Search

Extracellular vesicles (EVs) comprise an as yet insufficiently investigated intercellular communication pathway in the field of revision total joint arthroplasty (RTJA). This study examined whether periprosthetic joint synovial fluid contains EVs, developed a protocol for their isolation and characterized them with respect to quantity, size, surface markers as well as documented their differences between aseptic implant failure (AIF) and periprosthetic joint infection (PJI). EV isolation was accomplished using ultracentrifugation, electron microscopy (EM) and nanoparticle tracking analysis evaluated EV presence as well as particle size and quantity. EV surface markers were studied by a bead-based multiplex analysis. Using our protocol, EM confirmed the presence of EVs in periprosthetic joint synovial fluid. Higher EV particle concentrations and decreased particle sizes were apparent for PJI. Multiplex analysis confirmed EV-typical surface epitopes and revealed upregulated CD44 and HLA-DR/DP/DQ for AIF, as well as increased CD40 and CD105. Our protocol achieved isolation of EVs from periprosthetic joint synovial fluid, confirmed by EM and multiplex analysis. Characterization was documented with respect to size, concentration and epitope surface signature. Our results indicate various differences between PJI and AIF EVs. This pilot study enables new research approaches and rising diagnostic opportunities in the field of RTJA.

Immunology, already a discipline in its own right, has become a major part of many different medical fields. However, its relationship to orthopedics and trauma surgery has unfortunately, and perhaps unjustly, been developing rather slowly. Discoveries in recent years have emphasized the immense breadth of communication and connection between both systems and, importantly, the highly promising therapeutic opportunities. Recent discoveries of factors originally assigned to the immune system have now also been shown to have a significant impact on bone health and disease, which has greatly changed how we approach treatment of bone pathologies. In case of bone fracture, immune cells, especially macrophages, are present throughout the whole healing process, assure defense against pathogens and discharge a complex variety of effectors to regulate bone modeling. In rheumatoid arthritis and osteoporosis, the immune system contributes to the formation of the pathological and chronic conditions. Fascinatingly, prosthesis failure is not at all solely a mechanical problem of improper strain but works in conjunction with an active contribution of the immune system as a reaction to irritant debris from material wear. Unraveling conjoined mechanisms of the immune and osseous systems heralds therapeutic possibilities for ailments of both. Contemplation of the bone as merely an unchanging support pillar is outdated and obsolete. Instead it is mandatory that this highly diverse network be incorporated in our understanding of the immune system and hematopoiesis.

Acetabular revision of failed total hip arthroplasty (THA) is often associated with severe bone loss. Therefore, a variety of revision implant systems has been developed during recent years, with the augment-and-modular-cage system being one of the newest additions to this portfolio. Together with biologic downsizing by means of impaction bone grafting, this uncemented system promises a high modularity and versatility to treat all acetabular defects up to Paprosky types IIIa and IIIb without pelvic discontinuity. The aim of the present study was to evaluate first short-term results of its clinical application, both clinical functional and patient-reported as well as radiographic. Forty-four patients (28 female, 16 male, mean age 70.9 ± 11.5 years) could be followed for a mean of 26 ± 10 months after acetabular revision with a novel augment-and-modular-cage system. Indications for revision included aseptic loosening (68%), septic loosening (16%), or others (16%) with bone loss Paprosky IIa up to IIIb without discontinuity. The modified Harris Hip Score (mHHS) served as a primary outcome parameter. In addition, a number of patient-reported outcome measurements (PROMs) were collected including the Short Form 36 (SF-36), Hip disability and Osteoarthritis Outcome Score (HOOS), and Visual Analogue Scale for Hip Pain (VAS Hip) as well as overall satisfaction. Radiographic changes between the pre- and postoperative center of rotation (COR) and various criteria of implant failure served as secondary outcome parameters. No patients were lost to follow-up. Two implant-associated complications (partial flange breakage) without a need for revision surgery were detected, which represent a failure rate of 4.5%. Functional outcome as measured by mHHS increased from 49.4 ± 2.9 pre-operatively to 74.4 ± 3.1 at the latest follow-up (p

Musculoskeletal hydatidosis is a rare but severe disease in central Europe. This case report presents the incidental finding of an osseous hydatidosis after cementless revision total hip arthroplasty in a patient without a preoperative history of hydatidosis or any clinical symptoms. Revision total hip arthroplasty had been necessary due to a septic osteonecrosis of the femoral head 2 years after osteosynthesis of a traumatic proximal femur fracture with a sliding hip screw. The positive sample was taken out of the greater trochanter in the area of the possible former entry point for the lag screw, which was macroscopic inconspicuous. Sero-analysis could afterwards confirm the suspected diagnosis. Postoperative chemotherapy with albendazole was performed for 6 months. A full-body MRI did not reveal any further cysts. This case demonstrates a possible impact of migration on the expected pathogens in revision arthroplasty. This demonstrates that in revision arthroplasty, an infection with this parasite also has to be taken into account, if the patients come from an area endemic for hydatidosis.

Failed total knee arthroplasty (TKA) with significant bone loss and compromised soft-tissues is challenging and the final results are often inferior to patient’s expectation. The objective of this study was to present a comparison of outcomes in patients with failed infected TKA treated with two-stage revision TKA or knee arthrodesis and to assess clinical and functional results, implant survival and infection recurrence. The hypothesis was that an arthrodesis may result in beneficial effects on patients’ outcome. Clinical data of 81 patients with periprosthetic joint infection (PJI) of the knee joint were collected and analyzed retrospectively. Between 2008 and 2014, a total of 36 patients had been treated within a two-stage exchange procedure and reimplantation of a modular intramedullary arthodesis nail and 45 patients with revision TKA. Patients were treated according to the same structured treatment algorithm. Clinical and functional evaluation was performed using the Oxford knee score (OKS) and the visual analogue scale (VAS). The mean follow-up was 32.9 ± 14.0 months. The rate of definitely free of infection at last follow-up in the arthrodesis group was 32 of 36 (88.9%) and 36 of 45 (80.0%) in the revision TKA group (p = 0.272). Mean VAS for pain in the arthrodesis group was 3.1 ± 1.4 compared to 3.2 ± 1.6 in the revision TKA group (p = 0.636). The OKS in the arthrodesis group was 38.7 ± 8.9 and 36.5 ± 8.9 (p = 0.246) in patients with revision TKA. Rate of revisions in the revision-TKA group was 2.8 ± 3.7 compared to 1.2 ± 2.4 in the arthrodesis group (p = 0.021). Treatment of PJI needs a distinct therapy with possible fallback strategies in case of failure. A knee arthrodesis is a limb salvage procedure that showed no significant benefits on the considered outcome factors compared to revision TKA but is associated with significantly lower revision rate. After exhausted treatment modalities, a knee arthrodesis should be considered as an option in selected patients. Level III, retrospective cohort study.

Periprosthetic shoulder infection (PSI) remains a devastating complication after total shoulder arthroplasty (TSA). Furthermore, there is a paucity in the literature regarding its diagnostic and therapeutic management, especially the absence of therapy concepts devised exclusively for PSI. The aim of the presenting study is to examine the characteristics and outcome of patients with PSI who were treated according to well-established algorithms developed originally for periprosthetic joint infection (PJI) of the hip and knee and determine if these algorithms can be applied to PSI. This single-center case series included all patients with a PSI presenting between 2010 and 2020. Recorded parameters included age, sex, affected side, BMI, ASA score, Charlson comorbidity index, preoperative anticoagulation, indication for TSA (fracture, osteoarthritis or cuff-arthropathy), and type of infection (acute or chronic PSI). The outcome was divided into treatment failure or infect resolution. Staphylococcus epidermidis and aureus were the commonest infecting pathogens. Acute PSI was mainly treated with debridement, irrigation, and retention of the prosthesis (DAIR) and chronic cases with two/multiple-stage exchange. The treatment failure rate was 10.5%. C-reactive protein was preoperatively elevated in 68.4% of cases. The mean number of operative revisions was 3.6 ± 2.6, and the mean total duration of antibiotic treatment was 72.4 ± 41.4 days. The most administered antibiotic was a combination of clindamycin and fluoroquinolone. In summary, the data of the current study suggest that therapeutical algorithms and recommendations developed for the treatment of PJI of the hip and knee are also applicable to PSI.

Background Periprosthetic joint infection is a serious complication and reconstruction after failed revision total knee arthroplasty with significant bone loss and compromised soft-tissues can be challenging. Objective of this study was to assess clinical and functional results, implant survival and infection recurrence rates in patients treated with two-stage arthrodesis after failed revision TKA with extensor mechanism deficiencies due to PJI, and to identify the factors that affect outcomes after surgery. Methods Thirty seven patients with PJI treated within a two-stage exchange and reimplantation of an arthrodesis nail between 2008 and 2014 were included. Systemic and local risk factors were graded preoperatively according to McPherson et al. All patients were treated according to a structured treatment algorithm. Clinical and functional evaluation was performed using the Oxford Knee Score and the Visual Analogue Scale. Results Thirty two of 37 patients (86.5%) were graded as free of infection. Five patients (13.5%) had recurrent infection after arthrodesis with the need of revision surgery. Mean leg-length discrepancy was 2.2 cm. The mean VAS for pain was three, the mean Oxford Knee Score was 38 ± 9. Total implant survival at a 74 month follow-up was 74.3% (95% CI: 45.4 to 91.1%), as determined by Kaplan–Meier survival curves. Local McPherson Score, as well as number of revisions was found to be of significant influence to the survival rate. Conclusions Septic failure of revision knee arthroplasty can be effectively treated with two-stage arthrodesis using a modular intramedullary nail, providing a stable and painless limb with satisfactory functional results and acceptable infection eradication rates.

AIM To assess serum levels of RANK-ligand (RANKL) and osteoprotegerin (OPG) as biomarkers for periprosthetic joint infection (PJI) and compare their accuracy with standard tests. METHODS One hundred and twenty patients presenting with a painful total knee or hip arthroplasty with indication for surgical revision were included in this prospective clinical trial. Based on standard diagnostics (joint aspirate, microbiological, and histological samples) and Musculoskeletal Infection Society consensus classification, patients were categorized into PJI, aseptic loosening, and control groups. Implant loosening was assessed radiographically and intraoperatively. Preoperative serum samples were collected and analyzed for RANKL, OPG, calcium, phosphate, alkaline phosphatase (AP), and the bone-specific subform of AP (bAP). Statistical analysis was carried out, testing for significant differences between the three groups and between stable and loose implants. RESULTS All three groups were identical in regards to age, gender, and joint distribution. No statistically significant differences in the serum concentration of RANKL (P = 0.16) and OPG (P = 0.45) were found between aseptic loosening and PJI, with a trend towards lower RANKL concentrations and higher OPG concentrations in the PJI group. The RANKL/OPG ratio was significant for the comparison between PJI and non-PJI (P = 0.005). A ratio > 60 ruled out PJI in all cases (specificity: 100%, 95%CI: 89, 11% to 100.0%) but only 30% of non-PJI patients crossed this threshold. The positive predictive value remained poor at any cut-off. In the differentiation between stable and loose implants, none of the parameters measured (calcium, phosphate, AP, and bAP) showed a significant difference, and only AP and bAP measurements showed a tendency towards higher values in the loosened group (with P = 0.09 for AP and P = 0.19 for bAP). CONCLUSION Lower RANKL and higher OPG concentrations could be detected in PJI, without statistical significance.

Hintergrund Periazetabulare Defekte stellen weiterhin eine grose Herausforderung in der Revisionsendoprothetik des Huftgelenkes dar. Neben der Klassifikation der Defektsituation mit Auswahl des geeigneten Revisionsimplantates ist neben der primarstabilen Verankerung der Implantate der suffiziente biologische Wiederaufbau des Defektes mit Wiederherstellung eines tragfahigen Implantatlagers essenziell fur den Langzeiterfolg der azetabularen Revisionschirurgie. Die biologische Defektrekonstruktion verfolgt das Ziel eines „Downsizing“ des periazetabularen Defektes vor dem Hintergrund moglicher zukunftiger Revisionsoperationen.

Diagnosing a (low-grade) periprosthetic joint infection (PJI) after hip or knee arthroplasty remains a diagnostic challenge. The aim of this study was to evaluate the utility of using a novel multiplex protein microarray system for synovial biomarkers in determining PJI in patients undergoing revision knee or hip arthroplasty. The individual synovial fluid levels of 12 cytokines (IL-1b, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12, IL-17, GM-CSF, TNF-α, and INF-γ) were analysed with a novel multiplex protein microarray system in 32 patients undergoing revision hip (n = 22) or knee (n = 10) arthroplasty. Cases were classified into septic and aseptic groups on basis of pre- and interoperative findings: [PJI (n = 14) vs. non-PJI (n = 18)]. Receiver operator characteristic (ROC) curves were calculated to assess the discriminatory strength of the individual parameters. A multiple regression model was used to determine the utility of using a combination of the tested cytokines to determine the infection status. The levels of all of the evaluated cytokines were significantly elevated in the PJI-group. Best sensitivity and specificity were found for IL-6, followed by IL-1b, IL-10, and IL-17. The multiple regression models revealed a combination of IL-2, IL-4, IL-5, IL6, lL-12, and GM-CSF to be associated with the best sensitivity (100%) and specificity (88.9%) for a cut-off value of 0.41, with a likelihood ratio of 9.0. Analysis of individual synovial fluid cytokine levels showed both high sensitivity and high specificity in diagnosing PJI. A combined model using several cytokines showed even higher sensitivity and specificity in diagnosing PJI and could thus be a useful predictive tool to determine the probability of PJI in patients with a painful prosthesis. Diagnostic IV.

Background Custom-made acetabular components (CMAC) are one established method to address severe acetabular bone defects. Monoflanged CMAC may represent an advantageous alternative to establish triflanged CMAC as they promote better primary stability through metallic defect reconstruction and thus anatomic restoration of the center of rotation (COR). Methods Fifty-eight consecutive (21 triflanged and 37 monoflanged) CMAC were evaluated for overall survival, reasons for revision, radiological restoration of COR, and clinical outcome parameters. Results There were no significant differences between both design types regarding overall survival, revision rates, Harris Hip Score, or visual analog scale (pain) score at latest follow-up (mean, 56.3 ± 28.7 months). Triflanged CMAC showed a significant lateralization (P ≤ .001) and cranialization (P = .003) of the COR compared to the contralateral side. Monoflanged CMAC restored the anatomic COR. Reasons for revision surgery and explantation were periprosthetic joint infection (n = 12) and aseptic loosening (n = 2) without significant differences between both groups. Conclusion Monoflanged CMAC demonstrate similar clinical outcome parameters and survival rates as triflanged CMAC but superior biomechanical features and represent therefore a solid alternative treatment option and implant design.

Severe acetabular bone loss, both with or without pelvic discontinuity, remains a challenge in revision total hip arthroplasty (RTHA). The goal of our study was to evaluate the mid-term results for consecutive patients with Paprosky III acetabular bone loss with or without pelvic discontinuity who needed RTHA with custom-made acetabular implants and to compare the results to those of other studies. Sixty-eight (68) patients with severe acetabular bone loss (Paprosky Type IIIa and IIIb), who required RTHA, were included in our study. All prostheses were constructed on the basis of thin-layer computed tomography (CT) scans of the pelvis. The visual analogue scale (VAS), Harrison hip score (HHS), and clinical and radiographic follow-up assessments were used to evaluate the outcome. The average follow-up time was 43 months (range 1–120 months). Implant survival at last follow-up was 75% (51 of 68). Kaplan–Meier survival analysis, with explantation as the endpoint, revealed survival rates of 82.7% (3 years) and 77% (5 years). Patients with revision of the acetabular component only had a significant higher survival rate (p 0.012). Overall revision rate was 36.7%. Reinfection rate was 34.4%. Complications included 15 (22%) periprosthetic joint infections (PJI), 7 dislocations (10.2%), and 2 aseptic loosenings (2.9%). Mean VAS at last follow-up was 1.45 compared to 3.2 preoperatively, while mean HHS improved from 21.1 points preoperatively to 61 at last follow-up. The change in both scores was thus significant (p

Background In our recent clinical trial, increased peripheral concentrations of pro-inflammatory molecular mediators were determined in complex regional pain syndrome (CRPS) patients. After 3 months adjunctive unilateral, selective L4 dorsal root ganglion stimulation (L4-DRGSTIM), significantly decreased serum IL-10 and increased saliva oxytocin levels were assessed along with an improved pain and functional state. The current study extended molecular profiling towards gene expression analysis of genes known to be involved in the gonadotropin releasing hormone receptor and neuroinflammatory (cytokines/chemokines) signaling pathways. Methods Blood samples were collected from 12 CRPS patients for whole-transcriptome profiling in order to assay 18,845 inflammation-associated genes from frozen blood at baseline and after 3 months L4-DRGSTIM using PANTHER™ pathway enrichment analysis tool. Results Pathway enrichment analyses tools (GOrilla™ and PANTHER™) showed predominant involvement of inflammation mediated by chemokines/cytokines and gonadotropin releasing hormone receptor pathways. Further, screening of differentially regulated genes showed changes in innate immune response related genes. Transcriptomic analysis showed that 21 genes (predominantly immunoinflammatory) were significantly changed after L4-DRGSTIM. Seven genes including TLR1, FFAR2, IL1RAP, ILRN, C5, PKB and IL18 were down regulated and fourteen genes including CXCL2, CCL11, IL36G, CRP, SCGB1A1, IL-17F, TNFRSF4, PLA2G2A, CREB3L3, ADAMTS12, IL1F10, NOX1, CHIA and BDKRB1 were upregulated. Conclusions In our sub-group analysis of L4-DRGSTIM treated CRPS patients, we found either upregulated or downregulated genes involved in immunoinflammatory circuits relevant for the pathophysiology of CRPS indicating a possible relation. However, large biobank-based approaches are recommended to establish genetic phenotyping as a quantitative outcome measure in CRPS patients. Trial registration The study protocol was registered at the 15.11.2016 on German Register for Clinical Trials (DRKS ID 00011267). https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00011267

Introduction Long-established extensor mechanism insufficiency that defies reconstruction is a rare, but devastating, complication after revision total knee arthroplasty (RTKA) that may require arthrodesis. For cemented stem guided knee prostheses with firmly attached stems, prosthesis explantation can lead to significant bone stock loss that may, at worst, make knee arthrodesis significantly more difficult or impossible to achieve. Under these circumstances, conversion of the cemented knee prosthesis with custom-made arthrodesis modules that preserve the existing stem anchorage may be a low-risk alternative. This case series presents this type of conversion to arthrodesis, which was performed for patients with a non-reconstructable, long-established extensor mechanism insufficiency. Methods After intraoperatively ascertaining that reconstruction of the extensor mechanism insufficiency was impossible, the inlying revision prosthesis was converted into arthrodesis with custom-made arthrodesis modules, without explanting the cemented stems. Results Conversion to arthrodesis was performed in four patients. There was no histopathological or microbiological evidence of a periprosthetic joint infection. Clinical follow-up showed a low level of pain, with a stable knee joint and proper implant position. The Oxford Knee Score increased from 20.5 (95% CI 17–26) to 35.5 (95% CI 30–36) points. The visual analog scale decreased from 5.5 (95% CI 4–7) pre-operatively to 1.5 (95% CI 1–2) points at last follow-up. No implant-specific complications occurred. Conclusions Conversion of cemented RTKA with firmly attached cemented stems, without evidence of loosening, to arthrodesis might be a surgical treatment strategy for patients with a long-established extensor mechanism insufficiency that cannot be reconstructed.

BACKGROUND When deciding upon the best treatment strategy in revision arthroplasty, it is absolutely crucial to use the best possible preoperative detection whether a periprosthetic joint infection (PJI) is present or not. New molecular markers investigated in serum samples and synovial fluid can help to improve the preoperative diagnosis. In 2001, a novel IL-6 lateral flow immunoassay testing device was introduced which has never been tested in synovial fluid so far. OBJECTIVE For our study we investigated whether the test can be used safely, feasibly and time effectively with synovial fluid gathered from potentially infected THAs or TKAs and whether the already published cutoff for IL-6 in synovial fluid predicting a PJI can be reproduced using the QuickLine IL-6 immunoassay. METHODS After ethic approval and within the scope of a prospective controlled trial we investigated 26 patients (m = 9, 34.6%; f= 17, 65.4%) with n = 13 (50%) potentially infected total hip arthroplasties (THAs) and n = 13 (50%) suspected PJIs of total knee arthroplasties (TKAs). Sterile aspirated synovial fluid was examined for total leukocyte count and cell differentiation by a blood count analyzer in body fluid mode as well as for IL-6 (Immulite, Siemens Medical Solutions Diagnostics GmbH, Eschborn, Germany). Another part of the joint aspirate was tested using the QuickLine IL-6 Test by Milenia Biotec (Milenia Biotec, Giesen, Germany). RESULTS The mean concentration of IL-6 as determined from our reference laboratory testing (Siemens Immulight) for aseptic cases was 1,219 pg/mL (SD 1,369 pg/mL, min 134 pg/mL-max 4,214 pg/mL). The mean IL-6 concentration measured via the IL-6 QuickLine for aseptic cases was 410 pg/mL (SD 371 pg/mL, min 100 pg/mL-max 1562 pg/mL). The test showed no false negative or false positive results in the cases tested. In six patients, PJI was considered proven. The QuickLine Test indicated IL 6 concentrations > 10,000 pg/mL in these cases without further quantification above this maximum detection threshold. Results from the QuickLine Test and the laboratory tests were matched and a non-linear best fit curve (log-log-curve) was applied. The subsequent Spearman correlation showed a correlation coefficient of r = 0.92 (95% CI 0.81-0.97) which corresponds to a two-tailed p-value of < 0.0001, respectively. As a primary finding we were able to show that the Milenia QuickLine IL-6 Test can be used safely, feasibly and time effectively with synovial fluid gathered intraoperatively from potentially infected THAs or TKAs. The test as provided worked well in 84.6% of the samples tested and failed only due to very viscous synovial fluid. As a secondary result we found that the previously published cut-off for IL-6 in synovial fluid predicting a PJI with a sensitivity of 46.88% and a specificity of 97.62% can be reproduced using the QuickLine IL-6 immunoassay. CONCLUSION Taking the limitations of the low sample size as a given this relatively simple point of care (POC) assay showed promising results in our pilot trial and may help diagnosing PJI. It may help physicians and surgeons to choose the best and least invasive treatment strategy for patients presenting with painful arthroplasty.

Einleitung: Bei grosen und gelenknahen knochernen Defektsituationen nach vorangegangenen revisionsendoprothetischen Eingriffen besteht im Fall des erneuten Versagens die Moglichkeit der Versorgung durch modulare Implantatsysteme aus der tumorendoprothetischen Versorgung als sog. „Salvage Procedure“. Das Ziel der vorliegenden retrospektiven Studie ist die Evaluation von Patienten, die aufgrund groser und gelenknaher knocherner Defektsituationen, welche nicht mit konventionellen Implantatsystemen versorgt werden konnten, hinsichtlich des klinisch-funktionellen Outcomes und der Komplikationsrate nach Implantation eines modularen Tumor- und Revisionssystems (MUTARS®, Firma Implantcast, Buxtehude, Deutschland). Methodik: In unserer Klinik wurden im Zeitraum von 2005 bis 2014 insgesamt 25 Patienten mittels des MUTARS-Systems aufgrund einer konventionell nicht zu versorgenden ossaren Defektsituation operativ revidiert. Der mittlere Nachbeobachtungszeitraum lag bei 16 Monaten (Spannweite: 12–72 Monate). Folgende Indikationen fuhrten zum Revisionseingriff: Ein Patient stellte sich aufgrund einer gelockerten Kappenprothese mit Bildung eines Metallgranuloms vor, 2 Patienten mit einer Pseudarthrose nach Implantation eines Femurnagels, ein Patient mit einem „Cut-Out“ eines Femurnagels. Vier Patienten mussten aufgrund einer aseptischen und ein Patient aufgrund einer septischen Lockerung einer zuvor implantierten Endoprothese revidiert werden. Insgesamt wurden 6 Patienten aufgrund einer periprothetischen Fraktur revidiert. Weitere 10 Patienten wurden bei einer infektkonsolidierten Girdlestone-Situation nach Explantation einer Endoprothese aufgrund eines periprothetischen Infekts versorgt. Alle Patienten wurden in regelmasigen Intervallen klinisch und radiologisch reevaluiert. Es wurden neben den Komorbiditaten der Patienten klinisch funktionelle-Parameter wie der Harris Hip Score erfasst. Des Weiteren wurde eine Outcome-Analyse bezuglich peri- und postoperativer Komplikationen und eine nativradiologische Verlaufsbeurteilung durchgefuhrt. Ergebnisse: Insgesamt wurden 23 Patienten mit einem proximalen Femur versorgt. Drei Patienten erhielten zusatzlich zur Tumorprothese einen Beckenteilersatz aufgrund einer Beckendiskontinuitat. Ein Patient wurde mit einem distalen Femur, und bei einem weiteren Patienten wurde das ganze Femur durch einen totalen Femurersatz endoprothetisch ersetzt. Die mittlere Krankenhausverweildauer lag bei 25 Tagen (Spannweite: 11–47 Tage). Wir verzeichneten eine Komplikationsrate von 24 %. Der Harris Hip Score stieg von 28 Punkten praoperativ auf 81 Punkte postoperativ. Schlussfolgerung: Bei hohergradigen, knochernen und gelenknahen Defektsituationen nach vorangegangener, gescheiterter endoprothetischer oder osteosynthetischer Versorgung, bietet das MUTARS-System eine suffiziente Versorgungsmoglichkeit mit modularer Adaptation an die jeweilige individuelle Defektkonstellation des Patienten. Die klinischen Ergebnisse sind im kurz- bis mittelfristigen Verlauf vielversprechend.

Periprosthetic joint infection (PJI) is one of the most challenging complications in orthopedic surgery. In cases of suspected periprosthetic joint infection several diagnostic methods are available. In this study we investigated the performance of the newly available Unyvero i60 implant and tissue infection (ITI) multiplex PCR System. 62 specimens from 31 patients with suspected PJI or aseptic loosening of a painful joint arthoplasty were included in this study. Besides the established diagnostic procedures we included a commercial multiplex PCR detection system for diagnosis of PJI. The PCR results obtained from analysis of sonication and synovial fluids (62 specimens) showed a sensitivity of 66.7%, a specificity of 100%, a positive predictive value (PPV) of 100% and a negative predictive value (NPV) of 68.4% when compared to cultural methods. Notably, cultures from sonication fluid displayed a sensitivity of 88.9%, a specificity of 61.5%, a PPV of 76.2% and a NPV of 80.0% when compared to tissue cultures. In conclusion, multiplex PCR is an additional - rapid - method for diagnosing PJI. Positive results with the PCR assay used in this study were always confirmed by subsequent matching culture positivity. However, apart from the time saved the nucleic acid amplification technique did not yield additional information than that obtained from microbiological cultures.

Total joint arthroplasty is a common operation worldwide with infection rates between 1% and 3%. In cases of suspected periprosthetic joint infection, it is very challenging to rule out the causative microorganisms. In this study, we compared the appearance of periprosthetic membranes with the microbiological results obtained from cultures of sonication fluid and the correlation between classical microbiological cultures and cultures of sonication fluid. The results confirmed a strong correlation of bacterial growth in sonication fluid cultures with bacterial growth in classical microbiological cultures. Most importantly, however, our study documented a highly significant correlation of periprosthetic membranes typical for periprosthetic joint infection (PJI) with bacterial growth in sonication fluid. Sonication fluid cultures yielded a better sensitivity than tissue cultures (72.34-60.87%). These 3 methods are useful tools in diagnosing PJIs, and even more, sonication fluid cultures should be included in the diagnostic path of PJI.

Leider wurde bei dem ursprunglichen Beitrag der Name des Autors D. C. Wirtz nicht korrekt genannt. Wir bitten, die Korrektur zu beachten, und entschuldigen uns fur den …

Accurate diagnosis of periprosthetic joint infections (PJI) is one of the most widely researched areas in modern orthopedic endoprosthesis. However, our understanding of the immunological basis of this severe complication is still limited. In this study, we developed a flow cytometric approach to precisely characterize the immune cell composition in periprosthetic joints. Using high-dimensional multi-parametric data, we defined, for the first time, the local immune cell populations of artificial joints. We identified significant differences in the cellular distribution between infected and non-infected samples, and revealed that myeloid-derived suppressor cells (MDSCs) act as potential regulators of infiltrating immune cells in PJI. Further, we developed an algorithm to predict septic and aseptic samples with high sensitivity and specificity, that may serve as an indispensable addition to the current criteria of the Musculoskeletal Infection Society. This study describes a novel approach to flow cytometrically analyze the immune cell infiltrate of joint fluid that not only improves our understanding of the pathophysiology of PJI, but also enables the development of a novel screening tool to predict infection status. Our data further suggest that pharmacological targeting of MDSCs represents a novel strategy for addressing PJI.

Zusammenfassung: Operationsziel: Ziel der Therapie ist die mechanische und funktionelle Stabilisation einer hohen Hüftluxation bei dysplasiebedingter Coxarthrose mittels endoprothetischem Ersatz. Indikationen: Hüftdysplasie im Erwachsenenalter. Fortgeschrittene symptomatische Coxarthrose. Hohe Hüftluxation gemäß CroweIII/IV. Symptomatische Beinlängendifferenz. Kontraindikationen: Zerebrospinale Dysfunktionen. Muskeldystrophien. Manifeste Störung des Knochenmetabolismus. Infektion. Immunsupprimierte Patienten. Operationstechnik: Seitenlage (variabel). Gerade laterale Inzision über dem Trochanter major und Eingehen zwischen dem Vorderrand des M.gluteus maximus und dem Hinterrand des M.gluteus medius, dem sog. Gibson-Intervall. Darstellen des N.ischiadicus und permanente Kontrolle desselben, um hier bei jeglichen Manipulationen, vor allem bei der Reposition des Femurs, einen Traktionsschaden aufgrund erhöhter Spannung zu vermeiden. Trochanter-Flip-Osteotomie und Darstellen der Gelenkkapsel zwischen M.piriformis und M.gluteus minimus. Aufgrund des Hochstands des Femurs kann hier die Identifikation der anatomischen Landmarken erschwert sein. Schrittweise Z-förmige Kapsulektomie der elongierten Kapsel und Darstellen der Primärpfanne, die häufig aufgrund der langzeitigen Luxation des Femurkopfs nur rudimentär ausgebildet ist. Lokalisation des Pfannengrunds bzw. der Tränenfigur. Aufraspeln der Pfanne und Implantation der mit der Pfannengröße konformen Hakendachschale. Fixation der Pfanne je nach Halt und Knochenqualität mit 3-5Schrauben. Resektion des proximalen Femurs je nach Spannung der Weichteile bis auf Höhe oder sogar unter das Niveau des Trochanter minor. Anschließend Aufraspeln des Femurs und unter steter Spannungskontrolle des N.ischiadicus Reposition des Femurs in die Hüftpfanne; je nach Spannung des N.ischiadicus und der umgebenden Weichteile erfolgt eine Nachresektion des proximalen Femurs. Anfrischen des proximalen Femurs mit dem Meißel zur besseren Konsolidation des Trochanter-major-Fragments. Refixation des Trochanters mittels Cerclage, wobei die Muskulatur des M.gluteus medius an seinem Ursprung am Os ilium oder am muskulotendinösen Übergang am Trochanterfragment etwas mobilisiert werden muss, um den Trochanter major wieder distal am proximalen Femur refixieren zu können. Weiterbehandlung: Während der Hospitalisierung regelmäßige Behandlung auf der passiven Bewegungsschiene mit maximal 70° Flexion. Keine aktive Abduktion, keine passive Adduktion über die Mittellinie, kein Heben des gestreckten Beins, 10-15kg Teilbelastung an zwei Unterarmgehstöcken während 8Wochen. Je nach Compliance des Patienten und intraoperativer Stabilität der Prothese trägt der Patient eine Antiluxationsbandage (in Bern Hohmann-Bandage) für die ersten 6-8Wochen postoperativ. Anschließend erste klinische und radiologische Nachkontrolle und je nach Konsolidation des Trochanter major schrittweiser Übergang zur Vollbelastung. Thromboseprophylaxe bis zur Vollbelastung. Ergebnisse: Im beobachteten Zeitraum von 1998-2012 erfolgten insgesamt 28Hüftprothesenimplantationen bei hoher Hüftluxation im Erwachsenenalter im Stadium CroweIV, die mit einer Hakendachschale und einer femoralen Verkürzungsosteotomie behandelt wurden. Aktuell liegen von 14Patienten nach 8 ± 1,2Jahren (3,5-12Jahren) klinische Nachuntersuchungen vor. In diesem mittleren Beobachtungszeitraum zeigten sich gemäß Merle-d'Aubigné-Score bei 86 % der operierten Patienten Verbesserungen. Gute bis exzellente Resultate wurden in 71 % der Fälle erreicht. Langzeitergebnisse (

Periprosthetic joint infections (PJIs) are a major complication in total joint arthroplasty. Staphylococcus aureus and coagulase-negative staphylococci are known to cause the majority of all PJIs. This study aimed to analyze the eradication rates of S. aureus and S. epidermidis with methicillin susceptibility and methicillin resistance in a 2-stage therapy algorithm. Seventy-four patients with PJI caused by methicillin-resistant S. aureus (MRSA), methicillin-resistant coagulase-negative staphylococci (MRSE), methicillin-susceptible S. aureus (MSSA), and methicillin-susceptible coagulase-negative staphylococci (MSSE) were included, and the outcome was analyzed retrospectively. After a minimal follow-up of 2 years, n = 56 patients (75.7%) were definitively free of infection. The analysis revealed significant differences between the groups, with eradication rates as follows: MSSA (92.6%), MSSE (95.2%), MRSA (80%), and MRSE (54.2%). MRSE showed a significantly lower rate of patients graded as “definitively free of infection” as compared to patients with infections caused by MSSA, MSSE, and MRSA.

Prosthetic joint infections (PJI) are a serious and challenging complication after total joint arthroplasty. According to the literature, most PJI are monomicrobial infections caused by gram-positive cocci. The number of polymicrobial PJI might be underrepresented in the literature and only limited data are available regarding the outcome of polymicrobial PJI. Our hypothesis was that polymicrobial PJI are associated with a reduced cure rate compared with monomicrobial PJI. Routine clinical data were collected and analysed retrospectively as anonymised, aggregated data. A total of 77 consecutive patients with 77 confirmed PJI and proven infectious organism of the hip and knee joint treated within a two-stage exchange concept and a follow-up ≥ two years were investigated. Detection of the infectious organism was based on multiple microbiological cultures taken intra-operatively. Superficial wound swabs or swabs from sinus tracts were not taken into account. Data were grouped into polymicrobial and monomicrobial PJI. The main outcome variable was “definitively free of infection after two years” as published. Second, we considered several variables as potential confounders or as risk factors. A total of 42 men and 35 women with 46 infected total hip arthroplasties and 31 infected total knee arthroplasties were evaluated. In 37 (46.6 %) of our 77 patients a polymicrobial PJI could be detected. We found a significant association between polymicrobial PJI and the outcome parameter definitively free of infection after two years with an odds ratio (OR) of 0.3 [95 % confidence interval (CI) 0.1–1.0]. The rate of patients graded as definitively free of infection after two years was 67.6 % for polymicrobial infections vs. 87.5 % for monomicrobial infections. The American Society of Anesthesiologists (ASA) score (OR 0.4, 95 % CI 0.2–1.0, p = 0.062) was identified as a borderline significant covariable. Our data suggest that polymicrobial PJI might be underrepresented in the current literature. Additionally, the presence of multiple infectious organisms is associated with a reduced rate after two years with 67.6 vs 87.5 % for monomicrobial infections. Special attention and extra care should be considered for these patients.

The Charlson comorbidity index (CCI) was developed to quantify the influence of comorbidities on survival. The age-related CCI respects patients’ age as an additional risk factor. There are several studies available based on administrative data regarding functional outcome, implant survival, resource use and length of hospital stay in patients undergoing primary total hip arthroplasty (THA). To date, there is a lack of knowledge regarding the correlation of the CCI and the age-related CCI in case of revision total hip arthroplasty (RTHA). Our objective was to validate the influence of the CCI and age-related CCI in patients undergoing RTHA regarding complication rate, resource use implant survival and mortality rate. Between October 2007 and November 2012, 142 consecutive patients undergoing RTHA were included in this retrospective study. Routine clinical data were collected and analysed as anonymized aggregated data. In accordance to CCI and age-related CCI the rate of complications (internal medical and surgical complications), the length of hospital stay and the need for ICU treatment and the mortality rate was evaluated. Kaplan-Meier survivorship was used to determine implant survival. Twenty-one patients (15 %) had a low risk CCI, 59 patients (41 %) a moderate risk CCI and 62 patients (44 %) a high risk CCI. The mean follow-up was 27 months (range 24–70 months). In total, we recorded 57 complications (40 %), of which 45 were surgical (79 %) and 12 were internal medical complications (21 %). Twenty-four patients (17 %) had to undergo revision surgery. CCI and age-related CCI had no influence regarding implant survival. We recorded a significant influence of the age-related CCI in regard to the necessity of postoperative intensive care unit stay and the length of total hospital stay. Further we recorded a significant influence of the CCI and the age-related CCI regarding postoperative complications and internal complications, postoperative dislocation and the need for surgical revision. In summary, we conclude that the CCI and the age-related CCI are strong predictors regarding complication rate in patients undergoing RTHA. In a short- to mid-term follow-up, no influence on implant survival is detectable.

Einleitung: Die schnelle und sichere Diagnosestellung sowie Differenzierung zwischen einer aseptischen oder septischen Situation bei Knieprothesen ist weiterhin eine Herausforderung fur den behandelnden Arzt. Die Klinik, Bluttests und auch die Analyse einer Gelenkpunktion sind wichtige Parameter in der Infektdiagnostik bei periprothetischen Gelenkinfekten. Es zeigte sich jedoch, dass gegenuber der singularen Gelenkpunktion tiefe Gewebeproben aus dem Gelenk/Gelenkkapsel eine hohere Sensitivitat und Spezifitat bezuglich eines infektiosen Geschehens haben. Durch Hugle et al. wurde 2014 erstmals ein neues Instrument zur gleichzeitigen Gewebeproben- und Gelenksflussigkeitsgewinnung in einem ambulanten Umfeld beschrieben. Wir nutzen diese Methode als Teil unseres Diagnostikalgorithmus bei Patienten mit infektverdachtigen Knieprothesen. Methode: Nach Zustimmung durch die Ethikkommission wurde das Kollektiv im Rahmen einer prospektiven Studie gesammelt. Im ambulanten Rahmen konnten die Punktion und Gewebeprobengewinnung durch die retrograde Gewebestanze Retroforce® durchgefuhrt werden. Uber den standardisierten suprapatellaren lateralen Zugang des Kniegelenks, vergleichbar mit einer konventionellen Kniegelenkspunktion, erfolgte die Probengewinnung. Neben Synovialflussigkeit wurden Gewebeproben zur weiteren mikrobiologischen und histopathologischen Analyse gewonnen. Ergebnisse: Die Gewinnung von Synovialflussigkeit und Gewebeproben durch die Retroforce® bei Patienten mit infektverdachtigen Kniegelenksprothesen zeigte sich als eine praktikable, sichere und einfache Methode, welche in einem ambulanten Rahmen durchgefuhrt werden konnte.

In orthopedic patients, foreign body-associated infections, especially periprosthetic joint infections (PJIs), are a devastating complication of arthroplasty. Infection requires complex treatment, may result in long hospitalization and causes considerable costs. Multiple surgical revisions can be necessary in these patients, with a loss in function as well as in quality of life. The routine preoperative diagnostics include blood examination for C-reactive protein (CRP) and other biomarkers, as well as joint aspirate analysis for cell count, differentiation, and culture. Intraoperative specimens for histology and microbiology are also standard procedure. The microbiological examination of removed implants with sonication, in combination with the implementation of molecular biology techniques in microbiology, represent two novel techniques currently employed to enhance the differential diagnostics of PJI. We present here the step-wise procedure of analyzing joint aspirate and sonication fluid, using a cartridge-based multiplex polymerase chain reaction (PCR) system. Results were matched against conventional cultures and consensus criteria for PJI. Conventional microbiological cultures from tissue biopsies, joint aspirate and sonication fluid showed a sensitivity of 66.7%, 66.7%, and 88.9%, respectively, and a specificity of 82.3%, 54.6%, and 61.5%, respectively. The PCR diagnostic of the sonication fluid and the joint fluid showed a sensitivity of 50.0% and 55.6%, respectively, and both a specificity of 100.0%. Both PCR diagnostics combined had a sensitivity of 66.7% and a specificity of 100.0%. The multiplex PCR therefore presents a rapid diagnostic tool with moderate sensitivity but high specificity in diagnosing PJI.

Background and Objectives Knee osteoarthritis (OA) is a significant public health burden. Rates of total knee arthroplasty (TKA) in OA vary substantially between geographical regions, most likely due to the lack of standardised indication criteria. We set out to define indication criteria for the German healthcare system for TKA in patients with knee OA, on the basis of best evidence and transparent multi-stakeholder consensus. Methods We undertook a complex mixed methods study, including an iterative process of systematic appraisal of existing evidence, Delphi consensus methods and stakeholder conferences. We established a consensus panel representing key German national societies of healthcare providers (orthopaedic surgeons, rheumatologists, pain physicians, psychologists, physiotherapists), payers, and patient representatives. A priori defined consensus criteria were at least 70% agreement and less than 20% disagreement among the consensus panel. Agreement was sought for (1) core indication criteria defined as criteria that must be met to consider TKA in a normal patient with knee OA, (2) additional (not obligatory) indication criteria, (3) absolute contraindication criteria that generally prohibit TKA, and (4) risk factors that do not prohibit TKA, but usually do not lead to a recommendation for TKA. Results The following 5 core indication criteria were agreed within the panel: 1. intermittent (several times per week) or constant knee pain for at least 3 – 6 months; 2. radiological confirmation of structural knee damage (osteoarthritis, osteonecrosis); 3. inadequate response to conservative treatment, including pharmacological and non-pharmacological treatment for at least 3 – 6 months; 4. adverse impact of knee disease on patientʼs quality of life for at least 3 – 6 months; 5. patient-reported suffering/impairment due to knee disease. Additional indication criteria, contraindication criteria, and risk factors for adverse outcome were also agreed by a large majority within the multi-perspective stakeholder panel. Conclusion The defined indication criteria constitute a prerequisite for appropriate provision of TKA in patients with knee OA in Germany. In eligible patients, shared-decision making should eventually determine if TKA is performed or not. The next important steps are the implementation of the defined indication criteria, and the prospective investigation of predictors of success or failure of TKA in the context of routine care provision in Germany.

Antibiotic therapy is essential in foreign body associated infections. The treatment regime should aim at high tissue concentrations, high bioavailability, high biofilm penetration and good tolerance. We investigated whether the new cephalosporin ceftobiprole is active against clinical isolates from musculoskeletal foreign body associated infections. One hundred ninety-six staphylococci isolates (coagulase negative staphylococci and Staphylococcus aureus) derived from foreign body associated infections were tested towards susceptibility to ceftobiprole, using a test strip assay and broth microdilution. The MIC for all strains S. aureus indicated susceptibility to ceftobiprole. The MIC of only two strains of coagulase negative staphylococci was above 2 mg/L. Our results show that ceftobiprole might be considered as an off-label treatment option in foreign body associated infections.

Fragestellung: Der Einsatz von Kurzschaftprothesen gewinnt als geeignete Alternative zur konventionellen „stielverankernden“ Totalendoprothese beim jungen und aktiven Patienten in der Behandlung der Koxarthrose zunehmend an Bedeutung. Propagierte Vorteile des Verfahrens sind die knochen- und schenkelhalserhaltende Implantation bei nahezu physiologischer Krafteinleitung in das proximale Femur. In diesem Zusammenhang prasentieren wir erste klinische und nativradiologische Ergebnisse der AIDA®-Kurzschaftprothese im Rahmen einer Single-Surgeon-Studie. Methodik: Bei der Studie handelt es sich um eine prospektive, klinische Multicenterstudie. Die Studie wurde von der Ethikkommission genehmigt. Das dargestellte Patientenkollektiv entstammt einem an der Multicenterstudie beteiligten Studiencenter. Implantiert wurden von Februar 2009 bis Dezember 2013 72 AIDA®-Kurzschaftprothesen (Fa. Implantcast) bei 71 Patienten bei definierter Indikationsstellung bei Koxarthrose. Alle Operationen wurden von 1 Operateur durchgefuhrt („single surgeon study“). 51 Patienten mit 52 Prothesen (Lebensalter 61 ± 3,2 Jahre [min.–max. 46–68 Jahre]; 35 weiblich; 16 mannlich) mit einer Standzeit > 2 Jahre wurden klinisch und nativradiologisch ausgewertet. Die Patienten wurden pra- und postoperativ im Rahmen eines festgelegten Studienprotokolls klinisch und nativradiologisch untersucht. Ergebnisse: Die klinischen Nachuntersuchungsergebnisse zeigen deutlich verbesserte funktionelle Ergebnisse postoperativ. Der Harris-Hip-Score stieg signifikant von praoperativ 41,4 ± 4,5 auf postoperativ 96,8 ± 3,2 Punkte zum Zeitpunkt der letzten Zwischenauswertung. Der stationare Aufenthalt betrug im Mittelwert 9,1 ± 1,2 Tage. Die nativradiologische Nachuntersuchung zeigte in allen Fallen einen festen Sitz des Kurzschafts ohne Lockerung, Migration und Resorptionssaume. Operationsspezifische Komplikationen wurden nicht beobachtet. Postoperativ kam es zu einer periprothetischen Femurschaftfraktur (Revisionsrate 1,9 %). Hier erfolgte die komplikationslose Revision auf einen zementfreien Geradschaft. Schlussfolgerung: Die AIDA-Kurzschaftprothese stellt unter strenger Indikationsstellung ein vielversprechendes Verfahren zur operativen Behandlung der Koxarthrose dar. Die kurzfristigen klinischen Ergebnisse sind ermutigend, langfristige Ergebnisse gilt es abzuwarten.

Revision of failed total hip arthroplasty with severe acetabular bone loss represents a rare but challenging problem. Anatomic reconstruction with biological defect augmentation as solid bone transplants or cancellous bone restores bone stock while providing good component stability. The objective of this study was to present short- to mid-term results of revision total hip arthroplasty with a modular ring system in a consecutive series of patients with severe acetabular bone loss. We retrospectively reviewed 39 consecutive patients (39 hips) with severe acetabular bone loss (Paprosky type 3 A and 3 B) reconstructed with revision total hip arthroplasty using the cementless modular ring system MRS-Titan®. The MRS-Titan® consists of independent ring systems that are adapted modularly to the defect situation. Combined with acetabular defect reconstruction by using cancellous bone in impaction grafting technique, the MRS-Titan® system offers a cement-free revision system that enables defect-adapted customization to individual anatomic matters, bridging of the acetabular bone defect and reconstruction of the centre of rotation. Initial stability of the implant was obtained by screw fixation. Harris hip score and sequential radiographs were used to evaluate clinical and radiographic results. At an average follow up of 31 months (range 12–69 months) 33 of 39 (84.6 %) of the implants were considered radiographically stable without signs of acetabular migration of more than 2 mm in the horizontal or vertical direction, implant rotation or screw breakage. Complications included six implant failures (15 %). We recorded one aseptic loosening of the MRS prosthesis after 20 months. Five patients (12.8 %) had to undergo revision surgery because of periprosthetic joint infection. Two patients had a dislocation postoperatively. The mean Harris hip score improved from 27 ± 14 points preoperatively to 76 ± 15 points at the time of last follow up. By achieving stable implant fixation and providing potential for biological fixation, treatment of severe acetabular bone loss in revision total hip arthroplasty with the modular ring system MRS-Titan provides a durable solution with good clinical and radiographic results and allows us to accomplish major goals of reconstruction.

The accurate diagnosis of periprosthetic joint infection (PJI) relies on clinical investigation, laboratory parameters, radiological methods, sterile joint aspiration for synovial fluid leucocyte count and microbiological analysis and tissue sampling for histopathology. Due to the limits in specificity and sensitivity of these methods, molecular techniques and new biomarkers were introduced into the diagnostic procedure. Histological examination is related to the amount of neutrophils in the periprosthetic tissue in frozen sections and formalin-fixed paraffin embedded material (FFPE). However, the threshold of neutrophils per defined area of tissue among various studies is very inconsistent.We have applied matrix-assisted laser desorption ionisation time-of-flight imaging mass spectrometry (MALDI IMS) to a total of 32 periprosthetic tissue samples of patients with PJI to detect peptides associated with areas of neutrophil infiltration.Specific peaks associated with a high amount of neutrophils were detected. Of these m/z peaks, four could be assigned to predictive neutrophil molecules. These peptides include annexin A1, calgizzarin (S100A11), calgranulin C (S100A12) and histone H2A. By MALDI IMS, these peptides could be shown to be co-localised with the infiltration of neutrophils in the immediate vicinity of the periprosthetic interface, whereas more distant areas did not show neutrophil invasion or infection-related peptides.MALDI IMS is a new method allowing identification of neutrophil peptides in periprosthetic tissues and may be a surrogate for counting neutrophils as an objective parameter for PJI.

In den letzten Jahren wurden viele neue Heilverfahren fur muskuloskeletale Erkrankungen entwickelt. Einige dieser neuen Verfahren beruhen auf dem gezielten Einsatz von Stammzellen, um Heilungsprozesse zu initiieren, Defizite auszugleichen oder die Regeneration von Sehnen, Muskeln, Knochen oder Knorpel zu aktivieren. Dies kann durch den direkten Einsatz von Stammzellen auf oder in einem Tragermaterial oder durch eine Kombination mit Tissue Engineering erreicht werden. In diesem Artikel geben wir einen kurzen Uberblick uber mogliche Einsatzgebiete von induzierbaren pluripotenten, hamatopoetischen und adulten Stammzellen sowie uber deren Einsatz in muskuloskeletalem Gewebe. Zusatzlich fassen wir die derzeitige rechtliche Situation bei der Anwendung von Stammzellen am Menschen zusammen.

Deutschlandweit werden jahrlich 800 000 Frakturen versorgt. In ca. 10 % der Falle kommt es zur verzogerten Bruchheilung oder Pseudarthrosenbildung. Die operative Behandlung dieser Komplikationen ist aufwendig und mit erheblichen Kosten verbunden, daher kommt der nichtinvasiven Therapie ein zunehmendes Interesse zu. Die adjuvante Behandlung mittels Ultraschall wird bereits seit Jahren zur Verbesserung der Frakturheilung und zur Therapie der verzogerten Knochenheilung propagiert, aber ebenso kontrovers diskutiert. Diese Ubersichtsarbeit demonstriert den Stellenwert der niedrigintensiven, gepulsten Ultraschallbehandlung in der Frakturbehandlung anhand von Daten aus der Grundlagenforschung, tierexperimentellen Anwendungen und klinischen Studien.

The pre-operative differentiation between periprosthetic joint infection (PJI) and aseptic loosening after total hip (THA) or knee (TKA) arthroplasty is essential for successful therapy and relies in part on the use of molecular markers. The objective of this study was to assess serum levels of lipopolysaccharide-binding protein (LBP) as a diagnostic tool for PJI and to compare its accuracy with standard tests.One hundred and twenty patients presenting with a painful TKA or TKA with indication for surgical revision were included in this prospective, controlled, clinical trial at a single centre. Pre-operative blood and serum samples were collected and analysed for white blood cell (WBC) count, C-reactive protein (CRP) and LBP. The definite diagnosis of periprosthetic joint infection was determined on the basis of clinical, microbiological and histopathological examination.LBP showed significantly higher values in PJI compared with aseptic loosening (p 0.001) and control (p 0.001), with a specificity of 66% and a sensitivity of 71% at a cutoff value of7 ng/ml. In combination with CRP, the positive predictive value for PJI was at 0.67; negative predictive value with both negative was at 0.77.Patients with PJI have elevated serum levels of LBP when compared with patients with aseptic loosening. The use of LBP in serum appears not to be a more accurate marker than CRP level in serum for detecting PJI. On the basis of these results, we cannot recommend the sole use of LBP for differentiating PJI and aseptic loosening following THA and TKA.

Einleitung: Minimalinvasive Zugangswege zum Huftgelenk bei der primaren Endoprothetik stehen seit einigen Jahren im Fokus einer kontroversen Diskussion. Minimalinvasive Zugange versprechen eine weichteilschonende Implantation mit Vorteilen in den postoperativen funktionellen Ergebnissen und reduziertem intraoperativem Blutverlust. Methodik: Auf Grundlage einer umfassenden Literatursuche (Einschlusskriterien: Prospektiv randomisierte klinische Studien, systematische Reviews, Metaanalysen) wird die verfugbare Primar- und Sekundarliteratur beurteilt, Vor- und Nachteile minimalinvasiver Zugange zum Huftgelenk werden im Vergleich zu traditionellen Zugangen diskutiert. Ergebnisse: Die verfugbare Primar- und Sekundarliteratur belegt Vorteile minimalinvasiver Zugange zum Huftgelenk im funktionellen Outcome in der fruhen postoperativen Phase. Nach 1 Jahr postoperativ bestehen keine funktionellen Unterschiede mehr zum Standardzugang. Des Weiteren werden eine verminderte Operationsdauer, ein verminderter Blutverlust und ein kurzerer stationarer Aufenthalt belegt. Studien der Evidenzgrade I und II zu mittel- und langfristigen Ergebnissen minimalinvasiver Zugange im Vergleich zu den etablierten Standardzugangen sind nicht verfugbar. Die verfugbaren Systematic Reviews und Metaanalysen lassen lediglich eine globale Beurteilung der Primarliteratur zu minimalinvasiven Zugangswegen zu, ohne dabei zwischen den etablierten Standardzugangen und dem nach minimalinvasiven Kriterien modifizierten Pendant zu differenzieren. Es existieren zurzeit wenig bildmorphologische In-vivo-Hinweise (MRT) fur eine Reduktion des muskularen Traumas durch Verwendung von MIS-Zugangen. Fazit: Die verfugbare Literatur erlaubt derzeit kein abschliesendes Urteil zur Wertigkeit minimalinvasiver Zugangswege zum Huftgelenk. Weiterfuhrende prospektiv randomisierte kontrollierte Studien sind notwendig, um die sehr guten (Langzeit-)Ergebnisse der etablieren Standardzugange mit den nach minimalinvasiven Kriterien modifizierten Huftzugangen zu vergleichen. Solange keine ausreichenden Langzeitergebnisse zu Komplikations- und Revisionsraten minimalinvasiver Zugangswege vorliegen, konnen minimalinvasive Zugangswege nicht als Goldstandard empfohlen werden.

Primarstabile Uberbruckung azetabularer Knochendefekte vom Typ Paprosky IIa und IIb und Rekonstruktion des anatomischen Rotationszentrums. Begleitende Defektrekonstruktion mit homologer Spongiosa in „Impaction-Grafting“-Technik zur Wiederherstellung eines tragfahigen Implantatlagers und „down grading“ der knochernen Defektsituation im erneuten Revisionsfall. Azetabulare Defektsituationen des Pfannenbodens/-erkers bei verbliebener Resttragfahigkeit des Pfannenerkers bei intaktem kaudalem Pfannenrand (Paprosky-Typ IIa, IIb). Bestehender Huftgelenksinfekt. Azetabulare Knochendefekte oder eine nichttragfahige Knochensubstanz, die eine sichere Auflage des metallischen Abstutzrings in der Pfanneneingangsebene verhindern. Transglutealer, lateraler Huftgelenkzugang. Entfernung der gelockerten, azetabularen Prothesenkomponente. Auffrasen des Implantatlagers unter Erhalt des mechanisch stabilen Restknochens. Praparation der homologen Spongiosachips und Impaktierung in die azetabularen Knochendefekte. Einbringen der Pfannendachschale nach Verankerung des kaudalen Hakens in der Inscisura acetabuli. Primarstabile Verankerung mit Platzierung von 1–2 Domschrauben im Kraftvektorverlauf sowie Spongiosaschrauben im Pfannendachbereich. Einzementierung des Polyethyleninlays. Mobilisation an 2 Unterarmgehstutzen ab dem 1. postoperativen Tag. Teilbelastung mit 20 kg fur 6 Wochen postoperativ. Bei nativradiologisch unverandertem Implantatsitz Belastungssteigerung nach 6 Wochen um 10 kg/Woche bis zur Vollbelastung unter Fortfuhren der Thromboseprophylaxe. Limitation der Huftflexion auf 90°. Adduktionsvermeidung unter gleichzeitiger Ausenrotation in den ersten 6 postoperativen Wochen sowie von Freizeit- und Sportaktivitaten mit Sprung- und axialen Stosbelastungen fur 12 Monate postoperativ. Rontgenkontrollen nach 3, 6 und 12 Monaten und 2-jahrliche Verlaufskontrolle. Zwischen 2008 und 2011 wurden 22 konsekutive Patienten mit 23 Implantaten versorgt und uber 38 ± 11 Monate nachuntersucht. Pra- vs. postoperativ zeigte sich eine signifikante Steigerung im Harris-Hip-Score (82,2 ± 8,7 vs. 44,7 ± 10,7) und im Merle-d’Aubigne-Score (14,6 ± 1,9 vs. 7,5 ± 1,3). In 21 Fallen radiologischer Nachweis einer Osseointegration; 2 partielle Lysesaume (9 %) in den Zonen I–III nach DeLee und Charnley. Zunehmende trabekulare Zeichnung im Sinne einer Wiederherstellung der trabekularen Mikroarchitektur im augmentierten Areal zeigten 20 Abstutzschalen (87 %), eine stabile Integration bei unveranderter Positionierung des anatomischen Rotationszentrums 21 Abstutzschalen (92 %) und eine Implantatmigration 2 Implantate (9 %). Operative Revision im Follow-up bei 3 Prothesen (13 %).

Summary Despite reliable results of ankle fusion for advanced haemophilic arthropathy, total ankle replacement (TAR) may be functionally advantageous. There is only very limited literature data available on TAR in patients with haemophilia. The objective of this study is to evaluate the short- and mid-term results after TAR in patients with end-stage haemophilic ankle arthropathy and concomitant virus infections. In a retrospective study, results after eleven TAR in 10 patients with severe (n = 8) and moderate (n = 2) haemophilia (mean age: 49 ± 7 years, range, 37–59) were evaluated at a mean follow-up of 3.0 years (range, 1.2–5.4). Nine patients were positive for hepatitis C, five were HIV-positive. Range of motion (ROM), AOFAS-hindfoot-score, pain status (visual analogue scale, VAS) as well as patient satisfaction were evaluated. In two cases deep prosthesis infection occurred leading to the removal of the implant. In the remaining eight patients the mean AOFAS score improved significantly from 21.5 to 68.0 points (P

Current concepts in the treatment of prosthetic joint infections include prosthetic retention and exchange strategies according to published recommendations. A useful algorithm should fit for each type of prosthetic joint infection, even the most complicated situations. We present the outcome of 147 patients with prosthetic joint infections of the hip or the knee joint in an unselected population in clinical routine.Between November 2006 and November 2009, 147 consecutive patients with prosthetic joint infections of the hip or knee were treated according to an algorithm based on the concept published by Zimmerli et al. in 2004. Causative organism, duration of infection, patient comorbidities, surgical treatment, antibiotic treatment, and outcome of treatment were analysed retrospectively. According to the criteria duration of infection, stability of prosthesis, local and systemic risk factors, and susceptibility of the causative pathogen, patients were treated either with debridement and retention or a long-interval two-stage procedure.A pathogen could be detected in 82.8% of the patients, gram-positive cocci being most common. Twenty-seven patients were treated with debridement and retention and 120 were treated with a two-stage procedure. In 68 cases difficult-to-treat pathogens could be detected, a polymicrobial infection was found in 51 patients. Definitely free of infection were 71.6% after a two-stage procedure, and 70.4% after debridement and retention.Our data indicates that the applied algorithm is suitable to be applied as a day-to-day routine, and we confirmed that published results from the literature can be reproduced in an inhomogeneous patient cohort.

Ziel: Die vorliegende kontrollierte Pilotstudie versucht erstmals am Beispiel der primären Oberflächenersatzendoprothetik des Kniegelenks, die durch die operative Aus- und Weiterbildung an einem Ausbildungszentrum entstehenden Mehrkosten vor dem Hintergrund der DRG-Vergütung zu quantifizieren und diese einer gesundheitsökonomischen Kosten-Erlös-Analyse zu unterziehen. Methode: Anhand standardisierter Behandlungspfade wurden konsekutive Patienten der Implantation einer bikondylären Oberflächenersatzprothese des Kniegelenks unterzogen und durch einen Facharzt ≥ 1000 (Kategorie A) und ≥ 200 eigenverantwortlich durchgeführten Primärimplantationen (Kategorie B) im Vergleich zu einem Weiterbildungsassistenten (Kategorie C) ohne vorhergehende operative Erfahrung operiert (n = 30 Patienten pro Gruppe). Die evaluierten Einzelkollektive zeigten hinsichtlich Alter, Geschlecht, Gewicht, Körpergröße, BMI, ASA und PCCL präoperativ keine signifikanten Unterschiede. Kostenseitig wurden die Schnitt-Naht-Zeit, PCCL-relevante intra- und postoperative Komplikationen, die Gabe von Blutprodukten, die Tageskosten und die stationäre Verweildauer, erlösseitig die DRG, PCCL-Stufe sowie der CMI erfasst. Ergebnisse: Der Operateur der Kategorie C generiert Mehrkosten von 1111,7 ± 97 € vs. Kategorie A und 1729,8 ± 152 € vs. Kategorie B (p > 0,05). Diese resultierten aus einer verlängerten Schnitt-Naht-Zeit, einer erhöhten EK-Gabe, erhöhten Tageskosten sowie einem verlängerten stationären Aufenthalt. Durch eine erhöhte Rate PCCL-relevanter Komplikationen, der Eingruppierung in eine finanziell ertragsreichere DRG sowie einem erhöhten CMI summierten sich die Mehrerlöse des Operateurs der Kategorie C auf 474,78 ± 82 € vs. Kategorie A und 150,54 ± 52 € vs. Kategorie B (p 0,05). Fazit: Operative Ausbildung kostet Geld. Hieraus resultiert die Forderung der aus- und weiterbildenden Kliniken, zur sachgerechten Finanzierung der Mehraufwendungen aus operativer Weiterbildung einen finanziellen Ausgleich gegenüber Häusern zu erhalten, die keinen Anteil an der ärztlichen Weiterbildung leisten, aber von extern aus- und weitergebildeten (Fach-) Ärzten profitieren.

The purpose of this study was to analyze the different causes of symptomatic osteoarthritis (OA) of the hip joint in active duty soldiers requiring a total hip arthroplasty and the hypothesis that soldiers had a reduced prevalence of secondary OA as a result of a selection process that has taken place through multiple medical assessments during their military career. We analyzed patient records from 2006 to 2012 for male patients ≤60 years with OA of the hip and indication for total hip arthroplasty in a military hospital in which civilian patients are also treated. About 44 military patients (MP) and 69 civilian patients (CP) were included. The prevalence of different causes of OA of the hip did not differ significantly in both groups (primary OA MP: 59.1% [n = 26], CP: 56.5% [n = 39]; dysplasia MP: 25.0% [n = 11], CP: 24.6% [n = 17]; femoral head necrosis MP: 11.4% [n = 5], CP: 13% [n = 9]; post-traumatic OA MP: 4.5% [n = 2], CP: 5.8% [n = 4]). In conclusion, recurrent medical assessments that are usually based alone on clinical examinations were not able to reduce the prevalence of prearthrotic deformities as a joint-specific risk factor for the development of symptomatic hip OA in our military collective.

Bone resection regarding adequate surgical margins is the treatment of choice for malignant bone tumors. In the case of metastasis-related complications, so-called skeletal-related events, it is highly important to achieve pain relief and a stable joint situation to re-mobilize the patients immediately following surgery. To bridge the often large osseous defect zones after tumor resection, both cemented and uncemented modular endoprosthetic systems are widely used. Patients undergoing tumor-related endoprosthetic orthopedic surgery are facing high risk for developing a periprosthetic joint infection (PJI). The immunocompromised condition due to anti-neoplastic treatment and long operation time with large exposure of tissue contributes to a high risk of infection.The authors present a case series of 100 patients (31% primary bone tumor and 69% metastasis-related surgery) undergoing tumor-related lower limb salvage surgery with special regard to periprosthetic joint infection and the management of this "difficult to treat" situation. Furthermore, a review of the current literature regarding infection following bone tumor resection and endoprosthetic reconstruction is performed and discussed.The median follow-up was 24 months (range 12-108 months). Ten patients (10%) suffered from a periprosthetic joint infection. We recorded six acute infections (type I)4 weeks after surgery, one infection4 weeks after surgery (type II), and three late infections (type III). According to the definition of Laffer et al., three of our patients (30%) are probably free of infection, one patient died of PJI-associated sepsis, and five patients were free of infection, but without restoration of the affected joint.In conclusion, our own results show that perimegaprosthetic joint infection among silver-coated implants, in patients undergoing tumor-related surgery of the lower limb, is lower compared to non-silver-coated implants. Due to heterogeneity of patients and potential treatment options, the treatment regime should be tailored for the patients' individual situation.

Different dissection studies as well as comparative studies about the anterolateral ligament of the knee (ALL) already exist and the structure’s topology and properties have been shown. However, most of the studies investigating the ligament were performed in embalmed knees, which is thought to change the structural integrity of ligaments and thus the topologic and dynamic measurements. Since the biomechanical function of the ALL is not fully understood until today and a correlation with the pivot shift phenomenon is yet speculative, further studies will have to clarify its definitive importance. Its function as a limiter of internal rotation and lateral meniscal extrusion leads to the assumption of a secondary knee stabilizer. Twenty paired fresh-frozen cadaveric knees of ten donors have been dissected in a layerwise fashion. After identification of the ALL, topologic measurements were undertaken using a digital caliper. The ALL could be identified as a tender, pearly structure in front of the anterolateral joint capsule in only 60% of the dissected knee joints. Only 20% of donors had a bilateral ALL while 80% had an ALL only in one side. Mean length, thickness and width as well as topographic measurements were comparable to other available studies investigating fresh-frozen cadavers. Anatomy and topography of the ALL seem to be highly variable, but consistent within certain borders. Prevalence has to be argued though as it strongly differs between studies. The impact of an ALL absence, even if only unilateral, needs to be investigated in clinical and imaging studies to finally clarify its importance.

Prosthetic joint infections are a major challenge in total joint arthroplasty, especially in times of accumulating drug resistancies. Even though predictive risk classifications are a widely accepted tool to define a suitable treatment protocol a classification is still missing considering the difficulty in treating the -causative pathogen antibiotically. In this study, we present and evaluate a new predictive risk stratification for prosthetic joint infections in 120 cases, treated with a two-stage exchange. Treatment outcomes in 120 patients with proven prosthetic joint infections in hip and knee prostheses were regressed on time of infection, systemic risk factors, local risk factors and the difficulty in treating the causing pathogen. The main outcome variable was "definitely free of infection" after two years as published. Age, gender, and BMI were included as covariables and analyzed in a logistic regression model. 66 male and 54 female patients, with a mean age at surgery of 68.3 years±12.0 and a mean BMI of 26.05±6.21 were included in our survey and followed for 29.0±11.3 months. We found a significant association (p0.001) between our score and the outcome parameters evaluated. Age, gender and BMI did not show a significant association with the outcome. These results show that our score is an independent and reliable predictor for the cure rate in prosthetic joint infections in hip and knee prostheses treated within a two-stage exchange protocol. Our score illustrates, that there is a statistically significant, sizable decrease in cure rate with an increase in score. In patients with prosthetic joint infections the validation of a risk score may help to identify patients with local and systemic risk factors or with infectious organisms identified as "difficult to treat" prior to the treatment or the decision about the treatment concept. Thus, appropriate extra care should be considered and provided.

Rheumatoid arthritis (RA) is a chronic autoimmune disease with a heterogeneous clinical presentation affecting about 1 % of adults in developed countries. Currently, the diagnosis is based on the revised criteria of the American College of Rheumatology (ACR) and the European League Against Rheumatism (EULAR) from 2010. These criteria include clinical and laboratory parameters. Because of the variability of the clinical picture, delayed diagnosis of RA occurs in a significant subset of patients. Therefore, the discovery of novel biomarkers that improve the diagnosis of RA is of particular interest. Recently, it became evident that miRNAs have regulatory activities in physiologic processes and human diseases. Upregulation of miR-146a, miR-155, and miR-223 has been shown in various compartments such as serum, blood, synovial fluid, and tissues in patients with RA. A total of 87 samples were analyzed (RA 50, osteoarthritis (OA) 37). RNA was isolated from formalin-fixed paraffin-embedded synovial tissue (FFPE). The relative expression of miR-146a, miR-155, and miR-223 was determined by comparison to a housekeeping RNA molecule (snRNA U6) and an RNA pool from histologically and clinically verified OA samples. miR-146a, miR-155, and miR-223 were significantly elevated in RA compared to OA synovial tissues (p

Osteoarthritis is a common and progressive joint disorder. Despite its widespread, in clinical practice only late phases of osteoarthritis that are characterized by severe joint damage are routinely detected. Since osteoarthritis cannot be cured but relatively well managed, an early diagnosis and thereby early onset of disease management would lower the burden of osteoarthritis. Here we evaluated if biophysical parameters of small synovial fluid samples extracted by single molecule microscopy can be linked to joint damage. In healthy synovial fluid (ICRS-score 2/s, N = 5) than in samples from patients with joint damage (ICRS-score > 2) (4.5 μm2/s, N = 16). More strikingly, the diffusion coefficient of hyaluronan in healthy synovial fluid was on average 30% slower than expected by sample viscosity. This effect was diminished or missing in samples from patients with joint damage. Since single molecule microscopy needs only microliters of synovial fluid to extract the viscosity and the specific diffusion coefficient of hyaluronan this method could be of use as diagnostic tool for osteoarthritis.

Purpose To compare complication rates and outcome of open lateral retinacular (LR) lengthening and open LR release in the treatment of lateral patellar hypercompression syndrome (LPHS). Methods In a prospective double-blinded study, 28 patients (mean age, 48 years; 21 women and 7 men) received either LR release (14 patients) or LR lengthening (14 patients) in alternating fashion over the same lateral parapatellar skin incision for LPHS (blinding of patients to surgical procedure [i.e., single blinding]). Strict inclusion criteria (retinacular pain, tight retinaculum, decreased patellar mobility) were used to exclude other reasons for anterior knee pain (patellar instability, leg malalignment or maltorsion, trochlear dysplasia, patella alta). The surgeon and postsurgical rehabilitation were the same. Preoperatively and at 3, 6, 12, and 24 months postoperatively, complications, muscle atrophy, and Kujala patellofemoral outcome score were documented by examiners blinded to the surgical procedure (double blinding). All patients completed 2 years of follow-up. Results The results of 2 years of follow-up showed that recurrence of LPHS, as indicated by the patellar tilt test and decreased medial patellar glide test, developed in 2 cases after LR release and 1 case after LR lengthening ( P > .999). Medial patellar subluxation, as indicated by the gravitation-subluxation test and increased medial patellar glide test, developed in 5 cases after LR release and no case after LR lengthening ( P = .041). Quadriceps atrophy, as indicated by the mean circumference difference compared with the healthy contralateral side, was significantly higher ( P = .001) in the LR release group (1.8 cm) than in the LR lengthening group (0.2 cm). The mean Kujala score was significantly lower ( P = .035) in the LR release group (77.2 points) than in the LR lengthening group (88.4 points). Conclusions In this prospective double-blinded study, retinacular lengthening showed less medial instability, less quadriceps atrophy, and a better clinical outcome at 2 years compared with retinacular release. We believe that this may be explained by the controlled preservation of the lateral patellar muscle-capsuloligamentous continuity after retinacular lengthening. Level of Evidence Level II, prospective double-blinded comparative study.