Multiplex PCR test as an intra-operative diagnostic tool for periprosthetic joint infection in presumed aseptic revision hip and knee arthroplasty: a 1-year follow-up study of 200 cases.

Automated custom-made multiplex PCR techniques (mPCR) have become commercially available and are designed for intra-operative screening of concurrent periprosthetic joint infections (PJIs). The purpose of this study was to evaluate the value of a positive mPCR test in presumed aseptic revision total hip (THA) and knee (TKA) arthroplasties after a 1-year follow-up. In an earlier study, such an automated mPCR technique (Unyvero ITI G2; Curetis, Holzgerlingen, Germany) was tested on intra-operatively obtained synovial fluid in 200 patients with a presumed aseptic TKA or THA revision. At the time of revision, no therapeutic consequences were attached to a positive test result since treating personnel were blinded for the test results. We retrospectively reviewed the outcome of cases with respect to the occurrence of PJIs using the European Bone and Joint Infection Society (EBJIS) criteria during a 1-year follow-up postoperatively. A total of 10 out of 200 patients had a positive mPCR test result at the time of revision. Of these 10 cases, none encountered outcome parameters fulfilling the criteria to diagnose PJIs in the first year after surgery, and one required re-revision surgery for reasons other than infection. Of the other 190 negative mPCR cases, none developed a PJI. A positive mPCR test at the time of presumed aseptic revision surgery did not correspond with intra-operatively obtained tissue cultures, and none of the encountered positive mPCR tests had developed a PJI at the 1-year follow-up. We recommend careful evaluation and monitoring of modern diagnostic tests before widespread use.

Incisional Wound Irrigation for the Prevention of Surgical Site Infection: A Systematic Review and Network Meta-Analysis.

Importance: Surgical site infections (SSIs) are common postoperative complications and associated with significant morbidity, mortality, and costs. Prophylactic intraoperative incisional wound irrigation is used to reduce the risk of SSIs, and there is great variation in the type of irrigation solutions and their use. Objective: To compare the outcomes of different types of incisional prophylactic intraoperative incisional wound irrigation for the prevention of SSIs in all types of surgery. Data Sources: PubMed, Embase, CENTRAL, and CINAHL databases were searched up to June 12, 2023. Study Selection: Included in this study were randomized clinical trials (RCTs) comparing incisional prophylactic intraoperative incisional wound irrigation with no irrigation or comparing irrigation using different types of solutions, with SSI as a reported outcome. Studies investigating intracavity lavage were excluded. Data Extraction and Synthesis: This systematic review and network meta-analysis is reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement. Two reviewers independently extracted the data and assessed the risk of bias within individual RCTs using the Cochrane Risk of Bias 2 tool and the certainty of evidence using the Grading of Recommendations, Assessment, Development, and Evaluation framework. A frequentist network meta-analysis was conducted, and relative risks (RRs) with corresponding 95% CIs were reported. Main Outcome and Measure: The primary study outcome was SSI. Results: A total of 1587 articles were identified, of which 41 RCTs were included in the systematic review, with 17 188 patients reporting 1328 SSIs, resulting in an overall incidence of 7.7%. Compared with no irrigation, antiseptic solutions (RR, 0.60; 95% CI, 0.44-0.81; high level of certainty) and antibiotic solutions (RR, 0.46; 95% CI, 0.29-0.73; low level of certainty) were associated with a beneficial reduction in SSIs. Saline irrigation showed no statistically significant difference compared with no irrigation (RR, 0.83; 95% CI, 0.63-1.09; moderate level of certainty). Conclusions and Relevance: This systematic review and network meta-analysis found high-certainty evidence that prophylactic intraoperative incisional wound irrigation with antiseptic solutions was associated with a reduction in SSIs. It is suggested that the use of antibiotic wound irrigation be avoided due to the inferior certainty of evidence for its outcome and global antimicrobial resistance concerns.

No difference in bacterial contamination of hip capsule sutures and control sutures in hip arthroplasty surgery.

BACKGROUND: Perioperative preventive measures are important to further reduce the rate of periprosthetic joint infections (PJI) in patients undergoing total hip arthroplasty (THA). During THA surgery, joint capsule sutures are commonly placed to optimize exposure and reinsertion of the capsule. Bacterial contamination of these sutures during the procedure poses a potential risk for postoperative infection. In this exploratory study, we assessed the contamination rate of capsule sutures compared to the contamination of the remains of exchanged control sutures at the time of closure. METHODS: In 100 consecutive patients undergoing primary THA capsule sutures were exchanged by sterile sutures at the time of capsule closure. Both the original sutures and the remainder of the newly placed (control) sutures were retrieved, collected and cultured for ten days. Types of bacterial growth and contamination rates of both sutures were assessed. RESULTS: Sutures from 98 patients were successfully collected and analyzed. Bacterial growth was observed in 7/98 (7.1%) of the capsule sutures versus 6/98 (6.1%) of the control sutures, with a difference of 1% [CI -6-8]. There was no clear pattern in differences in subtypes of bacteria between groups. CONCLUSIONS: This study showed that around 7% of capsule sutures used in primary THA were contaminated with bacteria and as such exchange by new sutures at the time of capsule closure could be an appealing PJI preventive measure. However, since similar contamination rates were encountered with mainly non-virulent bacteria for both suture groups, the PJI preventive effect of this measure appears to be minimal.

Incisional negative pressure wound therapy for the prevention of surgical site infection: an up-to-date meta-analysis and trial sequential analysis.

Background: The evidence on prophylactic use of negative pressure wound therapy on primary closed incisional wounds (iNPWT) for the prevention of surgical site infections (SSI) is confusing and ambiguous. Implementation in daily practice is impaired by inconsistent recommendations in current international guidelines and published meta-analyses. More recently, multiple new randomised controlled trials (RCTs) have been published. We aimed to provide an overview of all meta-analyses and their characteristics; to conduct a new and up-to-date systematic review and meta-analysis and Grading of Recommendations Assessment, Development and Evaluation (GRADE) assessment; and to explore the additive value of new RCTs with a trial sequential analysis (TSA). Methods: PubMed, Embase and Cochrane CENTRAL databases were searched from database inception to October 24, 2022. We identified existing meta-analyses covering all surgical specialties and RCTs studying the effect of iNPWT compared with standard dressings in all types of surgery on the incidence of SSI, wound dehiscence, reoperation, seroma, hematoma, mortality, readmission rate, skin blistering, skin necrosis, pain, and adverse effects of the intervention. We calculated relative risks (RR) with corresponding 95% confidence intervals (CI) using a Mantel-Haenszel random-effects model. We assessed publication bias with a comparison-adjusted funnel plot. TSA was used to assess the risk of random error. The certainty of evidence was evaluated using the Cochrane Risk of Bias-2 (RoB2) tool and GRADE approach. This study is registered with PROSPERO, CRD42022312995. Findings: We identified eight previously published general meta-analyses investigating iNPWT and compared their results to present meta-analysis. For the updated systematic review, 57 RCTs with 13,744 patients were included in the quantitative analysis for SSI, yielding a RR of 0.67 (95% CI: 0.59-0.76, I2 = 21%) for iNPWT compared with standard dressing. Certainty of evidence was high. Compared with previous meta-analyses, the RR stabilised, and the confidence interval narrowed. In the TSA, the cumulative Z-curve crossed the trial sequential monitoring boundary for benefit, confirming the robustness of the summary effect estimate from the meta-analysis. Interpretation: In this up-to-date meta-analysis, GRADE assessment shows high-certainty evidence that iNPWT is effective in reducing SSI, and uncertainty is less than in previous meta-analyses. TSA indicated that further trials are unlikely to change the effect estimate for the outcome SSI; therefore, if future research is to be conducted on iNPWT, it is crucial to consider what the findings will contribute to the existing robust evidence. Funding: Dutch Association for Quality Funds Medical Specialists.

Debridement, Antibiotics and Implant Retention: A Systematic Review of Strategies for Treatment of Early Infections after Revision Total Knee Arthroplasty.

GOAL: The purpose of this review is to provide a systematic and comprehensive overview of the available literature on the treatment of an early prosthetic joint infection (PJI) after revision total knee arthroplasty (TKA) and provide treatment guidelines. METHODS: This systematic review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. The search was conducted using the electronic databases of PubMed, Trip, Cochrane, Embase, LILACS and SciElo. After the inclusion of the relevant articles, we extracted the data and results to compose a treatment algorithm for early and acute PJI after revision TKA. RESULTS: After applying the in- and exclusion criteria, seven articles were included in this systematic review focusing on debridement, antibiotics and implant retention (DAIR) for PJI following revision TKA, of which one was prospective and six were retrospective. All studies were qualified as level IV evidence. CONCLUSIONS: The current literature suggests that DAIR is a valid treatment option for early infections after revision TKA with success rates of 50-70%. Repeat DAIR shows success rates of around 50%. Further research should be aimed at predicting successful (repeat/two-stage) DAIRs in larger study populations, antibiotic regimes and the cost effectiveness of a second DAIR after revision TKA.

Higher 1-year risk of implant removal for culture-positive than for culture-negative DAIR patients following 359 primary hip or knee arthroplasties.

Background and purpose: To date, the value of culture results after debridement, antibiotics, and implant retention (DAIR) for early (suspected) prosthetic joint infection (PJI) as risk indicators in terms of prosthesis retention is not clear. At the 1-year follow-up, the relative risk of prosthesis removal was determined for culture-positive and culture-negative DAIR patients after primary total hip or knee arthroplasty. The secondary aim of this work was to explore differences in patient characteristics, infection characteristics, and outcomes between these two groups. Methods: A retrospective regional registry study was performed in a group of 359 patients (positive cultures: n = 299 ; negative cultures: n = 60 ) undergoing DAIR for high suspicion of early PJI in the period from 2014 to 2019. Differences in patient characteristics, the number of deceased patients, and the number of subsequent DAIR treatments between the culture-positive and culture-negative DAIR groups were analysed using independent t  tests, Mann-Whitney U  tests, Pearson's chi-square tests, and Fisher's exact tests. Results: The overall implant survival rate following DAIR was 89 %. The relative risk of prosthesis removal was 7.4 times higher (95 % confidence interval (CI) 1.0-53.1) in the culture-positive DAIR group (37 of 299, 12.4 %) compared with the culture-negative DAIR group (1 of 60, 1.7 %). The culture-positive group had a higher body mass index ( p = 0.034 ), a rate of wound leakage of > 10  d ( p = 0.016 ), and more subsequent DAIR treatments ( p = 0.006 ). Interpretation: As implant survival results after DAIR are favourable, the threshold to perform a DAIR procedure for early (suspected) PJI should be low in order to retain the prosthesis. A DAIR procedure in the case of negative cultures does not seem to have unfavourable results in terms of prosthesis retention.

Patient-reported outcome measures, complication rates, and re-revision rates are not associated with the indication for revision total hip arthroplasty : a prospective evaluation of 647 consecutive patients.

AIMS: The aim of this study was to explore the relationship between reason for revision total hip arthroplasty (rTHA) and outcomes in terms of patient-reported outcome measures (PROMs). METHODS: We reviewed a prospective cohort of 647 patients undergoing full or partial rTHA at a single high-volume centre with a minimum of two years' follow-up. The reasons for revision were classified as: infection; aseptic loosening; dislocation; structural failure; and painful THA for other reasons. PROMs (modified Oxford Hip Score (mOHS), EuroQol five-dimension three-level health questionnaire (EQ-5D-3L) score, and visual analogue scales for pain during rest and activity), complication rates, and failure rates were compared among the groups. RESULTS: The indication for revision influenced PROMs improvement over time. This finding mainly reflected preoperative differences between the groups, but diminished between the first and second postoperative years. Preoperatively, patients revised due to infection and aseptic loosening had a lower mOHS than patients with other indications for revision. Pain scores at baseline were highest in patients being revised for dislocation. Infection and aseptic loosening groups showed marked changes over time in both mOHS and EQ-5D-3L. Overall complications and re-revision rates were 35.4% and 9.7% respectively, with no differences between the groups (p = 0.351 and p = 0.470, respectively). CONCLUSION: Good outcomes were generally obtained regardless of the reason for revision, with patients having the poorest preoperative scores exhibiting the greatest improvement in PROMs. Furthermore, overall complication and reoperation rates were in line with previous reports and did not differ between different indications for rTHA. Cite this article: Bone Joint J 2022;104-B(7):859-866.

Debridement, antibiotics, and implant retention after revision arthroplasty : antibiotic mismatch, timing, and repeated DAIR associated with poor outcome.

AIMS: Debridement, antibiotics, and implant retention (DAIR) is a widely accepted form of surgical treatment for patients with an early periprosthetic joint infection (PJI) after primary arthroplasty. The outcome of DAIR after revision arthroplasty, however, has not been reported. The aim of this study was to report the success rate of DAIR after revision arthroplasty with a follow-up of two years. METHODS: This retrospective study, conducted at the Sint Maartenskliniek, Nijmegen, the Netherlands, included 88 patients who underwent DAIR within 90 days of revision total hip or total knee arthroplasty between 2012 and 2019. Details of the surgical procedures and PJI were collected. Univariate analysis and a subgroup analysis of the culture-positive group were performed. Kaplan-Meier survivorship curves were constructed. RESULTS: The overall success rate of DAIR, with respect to the retention of components and the cure of infection, was 68% after two years. DAIR performed with an interval of > 30 days after the index revision procedure (odds ratio (OR) 0.24 (95% confidence interval (CI) 0.08 to 0.72); p = 0.008), a repeated DAIR within 90 days (OR 0.37 (95% CI 0.14 to 0.97); p = 0.040), and the use of an immunosuppressive agent (OR 0.13 (95% CI 0.02 to 0.67); p = 0.012) were associated with a significantly reduced success rate. In the culture-positive group, a mismatch between the antibiotic treatment and the susceptibility of the organism was associated with a significantly lower success rate (OR 0.13 (95% CI 0.03 to 0.62); p = 0.007). CONCLUSION: DAIR is an acceptable form of surgical treatment for patients with a suspected early PJI after revision arthroplasty of the hip or knee. DAIRs performed after a prolonged interval, multiple DAIRs, and antibiotic mismatches were significantly associated with an increased risk of failure. Optimization of the host immune response and the prevention of antibiotic mismatch are modifiable factors that may improve the outcome. The high rate of mismatches was an important finding, underlining the need for a review of the local microbiological data, which might improve the outcome. Cite this article: Bone Joint J 2022;104-B(4):464-471.

Mismatch in Capture of Periprosthetic Joint Infections Between the Dutch Arthroplasty Register (LROI) and a Detailed Regional Periprosthetic Joint Infection Registry.

BACKGROUND: National arthroplasty registries are important sources for periprosthetic joint infection (PJI) data and report an average incidence ranging from 0.5% to 2.0%. However, studies have shown that PJI incidence in national arthroplasty registries may be underestimated. Therefore, the incidence of PJI in the Dutch Arthroplasty Register (LROI) was evaluated. METHODS: We matched revisions due to infection within 90 days of index procedure in the LROI database (prospectively registered in 2014-2018) with acute PJI cases registered in a Regional Infection Cohort (RIC) and vice versa. The RIC comprised of 1 university hospital, 3 large orthopedic teaching hospitals and 4 general district hospitals, representing 11.3% of all Dutch arthroplasty procedures with a similar case mix. RESULTS: From the 352 acute PJIs in the RIC, 166 (47%) were registered in the LROI. Of the 186 confirmed PJI cases not registered in the LROI, 51% (n = 95) were a unregistered Debridement, Antibiotics, and Implant Retention procedure without component exchange. The remaining missing PJI cases (n = 91, 49%) were of administrative origin. The acute PJI incidence in the RIC was 1%, compared to a 0.6% incidence of revision <90 days due to infection from LROI data. CONCLUSION: Besides unregistered Debridement, Antibiotics, and Implant Retention procedures without component exchange, administrative errors are an important source of missing PJI data for the LROI, leading to underestimation of PJI incidence in the Netherlands. A national arthroplasty complication registry, linked to the LROI, might decrease the number of missing PJI cases. Although our study concerns Dutch data, it supports the scarce literature on PJI incidence obtained from national arthroplasty registries, which also reports an underestimation.

The concordance between preoperative synovial fluid culture and intraoperative tissue cultures in periprosthetic joint infection: a systematic review.

Background: this systematic review aims to evaluate the concordance between preoperative synovial fluid culture and intraoperative tissue cultures in patients with periprosthetic joint infection (PJI) undergoing total hip (THA) or knee arthroplasty (TKA) revision surgery. Methods: this review was conducted in accordance with the preferred reporting items for a systematic review and meta-analysis of diagnostic test accuracy studies (PRISMA-DTA) statement. Cochrane, Embase, PubMed, and Web of Science databases were searched to identify studies involving patients who had THA or TKA revision surgery for PJI and for whom preoperative synovial fluid culture and intraoperative tissue cultures were performed. Studies were only included if the diagnosis of PJI was based on the EBJIS (the European Bone and Joint Infection Society) or MSIS (Musculoskeletal Infection Society) criteria. Risk of bias was assessed using an amended version of Joanna Briggs Institute's (JBI) critical appraisal checklist for case series. Results: seven studies were included in this review comprising 1677 patients. All studies had a retrospective study design and five studies explored patients undergoing revision surgery of THA or TKA. Concordance rates varied between 52 % and 79 %, but different authors defined and calculated concordance differently. Six studies were judged as having an unclear to high risk of bias and one study as having a low risk of bias. Conclusions: the included studies showed a wide range of concordance rates between preoperative synovial fluid culture and intraoperative tissue cultures and the majority of studies had a high risk of bias. Higher-quality studies are warranted to obtain a more accurate estimate of this concordance rate. We recommend continuing the use of a system such as the EBJIS definition or MSIS criteria when diagnosing PJI.

Ruling out underlying infection in 200 presumed aseptic knee and hip revision arthroplasties using a multiplex PCR system.

Ruling out an infection in one-stage knee and hip revisions for presumed aseptic failure by conventional tissue cultures takes up to 14 days. Multiplex polymerase chain reaction (mPCR) is a quick test (4-5 h) for detecting pathogens. The purpose of this study was to evaluate the diagnostic accuracy of an automated mPCR of synovial fluid obtained intraoperatively in unsuspected knee and hip revisions. A prospective study was conducted with 200 patients undergoing a one-stage knee or hip revision. Synovial fluid was analyzed with the mPCR Unyvero implant and tissue infection G2 cartridge (U-ITI G2) system and compared to intraoperative tissue cultures. The primary outcome measure was the diagnostic accuracy, including sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV), of the mPCR U-ITI G2 system compared to conventional cultures. In the knee revision group, there were no patients with a positive mPCR in combination with positive cultures. This resulted in a non-calculable sensitivity and PPV. The specificity and NPV in the knee revision group of the mPCR compared to tissue cultures was 96.8% and 96.8%, respectively. In the hip revision group, the sensitivity, specificity, PPV, and NPV of the mPCR compared to tissue cultures was 36.4%, 96.6%, 57.1%, and 92.5%, respectively. Sixteen mismatches occurred between the mPCR and tissue cultures. The mPCR U-ITI G2 system is a quick and reliable synovium fluid test for ruling out infection in presumed aseptic knee and hip revisions with a high NPV compared with tissue cultures, although some mismatches were observed. Periprosthetic tissue cultures are still advised as back-up for false negative and positive mPCR test results.

Reinfection and re-revision rates of 113 two-stage revisions in infected TKA.

Introduction: Two-stage revision is the most frequently performed revision procedure of a (suspected) periprosthetic joint infection (PJI) after total knee arthroplasty (TKA). The reported results of this treatment show large variability between studies, ranging between 0 - 40 percent failure. The purposes of this study were to determine long term (1) reinfection rate, (2) re-revision rates for any reason, and (3) the reinfection rate of patients with positive cultures at reimplantation. Methods: We prospectively followed and retrospectively reviewed 113 consecutive two-stage revision TKAs, performed between 2003 and 2013 in our clinic with a minimum follow-up of 2 years. Diagnosis of PJI was based on the major Musculoskeletal Infection Society criteria for PJI. Results: After a mean follow-up of 94 months (range 24-172 months), infection recurred in 23 cases (23%). Of these, nine cases (9%) were defined as relapse (same micro-organism as index revision) and in 14 cases another causative was found (14%). In 11 patients debridement, antibiotics and retention of the prosthesis successfully eradicated the reinfection. After overall follow-up 17 patients (17%) underwent re-revision surgery, 11 patients (11%) due to an infection and 6 patients (6%) for aseptic reasons. Conclusions: Treatment of a (suspected) infection of a TKA by a two-stage revision had acceptable results based on re-revision and re-infection rates in the long term (>5 years), resembling the short-term results (<2 years). Focussing on the cultures at the index two-stage revision, episodes of relapse and new infections during follow-up were almost equally divided. Reinfection rates were higher in cases with positive cultures at reimplantation. Patients should be counselled appropriately in this particular situation.

Evaluation One Year after DAIR Treatment in 91 Suspected Early Prosthetic Joint Infections in Primary Knee and Hip Arthroplasty.

INTRODUCTION: Early recognition and appropriate initial treatment with debridement, antibiotics and implant retention (DAIR) if a suspicion of an early prosthetic joint infection (PJI) is present can eradicate infection on first attempt and prevent implant failure. We evaluated the outcome after 1 year of patients treated with DAIR after primary total knee arthroplasty (TKA) or total hip arthroplasty (THA). Furthermore, we determined preoperative, microbiology, and treatment factors related to failure after DAIR. METHODS: A retrospective cohort study was assembled with 91 patients undergoing DAIR with a high suspicion of an early PJI. Records were reviewed for demographics, preoperative laboratory results, microbiological data, given treatment and postoperative follow-up. The primary outcome was infection-free implant survival at 1 year. Repeated DAIR was not considered as treatment failure. RESULTS: The rate of infection-free implant survival following DAIR in a suspected early PJI was 85% (95% confidence intervals (CI) 78-91). Cultures remained negative in 20 patients, with no occurrence of infection during follow-up. A higher failure rate was seen in early PJI caused by Enterococcus faecalis (p=0.04). Multivariate analysis showed a statistically significant association between treatment failure and high C-reactive protein level (CRP >100) (odds ratio 10.0, 95% CI [1.5-70]) and multiple DAIR procedures (≥2) (odds ratio 5.0, 95%CI [1.1-23]). CONCLUSION: If an early PJI is suspected DAIR is the appointed treatment with up to 2 debridement procedures. Since culture-negative DAIRs were not related to any complications during follow-up, overtreatment of suspected PJI seems to do no significant harm with respect to implant failure.

Low sensitivity of implant sonication when screening for infection in revision surgery.

Background and purpose - Prosthetic-joint infection (PJI) is the most serious complication of arthroplasty, and accurate identification of a potentially responsible microorganism is essential for successful antibiotic treatment. We therefore determined the diagnostic accuracy of sonication and compared it with tissue culture as a screening tool in detecting prosthetic joint infection in revision arthroplasty. Patients and methods - 252 consecutive revision arthroplasty cases were enrolled. These cases were determined as being suspected or unsuspected of having infection according to standard criteria. Perioperatively, 6 periprosthetic interface tissue biopsies were obtained from each patient and the implants removed were sonicated. The sensitivity and specificity of periprosthetic tissue culture and sonication fluid cultures were determined. Results - Preoperatively, 75 revision cases were classified as having PJI (33 early and 42 late) and 177 were unsuspected of having infection. Compared with tissue culture, the sensitivity of the sonication fluid analysis was low: 0.47 (95% CI: 0.35-0.59) for sonication as compared to 0.68 (95% CI: 0.56-0.78) for tissue culture. The specificity of the sonication fluid analysis was higher than that for tissue culture: 0.99 (95% CI: 0.96-1.0) as compared to 0.80 (95% CI: 0.74-0.86). Interpretation - Sonication is a highly specific test for diagnosis of PJI. However, due to the low sensitivity, a negative sonication result does not rule out the presence of PJI. Thus, sonication is not of value for screening of microorganisms during revision surgery.

Long-term outcomes of the Bi-Metric proximally hydroxyapatite-coated femoral stem.

PURPOSE: Promising clinical results and survival rates have been reported for the Bi-Metric proximally hydroxyapatite (HA)-coated femoral stem in short- and mid-term studies. In this study we evaluated the long-term survival as well as clinical and radiological results of this stem. METHODS: From 1992 to 1998 we prospectively included 112 consecutive patients who received a total hip arthroplasty (THA) with an uncemented proximally HA-coated Bi-Metric femoral component (Biomet).At 3 months, 1 year and thereafter every 2 to 3 years, patients were clinically and radiologically monitored. Primary endpoint was revision of the stem for any reason. Secondary endpoints were survival of the cup and THA, radiological characteristics and clinical scores (HHS, HOOS, SF-36 and VAS). RESULTS: Median follow-up was 20 (16-22.25) years. Median age at surgery was 52 (22-63) years. At final follow-up, survival analysis showed an all-cause stem survival of 96.8% (95% CI, 93.3-100). Median HHS scores improved from 57 preoperatively to 94 at final follow-up (p<0.001). At final follow-up the median HOOS score was 80 (9-100); median SF-36 score 71 (18-100); median VAS pain score at rest 0 (0-6) and during activity 0 (0-10). CONCLUSIONS: In this prospective cohort study the 20-year survival rate of the Bi-Metric proximally HA-coated femoral stem was excellent.

Treatment of prosthetic joint infections due to Propionibacterium. Similar results in 60 patients treated with and without rifampicin.

BACKGROUND AND PURPOSE: Currently, Propionibacterium is frequently recognized as a causative microorganism of prosthetic joint infection (PJI). We assessed treatment success at 1- and 2-year follow-up after treatment of Propionibacterium-associated PJI of the shoulder, hip, and knee. Furthermore, we attempted to determine whether postoperative treatment with rifampicin is favorable. PATIENTS AND METHODS: We conducted a retrospective cohort study in which we included patients with a primary or revision joint arthroplasty of the shoulder, hip, or knee who were diagnosed with a Propionibacterium-associated PJI between November 2008 and February 2013 and who had been followed up for at least 1 year. RESULTS: We identified 60 patients with a Propionibacterium-associated PJI with a median duration of 21 (0.1-49) months until the occurrence of treatment failure. 39 patients received rifampicin combination therapy, with a success rate of 93% (95% CI: 83-97) after 1 year and 86% (CI: 71-93) after 2 years. The success rate was similar in patients who were treated with rifampicin and those who were not. INTERPRETATION: Propionibacterium-associated PJI treated with surgery in combination with long-term antibiotic administration had a successful outcome at 1- and 2-year follow-up irrespective of whether the patient was treated with rifampicin. Prospective studies are needed to determine whether the use of rifampicin is beneficial in the treatment of Propionibacterium-associated PJI.

Finding the right hip implant for patient and surgeon: the Dutch strategy--empowering patients.

We describe the implementation process of hip prostheses selection in the Netherlands. The recent problems with large head metal-on-metal hip prostheses resulted in substantial damage to the surgeons' credibility and reputation in the media. This led to a true sense of urgency among orthopaedic surgeons to increase their activities to secure patient safety. The board of the Dutch Orthopaedic Association (NOV) in the Netherlands established a Dutch Hip Task Force (DHTF) with the explicit assignment of formulating criteria to classify the quality of total hip implants on the Dutch market based on survivorship. The aim was to offer unequivocal information enabling a balanced choice of total hip prosthesis. The ultimate goal of the NOV is that all implanted total hip prostheses implanted in the Netherlands are based on reliable clinical evidence. The DHTF decided to adapt the principles of the National Institute for Health and Care Excellence (NICE, UK) (www.nice.org.uk). The taskforce uses data from the registries as well as the Orthopaedic Data Evaluation Panel (ODEP). If the ODEP guidelines had been chosen as standard alone, one quarter of our listed hip components would not have been included. In our view this underlines the strength in the Dutch approach where high quality registry data and ODEP ratings are complementary and result in a list of reliable hip prostheses. Most importantly we offer patients insights into the known quality of the implants by sharing the results of our implant review. This will facilitate shared decision making by empowering patients in their knowledge on available hip arthroplasties.

Insert dissociation after fixed bearing PS constrained Genesis II total knee arthroplasty. A case series of nine patients.

Dissociation of the polyethylene insert after fixed bearing posterior stabilized Genesis II total knee arthroplasty has been rarely described. We present a case series of nine patients with a dissociation of the insert within a period of two years after surgery. Revision surgery was performed in all patients. In this report we discuss clinical presentation, patient characteristics and possible etiologies for tibial insert dissociation seen in the presented cases. In conclusion, tibial insert dissociation does not lead to a uniform clinical presentation. Therefore, in this point of view regular physical examination and imaging after TKA regardless the presence of symptoms seems to be indicated.