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The AMADEUS score is not a sufficient predictor for functional outcome after high tibial osteotomy
(2023)
Purpose
The Area Measurement And Depth Underlying Structures (AMADEUS) classification system has been proposed as a valuable tool for magnetic resonance (MR)-based grading of preoperatively encountered chondral defects of the knee joint. However, the potential relationship of this novel score with clinical data was yet to determine. It was the primary intention of this study to assess the correlative relationship of the AMADEUS with patient reported outcome scores in patients undergoing medial open-wedge high tibial valgus osteotomy (HTO). Furthermore, the arthroscopic ICRS (International Cartilage Repair Society) grade evaluation was tested for correlation with the AMADEUS classification system.
Methods
This retrospective, monocentric study found a total of 70 individuals that were indicated for HTO due to degenerative chondral defects of the medial compartment between 2008 and 2019. A preoperative MR image as well as a pre-osteotomy diagnostic arthroscopy for ICRS grade evaluation was mandatory for all patients. The Knee Osteoarthritis Outcome Score (KOOS) including its five subscale scores (KOOS-ADL, KOOS-QOL, KOOS-Sports, KOOS-Pain, KOOS-Symptoms) was obtained preoperatively and at a mean follow-up of 41.2 ± 26.3 months. Preoperative chondral defects were evaluated using the AMADEUS classification system and the final AMADEUS scores were correlated with the pre- and postoperative KOOS subscale sores. Furthermore, arthroscopic ICRS defect severity was correlated with the AMADEUS classification system.
Results
There was a statistically significant correlation between the AMADEUS BME (bone marrow edema) subscore and the KOOS Symptoms subscore at the preoperative visit (r = 0.25, p = 0.04). No statistically significant monotonic association between the AMADEUS total score and the AMADEUS grade with pre- and postoperative KOOS subscale scores were found. Intraoperatively obtained ICRS grade did reveal a moderate correlative relation with the AMADEUS total score and the AMADEUS grade (r = 0.28, p = 0.02).
Conclusions
The novel AMADEUS classification system largely lacks correlative capacity with patient reported outcome measures in patients undergoing HTO. The MR tomographic appearance of bone marrow edema is the only parameter predictive of the clinical outcome at the preoperative visit.
The treatment landscape in multiple myeloma (MM) is shifting from genotoxic drugs to immunotherapies. Monoclonal antibodies, immunoconjugates, T-cell engaging antibodies and CART cells have been incorporated into routine treatment algorithms, resulting in improved response rates. Nevertheless, patients continue to relapse and the underlying mechanisms of resistance remain poorly understood. While Impaired death receptor signaling has been reported to mediate resistance to CART in acute lymphoblastic leukemia, this mechanism yet remains to be elucidated in context of novel immunotherapies for MM. Here, we describe impaired death receptor signaling as a novel mechanism of resistance to T-cell mediated immunotherapies in MM. This resistance seems exclusive to novel immunotherapies while sensitivity to conventional anti-tumor therapies being preserved in vitro. As a proof of concept, we present a confirmatory clinical case indicating that the FADD/BID axis is required for meaningful responses to novel immunotherapies thus we report impaired death receptor signaling as a novel resistance mechanism to T-cell mediated immunotherapy in MM.
Purpose
Hypertrophic cartilage is an important characteristic of osteoarthritis and can often be found in patients suffering from osteoarthritis. Although the exact pathomechanism remains poorly understood, hypertrophic de-differentiation of chondrocytes also poses a major challenge in the cell-based repair of hyaline cartilage using mesenchymal stromal cells (MSCs). While different members of the transforming growth factor beta (TGF-β) family have been shown to promote chondrogenesis in MSCs, the transition into a hypertrophic phenotype remains a problem. To further examine this topic we compared the effects of the transcription growth and differentiation factor 5 (GDF-5) and the mutant R57A on in vitro chondrogenesis in MSCs.
Methods
Bone marrow-derived MSCs (BMSCs) were placed in pellet culture and in-cubated in chondrogenic differentiation medium containing R57A, GDF-5 and TGF-ß1 for 21 days. Chondrogenesis was examined histologically, immunohistochemically, through biochemical assays and by RT-qPCR regarding the expression of chondrogenic marker genes.
Results
Treatment of BMSCs with R57A led to a dose dependent induction of chondrogenesis in BMSCs. Biochemical assays also showed an elevated glycosaminoglycan (GAG) content and expression of chondrogenic marker genes in corresponding pellets. While treatment with R57A led to superior chondrogenic differentiation compared to treatment with the GDF-5 wild type and similar levels compared to incubation with TGF-ß1, levels of chondrogenic hypertrophy were lower after induction with R57A and the GDF-5 wild type.
Conclusions
R57A is a stronger inducer of chondrogenesis in BMSCs than the GDF-5 wild type while leading to lower levels of chondrogenic hypertrophy in comparison with TGF-ß1.
Ultra-high-resolution photon-counting detector CT arthrography of the ankle: a feasibility study
(2023)
This study was designed to investigate the image quality of ultra-high-resolution ankle arthrography employing a photon-counting detector CT. Bilateral arthrograms were acquired in four cadaveric specimens with full-dose (10 mGy) and low-dose (3 mGy) scan protocols. Three convolution kernels with different spatial frequencies were utilized for image reconstruction (ρ\(_{50}\); Br98: 39.0, Br84: 22.6, Br76: 16.5 lp/cm). Seven radiologists subjectively assessed the image quality regarding the depiction of bone, hyaline cartilage, and ligaments. An additional quantitative assessment comprised the measurement of noise and the computation of contrast-to-noise ratios (CNR). While an optimal depiction of bone tissue was achieved with the ultra-sharp Br98 kernel (S ≤ 0.043), the visualization of cartilage improved with lower modulation transfer functions at each dose level (p ≤ 0.014). The interrater reliability ranged from good to excellent for all assessed tissues (intraclass correlation coefficient ≥ 0.805). The noise levels in subcutaneous fat decreased with reduced spatial frequency (p < 0.001). Notably, the low-dose Br76 matched the CNR of the full-dose Br84 (p 0.999) and superseded Br98 (p < 0.001) in all tissues. Based on the reported results, a photon-counting detector CT arthrography of the ankle with an ultra-high-resolution collimation offers stellar image quality and tissue assessability, improving the evaluation of miniscule anatomical structures. While bone depiction was superior in combination with an ultra-sharp convolution kernel, soft tissue evaluation benefited from employing a lower spatial frequency.
Der adenovirale SOX9-Gentransfer induziert nach 3-wöchiger in vitro Pelletkultur die chondrogene Differenzierung humaner mesenchymaler Stammzellen in Pelletkultur wirksamer als der TGFB1 Gentransfer mit geringerer Chondrozytenhypertrophie. Eine solche Technologie könnte zukünftig in vivo die Bildung von stabilerem hyalinem Knorpelregeneratgewebe ermöglichen.
Patienten mit monoklonaler Gammopathie unklarer Signifikanz haben ein erhöhtes Risiko an einer Osteoporose, Knochenbrüchen oder einer reduzierten Leistungsfähigkeit zu leiden. Bisher hat sich noch keine Therapie zur Prävention dieser Komplikationen etabliert. Das Ziel unserer Studie war es, WBV als eine mögliche Trainingsmethode zu prüfen und den Einfluss auf die Fitness, Alltagsaktivität und Lebensqualität von Patienten mit monoklonaler Gammopathie zu untersuchen. Hierfür haben 15 Probanden mit MGUS/SMM ein Trainingsprogramm über 3 bzw. 6 Monate mit zwei Trainingseinheiten pro Woche für jeweils 30 Minuten absolviert. Die körperliche Leistungsfähigkeit wurde anhand verschiedener Funktionstests sowie der Erhebung von Körpermaßen betrachtet. Die Alltagsaktivität wurde mittels Fitnesstrackern untersucht. Anhand von 3 verschiedenen Fragebögen wurde zudem der Einfluss auf die Lebensqualität der Probanden durch das Training ermittelt. Zusammenfassend zeigte sich eine deutliche Verbesserung der Fitness und Ausdauer der Probanden, die Alltagsaktivität und die Lebensqualität wurden nicht durch das Vibrationstraining beeinflusst.
This work developed during the first funding period of the subproject B05 in the framework of the interdisciplinary research consortium TRR 225 ‘From the Fundamentals of Biofabrication toward functional Tissue Models’ and was part of a cooperation between the Orthopedic Department represented by Prof. Dr. Regina Ebert and the Institute of Organic Chemistry represented by Prof. Dr. Jürgen Seibel.
This project dealed with cellular behavior during the bioprinting process and how to influence it by modifying the cell glycocalyx with functional target molecules. The focus was on the impact of potential shear stress, that cells experience when they get processed in thermoresponsive bioinks, and a way to increase the cell stiffness via metabolic glycoengineering to attenuate shear forces. For the characterization of the metabolic glycoengineering, four different peracetylated and four non-acetylated modified monosaccharides (two mannose and two sialic acid sugars) were tested in primary human mesenchymal stromal cells (hMSC) and telomerase-immortalized hMSC (hMSC-TERT). Viability results demonstrated a dose-dependent correlation for all sugars, at which hMSC-TERT seemed to be more susceptible leading to lower viability rates. The assessment of the incorporation efficiencies was performed by click chemistry using fluorescent dyes and revealed also a dose-dependent correlation for all mannose and sialic acid sugars, while glucose and galactose variants were not detected in the glycocalyx. However, incorporation efficiencies were highest when using mannose sugars in the primary hMSC. A subsequent analysis of the temporal retention of the incorporated monosaccharides showed a constant declining fluorescence signal up to 6 d for azido mannose in hMSC-TERT, whereas no signal could be detected for alkyne mannose after 2 d. Investigation of the differentiation potential and expression of different target genes revealed no impairment after incubation with mannose sugars, indicating a normal phenotype for hMSC-TERT. Following the successful establishment of the method, either a coumarin derivative or an artificial galectin 1 ligand were incorporated into the cell glycocalyx of hMSC-TERT as functional target molecule. The biophysical analysis via shear flow deformation cytometry revealed a slightly increased cell stiffness and lowered fluidity for both molecules. A further part of this project aimed to control lectin-mediated cell adhesion by artificial galectin 1 ligands. As that hypothesis was settled in the work group of Prof. Dr. Jürgen Seibel, this work supported with an initial characterization of galectin 1 as part of the hMSC biology. A stable galectin 1 expression at gene and protein level in both hMSC and hMSC-TERT could be confirmed, at which immunocytochemical stainings could detect the protein only in the glycocalyx. The treatment of hMSC-TERT with a galectin 1 ligand in different concentrations did not show an altered gene expression of galectin 1. However, these first data in addition to the investigation of stiffness confirmed the applicability of specific and artificial
IV
galectin 1 ligands in biofabrication approaches to alter cell properties of hMSC. To conclude, metabolic glycoengineering has been successfully implemented in hMSC and hMSC-TERT to introduce glycocalyx modifications which reside there for several days. A proof of concept was carried out by the increase of cell stiffness and fluidity by the incorporation of a coumarin derivative or an artificial galectin 1 ligand.
For the characterization of shear stress impact on cells after printing in thermoresponsive bioinks, the processing of hMSC-TERT (mixing or additionally printing) with Pluronic F127 or Polyoxazoline-Polyoxazine (POx-POzi) polymer solution was investigated. While there were no changes in viability when using POx-POzi bioink, processing with Pluronic F127 indicated slightly lower viability and increased apoptosis activity. Assessment of cellular responses to potential shear stress showed no reorganization of the cytoskeleton independent of the bioink, but highly increased expression of the mechanoresponsive proto-oncogene c Fos which was more pronounced when using Pluronic F127 and just mixed with the bioinks. Interestingly, processing of the mechanoresponsive reporter cell line hMSC-TERT-AP1 revealed slightly elevated mechanotransduction activity when using POx-POzi polymer and just mixed with the bioinks as well. In conclusion, hMSC-TERT embedded in thermoresponsive bioinks might shortly experience shear stress during the printing process, but that did not lead to remarkable cell damage likely due to the rheological properties of the bioinks. Furthermore, the printing experiments also suggested that cells do not sense more shear stress when additionally printed.
Purpose
To compare the performance of the dominant and nondominant hand during fundamental arthroscopic simulator training.
Methods
Surgical trainees who participated in a 2-day simulator training course between 2021 and 2023 were classified, according to their arthroscopic experience in beginners and competents. Only right-handed individuals with complete data sets were included in the study. Ambidexterity was trained using a box trainer (Fundamentals of Arthroscopic Surgery Training, Virtamed AG, Schlieren, Switzerland).Two tasks, periscoping for learning camera guidance and triangulation for additional instrument handling, were performed 4 times with the camera in the dominant hand and then in the nondominant hand. For each task, exercise time, camera path length, and instrument path length were recorded and analyzed.
Results
Out of 94 participants 74 right-handed individuals (22 females, 52 males) were classified to novices (n = 43, less than 10 independently performed arthroscopies) and competents (n = 31, more than 10 independently performed arthroscopies). Competents performed significantly better than novices. No significant difference was found after changing the guiding hand for the camera from the dominant to the nondominant hand regarding the camera path length and the instrument path length. Notably, tasks were performed even faster when using the camera in the nondominant hand.
Conclusions
Our data demonstrate that the learned manual skills during basic arthroscopic training are quickly transferred to the contralateral side. In consequence, additional fundamental skills training for camera guidance and instrument handling of the nondominant hand are not necessary.
Clinical Relevance
For skillful arthroscopy, camera guidance and instrument handing must be equally mastered with both hands. It is important to understand how hand dominance may affect learning during arthroscopic simulator training.
Self-assembling three-dimensional organoids that do not rely on an exogenous scaffold but maintain their native cell-to-cell and cell-to-matrix interactions represent a promising model in the field of tendon tissue engineering. We have identified dermal fibroblasts (DFs) as a potential cell type for generating functional tendon-like tissue. The glucocorticoid dexamethasone (DEX) has been shown to regulate cell proliferation and facilitate differentiation towards other mesenchymal lineages. Therefore, we hypothesized that the administration of DEX could reduce excessive DF proliferation and thus, facilitate the tenogenic differentiation of DFs using a previously established 3D organoid model combined with dose-dependent application of DEX. Interestingly, the results demonstrated that DEX, in all tested concentrations, was not sufficient to notably induce the tenogenic differentiation of human DFs and DEX-treated organoids did not have clear advantages over untreated control organoids. Moreover, high concentrations of DEX exerted a negative impact on the organoid phenotype. Nevertheless, the expression profile of tendon-related genes of untreated and 10 nM DEX-treated DF organoids was largely comparable to organoids formed by tendon-derived cells, which is encouraging for further investigations on utilizing DFs for tendon tissue engineering.
Medical tourism is a rapidly growing sector of economic growth and diversification. However, data on the demographics and characteristics of the traveling patients are sparse. In this study, we analyzed the common demographic properties and characteristics of the inbound medical tourists seeking orthopedic medical care in Germany for the years 2010 to 2019 compared to a domestic group. At the same time, we examined how the COVID-19 pandemic outbreak of 2020 changed the field of medical tourism in Germany. Calculations were performed using administrative hospital data provided by the Federal Statistical Department of Germany. Data were analyzed from the years 2010 to 2020. A total of six elective orthopedic surgery codes (bone biopsy, knee arthroplasty, foot surgery, osteotomy, hardware removal, and arthrodesis) were identified as key service indicators for medical tourism and further analyzed. Factors including residence, sex, year, and type of elective surgery were modeled using linear regression analysis. Age and sex distributions were compared between patients living inside Germany (DE) or outside Germany (non-DE). Between 2010 and 2020, 6,261,801 orthopedic procedures were coded for the DE group and 27,420 key procedures were identified for the non-DE group. Medical tourists were predominantly male and significantly younger than the domestic population. The linear regression analysis of the OPS codes over the past years showed a significantly different slope between the DE and non-DE groups only for the OPS code “hardware removal”. With the COVID-19 pandemic, an overall decline in performed orthopedic procedures was observed for the non-DE and the DE group. A significant reduction below the 95% prediction bands for the year 2020 could be shown for hardware removal and foot surgery (for DE), and for hardware removal, knee arthroplasty, foot surgery, and osteotomy (for non-DE). This study is the first to quantify inbound medical tourism in elective orthopedic surgery in Germany. The COVID-19 pandemic negatively affected many — but not all — areas of orthopedic surgery. It has to be seen how this negative trend will develop in the future.
Alignment strategies for primary total knee arthroplasty (TKA) have changed significantly over time with a shift towards a more individualized alignment goal. At the same time, computer-assisted surgery (CAS) has gained interest for intraoperative control and accuracy in implant positioning and limb alignment. Despite the often discussed benefits and drawbacks of robotics and navigation for TKA, the routine use of these new devices on a day-to-day basis remains obscure. Therefore, nationwide hospital billing data based on the Operation Procedure Classification System (OPS) were retrieved from the Federal Statistical Office of Germany for the period from 2010 to 2021. OPS codes for primary total knee arthroplasty (OPS code: 5-822*) were further analyzed regarding the usage of computer navigation (additional OPS code: 5-988) or robotic devices (additional OPS code: 5-987). Gender and age at the time of surgery were also assessed. The results show a total of 2,226,559 primary TKAs were implanted between 2010 and 2021, of which 2,044,914 were performed conventionally (91.84% of all TKAs). A total of 170,276 TKAs were performed using navigation technique (7.65% of all TKAs) and another 11,369 TKAs were performed using robotics (0.51% of all TKAs). For the period from 2018 to 2021, a substantial increase in robot-assisted TKA (R-TKA) was observed, with an average increase rate of 84.74% per year, while the number of navigated TKAs declined (−3.67% per year). Computer-assisted surgery, and particularly robotics for TKA, are seeing growing popularity and stepwise translation into routine clinical use in Germany, with a steep increase rate of more than 80% per year since 2018. Nevertheless, the majority of TKAs are still performed using manual instrumentation, rendering conventional TKA the currently unchanged gold standard.
Background and Objectives: Currently, the worldwide incidence of major amputations in the general population is decreasing whereas the incidence of minor amputations is increasing. The purpose of our study was to analyze whether this trend is reflected among orthopaedic patients treated with lower extremity amputation in our orthopaedic university institution. Materials and Methods: We conducted a single-center retrospective study and included patients referred to our orthopaedic department for lower extremity amputation (LEA) between January 2007 and December 2019. Acquired data were the year of amputation, age, sex, level of amputation and cause of amputation. T test and Chi² test were performed to compare age and amputation rates between males and females; significance was defined as p < 0.05. Linear regression and multivariate logistic regression models were used to test time trends and to calculate probabilities for LEA. Results: A total of 114 amputations of the lower extremity were performed, of which 60.5% were major amputations. The number of major amputations increased over time with a rate of 0.6 amputation/year. Men were significantly more often affected by LEA than women. Age of LEA for men was significantly below the age of LEA for women (men: 54.8 ± 2.8 years, women: 64.9 ± 3.2 years, p = 0.021). Main causes leading to LEA were tumors (28.9%) and implant-associated complications (25.4%). Implant-associated complications and age raised the probability for major amputation, whereas malformation, angiopathies and infections were more likely to cause a minor amputation. Conclusions: Among patients in our orthopaedic institution, etiology of amputations of the lower extremity is multifactorial and differs from other surgical specialties. The number of major amputations has increased continuously over the past years. Age and sex, as well as diagnosis, influence the type and level of amputation.
Testosterone deficiency in males is linked to various pathological conditions, including muscle and bone loss. This study evaluated the potential of different training modalities to counteract these losses in hypogonadal male rats. A total of 54 male Wistar rats underwent either castration (ORX, n = 18) or sham castration (n = 18), with 18 castrated rats engaging in uphill, level, or downhill interval treadmill training. Analyses were conducted at 4, 8, and 12 weeks postsurgery. Muscle force of the soleus muscle, muscle tissue samples, and bone characteristics were analyzed. No significant differences were observed in cortical bone characteristics. Castrated rats experienced decreased trabecular bone mineral density compared to sham-operated rats. However, 12 weeks of training increased trabecular bone mineral density, with no significant differences among groups. Muscle force measurements revealed decreased tetanic force in castrated rats at week 12, while uphill and downhill interval training restored force to sham group levels and led to muscle hypertrophy compared to ORX animals. Linear regression analyses showed a positive correlation between bone biomechanical characteristics and muscle force. The findings suggest that running exercise can prevent bone loss in osteoporosis, with similar bone restoration effects observed across different training modalities.
Knochenmetastasen sind unter den drei häufigsten Manifestationsorten metastatischer Absiedelungen von fortgeschrittenen Tumorerkrankungen. Dabei sind insbesondere Patientinnen und Patienten mit Prostata- und Mammakarzinom von Knochenmetastasen betroffen. Diese Knochenmetastasen führen häufig zu einer deutlichen Verschlechterung der Lebensqualität und zu einer Begrenzung der Therapieoptionen auf lediglich palliative Ansätze.
Die biologisch aktive Form von Vitamin D3, 1,25(OH)2-Vitamin D3, zeigt in präklinischen Studien antiproliferative und differenzierende Effekte auf Tumorzellen (101, 102, 104), die haupsächlich durch die Bindung an den Vitamin D-Rezeptor (VDR) vermittelt werden. Darüberhinaus konnte präklinisch gezeigt werden, dass eine niedrige Expression des VDRs, ligandenunabhängig, die Knochenmetastasierung und das Tumorwachstum begünstigt (118). Eine niedrige VDR-Expression ist in Primärtumoren in klinischen Studien mit aggressiven Tumoreigenschaften assoziiert (111, 113, 115) und kann zudem mit einer erhöhten/früheren ossären Metastasierung einhergehen (167). Zudem gibt es Hinweise auf einen dysregulierten 1,25(OH)2-Vitamin D3-Katabolismus durch eine erhöhte Expression des 1,25(OH)2-Vitamin D3 katabolisierenden Enzyms CYP24A1/24-Hydroxylase in primärem Tumorzellen (70, 121, 122). Durch die Untersuchungen der Primärtumoren ist damit zu hypothetisieren, dass die Expression des VDRs und von CYP24A1 bei der Tumorprogression und Knochenmetastasierung von Bedeutung sein könnte. Entsprechende Untersuchungen des VDRs und der 24-Hydroxylase in Knochenmetastasen fehlen allerdings. Deshalb wurde in dieser Arbeit die Expression des VDRs und von CYP24A1 in Knochenmetastasen unterschiedlicher Primärtumoren von 66 Patientinnen und Patienten untersucht und mögliche Assoziationen mit aggressiven Tumoreigenschaften analysiert.
Der VDR konnte sowohl im Zytoplasma als auch im Nukleus nachgewiesen werden, während CYP24A1 nur im Zytoplasma lokalisiert war. Dabei wiesen insgesamt 71 % der Knochenmetastasen eine hohe VDR-Expression im Nukleus und 56 % im Zytoplasma auf. 59 % der Knochenmetastasen wiesen eine hohe Expression des VDRs insgesamt auf. CYP24A1 war ebenso in 59 % der Knochenmetastasen hoch exprimiert. Bei der Auswertung des Zusammenhangs zwischen den TNM-Stadien und des Gradings zeigte sich ein nicht signifikanter Trend von schlecht differenzierten Tumoren hin zu einer niedrigeren nukleären VDR-Expression (p=0.07, siehe Abbildung 33). Bezüglich der T-Stadien zeigten sich keine Unterschiede der Expression des VDRs und von CYP24A1 in den Knochenmetastasen zwischen lokal fortgeschrittenen und kleinen Primärtumoren. Weiterhin hatten Patientinnen und Patienten mit Lymphknotenmetastasen tendenziell eine verminderte VDR- und auch CYP24A1-Expression in den Knochenmetastasen im Vergleich zu Patienten und Patientinnen ohne Lymphknotenmetastasen (pVDR=0.15, pCYP24A1=0.06, siehe Abbildung 35). Außerdem hatten Patientinnen und Patienten mit multiple metastasierten Tumoren eine signifikant niedrigere nukleäre VDR- und auch CYP24A1-Expression im Vergleich zu Patientinnen und Patienten mit ausschließlich ossärer Metastasierung (pVDR=0.03, pCYP24A1=0.01, Abbildung 36). Die Proteinexpression des VDRs- und von CYP24A1 korrelierten signifikant (p=0.001).
Somit konnte mit dieser Arbeit die Proteinexpression des VDRs und von CYP24A1 in Knochenmetastasen durch Immunhistologie nachgewiesen werden. Insgesamt wurde der VDR und CYP24A1 von Knochenmetastasen diverser Entität unterschiedlich stark exprimiert. Jedoch könnten insbesondere Patienten mit VDR-exprimierenden Knochenmetastasen von einer Vitamin D3-Supplementierung profitieren, die häufig einen 25-OH-Vitamin D3 Mangel zeigen (165, 166). Ebenso könnte eine Untersuchung auf einen niedrigen VDR-Status in Primärtumoren dabei helfen, Krebspatienten mit einem hohen Metastasierungsrisiko zu identifizieren. Allerdings sind weitere und größere Studien inbesondere mit Evaluation des gesamten Vitamin D-Metabolismus und -Signalwegs notwendig, um diesen Zusammenhang weiter zu untersuchen.
In March 2020, Germany imposed a nationwide lockdown to curb the spread of COVID-19, prompting questions about the impact on the incidence of common fractures. This study examined 15 fracture types in pre-outbreak (2010–2019) and post-outbreak (2020–2021) periods, using data categorized by age (18–64 years, 65 years) and sex (male, female). Linear regression assessed annual growth rates, and mean fracture numbers were compared across periods for significant differences. Results indicated a positive correlation between fracture incidence rates and time for various types, such as cervical, thoracic, lumbar, and pelvic spine fractures, rib fractures, femoral neck, pertrochanteric femur, femoral shaft, and ankle fractures. Frequencies of proximal humerus, distal radius, femoral neck, pertrochanteric femur, femoral shaft, and ankle fractures in 2020 and 2021 were within predicted ranges from previous years. However, rib fractures and spinal fractures (cervical, thoracic, lumbar, and pelvic spine) occurred less frequently during this time. Notably, this study found a consistent decline in most fracture types for individuals aged 18–64 after the pandemic’s onset, while the fracture incidence of hip fractures, often referred to as fragility fractures, for those over 65 remained unchanged. Fibula fractures showed the most considerable decrease in both age groups. In conclusion, the COVID-19 pandemic substantially impacted fracture incidence, with lower rates among individuals under 65 and unchanged fragility fractures in the elderly population.
Background and objectives: Cartilage surgery constitutes a standard intervention in foot and ankle procedures. Currently, there is a lack of epidemiological data on its frequency, age distribution, and surgical options for cartilage surgery. This study aimed to investigate the current landscape of cartilage surgery in Germany and identify the most common procedures from an epidemiological standpoint. Materials and methods: Medical billing and reporting data from the Federal Statistical Office of Germany, encompassing the period 2006–2020, was examined, including all foot and ankle cartilage surgical procedures (summarized under OPS codes 5-812 and 5-801). The dataset incorporated information on the affected joint, patient age and sex, and surgery type. Each surgical procedure was categorized as “debridement”, “regeneration” or “refixation”. Linear and nonlinear regression analyses were employed, with a statistical significance threshold of 0.05. Results: From the total of 136,501 procedures conducted during the study period, the most frequently performed interventions were microfracture (58,252) and chondroplasty (56,135), and thus, debridement procedures were in the leading position. The use of acellular membranes was the most used regenerative technique (n = 11,414). At the ankle joint, interventions were mostly arthroscopic and in men, while foot cartilage surgeries were preferably performed via open surgery and mostly in women. Age distribution analysis revealed two primary peaks: the first in the 20–25-year-old group (ankle and foot) and the second in the 45–50-year-old group (ankle) and 55–60-year-old group (foot). Refixation and regenerative procedures were more frequent among younger individuals, while debriding procedures were more frequent among older individuals. Regenerative procedures, particularly in the ankle, significantly increased over time. Conclusions: Cartilage surgery of the foot and ankle was common, with two primary age groups predominantly affected. Notably, recent years have witnessed a considerable rise in cartilage regenerative procedures.
Im Rhön-Klinikum wurden von 2012 bis 2015 49 Patient*innen wegen eines Glenoiddefektes mittels offenem Beckenkammspantransfer mit Kapselshift bei anteriorer Schulterinstabilität behandelt. 27 Patienten konnten in dieser Studie eingeschlossen werden (Einschlusskriterien: Follow-up von mindestens 12 Monaten, kompletter präoperativer 3D-CT-Datensatz / Ausschlusskriterien: traumatische Schulterluxation oder Voroperation der kontralateralen Schulter). Ziel der Studie war es, das kurz- bis mittelfristige klinische Outcome dieser Kohorte zu erfassen, der Vergleich mit Ergebnissen anderer Arbeitsgruppen und der Vergleich von präoperativ verwendeten Messmethoden (Chuang- bzw. Wambacher-Methode) für den Glenoiddefekt. Bei einem mittleren Follow-up von 27,11 Monaten zeigten sich überwiegend gute bis exzellente kurz- bis mittelfristige OP-Ergebnisse (Rowe-Score: 84,81, Oxford-Shoulder-Score: 20,56, WOSI-Score: 371, Constant-Score: 86,74). Die OP-Methode eignet sich gut für Patient*innen, die mehrfach voroperiert sind, multiple Luxationsereignisse hatten sowie für diejenigen mit relevanter Hyperlaxizität, bei denen eine Latarjet-Operation kontraindiziert ist. Die OP-Methode ist gut anwendbar bei Patient*innen mit subkritischem Glenoidverlust < 20 %, wenn zusätzliche Sekundärfaktoren vorliegen. Eine postoperative Omarthrose ist ein Risikofaktor für ein signifikant schlechteres Outcome. Die Gesamtkomplikationsrate lag bei 25,9%, der Großteil hiervon (18,3%) waren innerhalb kurzer Zeit reversibel. Die Reluxationsrate lag bei 3,7%. Bei allen Studienteilnehmenden kam es zum Span-Remodelling ohne Schraubenlockerung oder Spanbruch. Eine übermäßige Spanresorbtion erfolgt antero-inferior, während um die Osteosyntheseschrauben eine Überkontur persistiert. Die Glenoiddefekte lagen bei 23,39 % (Chuang) bzw. 22,06 % (Wambacher). Es zeigte sich eine gute Übereinstimmung der Messergebnisse beider Methoden, allerdings lagen die Werte nach Chuang signifikant höher.
Retrospektive Untersuchung von prä- und postoperativ erhobener Datensätze von 60 Patienten, die über einen minimal-invasiven anterioren Zugang mit einer Nanos-Kurzschaftprothese versorgt wurden. Auswertung und Analyse des Outcome an Hand von 3 in der Literatur etablierten Fragebögen (PROM) WOMAC, EurQol und Harris Hip Score und Vergleich der Ergebnisse mit der Literatur.
Akute Patellaluxationen sind häufige Kniegelenksverletzungen. Sie gehen oft mit einer Verletzung des medialen patellofemoralen Ligaments (MPFL) einher, was zu rezidivierenden Patellaluxationen und patellofemoraler Instabilität führen kann. Ein möglicher Therapieansatz ist die Rekonstruktion des MPFL.
Zahlreiche Operationstechniken sind hierzu in der Literatur beschrieben, darunter Fixationen mit Interferenzschrauben, Bohrkanälen, Nahtankern oder Nahtfixationen am Knochen oder Weichgewebe. Sie werden meist mit einem autologen Sehnentransplantats durchgeführt und unterscheiden sich hauptsächlich in der Art dessen patellarer Fixation.
Meta-Analysen zeigen nach wie vor hohe Komplikationsraten und teilweise wenig zufriedenstellende Ergebnisse etablierter MPFL-Rekonstruktionen.
Ein vielversprechender Ansatz zur Senkung der Komplikationsraten sind patellare Fixationsmethoden, die auf das Einbringen von Fremdmaterial und Bohrungen durch die Patella verzichten. Solche implantat- und/oder bohrkanalfreien Fixationsmethoden sind bereits in der Literatur beschrieben, bis jetzt existieren jedoch nur wenige Studien zu deren biomechanischen Eigenschaften.
Ziel dieser Arbeit war der Vergleich biomechanischer Eigenschaften von fünf unterschiedlichen implantatfreien patellaren Fixationsmethoden beim MPFL- Ersatz mit dem nativen MPFL und mit nativen Extensorensehnen. Dazu wurde ein porcines Modell benutzt. Die Hypothese dieser Studie war, dass die patellare Weichteilfixation eines autologen Sehnentransplantats ohne Implantate oder Bohrkanal eine vergleichbare primäre Ausrissfestigkeit wie das native MPFL zeigt.
60 Patellae und Extensorensehnen wurden aus porcinen Hinterläufen extrahiert und randomisiert auf 6 Versuchsgruppen aufgeteilt (n=10). In den Gruppen 1 und 2 wurden patellare Weichteilfixationen getestet. In den Gruppen 3 und 4 wurden Bohrkanalfixationen mit unterschiedlichem Nahtmaterial durchgeführt (Gruppe 3: resorbierbarer Faden der Stärke USP 0, Gruppe 4: nicht-resorbierbarer Faden der Stärke USP 3). In Gruppe 5 erfolgte die patellare Fixation mittels V-förmigen Bohrkanal mit Durchmesser von 4,5 mm. In der sechsten Versuchsgruppe wurde zum Vergleich das native Gewebe getestet. In einer weiteren Versuchsgruppe wurden native porcine Extensorensehnen biomechanisch untersucht.
Die biomechanische Testung gliederte sich in mehrere Abschnitte. Zunächst erfolgte eine Präkonditionierung mit 10 Setzzyklen mit einem Kraftintervall von 5 - 20 N. Es folgte eine zyklische Testphase von 1000 Messzyklen mit einem Kraftintervall von 5 - 50 N. Im Anschluss wurde die maximale Kraft bis zum Versagen angewendet. Dabei wurden die Parameter maximale Ausrisskraft, Yield Load, Steifigkeit, Elongation nach 1000 Zyklen sowie die Versagensart untersucht. In der Versuchsgruppe des nativen Gewebes wurde direkt die maximale Kraft bis zum Versagen angewendet.
Die höchsten maximalen Ausrisskräfte wurden in Gruppen 1 und 2 gemessen (321,8 ± 53,5 N und 242,0 ± 57,4 N) und waren mit dem nativen Gewebe vergleichbar (252,1 ± 129,3 N, p > 0,05). Ein signifikant niedrigerer Yield Load im Vergleich zum nativen Gewebe zeigte sich in den Gruppen 3 (p < 0,01) und 4 (p = 0,01). Während der zyklischen Belastung war die Elongation der Präparate in Gruppe 3 signifikant höher im Vergleich zu den anderen Gruppen (5,3 ± 1 mm, p < 0,05). Alle Gruppen wiesen ähnliche Steifigkeiten wie das native Gewebe vor (p > 0,05). Die getesteten Fixationsmethoden zeigten signifikante Unterschiede in ihren biomechanischen Eigenschaften (p < 0,05). Insbesondere die Weichteilfixationen in Gruppen 1 und 2 wiesen adäquate biomechanische Eigenschaften im Vergleich zum nativen Gewebe vor.
Durch die Kombination aus geringerer Invasivität, Verzicht auf das Einbringen von Fremdkörpern, einfacher Anwendbarkeit und guter Primärstabilität sind patellare Weichteilfixationen vielversprechende Alternativen bei der MPFL-Rekonstruktion.
und guter Primärstabilität sind patellare Weichteilfixationen vielversprechende Alternativen bei der MPFL-Rekonstruktion.