André Busch

Zusammenfassung Die Schenkelhalsfraktur (SHF) ist die häufigste Fraktur des älteren Menschen und auch durch ein hohes Mortalitätsrisiko von hoher sozioökonomischer Bedeutung. Die Diagnostik erfolgt durch die klinische Untersuchung und bildgebende Verfahren. Die im klinischen Alltag verwendeten Klassifikationssysteme orientieren sich an der Prognose und sind somit eine wertvolle Entscheidungshilfe für die Wahl des Therapieverfahrens. Entscheidend für den Therapieerfolg ist die zeitnahe operative Versorgung. Während ältere Patienten (> 60 Jahre) bei arthrotisch vorgeschädigtem Gelenk und höherem Frakturdislokationsgrad von einem frühzeitigen Gelenkersatz profitieren (biopolare Systeme, Totalendoprothese, Dual-Mobility-Systeme), sollte bei Jüngeren und geringem Dislokationsgrad der Hüftgelenkerhalt durch Osteosynthese angestrebt werden. Die vorliegende Arbeit fasst die klinisch relevanten Aspekte zur SHF zusammen und gibt unter Hinzuziehung der wissenschaftlichen Literatur einen Überblick über die aktuellen Therapieverfahren.

Zusammenfassung Hintergrund Proximale Humeruskopffrakturen spielen im klinischen Alltag und in der Alterstraumatologie aufgrund ihrer hohen Inzidenz eine große Rolle, wobei die posttraumatische Humeruskopfnekrose bei gelenkerhaltender Therapie eine häufig beobachtete Langzeitkomplikation ist. Fragestellung In der vorliegenden Arbeit werden Daten zur Epidemiologie und Kausalität der Humeruskopfnekrose übersichtlich dargestellt. Eine große Bedeutung kommt hierbei der Anatomie, der Frakturform und assoziierten Risikofaktoren zu. Material und Methoden Es erfolgt eine Aufarbeitung der aktuellen Literatur zum Thema und die kritische Darstellung der Therapieoptionen. Ergebnisse Humeruskopffrakturen sind die siebthäufigste Fraktur des Menschen. Trotz moderner Implantate und Operationstechniken liegt die Komplikationsrate weiterhin bei bis zu 40 %. Innerhalb der fehlgeschlagenen Behandlungen stellt die posttraumatische Nekroserate mit 34 % eine der häufigsten Komplikationen dar und führt zu Revisionsraten von bis zu 19 %. Fazit Bei der Therapie der Humeruskopffraktur müssen zahlreiche Variablen berücksichtigt werden. Hierbei gilt es, die individuelle Frakturform und individuelle Faktoren mit in die Wahl des Osteosyntheseverfahrens einzubeziehen. Nach Daten der aktuellen wissenschaftlichen Literatur sollten insbesondere moderne winkelstabile Implantate verwendet werden und stets der endoprothetische Gelenkersatz kritisch abgewägt werden. Hierbei spielt die Erwartungshaltung des Patienten an das postoperative Aktivitätsniveau eine große Rolle.

Background: In the past, radiographic imaging was of minor relevance in the diagnosis of periprosthetic joint infections (PJI). Since metal artefact reduction sequences (MARS) are available, magnetic resonance imaging (MRI) has become a promising diagnostic tool for the evaluation of hip arthroplasty implants. The purpose of the present study was to evaluate the efficacy of MARS-MRI in comparison to established diagnostic tools to distinguish between aseptic failure and PJI. Methods: From July 2018 to September 2019, 33 patients classified as having an aseptic joint effusion were recruited into the study. The group included 22 women and 11 men with a mean age of 70.4 ± 13.7 (42–88) years. In the same period, 12 patients were classified as having a PJI. The group consisted of 9 women and 3 men with a mean age of 72.5 ± 10.6 (54–88) years. MARS-MRI was conducted using the optimized parameters at 1.5 T in a coronal and axial STIR (short-tau-inversion recovery), a non-fat-saturated T2 in coronal view and a non-fat-saturated T1 in transverse view in 45 patients with painful hip after total hip arthroplasty (THA). Normally distributed continuous data were shown as mean ± standard deviation (SD) and compared using student's t-test. Non-normally distributed continuous data were shown as mean and compared using the Mann–Whitney U test. Results: Synovial layering and muscle edema were significant features of periprosthetic joint infection, with sensitivities of 100% and specifities of 63.0—75.0%. The combined specifity and sensitivity levels of synovial layering and muscular edema was 88.0% and 90.0%. Granulomatous synovitis was a significant feature for aseptic failure, with 90.0% sensitivity and 57.0% specifity. Conclusion: MARS-MRI is as suitable as standard diagnostic tools to distinguish between aseptic failure and PJI in patients with THA. Further studies with larger patient numbers have to prove whether MARS-MRI could be integral part of PJI diagnostic.

Titanium implants are frequently applied to the bone in orthopedic and trauma surgery. Although these biomaterials are characterized by excellent implant survivorship and clinical outcomes, there are almost no data available on the initial protein layer binding to the implant surface in situ. This study aims to investigate the composition of the initial protein layer on endoprosthetic surfaces as a key initiating step in osseointegration. In patients qualified for total hip arthroplasty, the implants are inserted into the femoral canal, fixed and subsequently explanted after 2 and 5 min. The proteins adsorbed to the surface (the implant proteome) are analyzed by liquid chromatography–tandem mass spectrometry (LC-MS/MS). A statistical analysis of the proteins’ alteration with longer incubation times reveals a slight change in their abundance according to the Vroman effect. The pathways involved in the extracellular matrix organization of bone, sterile inflammation and the beginning of an immunogenic response governed by neutrophils are significantly enriched based on the analysis of the implant proteome. Those are generally not changed with longer incubation times. In summary, proteins relevant for osseointegration are already adsorbed within 2 min in situ. A deeper understanding of the in situ protein–implant interactions in patients may contribute to optimizing implant surfaces in orthopedic and trauma surgery.

Background:In the past, radiographic imaging was of minor relevance in the diagnosis of periprosthetic joint infections (PJI). Since metal artefact reduction sequences (MARS) are available, magnetic resonance imaging (MRI) has become a promising diagnostic tool for the evaluation of hip arthroplasty implants. The purpose of the present study was to evaluate the efficacy of MARS MRI in comparison to established diagnostic tools to distinguish between aseptic failure and PJI.Methods:Between July 2018 to September 2019, MARS-MRI was conducted using the optimized parameters at 1.5 T in a coronal and axial STIR (short-tau-inversion recovery), a non-fat-saturated T2 in coronal view and a non-fat-saturated T1 in transverse view in 45 patients with painful hip after THA.Results:Synovial layering and muscle edema were significant features of periprosthetic joint infection, with sensitivities of 100% and specifities of 63.0 - 75.0%. The combined specifity and sensitivity levels of synovial layering and muscular edema was 88.0% and 90.0%. Granulomatous synovitis was a significant feature for aseptic failure, with 90.0% sensitivity and 57.0% specifity.Conclusion:MARS-MRI is as suitable as standard diagnostic tools to distinguish between aseptic failure and PJI in patients with a total hip arthroplasty (TJA). Further studies with larger patient numbers have to prove whether MARS-MRI could be integral part of PJI diagnostic.

Zusammenfassung Die Organisation eines effektiven und effizienten Wissenstransfers ist eine große Herausforderung moderner Fachkommunikation. Durch die Aufbereitung von Begriffen und Begriffsbeziehungen in Begriffssystemen und deren übersichtliche und verständliche Visualisierung in einer Concept-Map macht das Terminologiemanagement Wissen einfach und schnell verfügbar. So kann es effizienter für die Fachkommunikation genutzt werden.

Background Progressive oxidation of highly cross-linked ultra-high molecular weight (UHMPWE-X) liners is considered to be a risk factor for material failure in THA. Antioxidants such as vitamin E (alpha-tocopherol) (UHMWPE-XE) were supplemented into the latest generation of polyethylene liners. To prevent inhomogenous vitamin E distribution within the polymer, blending was established as an alternative manufacturing process to diffusion. The purpose of the present study was to investigate the in vivo wear behavior of UHMWPE-XE in comparison with conventional UHMWPE-X liners using virtual CAD-based radiographs. Methods Until now, 94 patients from a prospective, randomized, controlled, multicenter study were reviewed at 5-year follow-up. Of these, 51 (54%) received UHMWPE-XE and 43 (46%) UHMWPE-X liners. Anteroposterior pelvic radiographs were made immediately after surgery and at 1 and 5 years postoperatively. The radiographs were analyzed using the observer-independent analysis software RayMatch^® (Raylytic GmbH, Leipzig, Germany). Results The mean wear rate was measured to be 23.6 μm/year (SD 13.7; range 0.7–71.8 μm). There were no significant differences between the two cohorts (UHMWPE-X: 23.2 μm/year vs. UHMWPE-XE: 24.0 μm/year, p = 0.73). Cup anteversion significantly changed within the 1st year after implantation independent from the type of polyethylene liner [UHMWPE-X: 18.2–23.9° (p = 0.0001); UHMWPE-XE: 21.0–25.5° (p = 0.002)]. No further significant changes of cup anteversion in both groups were found between year 1 and 5 after implantation [UHMWPE-X (p = 0.46); UHMWPE-XE (p = 0.56)]. Conclusion The present study demonstrates that the addition of vitamin E does not adversely affect the midterm wear behavior of UHMWPE-X. The antioxidative benefit of vitamin E is expected to become evident in long-term follow-up. Cup anteversion increment by 5° within the 1st year is likely a result of the released hip flexion contracture resulting in an enhanced posterior pelvic tilt. Therefore, a reassessment of target values in acetabular cup placement might be considered.

Bone replacement materials have been successfully supplied for a long time. But there are cases, especially in critical sized bone defects, in which the therapy is not sufficient. Nowadays, there are multiple bone substitutes available. Autologous bone grafts remain the “gold standard” in bone regeneration. Yet, donor-site morbidity and the available amount of sufficient material are limitations for autologous bone grafting. This study aimed to provide information about the current status in research regarding bone substitutes. We report on the advantages and drawbacks of several bone substitutes. At the end, we discuss the current developments of combining ceramic substitutes with osteoinductive substances.