Chronic Periprosthetic Hip Joint Infection. A Retrospective, Observational Study on the Treatment Strategy and Prognosis in 130 Non-Selected Patients

Long-Term Outcome of Treating Periprosthetic Hip Joint Infection with Local Antibiotics Delivered Through Antibiotic-Impregnated Calcium Hydroxyapatite

Background/Objectives: This study explores the long-term clinical outcomes of antibiotic-impregnated calcium hydroxyapatite (CHA) as an antibiotic delivery system in treating periprosthetic joint infection (PJI) following total hip arthroplasty (THA). Methods: We conducted a retrospective analysis of 12 patients (13 hips) who were treated with antibiotic-impregnated CHA for PJI after THA and followed for more than 10 years at our institution between 1999 and 2011. The study group comprised six men (seven hips) and six women, with a mean age of 61.4 years. Results: The mean follow-up duration was 13.8 years. After irrigation and debridement with modular component exchange, seven hips in six patients underwent revision surgery; however, PJI relapsed in two hips of two patients with a history of diabetes. Two-stage revision surgery was performed on the two relapsed hips and six scheduled hips with antibiotic-impregnated CHA used to treat all cases of PJI. Infection control (100% rate) was achieved in all joints, and revision surgeries were completed. Two patients died 12 years after the initial procedure, and one died 14 years after the first procedure due to unrelated internal diseases; no infection recurrence was observed. No complications related to antibiotic-impregnated CHA were observed. Conclusions: Our results indicate that antibiotic-impregnated CHA is associated with high success rates in treating PJI after THA, even in cases with advanced disease, and yields satisfactory functional outcomes postoperatively.

Main Operating Room Versus Field Sterility in Hand Surgery: A Review of the Evidence

Introduction: Many of the guidelines that are generally accepted as main operating room best practices are not evidence based. They are based on the concept that if some sterility is good, more must be better. They are not derived from evidence-based sterility. Evidence-based sterility is the study of which of our various sterility practices increase or decrease our infection rates, as opposed to guidelines based on how many bacteria are in the operating room. Methods: This article adds the most important evidence we could find that is not included in the first paper on evidence-based sterility in hand surgery published in 2019. In this review, we also balance the evidence with common sense opinion. Results: The 21st century has seen a rapid rise in the number and reports of hand surgery procedures performed with field sterility outside the main operating room. There is now an abundance of good evidence to support that the rate of infection is not higher when many hand operations are performed with field sterility in minor procedure rooms. Conclusion: Moving hand surgery out of the main operating room to minor procedure rooms should be supported by healthcare providers. The higher cost, increased solid waste, and inconvenience of main operating room surgery are not justifiable for many procedures because it does not reduce the risk of postoperative infection.

Operating Room Airborne Microbial Load: Nonscrubbed Staff Apparel Matters

BACKGROUND

Infection is a leading cause of total joint arthroplasty failure. In previous studies, we found correlations between the level of contamination, concentrations of airborne particles, and the number of staff present. In this study, we focused on the apparel of nonscrubbed operating room (OR) staff to elucidate their contribution to the airborne microbial load.

METHODS

We compared hospital-laundered scrubs to disposable coveralls using 2 methods. (1) Participants entered an isolation chamber with a controlled environment and completed tasks for 1 hour wearing both the approved and alternative OR attire. Settle plates collected viable contaminants that were shed by the participants during testing. (2) Lab members conducted standardized maneuvers in a functional OR that simulated typical movements of the nurse, anesthesiologist, implant representative, and entering/exiting staff. An airborne particle counter and settle plates were positioned throughout the OR. After 1 hour, the staff changed apparel and repeated the test. Each session of both phases consisted of 2 tests by the same individuals on the same day.

RESULTS

There was approximately a 10-fold difference in the settlement rate of viable particles between groups when employing the isolation chamber. The settle rate for scrubs was 5,519 ± 1,381 colony forming units (CFUs)/m2/h, while the settle rate for coveralls was 505 ± 55 CFUs/m2/h (P = .008). During testing in the OR, 218.7 ± 35 CFUs/m2/h were captured for scrubs, compared with 50.5 ± 13 CFUs/m2/h for the coverall (P < .01). The concentration of airborne particles collected for scrubs was 4,952.1 ± 495 particles/m3 and 1,065 ± 53 particles/m3 for the coveralls (P < .01). This was a 77% and 79% reduction for both measures, respectively.

CONCLUSIONS

The open nature of standard scrubs allows contaminated particles to escape into the OR environment, whereas the one-piece design of the coveralls restricts pathways of escape. The results of this study may be helpful when developing hospital infection prevention policies.

Wearing a Surgical Vest With a Sterile Surgical Helmet System Decreases Contamination of the Surgical Field

BACKGROUND

Sterile surgical helmet systems are frequently utilized in total knee arthroplasty procedures to protect the surgeon while maintaining a comfortable working environment. However, common helmet systems pressurize the space between the surgical gown and the surgeon's skin. In gowns with a back seam, this may allow contaminated skin particles to escape into the surgical field. By measuring bacterial colony-forming units (CFUs), this study sought to determine if occlusion of the open back seam reduced the risk of potential contamination.

METHODS

First, qualitative analysis depicting airflow variations between gown configurations was performed using the Schlieren Spherical Mirror imaging system. Each gown configuration consisted of a sterile surgical helmet and one of 3 gown configurations: a standard gown with rear-tied closure, a standard gown with a surgical vest, and a zippered Toga-style gown. Next, a surgeon then performed simulated surgical activities for 60 minutes within a 1.4 m3 isolation chamber with work surfaces and controllable filtered air exchanges. During each procedure, contaminated particles were collected on sets of agar settle plates positioned directly behind the surgeon. Upon completion, the agar plates were incubated in a biolab, and the number of bacterial and fungal CFUs was counted. The experimental procedure was repeated 12 times for each gown configuration, with sterilization of the chamber between runs. Contamination rates were expressed as CFUs/m2/h.

RESULTS

The mean contamination rate measured with the standard gown was 331.7 ± 52.0 CFU/m2/h. After the addition of a surgical vest, this rate decreased by 45% to 182.2 ± 30.8 CFU/m2/h (P = .02). Similarly, with the Toga-style gown, contamination rates dropped by 49% to 170.5 ± 41.9 CFU/m2/h (P = .01).

CONCLUSIONS

When used in conjunction with surgical helmet systems, conventional surgical gowns do not prevent potential contamination of the surgical field. We recommend that staff within the surgical field cover the back seam of standard gowns with a vest or don a zippered Toga-style gown.

Diagnostic Performance of a Molecular Assay in Synovial Fluid Targeting Dominant Prosthetic Joint Infection Pathogens

Prosthetic joint infection (PJI) is one of the most serious complications of joint replacement surgery among orthopedic surgeries and occurs in 1 to 2% of primary surgeries. Additionally, the cause of PJIs is mostly bacteria from the Staphylococcus species, accounting for more than 98%, while fungi cause PJIs in only 1 to 2% of cases and can be difficult to manage. The current gold-standard microbiological method of culturing synovial fluid is time-consuming and produces false-negative and -positive results. This study aimed to identify a novel, accurate, and convenient molecular diagnostic method. The DreamDX primer-hydrolysis probe set was designed for the pan-bacterial and pan-fungal detection of DNA from pathogens that cause PJIs. The sensitivity and specificity of DreamDX primer-hydrolysis probes were 88.89% (95% CI, 56.50-99.43%) and 97.62% (95% CI, 87.68-99.88%), respectively, compared with the microbiological method of culturing synovial fluid, and receiver operating characteristic (ROC) area under the curve (AUC) was 0.9974 (*** p < 0.0001). It could be concluded that the DreamDX primer-hydrolysis probes have outstanding potential as a molecular diagnostic method for identifying the causative agents of PJIs, and that host inflammatory markers are useful as adjuvants in the diagnosis of PJIs.

New Frontiers in Wide-Awake Surgery

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. Explain the most important benefits of wide-awake surgery to patients. 2. Tumesce large parts of the body with minimal pain local anesthesia injection technique to eliminate the need for sedation for many operations. 3. Apply tourniquet-free surgery to upper and lower limb operations to avoid the sedation required to tolerate tourniquet pain. 4. Move many procedures out of the main operating room to minor procedure rooms with no increase in infection rates to decrease unnecessary cost and solid waste in surgery.

SUMMARY

Three disruptive innovations are changing the landscape of surgery: (1) minimally painful injection of large-volume, low-concentration tumescent local anesthesia eliminates the need for sedation for many procedures over the entire body; (2) epinephrine vasoconstriction in tumescent local anesthesia is a good alternative to the tourniquet and proximal nerve blocks in extremity surgery (sedation for tourniquet pain is no longer required for many procedures); and (3) evidence-based sterility and the elimination of sedation enable many larger procedures to move out of the main operating room into minor procedure rooms with no increase in infection rates. This continuing medical education article explores some of the new frontiers in which these changes affect surgery all over the body.

Short-term Success in Treatment of an Acute Hematogenous Periprosthetic Hip Joint Infection with Debridement, Antibiotics, and Implant Retention

Introduction

Periprosthetic joint infection (PJI) is an unfortunate but frequent complication following total hip arthroplasty, with an incidence of 1%. Debridement, antibiotics, and implant retention is a treatment option for acute hematogenous PJI, with success rates reported up to 70%. Here, we present a case demonstrating short-term success using this treatment approach in a 74-year-old medically infirm patient.

Case Report

The patient - a 74-year-old male with well-functioning bilateral total hip arthroplasties performed 14 years prior - presented to a rural emergency department with an acute onset of right groin pain and dizziness. The patient was found to have sepsis, a right hip joint effusion, and periarticular abscesses on assessment. Synovial fluid aspiration from the right hip grew methicillin-sensitive Staphylococcus aureus. The patient was transferred to an outside hospital for limited debridement of the right hip joint, followed by transfer to our tertiary hospital. On arrival, consideration was given to performing an exchange arthroplasty. However, given the patient's medical frailty, it was felt that the risks were prohibitive, as supported by the presence of ileus, severe electrolyte imbalance, anemia requiring transfusion, anasarca, and vancomycin-resistant Enterococcus faecium infection of a sacral wound. The patient underwent surgery utilizing an established protocol of aggressive debridement and cleaning of the hip space, exchange of the modular arthroplasty components, and placement of antibiotic calcium sulfate beads for local delivery. The patient was treated with parenteral antibiotics followed by chronic oral antimicrobial suppression for 10 months after the final surgery. During treatment, the patient's inflammatory markers have normalized. The patient is ambulatory without assistive devices but uses an ankle orthosis due to a post-operative foot drop that did not resolve. The patient has regained satisfactory mobility with an Oxford hip score of 27.

Conclusion

This case demonstrates short-term success in the treatment of acute hematogenous PJI in a medically infirm patient utilizing debridement, antibiotics, and implant retention and may serve to inform future patient counseling.

Reduction in Operating Room Airborne Particle Burden and Time-Dependent Contamination of Sterile Instrument Trays With the Use of a Novel Air Filtration System

Introduction

Postoperative infections represent a substantial burden to patients and healthcare systems. To improve patient care and reduce healthcare expenditures, interventions to reduce surgical infections must be employed. The crystalline C-band ultraviolet (UV-C) air filtration technology (Aerobiotix Inc., Miamisburg, OH, USA) has been designed to reduce airborne bioburden through high-quality filtration and germicidal irradiation. The purpose of this study was to assess the ability of a novel UV-C air filtration device to reduce airborne particle counts and contamination of surgical instrument trays in an operating room (OR) setting.

Materials and methods

Thirty sterile instrument trays were opened in a positive-air-flow OR. The trays were randomly assigned to one of two groups (UV-C or control, n=15 per group). In the UV-C group, the UV-C filtration device was used and in the control, it was not. All trays were opened with the use of a sterile technique and left exposed in the OR for four hours. Air was sampled by a particle counter to measure the numbers of 5µm and 10µm particles. Culture specimens were obtained from the trays to assess for bacterial contamination. Outcome data were collected at 30-minute intervals for the duration of the four-hour study period.

Results

Use of the UV-C device resulted in statistically significant reductions in the numbers of 5µm (average of 64.9% reduction when compared with the control, p<0.001) and 10µm (average of 65.7% reduction when compared with the control, p<0.001)-sized particles detectable in the OR. There was no significant difference in the overall rates of contamination (33.3% in the control group vs. 26.7% in the UV-C group, p=1.0) or the time to contamination (mean survival of 114 minutes in the control group vs. 105 minutes in the UV-C group, p=0.72) of surgical instrument trays with the use of the UV-C device.

Conclusions

The results demonstrate that the UV-C filtration device can successfully reduce airborne bioburden in standard ORs, suggesting that it may have the potential to reduce the risk for wound and hardware infections. Further clinical trials are necessary to better determine the effect of this air filtration system on postoperative infection rates.

Long Term Results of Two-Stage Revision for Chronic Periprosthetic Hip Infection: A Multicenter Study

BACKGROUND

Two-stage exchange arthroplasty remains the gold standard in the United States for treatment of chronic periprosthetic joint infection (PJI). Long-term reinfection rates and clinical outcomes with sufficient subject numbers remain limited. The purpose was to evaluate the long-term outcomes following two-stage exchange following hip arthroplasty.

METHODS

Retrospective review of 221 patients who underwent two-stage exchange hip arthroplasty for chronic PJI at three large tertiary referral institutions from 1990-2015. Outcomes including reinfection, mortality, and all-cause revision were calculated. Cumulative incidence of reinfection with death as competing factor was also calculated. Risk factors for reinfection were determined using Cox multivariate regression analysis.

RESULTS

Rate of infection eradication and all-cause revision was 88.24% and 22.6%, respectively. Overall mortality rate was 40.72%. Patients with minimum five-year follow-up (n = 129) had a success rate of 91.47% with mortality rate of 41.1%. Major risk factors for reinfection included polymicrobial infection (HR = 2.36, 95% CI: 1.08-5.14) and antibiotic resistant organism (HR = 2.36, 95% CI: 1.10-5.04).

CONCLUSION

This is the largest series with greater than 5-year follow-up evaluating outcomes of two-stage exchange hip arthroplasty. This technique resulted in a relatively high infection eradication, however, the mortality rate is alarmingly high. Antibiotic resistant organisms appear to be highest risk factor for failure.

Factors associated with infection recurrence after two-stage exchange for periprosthetic hip infection

PURPOSE

Two-stage exchange is the treatment of choice for periprosthetic joint infection (PJI). Factors and outcomes associated with infection recurrence for hip PJI are limited. The primary aim of this study was to determine factors associated with infection recurrence after two-stage exchange. Secondary aims were survival, mobility, and the EuroQol five-dimension scale (EQ-5D-5L) health state.

METHODS

We retrospectively investigated patients with two-stage exchange for hip PJI at our institution from 2006 to 2017. Follow-up was conducted for a minimum of four years after the reimplantation.

RESULTS

We included 135 patients with 139 hip PJIs. The mean age of the patients was 69.6 years (range 32-88). The infection recurrence rate was 14.4% (n = 20) after a mean follow-up of 8.0 years (range 4.0-13.1). Four factors for recurrence were identified at the time of the first stage: previous orthopaedic diagnoses (p < 0.001), type of explanted prosthesis (p = 0.004), cultured microorganisms (p = 0.033), and sinus tract (p = 0.035). A longer surgical reimplantation time (p = 0.015) was the only one factor found at the second stage. The estimated Kaplan-Meier survival for the total sample was 9.0 years (95% confidence interval 8.3-9.8), without significant difference for those with infection recurrence compared to recurrence-free patients (log-rank 0.931). At the time of follow-up, 89 patients were alive. For these patients, Parker mobility score (p = 0.102), EuroQol five-dimensional scale (p = 0.099), and EQ Visual Analogue Scale (EQ-VAS) (p = 0.027) were inferior in those with infection recurrence, but significance was found only for VAS.

CONCLUSION

In this study with mid- to long-term follow-up, five factors for infection recurrence were identified. Recurrence did not affect survival, but health-related quality of life was inferior compared to recurrence-free patients. The results suggest that the period of the first stage including previous orthopaedic diagnoses requires more consideration in the future.

Complications in the treatment of periprosthetic joint infection of the hip: when do they occur?

Prosthetic joint infection (PJI) is a devastating complication after total hip arthroplasty (THA). The common treatment in the USA is a two-stage exchange which can be associated with significant morbidity and mortality. The purpose of this study was to analyze complications in the treatment course of patients undergoing two-stage exchange for PJI THA and determine when they occur. Methods: We analyzed all patients that underwent two-stage exchange arthroplasty for treatment of PJI after THA from January 2005 to January 2018 at a single institution. Complications were categorized as medical or surgical and divided into interstage and post-reimplantation. Minimum follow-up was 1 year. Success was based on the MusculoSkeletal Infection Society (MSIS) definition. Results: 205 hips (203 patients) underwent first stage of planned two-stage exchange. The median age was 68 (interquartile range (IQR) 18). There were 97 males and 106 females. Overall, 73/205 (38 %) patients had at least one complication during treatment: 13.5 % (25/185) of patients experienced a medical complication and 28.1 % (52/185) a surgical complication; 2.4 % died within 1 year of surgery, and 4.9 % (15/203) had mortality at a median of 2.5 years (IQR 4.9); 27 % of patients had complications during the interstage period, most commonly being recurrence of infection requiring additional surgery (63 %); and 14 % of patients experienced a complication following reimplantation, most commonly persistence or recurrence of infection (59 %). While 92 % of patients that initiated treatment were ultimately reimplanted, only 69 % were infection free at 1 year and required no additional treatment. Conclusions: While two-stage exchanges for PJI in THA have been reported as successful, there are few reports of the complications during the process. In our series, significant numbers of patients experienced complications, often during the interstage period, highlighting the morbidity of this method of treatment.

Systematic review of risk prediction studies in bone and joint infection: are modifiable prognostic factors useful in predicting recurrence?

Background: Classification systems for orthopaedic infection include patient health status, but there is no consensus about which comorbidities affect prognosis. Modifiable factors including substance use, glycaemic control, malnutrition and obesity may predict post-operative recovery from infection. Aim: This systematic review aimed (1) to critically appraise clinical prediction models for individual prognosis following surgical treatment for orthopaedic infection where an implant is not retained; (2) to understand the usefulness of modifiable prognostic factors for predicting treatment success. Methods: EMBASE and MEDLINE databases were searched for clinical prediction and prognostic studies in adults with orthopaedic infections. Infection recurrence or re-infection after at least 6 months was the primary outcome. The estimated odds ratios for the primary outcome in participants with modifiable prognostic factors were extracted and the direction of the effect reported. Results: Thirty-five retrospective prognostic cohort studies of 92 693 patients were included, of which two reported clinical prediction models. No studies were at low risk of bias, and no externally validated prediction models were identified. Most focused on prosthetic joint infection. A positive association was reported between body mass index and infection recurrence in 19 of 22 studies, similarly in 8 of 14 studies reporting smoking history and 3 of 4 studies reporting alcohol intake. Glycaemic control and malnutrition were rarely considered. Conclusion: Modifiable aspects of patient health appear to predict outcomes after surgery for orthopaedic infection. There is a need to understand which factors may have a causal effect. Development and validation of clinical prediction models that include participant health status will facilitate treatment decisions for orthopaedic infections.

Complications in the treatment of prosthetic joint infection

AIMS

Two-stage exchange arthroplasty is the most common definitive treatment for prosthetic joint infection (PJI) in the USA. Complications that occur during treatment are often not considered. The purpose of this study was to analyze complications in patients undergoing two-stage exchange for infected total knee arthroplasty (TKA) and determine when they occur.

METHODS

We analyzed all patients that underwent two-stage exchange arthroplasty for treatment of PJI of the knee from January 2010 to December 2018 at a single institution. We categorized complications as medical versus surgical. The intervals for complications were divided into: interstage; early post-reimplantation (three months); and late post-reimplantation (three months to minimum one year). Minimum follow-up was one year. In total, 134 patients underwent a first stage of a two-stage exchange. There were 69 males and 65 females with an mean age at first stage surgery of 67 years (37 to 89). Success was based on the new Musculoskeletal Infection Society (MSIS) definition of success reporting.

RESULTS

Overall, 70 (52%) patients experienced a complication during the planned two-stage treatment, 36 patients (27%) experienced a medical complication and 47 (41%) patients experienced a surgical complication. There was an 18% mortality rate (24/134) at a mean of 3.7 years (0.09 to 8.3). During the inter-stage period, 28% (37/134) of patients experienced a total of 50 complications at a median of 47 days (interquartile range (IQR) 18 to 139). Of these 50 complications, 22 were medical and 28 required surgery. During this inter-stage period, four patients died (3%) and an additional five patients (4%) failed to progress to the second stage. While 93% of patients (125/134) were reimplanted, only 56% (77/134) of the patients were successfully treated without antibiotic suppression (36%, 28/77) or with antibiotic suppression (19%, 15/77) at one year.

CONCLUSION

Reported rates of success of two stage exchanges for PJI have not traditionally considered complications in the definition of success. In our series, significant numbers of patients experienced complications, more often after reimplantation, highlighting the morbidity of this method of treatment. Cite this article: Bone Joint J 2020;102-B(6 Supple A):145-150.

Development and Validation of an Evidence-Based Algorithm for Diagnosing Periprosthetic Joint Infection

BACKGROUND

The guidelines for diagnosis of periprosthetic joint infection (PJI) introduced by the American Academy of Orthopaedic Surgeons served the orthopedic community well. However, they have never been validated and do not account for newer diagnostic modalities. Our aim was to update current guidelines and develop an evidence-based and validated diagnostic algorithm.

METHODS

This multi-institutional study examined total joint arthroplasty patients from 3 institutions. Patients fulfilling major criteria for infection as defined by Musculoskeletal Infection Society were considered infected (n = 684). Patients undergoing aseptic revision for a noninfective indication and did not show evidence of PJI or undergo reoperation within 2 years served as a noninfected control group (n = 820). The algorithm was validated on a separate cohort of 422 cases.

RESULTS

The first step in evaluating PJI should include a physical examination, followed by serum C-reactive protein, erythrocyte sedimentation rate, and D-dimer. If at least one of these tests are elevated, or if high clinical suspicion exists, joint aspiration should be performed, sending the fluid for a white blood cell count, leukocyte esterase, polymorphonuclear percentage, and culture. Alpha defensin did not show added benefit as a routine diagnostic test. In inconclusive cases, intraoperative findings including gross purulence, histology, and next-generation sequencing or a single positive culture can aid in making the diagnosis. The proposed algorithm demonstrated a high sensitivity (96.9%) and specificity (99.5%).

CONCLUSION

This validated, evidence-based algorithm for diagnosing PJI should guide clinicians in the workup of patients undergoing revision arthroplasty and improve clinical practice. It also has the potential to reduce cost.

Influence of a visible-light continuous environmental disinfection system on microbial contamination and surgical site infections in an orthopedic operating room

BACKGROUND

A growing body of research has demonstrated that manual cleaning and disinfection of the operating room (OR) is suboptimal. Residual environmental contamination may pose an infection risk to the surgical wound. This study evaluates the impact of a visible-light continuous environmental disinfection (CED) system on microbial surface contamination and surgical site infections (SSI) in an OR.

METHODS

Samples from 25 surfaces within 2 contiguous ORs sharing an air supply were obtained after manual cleaning on multiple days before and after a visible-light CED system installation in 1 of the ORs. Samples were incubated and enumerated as total colony-forming units. SSIs in both ORs, and a distant OR, were tracked for 1 year prior to and 1 year after the visible-light CED system installation.

RESULTS

There was an 81% (P = .017) and 49% (P = .015) reduction in total colony-forming units after the visible-light CED system installation in the OR in which the system was installed, and in the contiguous OR, respectively. In the OR with the visible-light CED system, SSIs decreased from 1.4% in the year prior to installation to 0.4% following installation (P = .029).

CONCLUSIONS

A visible-light CED system, used in conjunction with manual cleaning, resulted in significant reductions in both microbial surface contamination and SSIs in the OR.

Similar Risk of Re-Revision in Patients after One- or Two-Stage Surgical Revision of Infected Total Hip Arthroplasty: An Analysis of Revisions in the Swedish Hip Arthroplasty Register 1979⁻2015

Late chronic infection is a devastating complication after total hip arthroplasty (THA) and is often treated with surgery. The one-stage surgical procedure is believed to be the more advantageous from a patient and cost perspective, but there is no consensus on whether the one- or two-stage procedure is the better option. We analysed the risk for re-revision in infected primary THAs repaired with either the one- or two-stage method. Data was obtained from the Swedish Hip Arthroplasty Register and the study groups were patients who had undergone a one-stage (n = 404) or two-stage (n = 1250) revision due to infection. Risk of re-revision was analysed using Kaplan–Meier analysis with log-rank test and Cox regression analysis. The cumulative survival rate was similar in the two groups at 15 years after surgery (p = 0.1). Adjusting for covariates, the risk for re-revision due to all causes did not differ between patients who were operated on with the one- or two-stage procedure (Hazard Ratio (HR) = 0.9, 95% Confidence Interval (C.I.) = 0.7–1.2, p = 0.5). The risk for re-revision due to infection (HR = 0.7, 95% C.I. = 0.4–1.1, p = 0.2) and aseptic loosening (HR = 1.2, 95% C.I. = 0.8–1.8, p = 0.5) was similar. This study could not determine whether the one-stage method was inferior in cases when the performing surgeons chose to use the one-stage method.

High cure rate of periprosthetic hip joint infection with multidisciplinary team approach using standardized two-stage exchange

Background

Two-stage exchange arthroplasty is still the preferred treatment choice for chronic PJI. However, the results remain unpredictable. We analyzed the treatment success of patients with an infected hip prosthesis, who were treated according to a standardized algorithm with a multidisciplinary team approach and evaluated with a strict definition of failure.

Methods

In this single-center prospective cohort study, all hip PJI episodes from March 2013 to May 2015 were included. Treatment failure was assessed according to the Delphi-based consensus definition. The Kaplan-Meier survival method was used to estimate the probability of infection-free survival. Patients were dichotomized into two groups depending on the number of previous septic revisions, duration of prosthesis-free interval, positive culture with difficult-to-treat microorganisms, microbiology at explantation, and microbiology at reimplantation.

Results

Eighty-four patients with hip PJI were the subject of this study. The most common isolated microorganisms were coagulase-negative staphylococci (CNS) followed by Staphylococcus aureus and Propionibacterium. Almost half of the study cohort (46%) had at least one previous septic revision before admission. The Kaplan-Meier estimated infection-free survival after 3 years was 89.3% (95% CI, 80% to 94%) with 30 patients at risk. The mean follow-up was 33.1 months (range, 24–48 months) with successful treatment of PJI. There were no statistical differences in infect eradication rate among the dichotomized groups.

Conclusions

High infect eradication rates were achieved in a challenging cohort using a standardized two-stage exchange supported by a multidisciplinary approach.

Patient-reported quality of life and hip function after 2-stage revision of chronic periprosthetic hip joint infection: a cross-sectional study

INTRODUCTION

Very limited information is available regarding patient-reported health-related quality of life (HRQoL) and hip function following treatment for chronic periprosthetic hip joint infection (PJI). Patient-reported outcome measures provide essential information to clinicians of the impact a treatment have on patient's lives. The purpose of this study was to examine patient reported HRQoL and hip function after a completed re-implantation in a 2-stage revision.

METHOD

82 patients were identified retrospectively in the National Patient Register. 57 patients were alive and asked to complete the questionnaires EuroQol-5D (EQ-5D) and Oxford Hip Score (OHS) in November 2014. Results were compared to normative population data for EQ-5Dindex. Patients re-infected after a completed 2-stage revision were compared with not re-infected.

RESULTS

45 patients completed the questionnaires. Mean time since re-implantation was 8.2 years (95% CI [confidence interval], 7.7-0.87). The EQ-5D index mean for the 2-stage group was 0.71 (0.64; 0.77) whereas the general population mean is 0.85 (0.84-0.85), p = 0.0004. The 2-stage revision patients scored significantly lower on every EQ-5D dimension. The re-infected group mean EQ-5D index score was significantly lower compared to the not re-infected group, p = 0.003. The EQ-VAS mean score was 58.2 (57.3-68.3) and the mean OHS for the group was 29.2 (25.4-33.0).

CONCLUSIONS

Patients who undergo 2-stage revision after a PJI have lower scores on HRQoL than the general population. Patients who are re-infected following revision have a lower HRQoL score than patients not re-infected. Future research should focus on optimising patient-reported outcomes after treatment for PJI.

Cementless One-Stage Revision in Chronic Periprosthetic Hip Joint Infection. Ninety-One Percent Infection Free Survival in 56 Patients at Minimum 2-Year Follow-Up

BACKGROUND

Cementless 1-stage revision in chronic periprosthetic hip joint infections is limited evaluated. The purpose of this study was to evaluate a specific treatment protocol in this patient group.

METHODS

The study was performed as a multicenter, proof-of-concept, observational study with prospective data collection. Patients were treated with a cementless 1-stage revision according to the CORIHA protocol between 2009 and 2014. Fifty-six patients, McPherson type III-A/B-1/2, were enrolled with a mean follow-up time from the CORIHA procedure of 4 years (minimum of 2 years). The primary outcome was re-revision performed due to infection and was evaluated by competing risk analysis, with death and aseptic revision as competing events. All-cause mortality was evaluated by Kaplan-Meier survival analysis. Oxford Hip Score (OHS) was used as disease-specific patient-reported outcome measure.

RESULTS

The cumulative incidence of re-revision due to infection was 8.9% (confidence interval [CI] 3.2%-18.1%). The 1-year and 5-year survival incidence was 96% (CI 86%-99%) and 89% (CI 75%-95%). OHS at baseline was 19.9 (CI 17.3-22.6) and at 24-month follow-up 35.1 (CI 31.7-38.5). The mean change in OHS from baseline to 24-month follow-up was 11.8 points (CI 7.3; 16.3). Three patients had aseptic revision performed: two suffered periprosthetic fractures and one had stem subsidence. Failure analysis of the 5 reinfections did not detect a clear pattern as to the cause of failure.

CONCLUSION

We found that cementless 1-stage revision in chronic periprosthetic hip joint infections has low reinfection rates in selected patients and may be applicable as a first-line treatment.

Revision Total Knee Arthroplasty for Periprosthetic Joint Infection Is Associated With Increased Postoperative Morbidity and Mortality Relative to Noninfectious Revisions

BACKGROUND

Periprosthetic joint infection (PJI) after primary total knee arthroplasty (TKA) is a devastating complication. The short-term morbidity profile of revision TKA performed for PJI relative to non-PJI revisions is poorly characterized. The purpose of this study is to determine 30-day postoperative outcomes after revision TKA for PJI, relative to primary TKA and aseptic revision TKA.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program from 2005 to 2015 was queried for primary and revision TKA cases. Revision TKA cases were categorized into PJI and non-PJI cohorts. Differences in 30-day outcomes including postoperative complications, readmissions, operative time, and length of stay were compared using bivariate and multivariate analyses.

RESULTS

In total, 175,761 TKAs were included in this study, with 162,981 (92.7%) primary TKAs and 12,780 (7.3%) revision TKAs, of which 2196 (17.2%) revisions were performed for PJI. When compared to aseptic revision TKA, multivariate analysis demonstrated that PJI revisions had a significantly higher risk of major early postoperative complications including death (adjusted odds ratio [OR] 3.25) and sepsis (OR 8.73). In addition, nonhome discharge (OR 1.75), readmissions (OR 1.67), and length of stay (+2.1 days) were all greater relative to non-PJI revisions.

CONCLUSION

Utilizing a large, prospectively collected, national database, we found that revision TKA for PJI has a greater risk of short-term morbidity and mortality and requires a higher utilization of healthcare resources. These results have implications for patient counseling and alternative payment models that may eventually include revision TKA.

Environment of care: Is it time to reassess microbial contamination of the operating room air as a risk factor for surgical site infection in total joint arthroplasty?

In the modern operating room (OR), traditional surgical mask, frequent air exchanges, and architectural barriers are viewed as effective in reducing airborne microbial populations. Intraoperative sampling of airborne particulates is rarely performed in the OR because of technical difficulties associated with sampling methodologies and a common belief that airborne contamination is infrequently associated with surgical site infections (SSIs). Recent studies suggest that viable airborne particulates are readily disseminated throughout the OR, placing patients at risk for postoperative SSI. In 2017, virtually all surgical disciplines are engaged in the implantation of selective biomedical devices, and these implants have been documented to be at high risk for intraoperative contamination. Approximately 1.2 million arthroplasties are performed annually in the United States, and that number is expected to increase to 3.8 million by the year 2030. The incidence of periprosthetic joint infection is perceived to be low (<2.5%); however, the personal and fiscal morbidity is significant. Although the pharmaceutic and computer industries enforce stringent air quality standards on their manufacturing processes, there is currently no U.S. standard for acceptable air quality within the OR environment. This review documents the contribution of air contamination to the etiology of periprosthetic joint infection, and evidence for selective innovative strategies to reduce the risk of intraoperative microbial aerosols.