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Institute
- Lehrstuhl für Orthopädie (34) (remove)
Sonstige beteiligte Institutionen
EU-Project number / Contract (GA) number
- EU-1650-0006 (1)
In the adult skeleton, bone remodeling is required to replace damaged bone and functionally adapt bone mass and structure according to the mechanical requirements. It is regulated by multiple endocrine and paracrine factors, including hormones and growth factors, which interact in a coordinated manner. Because the response of bone to mechanical signals is dependent on functional estrogen receptor (ER) and Wnt/β-catenin signaling and is impaired in postmenopausal osteoporosis by estrogen deficiency, it is of paramount importance to elucidate the underlying mechanisms as a basis for the development of new strategies in the treatment of osteoporosis. The present study aimed to investigate the effectiveness of the activation of the ligand-dependent ER and the Wnt/β-catenin signal transduction pathways on mechanically induced bone formation using ovariectomized mice as a model of postmenopausal bone loss. We demonstrated that both pathways interact in the regulation of bone mass adaption in response to mechanical loading and that the activation of Wnt/β-catenin signaling considerably increased mechanically induced bone formation, whereas the effects of estrogen treatment strictly depended on the estrogen status in the mice.
The present study aimed to evaluate the effect of high intensity dynamic resistance exercise (HIT-DRT) and whey protein supplementation (WPS) on bone mineral density (BMD) and sarcopenia parameters in osteosarcopenic men. Men ≥ 72 years with osteosarcopenia (n = 43) were randomly assigned to a HIT-RT (HIT-RT: n = 21) or a non-training control group (n = 22). Supervised HIT-RT twice/week was applied for 18 months, while the control group maintained their habitual lifestyle. Supplying WPS, total protein intake amounted to 1.5–1.6 (HIT-RT) and 1.2 g/kg/body mass/d (control). Both groups were supplied with calcium and vitamin D. Primary study outcomes were BMD and the sarcopenia Z-score. After adjusting for multiplicity, we observed significant positive effects for sarcopenia Z-score (standardized mean difference (SMD): 1.40), BMD at lumbar spine (SMD: 0.72) and total hip (SMD: 0.72). In detail, effect sizes for skeletal muscle mass changes were very pronounced (1.97, p < 0.001), while effects for functional sarcopenia parameters were moderate (0.87, p = 0.008; handgrip strength) or low (0.39, p = 0.209; gait velocity). Apart from one man who reported short periods of temporary worsening of existing joint pain, no HIT-RT/WPS-related adverse effects or injuries were reported. We consider HIT-RT supported by whey protein supplementation as a feasible, attractive, safe and highly effective option to fight osteosarcopenia in older men.
Muscle and bone interact via physical forces and secreted osteokines and myokines. Physical forces are generated through gravity, locomotion, exercise, and external devices. Cells sense mechanical strain via adhesion molecules and translate it into biochemical responses, modulating the basic mechanisms of cellular biology such as lineage commitment, tissue formation, and maturation. This may result in the initiation of bone formation, muscle hypertrophy, and the enhanced production of extracellular matrix constituents, adhesion molecules, and cytoskeletal elements. Bone and muscle mass, resistance to strain, and the stiffness of matrix, cells, and tissues are enhanced, influencing fracture resistance and muscle power. This propagates a dynamic and continuous reciprocity of physicochemical interaction. Secreted growth and differentiation factors are important effectors of mutual interaction. The acute effects of exercise induce the secretion of exosomes with cargo molecules that are capable of mediating the endocrine effects between muscle, bone, and the organism. Long-term changes induce adaptations of the respective tissue secretome that maintain adequate homeostatic conditions. Lessons from unloading, microgravity, and disuse teach us that gratuitous tissue is removed or reorganized while immobility and inflammation trigger muscle and bone marrow fatty infiltration and propagate degenerative diseases such as sarcopenia and osteoporosis. Ongoing research will certainly find new therapeutic targets for prevention and treatment.
Hypophosphatasia (HPP) is a rare, inherited, metabolic disease caused by deficient tissue non‐specific alkaline phosphatase activity. This study aims to assess patient‐reported pain, disability and health‐related quality of life (HRQoL) in a real‐world cohort of adults with HPP who were not receiving asfotase alfa during the analysis. Adults (≥18 years old) with HPP (confirmed by ALPL gene mutation and/or low serum alkaline phosphatase activity for age/sex) were identified from the Global HPP Registry (NCT02306720). Demographics, clinical characteristics, and data on patient‐reported pain, disability, and HRQoL (assessed by Brief Pain Inventory Short Form [BPI‐SF], Health Assessment Questionnaire Disability Index [HAQ‐DI], and 36‐Item Short‐Form Health Survey version 2 [SF‐36v2], respectively) were stratified by pediatric‐ and adult‐onset HPP and summarized descriptively. Of the 304 adults included (median [min, max] age 48.6 [18.8, 79.8] years; 74% women), 45% had adult‐onset HPP and 33% had pediatric‐onset HPP (unknown age of onset, 22%). Of those with data, 38% had experienced ≥5 HPP manifestations and 62% had a history of ≥1 fracture/pseudofracture. Median (Q1, Q3) BPI‐SF scores were 3.5 (1.5, 5.3) for pain severity and 3.3 (0.9, 6.2) for pain interference. Median (Q1, Q3) disability on the HAQ‐DI was 0.3 (0.0, 0.7). Median (Q1, Q3) physical and mental component summary scores on the SF‐36v2 were 42.4 (32.7, 49.9) and 45.3 (36.3, 54.8), respectively. Greater numbers of HPP manifestations experienced/body systems affected correlated significantly with poorer scores on the BPI‐SF, HAQ‐DI, and SF‐36v2 (all p < 0.05). No significant differences between adults with pediatric‐ and adult‐onset HPP were observed for patient‐reported outcomes, except for disability and the BPI‐SF question “pain at its worst,” which were significantly higher among adults with pediatric‐ versus adult‐onset HPP (p = 0.03 and 0.04, respectively). These data from the Global HPP Registry show that adults with HPP have a substantial burden of illness that is associated with reduced patient‐reported HRQoL, regardless of age of disease onset.
Background
The treatment of septic arthritis, caused by either hematogenous seeding, injections, or surgery, can be challenging. Staged reverse shoulder arthroplasty (RSA) with temporary implantation of an antibiotic-loaded spacer is widely accepted but still discussed controversially. This study investigated the shoulder-specific bacterial spectrum, infection control rate, functional outcome, and infection-free survival rate after staged RSA in the mid- to long-term follow-up. It was hypothesized that staged RSA would show a high infection-free survival rate.
Methods
A total of 39 patients treated with staged RSA for primary septic arthritis (n = 8), secondary infection (n = 8), or periprosthetic infection (n = 23) were retrospectively included. The infection control rate was calculated based on cultures taken intraoperatively at spacer removal and RSA implantation. Infection-free survival was defined as no revision due to infection. The minimum follow-up period for functional outcome assessment was 2 years (n = 14; mean, 76 months; range, 31-128 months).
Results
Cutibacterium (26%) and coagulase-negative staphylococci (23%) were the predominant pathogens. The infection control rate was 90%. The cumulative infection-free survival rate was 91% after 128 months. Follow-up examinations showed a mean Constant score of 48 (range, 7-85), a mean QuickDASH (short version of Disabilities of the Arm, Shoulder and Hand questionnaire) score of 40.0 (range, 11.4-93.3), and a mean pain score of 1.6 (range, 0-7).
Conclusion
Staged RSA implantation was confirmed to be a reliable treatment option for primary, secondary, and periprosthetic infections of the shoulder. The infection control rate and infection-free survival rate are satisfactory. However, patients and surgeons must be aware of functional impairment even after successful treatment of infections.
Background
For improved outcomes in total knee arthroplasty (TKA) correct implant fitting and positioning are crucial. In order to facilitate a best possible implant fitting and positioning patient-specific systems have been developed. However, whether or not these systems allow for better implant fitting and positioning has yet to be elucidated. For this reason, the aim was to analyse the novel patient-specific cruciate retaining knee replacement system iTotal (TM) CR G2 that utilizes custom-made implants and instruments for its ability to facilitate accurate implant fitting and positioning including correction of the hip-knee-ankle angle (HKA).
Methods
We assessed radiographic results of 106 patients who were treated with the second generation of a patient-specific cruciate retaining knee arthroplasty using iTotal\(^{TM}\) CR G2 (ConforMIS Inc.) for tricompartmental knee osteoarthritis (OA) using custom-made implants and instruments. The implant fit and positioning as well as the correction of the mechanical axis (hip-knee-ankle angle, HKA) and restoration of the joint line were determined using pre- and postoperative radiographic analyses.
Results
On average, HKA was corrected from 174.4 degrees +/- 4.6 degrees preoperatively to 178.8 degrees +/- 2.2 degrees postoperatively and the coronal femoro-tibial angle was adjusted on average 4.4 degrees. The measured preoperative tibial slope was 5.3 degrees +/- 2.2 degrees (mean +/- SD) and the average postoperative tibial slope was 4.7 degrees +/- 1.1 degrees on lateral views. The joint line was well preserved with an average modified Insall-Salvati index of 1.66 +/- 0.16 pre- and 1.67 +/- 0.16 postoperatively. The overall accuracy of fit of implant components was decent with a measured medial overhang of more than 1 mm (1.33 mm +/- 0.32 mm) in 4 cases only. Further, a lateral overhang of more than 1 mm (1.8 mm +/- 0.63) (measured in the anterior-posterior radiographs) was observed in 11 cases, with none of the 106 patients showing femoral notching.
Conclusion
The patient-specific iTotal\(^{TM}\) CR G2 total knee replacement system facilitated a proper fitting and positioning of the implant components. Moreover, a good restoration of the leg axis towards neutral alignment was achieved as planned. Nonetheless, further clinical follow-up studies are necessary to validate our findings and to determine the long-term impact of using this patient- specific system.
Dynamic resistance exercise (DRT) might be the most promising agent for fighting sarcopenia in older people. However, the positive effect of DRT on osteopenia/osteoporosis in men has still to be confirmed. To evaluate the effect of low‐volume/high‐intensity (HIT)‐DRT on bone mineral density (BMD) and skeletal muscle mass index (SMI) in men with osteosarcopenia, we initiated the Franconian Osteopenia and Sarcopenia Trial (FrOST). Forty‐three sedentary community‐dwelling older men (aged 73 to 91 years) with osteopenia/osteoporosis and SMI‐based sarcopenia were randomly assigned to a HIT‐RT exercise group (EG; n = 21) or a control group (CG; n = 22). HIT‐RT provided a progressive, periodized single‐set DRT on machines with high intensity, effort, and velocity twice a week, while CG maintained their lifestyle. Both groups were adequately supplemented with whey protein, vitamin D, and calcium. Primary study endpoint was integral lumbar spine (LS) BMD as determined by quantitative computed tomography. Core secondary study endpoint was SMI as determined by dual‐energy X‐ray absorptiometry. Additional study endpoints were BMD at the total hip and maximum isokinetic hip−/leg‐extensor strength (leg press). After 12 months of exercise, LS‐BMD was maintained in the EG and decreased significantly in the CG, resulting in significant between‐group differences (p < 0.001; standardized mean difference [SMD] = 0.90). In parallel, SMI increased significantly in the EG and decreased significantly in the CG (p < 0.001; SMD = 1.95). Total hip BMD changes did not differ significantly between the groups (p = 0.064; SMD = 0.65), whereas changes in maximum hip−/leg‐extensor strength were much more prominent (p < 0.001; SMD = 1.92) in the EG. Considering dropout (n = 2), attendance rate (95%), and unintended side effects/injuries (n = 0), we believe our HIT‐RT protocol to be feasible, attractive, and safe. In summary, we conclude that our combined low‐threshold HIT‐RT/protein/vitamin D/calcium intervention was feasible, safe, and effective for tackling sarcopenia and osteopenia/osteoporosis in older men with osteosarcopenia.
Background
Hypophosphatasia (HPP) is a rare, inherited metabolic disorder caused by loss-of-function mutations in the ALPL gene that encodes the tissue-nonspecific alkaline phosphatase TNAP (ORPHA 436). Its clinical presentation is highly heterogeneous with a remarkably wide-ranging severity. HPP affects patients of all ages. In children HPP-related musculoskeletal symptoms may mimic rheumatologic conditions and diagnosis is often difficult and delayed. To improve the understanding of HPP in children and in order to shorten the diagnostic time span in the future we studied the natural history of the disease in our large cohort of pediatric patients. This single centre retrospective chart review included longitudinal data from 50 patients with HPP diagnosed and followed at the University Children's Hospital Wuerzburg, Germany over the last 25 years.
Results
The cohort comprises 4 (8%) perinatal, 17 (34%) infantile and 29 (58%) childhood onset HPP patients. Two patients were deceased at the time of data collection. Diagnosis was based on available characteristic clinical symptoms (in 88%), low alkaline phosphatase (AP) activity (in 96%), accumulating substrates of AP (in 58%) and X-ray findings (in 48%). Genetic analysis was performed in 48 patients (31 compound heterozygous, 15 heterozygous, 2 homozygous mutations per patient), allowing investigations on genotype-phenotype correlations. Based on anamnestic data, median age at first clinical symptoms was 3.5 months (min. 0, max. 107), while median time to diagnosis was 13 months (min. 0, max. 103). Common symptoms included: impairment of motor skills (78%), impairment of mineralization (72%), premature loss of teeth (64%), musculoskeletal pain and craniosynostosis (each 64%) and failure to thrive (62%). Up to now 20 patients started medical treatment with Asfotase alfa.
Conclusions
Reported findings support the clinical perception of HPP being a chronic multi-systemic disease with often delayed diagnosis. Our natural history information provides detailed insights into the prevalence of different symptoms, which can help to improve and shorten diagnostics and thereby lead to an optimised medical care, especially with promising therapeutic options such as enzyme-replacement-therapy with Asfotase alfa in mind.
Objective
As native cartilage consists of different phenotypical zones, this study aims to fabricate different types of neocartilage constructs from collagen hydrogels and human mesenchymal stromal cells (MSCs) genetically modified to express different chondrogenic factors.
Design
Human MSCs derived from bone-marrow of osteoarthritis (OA) hips were genetically modified using adenoviral vectors encoding sex-determining region Y-type high-mobility-group-box (SOX)9,transforming growth factor beta (TGFB) 1or bone morphogenetic protein (BMP) 2cDNA, placed in type I collagen hydrogels and maintained in serum-free chondrogenic media for three weeks. Control constructs contained unmodified MSCs or MSCs expressing GFP. The respective constructs were analyzed histologically, immunohistochemically, biochemically, and by qRT-PCR for chondrogenesis and hypertrophy.
Results
Chondrogenesis in MSCs was consistently and strongly induced in collagen I hydrogels by the transgenesSOX9,TGFB1andBMP2as evidenced by positive staining for proteoglycans, chondroitin-4-sulfate (CS4) and collagen (COL) type II, increased levels of glycosaminoglycan (GAG) synthesis, and expression of mRNAs associated with chondrogenesis. The control groups were entirely non-chondrogenic. The levels of hypertrophy, as judged by expression of alkaline phosphatase (ALP) and COL X on both the protein and mRNA levels revealed different stages of hypertrophy within the chondrogenic groups (BMP2>TGFB1>SOX9).
Conclusions
Different types of neocartilage with varying levels of hypertrophy could be generated from human MSCs in collagen hydrogels by transfer of genes encoding the chondrogenic factorsSOX9,TGFB1andBMP2. This technology may be harnessed for regeneration of specific zones of native cartilage upon damage.
Background
The role of cement-augmented screw fixation for calcaneal fracture treatment remains unclear. Therefore, this study was performed to biomechanically analyze screw osteosynthesis by reinforcement with either a calcium phosphate (CP)-based or polymethylmethacrylate (PMMA)-based injectable bone cement.
Methods
A calcaneal fracture (Sanders type IIA) including a central cancellous bone defect was generated in 27 synthetic bones, and the specimens were assigned to 3 groups. The first group was fixed with four screws (3.5 mm and 6.5 mm), the second group with screws and CP-based cement (Graftys (R) QuickSet; Graftys, Aix-en-Provence, France), and the third group with screws and PMMA-based cement (Traumacem (TM) V+; DePuy Synthes, Warsaw, IN, USA). Biomechanical testing was conducted to analyze peak-to-peak displacement, total displacement, and stiffness in following a standardized protocol.
Results
The peak-to-peak displacement under a 200-N load was not significantly different among the groups; however, peak-to-peak displacement under a 600- and 1000-N load as well as total displacement exhibited better stability in PMMA-augmented screw osteosynthesis compared to screw fixation without augmentation. The stiffness of the construct was increased by both CP- and PMMA-based cements.
Conclusion
Addition of an injectable bone cement to screw osteosynthesis is able to increase fixation strength in a biomechanical calcaneal fracture model with synthetic bones. In such cases, PMMA-based cements are more effective than CP-based cements because of their inherently higher compressive strength. However, whether this high strength is required in the clinical setting for early weight-bearing remains controversial, and the non-degradable properties of PMMA might cause difficulties during subsequent interventions in younger patients.
Vitamin D deficiency is a global health concern that is estimated to afflict over one billion people globally. The major role of vitamin D is that of a regulator of calcium and phosphate metabolism, thus, being essential for proper bone mineralisation. Concomitantly, vitamin D is known to exert numerous extra-skeletal actions. For example, it has become evident that vitamin D has direct anti-proliferative, pro-differentiation and pro-apoptotic actions on cancer cells. Hence, vitamin D deficiency has been associated with increased cancer risk and worse prognosis in several malignancies. We have recently demonstrated that vitamin D deficiency promotes secondary cancer growth in bone. These findings were partly attributable to an increase in bone remodelling but also through direct effects of vitamin D on cancer cells. To date, very little is known about vitamin D status of patients with bone tumours in general. Thus, the objective of this study was to assess vitamin D status of patients with diverse bone tumours. Moreover, the aim was to elucidate whether or not there is an association between pre-diagnostic vitamin D status and tumour malignancy in patients with bone tumours.
In a multi-center analysis, 25(OH)D, PTH and calcium levels of 225 patients that presented with various bone tumours between 2017 and 2018 were assessed. Collectively, 76% of all patients had insufficient vitamin D levels with a total mean 25(OH)D level of 21.43 ng/ml (53.58 nmol/L). In particular, 52% (117/225) of patients were identified as vitamin D deficient and further 24% of patients (55/225) were vitamin D insufficient. Notably, patients diagnosed with malignant bone tumours had significantly lower 25(OH)D levels than patients diagnosed with benign bone tumours [19.3 vs. 22.75 ng/ml (48.25 vs. 56.86 nmol/L); p = 0.04).
In conclusion, we found a widespread and distressing rate of vitamin D deficiency and insufficiency in patients with bone tumours. However, especially for patients with bone tumours sufficient vitamin D levels seem to be of great importance. Thus, we believe that 25(OH)D status should routinely be monitored in these patients. Collectively, there should be an increased awareness for physicians to assess and if necessary correct vitamin D status of patients with bone tumours in general or of those at great risk of developing bone tumours.
Hypophosphatasia (HPP) is a rare genetic disease with diverse symptoms and a heterogeneous severity of onset with underlying mutations in the ALPL gene encoding the ectoenzyme Tissue-nonspecific alkaline phosphatase (TNAP). Considering the establishment of zebrafish (Danio rerio) as a new model organism for HPP, the aim of the study was the spatial and temporal analysis of alpl expression in embryos and adult brains. Additionally, we determined functional consequences of Tnap inhibition on neural and skeletal development in zebrafish. We show that expression of alpl is present during embryonic stages and in adult neuronal tissues. Analyses of enzyme function reveal zones of pronounced Tnap-activity within the telencephalon and the mesencephalon. Treatment of zebrafish embryos with chemical Tnap inhibitors followed by axonal and cartilage/mineralized tissue staining imply functional consequences of Tnap deficiency on neuronal and skeletal development. Based on the results from neuronal and skeletal tissue analyses, which demonstrate an evolutionary conserved role of this enzyme, we consider zebrafish as a promising species for modeling HPP in order to discover new potential therapy strategies in the long-term.
Background
While multiple in vitro studies examined mesenchymal stromal cells (MSCs) derived from bone marrow or hyaline cartilage, there is little to no data about the presence of MSCs in the joint capsule or the ligamentum capitis femoris (LCF) of the hip joint. Therefore, this in vitro study examined the presence and differentiation potential of MSCs isolated from the bone marrow, arthritic hyaline cartilage, the LCF and full-thickness samples of the anterior joint capsule of the hip joint.
Methods
MSCs were isolated and multiplied in adherent monolayer cell cultures. Osteogenesis and adipogenesis were induced in monolayer cell cultures for 21 days using a differentiation medium containing specific growth factors, while chondrogenesis in the presence of TGF-ss1 was performed using pellet-culture for 27 days. Control cultures were maintained for comparison over the same duration of time. The differentiation process was analyzed using histological and immunohistochemical stainings as well as semiquantitative RT-PCR for measuring the mean expression levels of tissue-specific genes.
Results
This in vitro research showed that the isolated cells from all four donor tissues grew plastic-adherent and showed similar adipogenic and osteogenic differentiation capacity as proven by the histological detection of lipid droplets or deposits of extracellular calcium and collagen type I. After 27 days of chondrogenesis proteoglycans accumulated in the differentiated MSC-pellets from all donor tissues. Immunohistochemical staining revealed vast amounts of collagen type II in all differentiated MSC-pellets, except for those from the LCF. Interestingly, all differentiated MSCs still showed a clear increase in mean expression of adipogenic, osteogenic and chondrogenic marker genes. In addition, the examination of an exemplary selected donor sample revealed that cells from all four donor tissues were clearly positive for the surface markers CD44, CD73, CD90 and CD105 by flow cytometric analysis.
Conclusions
This study proved the presence of MSC-like cells in all four examined donor tissues of the hip joint. No significant differences were observed during osteogenic or adipogenic differentiation depending on the source of MSCs used. Further research is necessary to fully determine the tripotent differentiation potential of cells isolated from the LCF and capsule tissue of the hip joint.
Background: The soft tissue of the central pretibial area is difficult to reconstruct often requiring free tissue transfer. Especially medi- cally compromised patients are not ideal candidates for free tissue transfer and may benefit from expeditiously harvested local flaps with limited donor site morbidity. As muscle flaps are rare, pedi- cled flaps based on lateral perforators represent an alternative as the arc of rotation can often be limited to 90 °.
Material and Methods: A retrospective analysis of patient data was conducted to identify patients over the age of 60 years with comor- bidities that underwent pretibial soft tissue reconstruction with a single-pedicle perforator flap. Patient demographics, size and cause of the defect, flap dimension, arc of rotation and complications were recorded.
Results: Five patients with an average age of 71.4 years were in- cluded. The arc of rotation was 69 °, all flaps healed. There were two recurrences of osteomyelitis.
Conclusion: Lateral perforators originating from the anterior tib- ial artery or peroneal artery are adequate source vessels for single pedicled perforator flaps even in medically compromised patients. A perforator located proximal to the defect allows limiting the arcof rotation to less than 90 °, which increases the safety of the flap. Patients benefit from a simple procedure without a microvascular anastomosis and a donor site confined to one extremity
Background
Surgical reattachment of the tendon is still the gold standard for ruptures of the distal biceps brachii tendon. Several fixation techniques have been described in the literature, with suture anchors being one of the most common fixation techniques. Currently, there is no data available on how many anchors are required for a safe and stable refixation. In this case report clinical data of a patient with non-simultaneous bilateral distal biceps tendon ruptures treated with a different number of suture anchors for each side (one vs. two) are demonstrated.
Case presentation
A 47-year-old factory worker suffered a rupture of the distal biceps tendon on both arms following two different occasions. The left side was fixed using a single suture anchor, while refixation on the right side was performed with two anchors. The patient was prospectively followed for one year. Functional outcome was assessed using the Andrews Carson Score (ACS), the Oxford Elbow Score (OES), and the Disabilities of Arm, Shoulder and Hand (DASH) Score after six, twelve, 24 and 48 weeks. Furthermore, an isokinetic strength measurement for flexion strength was performed after 24 and 48 weeks. After 48 weeks the patient presented with excellent functional outcome scores and no follow-up complications. During the follow-up period, no differences in the functional scores nor in the isokinetic flexion strength measurement could be detected. Furthermore, no radiological complications (like heterotopic ossifications) could be detected in the postoperative radiographs after one year.
Conclusions
Anatomic reattachment of the distal biceps tendon is a successful operative treatment option for distal biceps tendon ruptures. Suture anchor fixation remains one of the most common techniques, as it allows fast surgery and provides good results with respect to range of motion (ROM) and functional scoring according to the current literature. However, the number of anchors required for a stable fixation remains unclear. As indicated by our presented case, we hypothesize, that there are no significant differences between a one-point or a two-point fixation. In the presented case report, no intraindividual differences between the usage of one versus two suture anchors were evident in the short-term follow-up.
Background
Mesenchymal stem cell (MSC) based-treatments of cartilage injury are promising but impaired by high levels of hypertrophy after chondrogenic induction with several bone morphogenetic protein superfamily members (BMPs). As an alternative, this study investigates the chondrogenic induction of MSCs via adenoviral gene-delivery of the transcription factor SOX9 alone or in combination with other inducers, and comparatively explores the levels of hypertrophy and end stage differentiation in a pellet culture system in vitro.
Methods
First generation adenoviral vectors encoding SOX9, TGFB1 or IGF1 were used alone or in combination to transduce human bone marrow-derived MSCs at 5 x 10\(^2\) infectious particles/cell. Thereafter cells were placed in aggregates and maintained for three weeks in chondrogenic medium. Transgene expression was determined at the protein level (ELISA/Western blot), and aggregates were analysed histologically, immunohistochemically, biochemically and by RT-PCR for chondrogenesis and hypertrophy.
Results
SOX9 cDNA was superior to that encoding TGFB1, the typical gold standard, as an inducer of chondrogenesis in primary MSCs as evidenced by improved lacuna formation, proteoglycan and collagen type II staining, increased levels of GAG synthesis, and expression of mRNAs associated with chondrogenesis. Moreover, SOX9 modified aggregates showed a markedly lower tendency to progress towards hypertrophy, as judged by expression of the hypertrophy markers alkaline phosphatase, and collagen type X at the mRNA and protein levels.
Conclusion
Adenoviral SOX9 gene transfer induces chondrogenic differentiation of human primary MSCs in pellet culture more effectively than TGFB1 gene transfer with lower levels of chondrocyte hypertrophy after 3 weeks of in vitro culture. Such technology might enable the formation of more stable hyaline cartilage repair tissues in vivo.
Objective
This study aimed to compare a state‐of‐the‐art bioelectrical impedance analysis (BIA) device with two‐point Dixon magnetic resonance imaging (MRI) for the quantification of visceral adipose tissue (VAT) as a health‐related risk factor.
Methods
A total of 63 male participants were measured using a 3‐T MRI scanner and a segmental, multifrequency BIA device. MRI generated fat fraction (FF) maps, in which VAT volume, total abdominal adipose tissue volume, and FF of visceral and total abdominal compartments were quantified. BIA estimated body fat mass and VAT area.
Results
Coefficients of determination between abdominal (r\(^{2}\) = 0.75) and visceral compartments (r\(^{2}\) = 0.78) were similar for both groups, but slopes differed by a factor of two. The ratio of visceral to total abdominal FF was increased in older men compared with younger men. This difference was not detected with BIA. MRI and BIA measurements of the total abdominal volume correlated moderately (r\(^{2}\) = 0.31‐0.56), and visceral measurements correlated poorly (r\(^{2}\) = 0.13‐0.44).
Conclusions
Visceral BIA measurements agreed better with MRI measurements of the total abdomen than of the visceral compartment, indicating that BIA visceral fat area assessment cannot differentiate adipose tissue between visceral and abdominal compartments in young and older participants.
The topical application of tranexamic acid (TXA) helps to prevent post-operative blood loss in total joint replacements. Despite these findings, the effects on articular and periarticular tissues remain unclear. Therefore, this in vitro study examined the effects of varying exposure times and concentrations of TXA on proliferation rates, gene expression and differentiation capacity of chondrocytes and human mesenchymal stromal cells (hMSCs), which underwent osteogenic differentiation. Chondrocytes and hMSCs were isolated and multiplied in monolayer cell cultures. Osteogenic differentiation of hMSCs was induced for 21 days using a differentiation medium containing specific growth factors. Cell proliferation was analyzed using ATP assays. Effects of TXA on cell morphology were examined via light microscopy and histological staining, while expression levels of tissue-specific genes were measured using semiquantitative RT-PCR. After treatment with 50 mg/mL of TXA, a decrease in cell proliferation rates was observed. Furthermore, treatment with concentrations of 20 mg/mL of TXA for at least 48 h led to a visible detachment of chondrocytes. TXA treatment with 50 mg/mL for at least 24 h led to a decrease in the expression of specific marker genes in chondrocytes and osteogenically differentiated hMSCs. No significant effects were observed for concentrations beyond 20 mg/mL of TXA combined with exposure times of less than 24 h. This might therefore represent a safe limit for topical application in vivo. Further research regarding in vivo conditions and effects on hMSC functionality are necessary to fully determine the effects of TXA on articular and periarticular tissues.
Tissue-nonspecific alkaline phosphatase (TNAP) is a ubiquitously expressed enzyme that is best known for its role during mineralization processes in bones and skeleton. The enzyme metabolizes phosphate compounds like inorganic pyrophosphate and pyridoxal-5′-phosphate to provide, among others, inorganic phosphate for the mineralization and transportable vitamin B6 molecules. Patients with inherited loss of function mutations in the ALPL gene and consequently altered TNAP activity are suffering from the rare metabolic disease hypophosphatasia (HPP). This systemic disease is mainly characterized by impaired bone and dental mineralization but may also be accompanied by neurological symptoms, like anxiety disorders, seizures, and depression. HPP characteristically affects all ages and shows a wide range of clinical symptoms and disease severity, which results in the classification into different clinical subtypes. This review describes the molecular function of TNAP during the mineralization of bones and teeth, further discusses the current knowledge on the enzyme’s role in the nervous system and in sensory perception. An additional focus is set on the molecular role of TNAP in health and on functional observations reported in common laboratory vertebrate disease models, like rodents and zebrafish.
Hypophosphatasia (HPP) is a rare, inherited, metabolic disease characterized by tissue‐nonspecific alkaline phosphatase deficiency resulting in musculoskeletal and systemic clinical manifestations. This observational study evaluated the effectiveness of enzyme replacement therapy with asfotase alfa on physical function and health‐related quality of life (HRQoL) among adults with pediatric‐onset HPP who received asfotase alfa for 12 months at a single center (ClinicalTrial.gov no.: NCT03418389). Primary outcomes evaluated physical function with the 6‐minute walk test (6MWT), timed up‐and‐go (TUG) test, Short Physical Performance Battery (SPPB), and handheld dynamometry (HHD). Secondary outcome measures included the Lower Extremity Functional Scale (LEFS), pain prevalence/intensity, and pain medication use; HRQoL was evaluated using the 36‐Item Short‐Form Health Survey version 2 (SF‐36v2). Safety data were collected throughout the study. All 14 patients (11 women) had compound heterozygous ALPL gene mutations and ≥1 HPP bone manifestation, including history of ≥1 fracture. Mean (min, max) age was 51 (19 to 78) years. From baseline to 12 months of treatment, median 6MWT distance increased from 267 m to 320 m (n = 13; p = 0.023); median TUG test time improved from 14.4 s to 11.3 s (n = 9; p = 0.008). Specific components of the SPPB also improved significantly: median 4‐m gait speed increased from 0.8 m/s to 1.1 m/s (n = 10; p = 0.007) and median repeated chair‐rise time improved from 22 s to 13 s (n = 9; p = 0.008). LEFS score improved from 24 points to 53 points (n = 10; p = 0.002). Improvements in HHD were not clinically significant. SF‐36v2 Physical Component Score (PCS) improved after 12 months of treatment (n = 9; p = 0.010). Pain level did not change significantly from baseline to 12 months of treatment. There were significant improvements on chair‐rise time and SF‐36v2 PCS by 3 months, and on TUG test time after 6 months. No new safety signals were identified. These results show the real‐world effectiveness of asfotase alfa in improving physical functioning and HRQoL in adults with pediatric‐onset HPP. © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
Revision Arthroplasty Through the Direct Anterior Approach Using an Asymmetric Acetabular Component
(2020)
Despite increasing numbers of primary hip arthroplasties performed through the direct anterior approach (DAA), there is a lack of literature on DAA revision arthroplasty. The present study was performed in order to evaluate outcomes and revision rates after revision through the DAA using an asymmetric acetabular component with optional intra- and extramedullary fixation. In a retrospective cohort study, we analyzed prospectively collected data of 57 patients (61 hips, 43 female, 18 male) who underwent aseptic acetabular component revision through the DAA with the abovementioned implant system between January 2015 and December 2017. The mean follow-up was 40 months (12–56). Survival rates were estimated using the Kaplan–Meier method. All complications were documented and functional outcomes were assessed pre- and postoperatively. Kaplan–Meier analysis revealed an estimated five-year implant survival of 97% (confidence interval CI 87–99%). The estimated five-year survival with revision for any cause was 93% (CI 83–98%). The overall revision rate was 6.6% (n = 4). Two patients had to undergo revision due to periprosthetic infection (3.3%). In one patient, the acetabular component was revised due to aseptic loosening four months postoperatively. Another patient suffered from postoperative iliopsoas impingement and was treated successfully by arthroscopic iliopsoas tenotomy. Two (3.3%) of the revised hips dislocated postoperatively. The mean Harris Hip Score improved from 35 (2–66) preoperatively to 86 (38–100) postoperatively (p < 0.001). The hip joint’s anatomical center of rotation was restored at a high degree of accuracy. Our findings demonstrate that acetabular revision arthroplasty through the DAA using an asymmetric acetabular component with optional intra- and extramedullary fixation is safe and practicable, resulting in good radiographic and clinical midterm results.
Eine retrospektive Studie anhand von Patientenunterlagen zum Blutverlust, Transfusionshäufigkeit und postoperativen Komplikationen bei Knie-Endo-Prothesen mit systemischer Gabe von 500 mg Tranexamsäure kurz vor Eröffnung der Blutleere! 229 Patienten in der Studiengruppe, von denen 9 eine erlaubte Wiederholungsdosis erhalten hatten, wurden verglichen mit 231 Patienten, die keine Tranexamsäure erhalten hatten. 3 Patienten der Studiengruppe gegenüber 14 Patienten der Kontrollgruppe benötigten eine Bluttransfusion. In der Studiengruppe war der niedrigste postoperative Hb bei 71,2% der Patienten 10 g/dl oder höher. In der Kontrollgruppe war es nur bei 49,4% der Patienten der Fall. Durch die Gabe von Tranexamsäure konnte der durchschnittliche, berechnete Blutverlust bei Männern von etwa 1850 ml auf 1450 ml und bei Frauen von etwa 1300 ml auf etwa 1000 ml gesenkt werden. Die Unterschiede waren signifikant! Im beobachteten Kollektiv konnte keine Steigerung der Rate an Thrombosen oder thrombembolischen Ereignissen festgestellt werden. Das Antifibrinolytikum Tranexamsäure ist in dieser niedrigen Dosierung effektiv und scheint sicher zu sein.
Fragestellung: Epidemiologisch zeigt sich seit einigen Jahren ein Anstieg der Fallzahlen von Hüftpannenrevisionen. Zudem gewinnt die Lebensqualität der älter werdenden Bevölkerung zunehmend an Bedeutung. Eine Herausforderung für den behandelnden Chirurgen stellt insbesondere die Versorgung von größeren acetabulären Defekten dar. In dieser Studie wurden klinische und radiologische Ergebnisse von Hüftpfannenrevisionen, die durch ein kranial aufgesockeltes, längsovales Revisionspfannensystem versorgt wurden, untersucht. Ferner sollten mögliche Einflussfaktoren auf das Operationsergebnis ermittelt werden.
Methodik: In einer retrospektiven monozentrischen Studie wurden 155 Patienten, die im Zeitraum von 2009 bis 2016 mit Kranialpfannen versorgt wurden, nachuntersucht und Scores erhoben. Ein Unbedenklichkeitsbescheid der Ethikkommission der Universität Würzburg lag vor.
Ergebnisse: Das Follow-up lag im Durchschnitt bei 53 Monaten. Es wurden 9 AAOS I Defekte, 25 AAOS II Defekte, 100 AAOS III Defekte und 21 AAOS IV-Defekte nachuntersucht. Das kumulative Gesamtüberleben nach Kaplan-Meier betrug für diesen Follow-up Zeitraum 93,4% (CI 89,1-97,6%). Das revisionsfreie Überleben lag bei 84,0% (CI 77,9-90,1%). Es konnte eine signifikante Schmerzreduktion auf einer visuellen Analogskala belegt werden (5,9 präoperativ vs. 1,1 postoperativ). Der Harris-Hip-Score verbesserte sich hochsignifikant von 56,4 präoperativ auf 73,2 postoperativ. Ferner konnte in allen Dimensionen des Euroqols eine signifikante Verbesserung nachgewiesen werden. Der Gesundheitszustand der Patienten wurde anhand des SF-12 bestimmt. Als Ergebnis zeigte sich verglichen mit der Referenzpopulation eine leicht erniedrigte physische Gesundheit und eine geringgradig erhöhte psychische Gesundheit.
Im Rahmen dieser Arbeit konnten einige signifikante Einflussfaktoren auf das Operationsergebnis ermittelt werden: Das männliche Geschlecht ist mit einem signifikant besseren funktionellen Outcome assoziiert (HHS 87,7 vs. 74,2). Zudem gaben Männer auf der visuellen Analogskala eine signifikant geringere Schmerzintensität an (0,65 vs. 1,5). Darüber hinaus konnte belegt werden, dass höhergradige Defekttypen mit einem schlechteren funktionellen Outcome vergesellschaftet sind. Das funktionelle Outcome unterscheidet sich zudem signifikant in Abhängigkeit vom Alter der Patienten zum Zeitpunkt der Operation. Patienten unter 70 Jahren erreichten im Durchschnitt signifikant höhere Punktzahlen im Harris-Hip-Score (82,2 vs. 77,3). Septische Indikationen standen verglichen mit aseptischen Lockerungen ebenfalls in Assoziation mit einem schlechteren funktionellen Outcome (HHS 74,6 vs. 81,9).
Schlussfolgerung: Anhand der im Zuge dieser Arbeit ermittelten Überlebensrate, einer Verbesserung der Funktionalität im Hüftgelenk und einer nachgewiesenen Schmerzreduktion konnten gute kurz- bis mittelfristige Ergebnisse für das vorliegende Implantatsystem gezeigt werden. Als Einflussfaktoren auf das klinische Outcome konnten das Geschlecht, der zugrunde liegende Defekttyp, das Alter zum OP-Zeitpunkt und eine septische oder aseptische Indikation ermittelt werden.
Aufgrund des demographischen Wandels mit einer zunehmend älter werdenden Bevölkerung ist die Zahl der Knieprothesen und vor allem auch der Revisionsoperationen in den letzten Jahren deutlich gestiegen. Mit ebenfalls zunehmendem medizinischem Anspruch wurden die bestehenden Prothesenmodelle stetig weiter entwickelt.
Ziel der vorliegenden Studie war es, in einer prospektiv angelegten einfach verblindeten Studie zwei verschiedene Rotating-Hinge-Revisionsprothesen unterschiedlicher Hersteller miteinander zu vergleichen und sie auf ihr klinisches Outcome zu überprüfen.
Von Juni 2012 bis Mai 2013 wurden insgesamt 25 Patienten in die Studie aufgenommen und dann bis zu 12 Monate nach erfolgter Revisionsoperation nachuntersucht. Die Zuteilung der Prothesenarten erfolgte randomisiert, sodass 13 Patienten die Prothese „EnduRo“ und 12 Patienten die Prothese „Endo-Modell“ erhielten. Als Vergleichswerte wurden klinische Scores herangezogen.
In der Untersuchung zeigten beiden Vergleichsgruppen insgesamt eine deutliche Schmerzreduktion sowie eine Funktionsverbesserungen in allen erhobenen Scores. Zwar erreichten die Patienten der Gruppe „Endo-Modell“ etwas höhere Punktwerte, jedoch waren die Unterschiede im Vergleich zur Patientengruppe „EnduRo“ im durchgeführten Zweistichproben-T-Test nicht statistisch signifikant.
Trotz ständiger Weiterentwicklung der modernen Endoprothetik weist ein künstliches Gelenk auch heute eine begrenzte Haltbarkeit auf. Insbesondere bei der Versorgung jüngerer Patienten mit gestiegener Lebenserwartung wird häufig die Prothesenstandzeit aufgebraucht und ein komplizierter Revisionseingriff notwendig. Hierbei ist die aseptische Prothesenlockerung der häufigste Grund für den Austausch eines Implantates. Das Knochenmark des betreffenden Knochens enthält humane Mesenchymale Stammzellen (hMSC), die zur Aufrechterhaltung und Regeneration des Bindegewebes und des Knochens selbst beitragen. Ob diese Zellen z.B. durch ein Proliferations- oder Differenzierungsdefizit eine Rolle in der Ätiologie einer aseptischen Prothesenlockerung spielen, ist bisher nicht abschließend geklärt.
In der vorliegenden Arbeit wurde die regenerative Kapazität von hMSC von zwei Spendergruppen untersucht und verglichen: Als Wechselgruppe dienten Patienten, bei denen es zu einer aseptischen Prothesenlockerung und der Notwendigkeit eines Revisionseingriffes (Wechseloperation) gekommen war. Patienten, denen primär eine Hüft- oder Kniegelenksendoprothese eingesetzt wurde, bildeten die Kontrollgruppe. Zur Beurteilung der regenerativen Eigenschaften der hMSC wurde zum einen das Wachstums- und Alterungsverhalten in Zellkultur zum anderen die in vitro Differenzierungskapazität untersucht.
Die Knieendoprothetik verzeichnet in den letzten Jahren steigende Zahlen, was wiederum steigende Zahlen an Revisionen zur Folge hat. Diese Studie hat die Gründe für Revisionen ermittelt. Hierzu wurden 1245 Operationen gesammelt und ausgewertet. Instabilität, Infektion und aseptische Lockerungen stellen die Hauptgründe für eine Revisionsoperation dar. Es wurden zusätzlich verschiedene Zeiträume zwischen Primärimplantation und Revision unterteilt und die jeweiligen Gründe ermittelt.
In vorliegender Dissertation wurden die Langzeitergebnisse hinsichtlich der Lebensqualität der Patienten, die sich im Zeitraum 2002-2010 eine proximale Humerusfraktur zuzogen und mittels intramedullärer Drahtosteosynthese nach Kapandji im König Ludwig Haus in Würzburg operiert wurden, untersucht. Die Nachuntersuchung erfolgte mittels klinischer, radiologischer und sonografischer Untersuchung sowie durch Verwendung des DASH-Fragebogens, Constant Murley Score und der Visuellen Analogskala.
Der menschliche Körper besitzt Anpassungsmechanismen, die es ihm ermöglichen, sich an verschiedene Belastungssituationen anzupassen. Es gab in letzter Zeit mehrere Hinweise darauf, dass diese Mechanismen durch die Ausschüttung von Zytokinen, bzw. Myokinen durch die betroffenen Zellen selbst ausgelöst werden. In dieser Arbeit wurden die Serumkonzentration von Myostatin, Follistatin, Follistatin-like-3, Interleukin 6, Interleukin 8 und Klotho vor und nach einer kurzen körperlichen Belastung bestimmt. Dabei konnte allerdings keine signifikante Änderung der Konzentrationen nachgewiesen werden, was die Frage aufwirft, ob mesenchymales Gewebe, insbesondere Muskelgewebe, überhaupt über einen klassischen endokrinen Sekretionsmechanismus verfügt.
Autologous bone still represents today’s gold standard for the treatment of critical size bone defects and fracture non-unions despite associated disadvantages regarding limitations in availability, donor site morbidity, costs and efficacy. Bone tissue engineered constructs would present a promising alternative to currently available treatments. However, research on preclinical animal studies still fails to provide clinical applicable results able to allow the replacement of currently applied methods. It seems that the idea of bone tissue engineering, which has now been integral part of academic studies for over 30 years, got somehow stuck at an intermediate level, in between intense preclinical research and striven stages of initial clinical trial phases. A clear discrepancy exists between the number of studies with preclinical animal models for bone tissue engineering and the number of clinically approved bone tissue engineered constructs available to patients.
The aim of this thesis was hence to evaluate preclinical animal models for bone tissue engineering as well as the perception of scientists and clinicians towards these models. Moreover, the general role of bone tissue engineering and its clinical need assessed by scientists and surgeons was investigated. A survey was conducted questioning both scientific and clinical opinions on currently available study designs and researchers’ satisfaction with preclinical animal models. Additionally, a literature research was conducted, resulting in 167 papers from the last 10 years that report current designs of preclinical orthotopic animal studies in bone tissue engineering. Thereby, the focus lied on the description of the models regarding animal species, strain, age, gender and defect design. The outcome of the literature search was evaluated and compared to the outcome obtained from the survey.
The survey data revealed that both scientists and surgeons generally remain positive about the future role of bone tissue engineering and its step to clinical translation, at least in the distant future, where it then might replace the current gold standard, autologous bone. Moreover, most of the participants considered preclinical animal models as relevant and well developed but the results as not yet realizable in the clinics. Surgeons thereby demonstrated a slightly more optimistic perception of currently conducted research with animal models compared to scientists. However, a rather inconsistent description of present preclinical study designs could be discerned when evaluating the reported study designs in the survey and the papers of the literature search.
Indeed, defining an appropriate animal species, strain, age, gender, observation time, observation method and surgical design often depends on different indications and research questions and represents a highly challenging task for the establishment of a preclinical animal model. The existing lack of valid guidelines for preclinical testing of bone tissue engineering leads hence to a lack of well standardized preclinical animal models. Moreover, still existing knowledge gaps regarding aspects that affect the process of fracture healing, such as vascularization or immunological aspects, were found to hinder clinical translation of bone tissue engineered constructs.
Using literature review and survey, this thesis points out critical issues that need to be addressed to allow clinical translation of bone tissue engineered constructs. It can be concluded that currently existing study designs with preclinical animal models cannot live up to the claim of providing suitable results for clinical implementation. The here presented comprehensive summary of currently used preclinical animal models for bone tissue engineering reveals a missing consensus on the usage of models such as an apparent lack of reporting and standardization regarding the study designs described in both papers from the literature review and the survey. It thereby indicates a crucial need to improve preclinical animal models in order to allow clinical translation. Despite the fact that participants of the survey generally revealed a positive perception towards the use of bone tissue engineered constructs and affirmed the clinical need for such novel designs, the missing standardization constitutes a main weak point for the provision of reliable study outcome and the translational success of the models. The optimization of reproducibility and reliability, as well as the further understanding of ongoing mechanisms in bone healing in order to develop effective tissue engineered constructs, need to form the basis of all study designs. The study outcomes might then fulfill the requirements of maybe today's and hopefully tomorrow's aging population.
Background:
Diese prospektiv randomisierte kontrollierte Single-Center-Studie untersucht das klinische Outcome 3 bis 12 Monate nach Implantation einer Hüfttotalendoprothese über den transglutealen lateralen Hüftzugang (Bauer).
Methods:
77 Patienten wurden in die transgluteale laterale Zugangsweg Kohorte randomisiert, wovon 50 Patienten die Studie beendeten. Alle Patienten wurden mit dem Harris Hip Score (HHS), dem Xtra Short Musculosceletal Functional Assesment Questionaire (XSFMA), dem 36-Item Short Form Survey (SF-36), einem Stepwatch™-Aktivitätsmonitor (SAM) und einem zeitabhängigen 25m-Gehtest bewertet. Mit Hilfe der postoperativen Standard- röntgenaufnahmen wurde die Inklination, Schaftpositionierung und das Offset bewertet.
Results:
Unsere Patienten verbesserten sich nach drei Monaten in Bezug auf den 25-m-Gehtest (prä-operativ 24 Sekunden, SD ± 6,07, 3 Monate 19,36 Sekunden, SD ± 3,80) und die vom Patienten geschätzte maximale Gehstrecke nicht signifikant (präoperativ 1187, SD ± 1809m und 12 Monate 5125m, SD ± 3867m). Mit der Stepwatch konnte ein postoperativer Anstieg der mittleren Gehzyklen pro Tag gemessen werden (präoperativ 4964, SD ± 2687, 3 Monate 5238, SD ± 2309, 12 Monate 5340, SD ± 1887). Der Bewegungsumfang verbesserte sich insbesondere für die Flexion (präoperativ 89°, 3 Monate 97,34°) und die Abduktion (präoperativ 25,31°, 3 Monate 37,45°) und blieb im weiteren Verlauf nahezu unverändert. Der HHS zeigte einen signifikanten Unterschied zwischen dem präoperativen Score (52,95, SD ± 15,69) und den Scores aller postoperativen Messzeitpunkte (3 Monate 88,40, SD ± 9,89, 6 Monate 89,05, SD ± 10,01, 12 Monate 91,43, SD ± 9,05, p <0,001). Gleiches gilt für den XSFMA-Funktionsindex, der sich zwischen dem präoperativen Score (40,50, SD ± 15,78) und den postoperativen Scores signifikant verbesserte (3 Monate 18,80, SD ± 16,12, 6 Monate 15,84, SD ± 15,39, 12 Monate 15,08, SD ± 16,33, p<0.001). Der SF-36-Score mit der Subgruppe der körperlichen Verfassung betrug präoperativ 25,62, SD ± 8,74 und war postoperativ ebenfalls signifikant höher (3 Monate 40,67, SD ± 10,01, 6 Monate 42,76, SD ± 9,59, 12 Monate 42,91, SD ± 11,86, p < 0,05), während der Subscore der psychischen Beurteilung sich stets auf konstantem Niveau befand (präoperativ 56,26, SD ± 9,23, 3 Monate 56,68, SD ± 8,23, 6 Monate 55,81, SD ± 7,22, 12 Monate 56,23, SD ± 6,92, p <0,05). Die Bewertung der postoperativen Röntgenbildgebung ergab eine durchschnittliche Pfanneninklination von 40,28 ° und einen femorales Offset von 38,1mm ohne Anzeichen von Migration.
Conclusion:
Zusammenfassend zeigen unsere Ergebnisse, dass sich bereits drei Monate nach Implantation einer Totalhüftendoprothese über den transglutealen lateralen Zugang die Lebensqualität, das Aktivitätsniveau, die Patientenzufriedenheit und der postoperative Bewegungsumfang signifikant verbessert haben.
Trial registration:
DRKS00014808 (German Clinical Trial Register DRKS); date of registration: 31.05.2018.
Wirkung von WISP-3 auf dedifferenzierte Chondrozyten und mesenchymale Stammzellen
Degenerative Gelenkerkrankungen (Arthrosen) sind einige der häufigsten Ursachen für eine Vorstellung und Beratung in der allgemeinmedizinischen Praxis. Der Großteil der über 65-jährigen ist davon betroffen, wenn auch die Symptome in ihrer Ausprägung stark variieren können. Eine ursächliche Therapie ist bisher nicht bekannt. Es wird symptomatisch behandelt und versucht, die Symptome zu lindern und den Progress der Erkrankung zu verlangsamen. Dabei entstehen dem Gesundheitssystem durch die hohe Prävalenz nicht unerhebliche Kosten für Medikamente, Physiotherapie, Operationen und Reha-Aufenthalte.
Arthrosen beruhen auf Knorpelschädigungen, die ohne Therapie immer weiter fortschreiten können und zu Schmerzen, Bewegungseinschränkung und Verformung des Gelenks führen können. Diese Knorpelschädigungen können auf verschiedenen Ursachen beruhen wie z.B. zu hoher Belastung (bei Adipositas), Traumata oder Erkrankungen des Skelettsystems. Neue Behandlungsansätze werden mit zunehmendem Durchschnittsalter der Bevölkerung immer wichtiger werden.
Ein Ansatzpunkt ist die weitere Erforschung von Proteinen wie z.B. WISP-3, die einen positiven Effekt auf die Knorpelhomöostase bewirken. Die Bedeutung von WISP-3 fiel bei der Erforschung der Progressiven Pseudorheumatoiden Dysplasie auf, einer seltenen Gelenkerkrankung, die v.a. bei Kindern auftritt. Dabei treten auf Grund von Mutationen von WISP-3 Störungen in der Knorpelhomöostase und Gelenkarchitektur auf, die sogar eine Therapie mittels Gelenkersatz notwendig machen können.
In unseren Versuchen zeigte sich, dass WISP-3 in Verbindung mit Wachstumsfaktoren eine positive Wirkung auf das Wachstum und die Differenzierung von dedifferenzierten Chondrozyten aufweist. Somit werden neue Forschungsansätze in der Arthrosetherapie aufgezeigt. Für die weitere Forschung kann auch auf mesenchymale Stammzellen zurückgegriffen werden, die vielversprechende Aussichten besonders im Tissue Engineering bieten.
Für die gesamte CCN-Familie ergeben sich noch weitere vielfältige Forschungsmöglichkeiten, wie z.B. in der Therapie von Mamma-, Gebärmutter- oder Nierenzellkarzinomen.
Erstellung und Auswertung einer Tumordatenbank in der Orthopädischen Klinik König-Ludwig-Haus
(2020)
Die vorliegende Arbeit befasst sich mit der Analyse eines Patientenkollektivs von 771 Tumorpatienten, welche im Zeitraum von September 2009 bis 31.12.2014 im interdisziplinären muskuloskelettalen Tumorboard des Comprehensive Cancer Center Mainfranken der Universitätsklinik Würzburg vorgestellt wurden. Es wurde eine retrospektive Betrachtung dieser Patienten durchgeführt, um das behandelte Patientenkollektiv zu typisieren und einen Überblick über Art und Anzahl der betreuten Patienten zu erhalten.
Osteozyten stehen vermehrt im Fokus als wesentliche Regulatoren der Knochenmineralisierung. Das ähnlich einem neuronalen Netzwerk aufgebaute lakunokanalikuläre Netzwerk der Osteozyten breitet sich im Knochen in drei Ebenen aus. Es wurde in dieser Arbeit ein 3D-Kollagengel-Modell verwendet und dort die Osteoblasten- bzw. Osteozytenzelllinien MLO-A5 und MLO-Y4, sowie humane mesenchymale Stammzellen aus Hüftköpfen eingebettet. Es wurden die optimalen Kulturbedingungen entwickelt und die Zellen über mehrere Wochen kultiviert, beobachtet und mit dem herkömmlichen 2D-Kulturmodell verglichen. MLO-A5 und MLO-Y4 bilden die zelltypischen Zellfortsätze. Die Gele kontrahieren, wenn hMSC und MLO-A5 eingebettet sind, mit MLO-Y4 zeigt sich über den gesamten Kultivierungszeitraum keinerlei Kontraktion der Kollagengele. Die Zellen wurden zudem osteogen differenziert und mit FGF23 und Klotho stimuliert. Es ergaben sich erste Hinweise auf eine FGF23 / Klotho-abhängige Inhibierung der lokalen Mineralisierung in osteogen differenzierten MLO-A5.
Es konnten einige osteogene Marker durch PCR und in den histologischen Schnitten mittels Antikörperfärbungen nachgewiesen werden, eindeutige Expressionsmuster und deren zeitliche Verläufe im Vergleich der osteogenen Differenzierungen und Zugabe von FGF23 und Klotho sind allerdings noch nicht identifizierbar und bedürfen womöglich höherer Fallzahlen und weiterer Untersuchungsmethoden. Insgesamt gesehen erweist sich das System aber als einfach und mit niederschwellig erreichbaren Methoden und Materialien durchzuführen.