Development of a Force-Driven Distractor for Distraction Osteogenesis

2011 ◽  
Vol 5 (4) ◽  
Author(s):  
Jinyong Wee ◽  
Robert E. Akins ◽  
William G. Mackenzie ◽  
Rahamim Seliktar ◽  
David G. Levine ◽  
...  
Keyword(s):  
Distraction Osteogenesis ◽  
Limb Lengthening ◽  
Load Cell ◽  
Long Bone ◽  
Data Logger ◽  
Tissue Integrity ◽  
Tibial Lengthening ◽  
Cell Data ◽  
Distraction Rate

Distraction osteogenesis is a routine surgical procedure to lengthen a long bone. A fixed lengthening rate is typically used. We investigate measuring forces continuously and producing a variable distraction rate. A motorized distractor was instrumented with a load cell to measure the forces developed in a limb during distraction osteogenesis. The motor moves 2.6 μm at each step, with a variable frequency depending on the distraction rate. The forces were measured every 15 s and used to change the rate on the autodistractor. The autodistractor, load cell, data logger, controller, and battery pack were all mounted on a monolateral rail fixator, which was tested on a sheep that underwent tibial lengthening. Results show the feasibility of continually recording forces in vivo. The lengthening rate changed automatically, based around a threshold force of 300 N. Findings indicate that force readings are feasible and practical with a simple device. Force determination may provide an additional means to evaluate tissue integrity in real-time and away from the clinic. An automatic variable rate device could improve limb lengthening.

Growth factors of the TGF-b family in blood of achondroplasia patients at stages of orthopedic treatment

2018 ◽  
pp. 70-76
Author(s):  
Е.П. Выхованец ◽  
Н.В. Сакулин ◽  
С.Н. Лунева ◽  
Н.В. Накоскина ◽  
О.В. Климов
Keyword(s):  
Growth Factors ◽  
Limb Lengthening ◽  
Serum Levels ◽  
Long Bone ◽  
Ilizarov Method ◽  
Bone Lengthening ◽  
Serum Concentrations ◽  
Orthopedic Treatment ◽  
Tibial Lengthening ◽  
Height Increase

Наиболее важной задачей при дистракционном остеосинтезе является создание простых и эффективных способов контроля темпов дистракции позволяющих производить удлинение конечности в оптимальном режиме у различных групп пациентов. Цель исследования - анализ содержания сывороточных концентраций TGFb-1 и TGFb-2, BMP-4 и BMP-6 у лиц при увеличении роста с косметической целью и у пациентов с ахондроплазией на этапах дистракционного остеогенеза при удлинении голени методом Илизарова. Методика. Определение ростовых факторов проводили на комплексе оборудования фирмы Thermofisher (США): детектор Multiscan FC, встряхиватель iEMS, автоматический промыватель планшет WellWash. Для измерения концентрации факторов в сыворотке крови использовали наборы для иммуноферментного анализа (ИФА) eBioscience и RayBiotech Inc. (США). Результаты . Показано, что в сыворотке крови людей с ахондроплазией, еще до какого-либо ортопедического лечения концентрации TGF-b2 и ВМР-4, ниже, а TGF-b1 и ВМР-6, выше, чем концентрации этих факторов у людей при увеличении роста с косметической целью. У последних удлинение конечностей сопровождается возрастанием содержания в сыворотке крови факторов TGF-b1 и TGF-b2 на этапах начала и середины процесса дистракции. У пациентов с ахондроплазией, наблюдается обратная динамика: концентрация данных факторов (ВМР-4 и ВМР-3) в крови ахондропатов к концу дистракции увеличивается в 3,5 и 2 раза соответственно, снижаясь в периоде фиксации. Заключение. Таким образом, у пациентов с ахондроплазией происходит нарушение этапности процессов костного ремоделирования. Elaboration of simple and effective ways for managing the distraction rate to provide an optimum regimen of limb lengthening for different groups of patients is an important task in implementation of transosseous osteosynthesis. The aim of this study was to analyze blood serum concentrations of TGFb-1, TGFb-2, BMP-4, and BMP-6 in individuals undergoing cosmetic height increase and patients with achondroplasia at different stages of distraction osteogenesis in tibial lengthening using the Ilizarov method. Methods. Concentrations of growth factors were measured using a set of Thermofisher (USA) equipment, including a Multiscan FC detector, iEMS Shaker, and automatic WellWash Washer and ELISA kits (eBioscience and RayBiotech Inc., USA). Results. Serum concentrations of TGFb-2 and BMP-4 were lower and TGFb-1 and BMP-6 were higher in achondroplasia patients than in individuals with cosmetic height increase even before any orthopedic treatment. Long bone lengthening for cosmetic height increase was associated with increases in serum levels of TGFb-1 and TGFb-2 at the start and in the middle of distraction. In achondroplasia patients, opposite changes were observed; serum concentrations of BMP-4 and BMP-3 increased 3.5 and 2 times, respectively, by the end of distraction and decreased during fixation. Conclusion. Therefore, we observed a disorder of the stage-by-stage bone remodeling process in achondroplasia patients.

Facial Nerve Dysfunction After Mandibular Distraction Osteogenesis in Patients with Robin Sequence: A Systematic Review and Meta-Analysis

2022 ◽  
pp. 105566562110707
Author(s):  
Elina Kapoor ◽  
Esperanza Mantilla-Rivas ◽  
Md Sohel Rana ◽  
Marudeen Aivaz ◽  
Daniela Duarte-Bateman ◽  
...  
Keyword(s):  
Systematic Review ◽  
Facial Nerve ◽  
Distraction Osteogenesis ◽  
Meta Analysis ◽  
Mandibular Distraction ◽  
Robin Sequence ◽  
Published Evidence ◽  
Mandibular Distraction Osteogenesis ◽  
Nerve Dysfunction ◽  
Distraction Rate

Objective Robin Sequence (RS), characterized by micrognathia, glossoptosis, and upper airway obstruction, is an increasingly recognized diagnosis. An effective surgical intervention is mandibular distraction osteogenesis (MDO). This study analyzes published evidence regarding facial nerve dysfunction (FND) associated with MDO. Design and Setting According to PRISMA guidelines, a systematic review was carried out with databases queried in June 2019 using MESH terms, or equivalent terms, as follows: “distraction osteogenesis” and “Robin Sequence”. A review of original Spanish and English articles, were included. Outcome measures included the prevalence of FND; the affected branches; the rate of permanent vs. transient FND; the use of an internal vs. external device; the daily distraction rate; and finally, the overall distraction length. Subsequently, a meta-analysis was conducted to collate results regarding the prevalence of FND and the factors associated with it. Results Of 239 unique studies identified, 19 studies with 729 patients met inclusion criteria; 52 patients developed FND after MDO. A random-effects meta-analysis yielded a pooled prevalence of FND of 6.40%, with moderately heterogeneous studies (I2 = 41%, τ2 = 0.006). Marginal mandibular nerve involvement was most commonly noted. Nine studies reported transient FND, six permanent, one both, and two unspecified. Internal distractors were used in 8 studies and external in 3 and both in 2. Distraction rate was 1.00 to 2.00 mm/day and total distraction length ranged from 13.00 to 22.3 mm. Sample size was the only parameter inversely associated with rate of FND (p = 0.04). Conclusion This analysis of FND associated with MDO for patients with RS demonstrates a lack of consistent documentation. MDO-associated FND does not appear to be uncommon, and permanent dysfunction can occur. This review underscores the importance of thorough documentation to elucidate the mechanism of FND.

scholarly journals Biocompatibility and Bone Formation of Flexible, Cotton Wool-like PLGA/Calcium Phosphate Nanocomposites in Sheep

2011 ◽  
Vol 5 (1) ◽  
pp. 63-71 ◽  
Author(s):  
Oliver D Schneider ◽  
Dirk Mohn ◽  
Roland Fuhrer ◽  
Karina Klein ◽  
Käthi Kämpf ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Bone Formation ◽  
Antimicrobial Properties ◽  
Drill Hole ◽  
Bone Defects ◽  
Long Bone ◽  
Minimal Amount ◽  
Cotton Wool

Background: The purpose of this preliminary study was to assess the in vivo performance of synthetic, cotton wool-like nanocomposites consisting of a biodegradable poly(lactide-co-glycolide) fibrous matrix and containing either calcium phosphate nanoparticles (PLGA/CaP 60:40) or silver doped CaP nanoparticles (PLGA/Ag-CaP 60:40). Besides its extraordinary in vitro bioactivity the latter biomaterial (0.4 wt% total silver concentration) provides additional antimicrobial properties for treating bone defects exposed to microorganisms. Materials and Methods: Both flexible artificial bone substitutes were implanted into totally 16 epiphyseal and metaphyseal drill hole defects of long bone in sheep and followed for 8 weeks. Histological and histomorphological analyses were conducted to evaluate the biocompatibility and bone formation applying a score system. The influence of silver on the in vivo performance was further investigated. Results: Semi-quantitative evaluation of histology sections showed for both implant materials an excellent biocompatibility and bone healing with no resorption in the adjacent bone. No signs of inflammation were detectable, either macroscopically or microscopically, as was evident in 5 µm plastic sections by the minimal amount of inflammatory cells. The fibrous biomaterials enabled bone formation directly in the centre of the former defect. The area fraction of new bone formation as determined histomorphometrically after 8 weeks implantation was very similar with 20.5 ± 11.2 % and 22.5 ± 9.2 % for PLGA/CaP and PLGA/Ag-CaP, respectively. Conclusions: The cotton wool-like bone substitute material is easily applicable, biocompatible and might be beneficial in minimal invasive surgery for treating bone defects.

scholarly journals Open Source Digitally Replicable Lab-Grade Scales

2020 ◽  
Author(s):  
Benjamin R. Hubbard ◽  
Joshua M. Pearce
Keyword(s):  
Open Source ◽  
Low Cost ◽  
Cost Savings ◽  
Load Cell ◽  
Significant Cost ◽  
Load Cells ◽  
The Cost ◽  
Cell Data ◽  
Precision Balance ◽  
Multiple Load

This study provides designs for a low-cost, easily replicable open source lab-grade digital scale that can be used as a precision balance. The design is such that it can be manufactured for use in most labs throughout the world with open source RepRap-class material extrusion-based 3-D printers for the mechanical components and readily available open source electronics including the Arduino Nano. Several versions of the design were fabricated and tested for precision and accuracy for a range of load cells. The results showed the open source scale was found to be repeatable within 0.1g with multiple load cells, with even better precision (0.01g) depending on load cell range and style. The scale tracks linearly with proprietary lab-grade scales, meeting the performance specified in the load cell data sheets, indicating that it is accurate across the range of the load cell installed. The smallest loadcell tested(100g) offers precision on the order of a commercial digital mass balance. The scale can be produced at significant cost savings compared to scales of comparable range and precision when serial capability is present. The cost savings increase significantly as the range of the scale increases and are particularly well-suited for resource-constrained medical and scientific facilities.

scholarly journals Single cell RNA sequencing of calvarial and long bone endocortical cells

2019 ◽  
Author(s):  
Ugur M. Ayturk ◽  
Joseph P. Scollan ◽  
Alexander Vesprey ◽  
Christina M. Jacobsen ◽  
Paola Divieti Pajevic ◽  
...  
Keyword(s):  
Gene Expression ◽  
Single Cell ◽  
Cultured Cells ◽  
Neutralizing Antibody ◽  
Long Bone ◽  
Appendicular Skeleton ◽  
Rna Seq ◽  
Isolated Cells

ABSTRACTSingle cell RNA-seq (scRNA-seq) is emerging as a powerful technology to examine transcriptomes of individual cells. We determined whether scRNA-seq could be used to detect the effect of environmental and pharmacologic perturbations on osteoblasts. We began with a commonly used in vitro system in which freshly isolated neonatal mouse calvarial cells are expanded and induced to produce a mineralized matrix. We used scRNA-seq to compare the relative cell type abundances and the transcriptomes of freshly isolated cells to those that had been cultured for 12 days in vitro. We observed that the percentage of macrophage-like cells increased from 6% in freshly isolated calvarial cells to 34% in cultured cells. We also found that Bglap transcripts were abundant in freshly isolated osteoblasts but nearly undetectable in the cultured calvarial cells. Thus, scRNA-seq revealed significant differences between heterogeneity of cells in vivo and in vitro. We next performed scRNA-seq on freshly recovered long bone endocortical cells from mice that received either vehicle or Sclerostin-neutralizing antibody for 1 week. Bone anabolism-associated transcripts were also not significantly increased in immature and mature osteoblasts recovered from Sclerostin-neutralizing antibody treated mice; this is likely a consequence of being underpowered to detect modest changes in gene expression, since only 7% of the sequenced endocortical cells were osteoblasts, and a limited portion of their transcriptomes were sampled. We conclude that scRNA-seq can detect changes in cell abundance, identity, and gene expression in skeletally derived cells. In order to detect modest changes in osteoblast gene expression at the single cell level in the appendicular skeleton, larger numbers of osteoblasts from endocortical bone are required.

scholarly journals Rac signaling in osteoblastic cells is required for normal bone development but is dispensable for hematopoietic development

Blood ◽  
2012 ◽  
Vol 119 (3) ◽  
pp. 736-744 ◽  
Author(s):  
Steven W. Lane ◽  
Serena De Vita ◽  
Kylie A. Alexander ◽  
Ruchan Karaman ◽  
Michael D. Milsom ◽  
...  
Keyword(s):  
Bone Growth ◽  
Bone Development ◽  
Long Bone ◽  
Perivascular Niche ◽  
Hematopoietic Stem ◽  
Hsc Niche ◽  
Rac1 Gtpase

Abstract Hematopoietic stem cells (HSCs) interact with osteoblastic, stromal, and vascular components of the BM hematopoietic microenvironment (HM) that are required for the maintenance of long-term self-renewal in vivo. Osteoblasts have been reported to be a critical cell type making up the HSC niche in vivo. Rac1 GTPase has been implicated in adhesion, spreading, and differentiation of osteoblast cell lines and is critical for HSC engraftment and retention. Recent data suggest a differential role of GTPases in endosteal/osteoblastic versus perivascular niche function. However, whether Rac signaling pathways are also necessary in the cell-extrinsic control of HSC function within the HM has not been examined. In the present study, genetic and inducible models of Rac deletion were used to demonstrate that Rac depletion causes impaired proliferation and induction of apoptosis in the OP9 cell line and in primary BM stromal cells. Deletion of Rac proteins caused reduced trabecular and cortical long bone growth in vivo. Surprisingly, HSC function and maintenance of hematopoiesis in vivo was preserved despite these substantial cell-extrinsic changes. These data have implications for therapeutic strategies to target Rac signaling in HSC mobilization and in the treatment of leukemia and provide clarification to our evolving concepts of HSC-HM interactions.

scholarly journals Alendronate Can Improve Bone Alterations in Experimental Diabetes by Preventing Antiosteogenic, Antichondrogenic, and Proadipocytic Effects of AGEs on Bone Marrow Progenitor Cells

2016 ◽  
Vol 2016 ◽  
pp. 1-13 ◽  
Author(s):  
Sara Rocío Chuguransky ◽  
Ana María Cortizo ◽  
Antonio Desmond McCarthy
Keyword(s):  
Bone Marrow ◽  
Experimental Diabetes ◽  
Bone Microarchitecture ◽  
Bone Matrix ◽  
Diabetic Rats ◽  
Long Bone ◽  
Osteogenic Potential ◽  
Bone Marrow Progenitor

Bisphosphonates such as alendronate are antiosteoporotic drugs that inhibit the activity of bone-resorbing osteoclasts and secondarily promote osteoblastic function. Diabetes increases bone-matrix-associated advanced glycation end products (AGEs) that impair bone marrow progenitor cell (BMPC) osteogenic potential and decrease bone quality. Here we investigated the in vitro effect of alendronate and/or AGEs on the osteoblastogenic, adipogenic, and chondrogenic potential of BMPC isolated from nondiabetic untreated rats. We also evaluated the in vivo effect of alendronate (administered orally to rats with insulin-deficient Diabetes) on long-bone microarchitecture and BMPC multilineage potential. In vitro, the osteogenesis (Runx2, alkaline phosphatase, type 1 collagen, and mineralization) and chondrogenesis (glycosaminoglycan production) of BMPC were both decreased by AGEs, while coincubation with alendronate prevented these effects. The adipogenesis of BMPC (PPARγ, intracellular triglycerides, and lipase) was increased by AGEs, and this was prevented by coincubation with alendronate. In vivo, experimental Diabetes (a) decreased femoral trabecular bone area, osteocyte density, and osteoclastic TRAP activity; (b) increased bone marrow adiposity; and (c) deregulated BMPC phenotypic potential (increasing adipogenesis and decreasing osteogenesis and chondrogenesis). Orally administered alendronate prevented all these Diabetes-induced effects on bone. Thus, alendronate could improve bone alterations in diabetic rats by preventing the antiosteogenic, antichondrogenic, and proadipocytic effects of AGEs on BMPC.

scholarly journals Automated Segmentation and Object Classification of CT Images: Application toIn VivoMolecular Imaging of Avian Embryos

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Alexander Heidrich ◽  
Jana Schmidt ◽  
Johannes Zimmermann ◽  
Hans Peter Saluz
Keyword(s):  
Image Analysis ◽  
Image Segmentation ◽  
Bone Growth ◽  
Imaging Techniques ◽  
Long Bone ◽  
Automated Segmentation ◽  
Chick Embryos ◽  
In Ovo

Background. Although chick embryogenesis has been studied extensively, there has been growing interest in the investigation of skeletogenesis. In addition to improved poultry health and minimized economic loss, a greater understanding of skeletal abnormalities can also have implications for human medicine. Truein vivostudies require noninvasive imaging techniques such as high-resolution microCT. However, the manual analysis of acquired images is both time consuming and subjective.Methods. We have developed a system for automated image segmentation that entails object-based image analysis followed by the classification of the extracted image objects. For image segmentation, a rule set was developed using Definiens image analysis software. The classification engine was implemented using the WEKA machine learning tool.Results. Our system reduces analysis time and observer bias while maintaining high accuracy. Applying the system to the quantification of long bone growth has allowed us to present the first truein ovodata for bone length growth recorded in the same chick embryos.Conclusions. The procedures developed represent an innovative approach for the automated segmentation, classification, quantification, and visualization of microCT images. MicroCT offers the possibility of performing longitudinal studies and thereby provides unique insights into the morpho- and embryogenesis of live chick embryos.

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