I13-2-Diamond Manchester Imaging
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Jishizhan
Chen
,
Alissa
Parmenter
,
Aikta
Sharma
,
Elis
Newham
,
Eral
Bele
,
Sebastian
Marussi
,
Andrew A.
Pitsillides
,
Nick J.
Terrill
,
Christopher
Mitchell
,
Himadri S.
Gupta
,
Peter
Lee
Diamond Proposal Number(s):
[29784]
Open Access
Abstract: Lower back pain is linked to vertebral biomechanics, with vertebral endplates (VEPs) playing a key role. Finite element modelling (FEM) is a powerful tool for studying VEP biomechanics but relies on accurate material property inputs, which remain difficult to obtain. Synchrotron computed tomography (sCT) enables detailed visualisation of intact VEP microstructure under near-physiological loads in situ, with three-dimensional strain fields obtained by digital volume correlation (DVC) providing experimental reference data for FEM validation. We applied inverse finite element methodologies to estimate of the elastic properties of rat VEPs by integrating DVC data into an image-based FE model. Our pipeline estimated an elastic modulus of 129 MPa and a Poisson’s ratio of 0.24 in a rat lumbar segment. The first-order Wasserstein distance between FEM and DVC strain distributions ranged from 0.08% to 0.28%, with Bland–Altman analysis revealing <95% spatial agreement between FEM-predicted and DVC-derived strains across multiple loading steps. Pipeline measurement consistency was evaluated across multiple rat lumbar FE models (n = 3), yielding an estimated VEP elastic modulus = 153 ± 21 MPa and a Poisson’s ratio = 0.28 ± 0.03. Regional variations of strain distribution in VEP bodies and protrusions were also identified (strain Wasserstein distance of 0.10%–0.48%). Our work demonstrates the efficacy of the established pipeline in estimating the isotropic elastic modulus and Poisson’s ratio of VEPs using FEMs in a physiologically relevant, complex load transfer system. As sCT data becomes available, our pipeline lays the foundations for estimating VEP properties in larger animals and humans.
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Mar 2026
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DIAD-Dual Imaging and Diffraction Beamline
I13-2-Diamond Manchester Imaging
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Alissa
Parmenter
,
Elis
Newham
,
Aikta
Sharma
,
Catherine M.
Disney
,
Hans
Deyhle
,
Federico
Bosi
,
Nick J.
Terrill
,
Brian K.
Bay
,
Andrew A.
Pitsillides
,
Himadri S.
Gupta
,
Peter
Lee
Diamond Proposal Number(s):
[29633, 29784]
Open Access
Abstract: The function of all musculoskeletal joints depends on hierarchical structures spanning the molecular to whole-joint scales. Investigating biomechanics across length scales requires correlative multiscale experimental methods. This study applies multimodal in situ synchrotron imaging techniques to spinal joints—focusing on the vertebral endplates—to explore relationships between structure and mechanical strain across spatial scales. Strain mapping using digital volume correlation combined with microarchitectural analysis reveals that high tensile and shear strains play a role in the cartilage to bone transition. Correlative imaging and diffraction show that bone contains narrower mineral nanocrystallites under greater compressive prestrain compared with calcified cartilage. We hypothesize that this multiscale structural adaptation supports the mechanical function of the intervertebral disc. Future applications of the techniques presented here have potential to help unravel the biomechanical underpinnings of pathologies affecting mineralized tissue structure. The multiscale structure-function relationships uncovered here may inspire the design of biomaterials and orthopedic implants.
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Jul 2025
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I13-2-Diamond Manchester Imaging
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Sara
Ajami
,
Zoe
Van Den Dam
,
Julia
Hut
,
Dawn
Savery
,
Milton
Chin
,
Maarten
Koudstaal
,
Miranda
Steacy
,
Alessandra
Carriero
,
Andrew
Pitsillides
,
Yu-Mei
Chang
,
Christoph
Rau
,
Shashidhara
Marathe
,
David
Dunaway
,
Noor Ul Owase
Jeelani
,
Silvia
Schievano
,
Erwin
Pauws
,
Alessandro
Borghi
Diamond Proposal Number(s):
[25386, 29093]
Open Access
Abstract: Crouzon syndrome is a congenital craniofacial disorder caused by mutations in the Fibroblast Growth Factor Receptor 2 (FGFR2). It is characterized by the premature fusion of cranial sutures, leading to a brachycephalic head shape, and midfacial hypoplasia. The aim of this study was to investigate the effect of the FGFR2 mutation on the microarchitecture of cranial bones at different stages of postnatal skull development, using the FGFR2C342Y mouse model. Apart from craniosynostosis, this model shows cranial bone abnormalities. High-resolution synchrotron microtomography images of the frontal and parietal bone were acquired for both FGFR2C342Y/+ (Crouzon, heterozygous mutant) and FGFR2+/+ (control, wild-type) mice at five ages (postnatal days 1, 3, 7, 14 and 21, n = 6 each). Morphometric measurements were determined for cortical bone porosity: osteocyte lacunae and canals. General linear model to assess the effect of age, anatomical location and genotype was carried out for each morphometric measurement. Histological analysis was performed to validate the findings. In both groups (Crouzon and wild-type), statistical difference in bone volume fraction, average canal volume, lacunar number density, lacunar volume density and canal volume density was found at most age points, with the frontal bone generally showing higher porosity and fewer lacunae. Frontal bone showed differences between the Crouzon and wild-type groups in terms of lacunar morphometry (average lacunar volume, lacunar number density and lacunar volume density) with larger, less dense lacunae around the postnatal age of P7–P14. Histological analysis of bone showed marked differences in frontal bone only. These findings provide a better understanding of the pathogenesis of Crouzon syndrome and will contribute to computational models that predict postoperative changes with the aim to improve surgical outcome.
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Aug 2024
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I13-2-Diamond Manchester Imaging
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Diamond Proposal Number(s):
[19322]
Open Access
Abstract: Many soft tissues, such as the intervertebral disc (IVD), have a hierarchical fibrous composite structure which suffers from regional damage. We hypothesise that these tissue regions have distinct, inherent fibre structure and structural response upon loading. Here we used synchrotron computed tomography (sCT) to resolve collagen fibre bundles (∼5μm width) in 3D throughout an intact native rat lumbar IVD under increasing compressive load. Using intact samples meant that tissue boundaries (such as endplate-disc or nucleus-annulus) and residual strain were preserved; this is vital for characterising both the inherent structure and structural changes upon loading in tissue regions functioning in a near-native environment. Nano-scale displacement measurements along >10,000 individual fibres were tracked, and fibre orientation, curvature and strain changes were compared between the posterior-lateral region and the anterior region. These methods can be widely applied to other soft tissues, to identify fibre structures which cause tissue regions to be more susceptible to injury and degeneration. Our results demonstrate for the first time that highly-localised changes in fibre orientation, curvature and strain indicate differences in regional strain transfer and mechanical function (e.g. tissue compliance). This included decreased fibre reorientation at higher loads, specific tissue morphology which reduced capacity for flexibility and high strain at the disc-endplate boundary.
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Oct 2021
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I13-2-Diamond Manchester Imaging
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Diamond Proposal Number(s):
[13237, 11076, 5003]
Abstract: Imaging techniques for quantifying changes in the hierarchical structure of deforming joints are constrained by destructive sample treatments, sample-size restrictions and lengthy scan times. Here, we report the use of fast low-dose pink-beam synchrotron X-ray tomography in combination with mechanical loading at nanometric precision for in situ imaging, at resolutions below 100 nm, of the mechanical strain in intact untreated joints under physiologically realistic conditions. We show that in young, older and osteoarthritic mice, hierarchical changes in tissue structure and mechanical behaviour can be simultaneously visualized, and that the tissue structure at the cellular level correlates with the mechanical performance of the whole joint. We also use the tomographic approach to study the colocalization of tissue strains to specific chondrocyte lacunar organizations within intact loaded joints and to explore the role of calcified-cartilage stiffness on the biomechanics of healthy and pathological joints.
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Nov 2019
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I13-2-Diamond Manchester Imaging
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Diamond Proposal Number(s):
[13237, 11076, 5003]
Open Access
Abstract: The epiphyseal growth plate is a developmental region responsible for linear bone growth, in which chondrocytes undertake a tightly regulated series of biological processes. Concomitant with the cessation of growth and sexual maturation, the human growth plate undergoes progressive narrowing, and ultimately disappears. Despite the crucial role of this growth plate fusion “bridging” event, the precise mechanisms by which it is governed are complex and yet to be established. Progress is hindered by the current methods for growth plate visualization; these are invasive and largely rely on histological procedures. Here, we describe our non-invasive method utilizing synchrotron X-ray computed microtomography for the examination of growth plate bridging, which ultimately leads to its closure coincident with termination of further longitudinal bone growth. We then apply this method to a dataset obtained from a benchtop micro computed tomography scanner to highlight its potential for wide usage. Furthermore, we conduct finite element modeling at the micron-scale to reveal the effects of growth plate bridging on local tissue mechanics. Employment of these 3D analyses of growth plate bone bridging is likely to advance our understanding of the physiological mechanisms that control growth plate fusion.
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Jan 2018
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I22-Small angle scattering & Diffraction
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Blandine
Poulet
,
Ke
Liu
,
Darren
Plumb
,
Phoung
Vo
,
Mittal
Shah
,
Katherine
Staines
,
Alexandra
Sampson
,
Hiroyuki
Nakamura
,
Hideaki
Nagase
,
Alessandra
Carriero
,
Sandra
Shefelbine
,
Andrew A.
Pitsillides
,
George
Bou-Gharios
Open Access
Abstract: Bone development and length relies on the growth plate formation, which is dependent on degradative enzymes such as MMPs. Indeed, deletion of specific members of this enzyme family in mice results in important joint and bone abnormalities, suggesting a role in skeletal development. As such, the control of MMP activity is vital in the complex process of bone formation and growth. We generated a transgenic mouse line to overexpress TIMP3 in mouse chondrocytes using the Col2a1-chondrocyte promoter. This overexpression in cartilage resulted in a transient shortening of growth plate in homozygote mice but bone length was restored at eight weeks of age. However, tibial bone structure and mechanical properties remained compromised. Despite no transgene expression in adult osteoblasts from transgenic mice in vitro, their differentiation capacity was decreased. Neonates, however, did show transgene expression in a subset of bone cells. Our data demonstrate for the first time that transgene function persists in the chondro-osseous lineage continuum and exert influence upon bone quantity and quality.
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Dec 2016
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I13-2-Diamond Manchester Imaging
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K. A.
Staines
,
K.
Madi
,
S. M.
Mirczuk
,
S.
Parker
,
A.
Burleigh
,
B.
Poulet
,
M.
Hopkinson
,
A. J.
Bodey
,
R. C.
Fowkes
,
C.
Farquharson
,
P. D.
Lee
,
A. A.
Pitsillides
Open Access
Abstract: Objective: To explore whether aberrant transient chondrocyte behaviors occur in the joints of STR/Ort mice (which spontaneously develop osteoarthritis [OA]) and whether they are attributable to an endochondral growth defect. Methods: Knee joints from STR/Ort mice with advanced OA and age-matched CBA (control) mice were examined by Affymetrix microarray profiling, multiplex polymerase chain reaction (PCR) analysis, and immunohistochemical labeling of endochondral markers, including sclerostin and MEPE. The endochondral phenotype of STR/Ort mice was analyzed by histologic examination, micro–computed tomography, and ex vivo organ culture. A novel protocol for quantifying bony bridges across the murine epiphysis (growth plate fusion) using synchrotron x-ray computed microtomography was developed and applied. Results: Meta-analysis of transcription profiles showed significant elevation in functions linked with endochondral ossification in STR/Ort mice (compared to CBA mice; P < 0.05). Consistent with this, immunolabeling revealed increased matrix metalloproteinase 13 (MMP-13) and type X collagen expression in STR/Ort mouse joints, and multiplex quantitative reverse transcriptase–PCR showed differential expression of known mineralization regulators, suggesting an inherent chondrocyte defect. Support for the notion of an endochondral defect included accelerated growth, increased zone of growth plate proliferative chondrocytes (P < 0.05), and widespread type X collagen/MMP-13 labeling beyond the expected hypertrophic zone distribution. OA development involved concomitant focal suppression of sclerostin/MEPE in STR/Ort mice. Our novel synchrotron radiation microtomography method showed increased numbers (P < 0.001) and mean areal growth plate bridge densities (P < 0.01) in young and aged STR/Ort mice compared to age-matched CBA mice. Conclusion: Taken together, our data support the notion of an inherent endochondral defect that is linked to growth dynamics and subject to regulation by the MEPE/sclerostin axis and may represent an underlying mechanism of pathologic ossification in OA.
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Nov 2015
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I13-2-Diamond Manchester Imaging
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Diamond Proposal Number(s):
[5003]
Abstract: Abnormal growth plate closure during endochondral ossification and subsequent deformity resulting from altered mechanical loading has key implications in the progression of joint deformities such as varus and valgus. Despite several studies investigating changes in bone growth in response to mechanical loading [1], there is a lack of 4D data (3D with time) quantifying the relationships between the closure of the growth plate and the local micro- mechanical environment that the cells in the epiphyseal growth plate may experience. We aimed to combine X-ray computed tomography and computational modelling to investigate whether there is a correlation between the 3D high resolution images of growth plate cartilage topology, the octahedral shear stress (believed to promote endochondral ossification [2]) and the spatial localisation of the bridges.
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Jun 2015
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I13-2-Diamond Manchester Imaging
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Diamond Proposal Number(s):
[5972, 8665]
Abstract: Increasing evidence implicates the re-initiation of embryonic processes, responsible for long bone development and growth, in osteoarthritic pathology. We aimed to establish whether an aberrant redeployment of the transient chondrocyte phenotype is observed in the STR/Ort mouse (spontaneous osteoarthritis), and whether this can be attributed to an inherent endochondral growth defect in these mice. Furthermore, we aimed to establish the role of the Wnt inhibitor sclerostin and its downstream target matrix extracellular phosphoglycoprotein (MEPE), a mineralisation inhibitor, in the maintenance of the healthy joint, and in the regulation of these endochondral processes in osteoarthritic joints.
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Apr 2014
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