared, 2nd stage revision was undertaken in 12 patients (76.5%) at average of 9 months post 1st stage. Five (23.8%) CUMARS constructs remained in-situ at an average of 3.8 years post-op (range 2.6–5.1).

Conclusions

Our technique can be used in the most taxing of reconstructive scenarios allowing mobility, local antibiotic delivery, maintenance of leg length and preserves bone and soft tissue, factors not afforded by alternative spacer options.

Debridement, antibiotics and implant retention (DAIR): An effective treatment option for early prosthetic joint infections

INTRODUCTION

Debridement, antibiotics and implant retention (DAIR) is an attractive treatment option for prosthetic joint infections (PJIs). However, reported success rates and predictors of DAIR failure vary widely. The primary aim of this study is to report the outcome of DAIR in patients with hip and knee PJIs receiving short course of antibiotic therapy. The secondary aim is to identify risk factors for DAIR failure.

METHODS

We performed a retrospective analysis of prospectively collected data of all hip and knee PJIs consecutively diagnosed at Quadrante Orthopedic Center, an Italian orthopedic hospital highly specialized in prosthetic surgery, from January 1, 2013 to January 1, 2019, and we analyzed those treated with DAIR.

RESULTS

Forty-seven PJIs occurred after 5102 arthroplasty procedures. Twenty-one patients (45%) aged 71 years were treated with DAIR for hip (62%) and knee (38%) PJIs. These were classified as early PJIs in 76% cases, delayed in 19% and late in 5%. Median time from PJI-related symptoms onset to implant revision surgery was 12 days (IQR, 7-20 days). The median duration of antibiotic treatment after surgery was 63 days (IQR, 53-84 days). Sixteen (76%) patients were cured after a median follow-up of 2197 days (IQR, 815-2342 days), while 5 (24%) experienced failure. At multivariate analysis, delayed/late PJIs were significantly associated with failure (OR = 12.51; 95% CI 1.21-129.63, p = 0.03).

CONCLUSIONS

DAIR represents an effective strategy for the treatment of early PJIs in spite of short course of antibiotic therapy.

Distinct vasculotropic versus osteotropic features of S. agalactiae versus S. aureus implant-associated bone infection in mice

Osteomyelitis is a devastating complication of orthopaedic surgery and commonly caused by Staphylococcus aureus (S. aureus) and Group B Streptococcus (GBS, S. agalactiae). Clinically, S. aureus osteomyelitis is associated with local inflammation, abscesses, aggressive osteolysis, and septic implant loosening. In contrast, S. agalactiae orthopaedic infections generally involve soft tissue, with acute life-threatening vascular spread. While preclinical models that recapitulate the clinical features of S. aureus bone infection have proven useful for research, no animal models of S. agalactiae osteomyelitis exist. Here, we compared the pathology caused by these bacteria in an established murine model of implant-associated osteomyelitis. In vitro scanning electron microscopy and CFU quantification confirmed similar implant inocula for both pathogens (~10⁵ CFU/pin). Assessment of mice at 14 days post-infection demonstrated increased S. aureus virulence, as S. agalactiae infected mice had significantly greater body weight, and fewer CFU on the implant and in bone and adjacent soft tissue (p < 0.05). X-ray, µCT, and histologic analyses showed that S. agalactiae induced significantly less osteolysis and implant loosening, and fewer large TRAP⁺ osteoclasts than S. aureus without inducing intraosseous abscess formation. Most notably, transmission electron microscopy revealed that although both bacteria are capable of digesting cortical bone, S. agalactiae have a predilection for colonizing blood vessels embedded within cortical bone while S. aureus primarily colonizes the osteocyte lacuno-canalicular network. This study establishes the first quantitative animal model of S. agalactiae osteomyelitis, and demonstrates a vasculotropic mode of S. agalactiae infection, in contrast to the osteotropic behavior of S. aureus osteomyelitis.

Methods and probability of success after early revision of prosthetic joint infections with debridement, antibiotics and implant retention

Prosthetic joint infection (PJI) is a rare-and dreaded-complication of arthroplasty requiring multidisciplinary care. Given the dual goal of treating the infection and maintaining satisfactory function, it is preferable to determine how and when the implanted components can be retained. Bacteria and fungi organize themselves into biofilms that shield them from antibiotics and the immune system. This biofilm is in place after 15 days of active infection. Some antibiotics have a better activity on biofilms. The following factors have a negative impact on the probability of a successful debridement, antibiotics and implant retention (DAIR) intervention: fracture or revision, use of cement, bacteremia, kidney and/or liver failure, immunosuppression and elevated CRP. Hematogenous infections have a worse prognosis than early postoperative infections. Using a decision algorithm increases the chances of DAIR being successful. The KLIC score applies to early postoperative infections (<4 weeks postoperative and<3 weeks from the first signs) while the CRIME-80 score applies to hematogenous infections (<3 weeks from the first signs). Arthroscopic treatments have no role here, whereas DAIR through an arthrotomy is well standardized. Wide spectrum antibiotic therapy, secondarily adapted to the causative microorganism, is indicated for a total of 3 months. The results against the infection are mixed, although following a decision algorithm resolves the infection in about 75% of cases. The functional outcomes and quality of life are close to those of patients who have undergone primary joint replacement. It is not recommended to carry out a second DAIR if the first one fails. It is logical to apply the principles set out for the hip and knee to other joint replacements, and to use the same algorithm. For the upper limb, and especially for reverse shoulder arthroplasty, one must be careful about Cutibacterium acnes infections as they are hard to diagnose. Surgeons should not hesitate to contact a referral center for any PJI, although it is preferable that early infections be treated at the facility that performed the implantation.

Success Rates of Debridement, Antibiotics, and Implant Retention in 230 Infected Total Knee Arthroplasties: Implications for Classification of Periprosthetic Joint Infection

BACKGROUND

Prosthetic joint infection (PJI) is the most common cause of failure following total knee arthroplasty (TKA). This study aimed to determine the success of debridement, antibiotics, and implant retention (DAIR) in a large cohort of TKA PJIs and assess the utility of current classification systems in predicting DAIR outcomes in early postoperative, late hematogenous, and chronic PJIs.

METHODS

In a multicenter review over 15 years, 230 patients underwent DAIR for first episode PJI following primary TKA. Patient demographics, disease and surgical factors, treatment regime, and outcomes were identified. Univariate and multivariate survival analyses were performed to identify factors associated with successful DAIR. Continuous variables with predictive value were further analyzed using receiver operating characteristic curves. The ability to predict DAIR outcomes of multiple classification systems was also assessed.

RESULTS

Patients were followed for an average of 6.9 years. The overall success rate of DAIR was 53.9%. On receiver operating characteristic analysis, 3 months (area under the curve = 0.63) and 1-year age (area under the curve = 0.66) of implant cut-offs was similarly predictive of outcomes. On multivariate survival analysis, DAIR was successful in 64% of "early" PJIs (implant <1 year) vs 38% of "late hematogenous" PJIs (implant >1 year; odds ratio [OR] 1.78, P = .01). For late PJIs (implant >1 year), Staphylococcus aureus (OR 4.70, P < .001) and gram-negative infections (OR 2.56, P = .031) were risk factors for DAIR failure.

CONCLUSION

DAIR has a high failure rate in all PJIs occurring more than a year post primary TKA, particularly when caused by S aureus or gram-negative bacteria. The age of implant is an important predictor of DAIR outcomes.

Risk factors affect success rate of debridement, antibiotics and implant retention (DAIR) in periprosthetic joint infection

Background

Periprosthetic joint infection (PJI) is the most devastating complication of joint replacement that seriously affects the quality of life and causes a heavy burden to the families and society. Due to shorter hospital stays, lower costs, improved joint function and less morbidity, a process of debridement, antibiotics and implant retention (DAIR) is recommended as the preferred treatment for acute periprosthetic joint infection. However, the factors that impact the success rate of DAIR remain controversial. This article evaluates the influential factors of DAIR and provides insights for orthopaedics surgeons to make optimal decisions to improve the success rate of DAIR.

Conclusion

The poor general condition of patients, high preoperative C-reactive protein (CRP) level, repeated joint surgeries, and Methicillin-resistant Staphylococcus aureus (MRSA) infections may be associated with lower DAIR success rate. To the contrary, early surgery, radical debridement, exchange of removable components, washing with iodine and vacuum sealing drainage (VSD) may improve the success rate of DAIR. A sinus tract may not be absolutely contraindicated, but surgeons should treat it with caution. As there is no consensus on many issues, more high-quality research is required.

Debridement, antibiotics and implant retention (DAIR) for the management of knee prosthetic joint infection

BACKGROUND

While two-stage revision arthroplasty is viewed as the gold standard for the treatment of knee periprosthetic joint infection (PJI) in terms of infection eradication, it is associated with significant cost along with patient morbidity and mortality. Debridement, antibiotics, and implant retention (DAIR) is an attractive option as it has demonstrated better patient outcomes, comparable implant longevity to primary arthroplasty, and significantly reduced cost when successful. Given the heterogeneity of what is defined as a DAIR the literature is highly variable in terms of its efficacy from the perspective of infection eradication.

METHODS

In the setting of a previously well-functioning, well-fixed arthroplasty with an acceptable soft tissue envelope and a treatable organism we report our methods for proceeding with a DAIR procedure, both unicompartmental and total knee.

RESULTS

With the above methods we have demonstrated improved patient outcomes when compared to one- or two-stage arthroplasty with lower patient morbidity. Implant longevity in the setting of a successful DAIR is equivalent to those of a primary arthroplasty.

CONCLUSIONS

With appropriate indications and good surgical technique as described we believe DAIR is an excellent option in the treatment of periprosthetic joint infection. We hope that with a well-defined protocol as outlined we can gain a better understanding of the efficacy of DAIR procedure with more homogeneity to the procedure to better define when they are most successful while improving patient outcomes and reducing cost.

Open Debridement is Superior to Arthroscopic Debridement for the Infected Total Knee Arthroplasty

BACKGROUND

Acutely infected total knee arthroplasty (TKA) is commonly treated with debridement, antibiotics, and implant retention (DAIR). There are no direct comparative studies to determine whether debridement should be performed open or arthroscopically for infected TKA. The aim of this study is to compare the outcomes of open vs arthroscopic debridement of infected TKAs.

METHODS

All patients at a university teaching hospital with an infected TKA treated with DAIR between 2002 and 2017 were analyzed. The primary outcome was successful treatment defined using international consensus criteria. Secondary outcomes included antibiotic suppression, prosthesis retention, mortality, postoperative range of motion, and length of stay. Clinical, laboratory, surgical, and antibiotic treatment data were collected. Propensity score matching was performed to control for selection bias.

RESULTS

DAIR was used in 141 patients. The initial DAIR procedure was open for 96 patients and arthroscopic for 45 patients. The success rate was 29% greater for open DAIR (45% open vs 16% arthroscopic; P < .001). After propensity score matching, this benefit was estimated to be 36% (95% confidence interval, 22%-50%; P < .0001). When those on antibiotic suppression were also considered successfully treated, open DAIR was still superior by 34% (95% confidence interval, 18%-51%; P < .0001).

CONCLUSION

For infected TKA, open DAIR is a more successful index procedure compared with arthroscopic DAIR. Open DAIR remained more successful even when antibiotic suppression is considered successful treatment.

Operative approach influences functional outcome after DAIR for infected total hip arthroplasty

Aims

To compare the functional outcome, health-related quality of life (HRQoL), and satisfaction of patients who underwent primary total hip arthroplasty (THA) and a single debridement, antibiotics and implant retention (DAIR) procedure for deep infection, using either the transgluteal or the posterior surgical approach for both procedures.

Methods

The study was registered at clinicaltrials.gov (ID: NCT03161990) on 15 May 2017. Patients treated with a single DAIR procedure for deep infection through the same operative approach as their primary THA (either the transgluteal or the posterior approach) were identified in the Norwegian Arthroplasty Register and given a questionnaire. Median follow-up after DAIR by questionnaire was 5.5 years in the transgluteal group (n = 87) and 2.5 years in the posterior approach group (n = 102).

Results

Patients in the posterior approach group were less likely to limp after the DAIR procedure (17% vs 36% limped all the time; p = 0.005), had a higher mean Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) function score (80 vs 71; p = 0.013), and were more likely to achieve a patient acceptable symptom state for the WOMAC function score (76% vs 55%; p = 0.002). In a multivariable analysis, the point estimate for the increase in WOMAC function score using the posterior approach was 10.2 (95% CI 3.1 to 17.2; p = 0.005), which is above the minimal clinically important improvement. The patients in the posterior approach group also reported better mean HRQoL scores and were more likely to be satisfied with their hip arthroplasty (77% vs 55%; p = 0.001).

Conclusion

In patients treated with a single, successful DAIR procedure for deep infection of a primary THA, the use of the posterior approach in both primary surgery and DAIR was associated with less limping, better functional outcome, better HRQoL, and higher patient satisfaction compared with cases where both were performed using the transgluteal approach. The observed differences in functional outcome and patient satisfaction were clinically relevant. Cite this article: Bone Joint J 2020;102-B(12):1662–1669.

Debridement, Antibiotics, and Implant Retention with the Direct Anterior Approach for Acute Periprosthetic Joint Infection Following Primary THA

Background:

Periprosthetic joint infection (PJI) is a devastating complication following total hip replacement. The direct anterior approach for total hip replacement is becoming increasingly popular. However, little is known about the success rate of treatment with debridement, antibiotics, and implant retention (DAIR) using the direct anterior approach. The aim of this study was to analyze the effectiveness of DAIR using this approach and identify patient and surgical factors that influence the results.

Methods:

Seventy-four patients (75 hips) in whom DAIR had been performed were identified from the records of the weekly multidisciplinary infection meeting and the laboratory information management systems. In 4% (3 hips), modular components were exchanged. To consider competing risks (death), we used competing risk models.

Results:

The competing risk analysis showed a successful outcome after DAIR of 82% at 4 years of follow-up; this rate was 89% at 4 years follow-up when excluding patients managed with gentamicin beads. The sensitivity analysis revealed that obesity (body mass index [BMI] of ≥30 kg/m²), use of gentamicin beads, and an erythrocyte sedimentation rate (ESR) of >40 mm/hr increased the risk of failure.

Conclusions:

DAIR using the direct anterior approach without the routine exchange of modular components offers a success rate that is comparable with other approaches for eradicating acute PJI following primary hip arthroplasty.

Level of Evidence:

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

Exchange of Modular Components Improves Success of Debridement, Antibiotics, and Implant Retention: An Observational Study of 575 Patients with Infection After Primary Total Hip Arthroplasty

Debridement, antibiotics, and implant retention (DAIR) is a surgical treatment for periprosthetic joint infection (PJI). DAIR is a desirable treatment option from an economic and patient perspective, if successful. The aim of this observational study was to compare the rates of success, defined as no additional reoperations due to PJI, between DAIR with exchange of modular components and DAIR without exchange in patients who had first-time PJI after primary total hip arthroplasty (THA).

METHODS

Patients with PJI at the site of a primary THA who were treated with DAIR in Sweden between January 1, 2009, and December 31, 2016, were identified in the Swedish Hip Arthroplasty Register. Supplementary questionnaires were sent to orthopaedic departments for additional variables of interest related to PJI. The primary end point was another reoperation due to PJI within 2 years after the first-time DAIR. DAIR with exchange was compared with DAIR without exchange using Kaplan-Meier survival analysis and Cox regression analysis.

RESULTS

A total of 575 patients treated with DAIR for a first-time PJI at the site of a primary THA were analyzed; 364 underwent component exchange and 211 did not. The exchange of components was associated with a lower rate of reoperations due to PJI after DAIR (28.0%) compared with non-exchange (44.1%). The Kaplan-Meier implant survival estimate for exchange was 71.4% (95% confidence interval [CI] = 66.9% to 76.3%) compared with 55.5% (95% CI = 49.1% to 62.7%) for non-exchange. With the analysis adjusted for confounders, DAIR with exchange was associated with a significantly decreased risk of another reoperation due to PJI compared with non-exchange (hazard ratio [HR] = 0.51 [95% CI = 0.38 to 0.68]).

CONCLUSIONS

In patients with a first-time PJI at the site of a primary THA, DAIR with exchange of modular components was superior to non-exchange DAIR. Surgeons should strive to exchange components when they perform DAIR, but there is a need to further identify how DAIR best should be practiced and which patients benefit from it.

LEVEL OF EVIDENCE

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

2020 Frank Stinchfield Award: Identifying who will fail following irrigation and debridement for prosthetic joint infection

AIMS

Failure of irrigation and debridement (I&D) for prosthetic joint infection (PJI) is influenced by numerous host, surgical, and pathogen-related factors. We aimed to develop and validate a practical, easy-to-use tool based on machine learning that may accurately predict outcome following I&D surgery taking into account the influence of numerous factors.

METHODS

This was an international, multicentre retrospective study of 1,174 revision total hip (THA) and knee arthroplasties (TKA) undergoing I&D for PJI between January 2005 and December 2017. PJI was defined using the Musculoskeletal Infection Society (MSIS) criteria. A total of 52 variables including demographics, comorbidities, and clinical and laboratory findings were evaluated using random forest machine learning analysis. The algorithm was then verified through cross-validation.

RESULTS

Of the 1,174 patients that were included in the study, 405 patients (34.5%) failed treatment. Using random forest analysis, an algorithm that provides the probability for failure for each specific patient was created. By order of importance, the ten most important variables associated with failure of I&D were serum CRP levels, positive blood cultures, indication for index arthroplasty other than osteoarthritis, not exchanging the modular components, use of immunosuppressive medication, late acute (haematogenous) infections, methicillin-resistant Staphylococcus aureus infection, overlying skin infection, polymicrobial infection, and older age. The algorithm had good discriminatory capability (area under the curve = 0.74). Cross-validation showed similar probabilities comparing predicted and observed failures indicating high accuracy of the model.

CONCLUSION

This is the first study in the orthopaedic literature to use machine learning as a tool for predicting outcomes following I&D surgery. The developed algorithm provides the medical profession with a tool that can be employed in clinical decision-making and improve patient care. Future studies should aid in further validating this tool on additional cohorts. Cite this article: Bone Joint J 2020;102-B(7 Supple B):11-19.