Jukka S Jurvelin

University of Eastern Finland, Kuopio, Northern Savo, Finland

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Publications (427)1032.67 Total impact

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    ABSTRACT: Summary Due to the lack of diagnostics in primary health care, over 75 % of osteoporotic patients are not diagnosed. A new ultrasound method for primary health care is proposed. Results suggest applicability of ultrasound method for osteoporosis diagnostics at primary health care. Introduction We lack effective screening and diagnostics of osteoporosis at primary health care. In this study, a new ultrasound (US) method is proposed for osteoporosis diagnostics. Methods Atotal of 572 Caucasian women (age 20 to 91 years) were examined using pulse-echo US measurements in the tibia and radius. This method provides an estimate of bone mineral density (BMD), i.e. density index (DI). Areal BMD measurements at the femoral neck (BMDneck) and total hip (BMDtotal) were determined by using axial dual-energy Xray absorptiometry (DXA) for women older than 50 years of age (n=445, age=68.8±8.5 years). The osteoporosis thresholds for the DI were determined according to the International Society for Clinical Densitometry (ISCD). Finally, the FRAX questionnaire was completed by 425 participants. Results Osteoporosis was diagnosed in individuals with a Tscore −2.5 or less in the total hip or femoral neck (n=75). By using the ISCD approach for the DI, only 28.7 % of the subjects were found to require an additional DXA measurement. Our results suggest that combination of US measurement and FRAX in osteoporosis management pathways would decrease the number of DXA measurements to 16 % and the same treatment decisions would be reached at 85.4 % sensitivity and 78.5 % specificity levels. Conclusions The present results demonstrate a significant correlation between the ultrasound and DXA measurements at the proximal femur. The thresholds presented here with the application to current osteoporosis management pathways show promise for the technique to significantly decrease the amount of DXA referrals and increase diagnostic coverage; however, these results need to be confirmed in future studies.
    Osteoporosis International 11/2015; DOI:10.1007/s00198-015-3387-4 · 4.17 Impact Factor
  • Jarkko T Iivarinen · Rami K Korhonen · Jukka S Jurvelin ·
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    ABSTRACT: Exact physiological mechanisms behind the potential positive treatment effects of pathological tissue swelling (edema), such as increased interstitial fluid flow, are poorly understood. Finite-element model was created and the model response was matched with the deformation data from the negative pressure (suction) measurements in human (N = 11) forearm. Two experimental suction protocols were simulated to evaluate their impact on interstitial fluid flow in soft tissues. Simulated continuous suction was up to 27 times more efficient in fluid transportation compared to the cyclic suction. The continuous suction that transports the interstitial fluid effectively may help to decrease soft tissue edema.
    Computer Methods in Biomechanics and Biomedical Engineering 10/2015; DOI:10.1080/10255842.2015.1101073 · 1.77 Impact Factor

  • Arthroscopy Techniques 09/2015; DOI:10.1016/j.eats.2015.04.002
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    ABSTRACT: This study investigates the relationship between the optical response of human articular cartilage in the visible (VIS) and near infrared (NIR) spectral range and its matrix properties.Full-thickness osteochondral cores (dia. = 16 mm, n = 50) were extracted from human cadaver knees (N = 13) at four anatomical locations and divided into quadrants. Absorption spectra were acquired in the spectral range 400-1100 nm from one quadrant. Reference biomechanical, biochemical composition, histological, and cartilage thickness measurements were obtained from two other quadrants. A multivariate statistical technique based on partial least squares (PLS) regression was then employed to investigate the correlation between the absorption spectra and tissue properties.Our results demonstrate that cartilage optical response correlates with its function, composition and morphology, as indicated by the significant relationship between spectral predicted and measured biomechanical (79.0% ⩽ R(2) ⩽ 80.3%, p < 0.0001), biochemical (65.1% ⩽ R(2) ⩽ 81.0%, p < 0.0001), and histological scores ([Formula: see text] = 83.3%, p < 0.0001) properties. Significant correlation was also obtained with the non-calcified cartilage thickness ([Formula: see text] = 83.2%, p < 0.0001).We conclude that optical absorption of human cartilage in the VIS and NIR spectral range correlates with the overall tissue properties, thus providing knowledge that could facilitate development of systems for rapid assessment of tissue integrity.
    Physiological Measurement 08/2015; 36(9):1913-1928. DOI:10.1088/0967-3334/36/9/1913 · 1.81 Impact Factor
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    ABSTRACT: An attempt to define pre-osteoarthritis (OA) versus early OA and definitive osteoarthritis. A group of specialists in the field of cartilage science and treatment was formed to consider the nature of OA onset and its possible diagnosis. Late-stage OA, necessitating total joint replacement, is the end stage of a biological process, with many previous earlier stages. Early-stage OA has been defined and involves structural changes identified by arthroscopy or radiography. The group argued that before the "early-stage OA" there must exist a stage where cellular processes, due to the presence of risk factors, have kicked into action but have not yet resulted in structural changes. The group suggested that this stage could be called "pre-osteoarthritis" (pre-OA). The group suggests that defining points of initiation for OA in the knee could be defined, for example, by traumatic episodes or surgical meniscectomy. Such events may set in motion metabolic processes that could be diagnosed by modern MRI protocols or arthroscopy including probing techniques before structural changes of early OA have developed. Preventive measures should preferably be applied at this pre-OA stage in order to stop the projected OA "epidemic."
    Cartilage 07/2015; 6(3). DOI:10.1177/1947603515586048 · 0.69 Impact Factor
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    ABSTRACT: Areal bone mineral density (aBMD), as measured by dual-energy X-ray absorptiometry (DXA), predicts hip fracture risk only moderately. Simulation of bone mechanics based on DXA imaging of the proximal femur, may help to improve the prediction accuracy. Therefore, we collected three (1-3) image sets, including CT images and DXA images of 34 proximal cadaver femurs (set 1, including 30 males, 4 females), 35 clinical patient CT images of the hip (set 2, including 27 males, 8 females) and both CT and DXA images of clinical patients (set 3, including 12 female patients). All CT images were segmented manually and landmarks were placed on both femurs and pelvises. Two separate statistical appearance models (SAMs) were built using the CT images of the femurs and pelvises in sets 1 and 2, respectively. The 3D shape of the femur was reconstructed from the DXA image by matching the SAMs with the DXA images. The orientation and modes of variation of the SAMs were adjusted to minimize the sum of the absolute differences between the projection of the SAMs and a DXA image. The mesh quality and the location of the SAMs with respect to the manually placed control points on the DXA image were used as additional constraints. Then, finite element (FE) models were built from the reconstructed shapes. Mean point-to-surface distance between the reconstructed shape and CT image was 1.0 mm for cadaver femurs in set 1 (leave-one-out test) and 1.4 mm for clinical subjects in set 3. The reconstructed volumetric BMD showed a mean absolute difference of 140 and 185 mg/cm(3) for set 1 and set 3 respectively. The generation of the SAM and the limitation of using only one 2D image were found to be the most significant sources of errors in the shape reconstruction. The noise in the DXA images had only small effect on the accuracy of the shape reconstruction. DXA-based FE simulation was able to explain 85% of the CT-predicted strength of the femur in stance loading. The present method can be used to accurately reconstruct the 3D shape and internal density of the femur from 2D DXA images. This may help to derive new information from clinical DXA images by producing patient-specific FE models for mechanical simulation of femoral bone mechanics. Copyright © 2015 Elsevier B.V. All rights reserved.
    Medical image analysis 06/2015; 24(1). DOI:10.1016/j.media.2015.06.001 · 3.65 Impact Factor
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    ABSTRACT: The aim was to investigate the applicability of multivariate analysis of optical coherence tomography (OCT) information for determining structural integrity, composition and mechanical properties of articular cartilage. Equine osteochondral samples (N = 65) were imaged with OCT, and their total attenuation and backscattering coefficients (μt and μb) were measured. Subsequently, the Mankin score, optical density (OD), light absorbance in amide I region (Aamide), collagen orientation, permeability (k), fibril network modulus (Ef) and non-fibrillar matrix modulus (Em) of the samples were determined. Partial least squares (PLS) regression model was calculated to predict tissue properties from the OCT signals of the samples. Significant correlations between the measured and predicted mean collagen orientation (R(2) = 0.75, p < 0.0001), k (R(2) = 0.74, p < 0.0001), mean OD (R(2) = 0.73, p < 0.0001), Mankin scores (R(2) = 0.70, p < 0.0001), Em (R(2) = 0.50, p < 0.0001), Ef (R(2) = 0.42, p < 0.0001), and Aamide (R(2) = 0.43, p < 0.0001) were obtained. Significant correlation was also found between μb and Ef (ρ = 0.280, p = 0.03), but not between μt and any of the determined properties of articular cartilage (p > 0.05). Multivariate analysis of OCT signal provided good estimates for tissue structure, composition and mechanical properties. This technique may significantly enhance OCT evaluation of articular cartilage integrity, and could be applied, for example, in delineation of degenerated areas around cartilage injuries during arthroscopic repair surgery. Copyright © 2015. Published by Elsevier Ltd.
    Osteoarthritis and Cartilage 06/2015; DOI:10.1016/j.joca.2015.05.034 · 4.17 Impact Factor
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    ABSTRACT: Collagen, proteoglycans and chondrocytes can contribute to ultrasound scattering in articular cartilage. However, anisotropy of ultrasound scattering in cartilage is not fully characterized. We investigate this using a clinical intravascular ultrasound device with ultrasound frequencies of 9 and 40 MHz. Osteochondral samples were obtained from intact bovine patellas, and cartilage was imaged in two perpendicular directions: through articular and lateral surfaces. At both frequencies, ultrasound backscattering was higher (p < 0.05) when measured through the lateral surface of cartilage. In addition, the composition and structure of articular cartilage were investigated with multiple reference methods involving light microscopy, digital densitometry, polarized light microscopy and Fourier infrared imaging. Reference methods indicated that acoustic anisotropy of ultrasound scattering arises mainly from non-uniform distribution of chondrocytes and anisotropic orientation of collagen fibers. To conclude, ultrasound backscattering in articular cartilage was found to be anisotropic and dependent on the frequency in use. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.
    Ultrasound in medicine & biology 04/2015; 41(7). DOI:10.1016/j.ultrasmedbio.2015.03.021 · 2.21 Impact Factor
  • Mikael J. Turunen · Juha Toyras · Harri T Kokkonen · Jukka S. Jurvelin ·
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    ABSTRACT: Contrast agent enhanced cone beam computed tomography (CE-CBCT), a technique capable of high-resolution in vivo imaging with small radiation dose, has been applied successfully for clinical diagnostics of cartilage degeneration, i.e., osteoarthritis (OA). As an X-ray technique, CE-CBCT may also detect changes in mineral density of subchondral bone (volumetric bone mineral density, vBMD), known to be characteristic for OA. However, its feasibility for density measurements is not clear due to limited signal-to-noise ratio and contrast of CBCT images. In the present study, we created clinically applicable hydroxyapatite phantoms and determined vBMDs of cortical bone, trabecular bone, subchondral trabecular bone and subchondral plate of 10 cadaver (ex vivo) and 10 volunteer (in vivo) distal femora using a clinical CBCT scanner, and for reference, also using a conventional CT. Our results indicated strong linear correlations between the vBMD values measured with the CT and CBCT scanners (R2 > 0.90, p < 0.001), however, absolute vBMD values were dependent on the scanner in use. Further, the differences between the vBMDs of cortical bone, trabecular bone and subchondral bone were similar and independent of the scanner. The present results indicate that the vBMD values might not be directly comparable between different instruments. However, based on our present and previous results, we propose that, for OA diagnostics, clinical CBCT enables not only quantitative analysis of articular cartilage but also subchondral bone vBMD. Quantitative information on both cartilage and subchondral bone could be beneficial in OA diagnostics.
    04/2015; 34(10). DOI:10.1109/TMI.2015.2426684
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    ABSTRACT: Meniscal injuries can lead to mechanical overloading of articular cartilage and eventually to knee osteoarthritis. The objective was to evaluate the potential using of contrast enhanced computed tomography (CECT) to image contrast agent diffusion in human menisci with a clinical cone beam CT scanner. Isolated human menisci (n=26) were imaged using magnetic resonance imaging (MRI) and CECT in situ. Diffusion of anionic contrast agent into the meniscus was imaged for up to 30 hours. The results of CECT were compared with water, collagen and proteoglycan (PG) contents, biomechanical properties, age and histological and MR images of the samples. Diffusion of contrast agent required over 25 hours to reach equilibrium. The contrast agent partition (the contrast agent concentration in the tissue divided by that in the bath) at the 40 minute time point correlated significantly with that at the 30 hour time point in both lateral (r=0.706, p=0.007) and medial (r=0.669, p=0.012) menisci. Furthermore, contrast agent partition in meniscus after 30 hours of diffusion agreed qualitatively with the distribution of PGs. The cross-sectional distribution of contrast agent was consistent with that reported in a previous μCT study on bovine meniscus. The time required to reach diffusion equilibrium was found impractical for clinical applications. However, based on the present results, shorter delay between injection and imaging (e.g. 40 minutes) could be feasible in clinical diagnostics of meniscal pathologies. Copyright © 2015. Published by Elsevier Ltd.
    Osteoarthritis and Cartilage 04/2015; 23(8). DOI:10.1016/j.joca.2015.03.037 · 4.17 Impact Factor
  • Puhakka PH · te Moller NCR · Afara IO · Brommer H · Tiitu V · Viren T · Jurvelin JS · Töyräs J. ·

    Annual Meeting of the Orthopaedic Research Society, Las Vegas, Nevada, United States; 03/2015
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    Isaac Afara · Honkanen JTJ · Danso EK · Korhonen RK · Jurvelin JS · Töyräs J ·

    Annual Meeting of the Orthopaedic Research Soceity, Las Vegas, Nevada, United States.; 03/2015

  • Orthopaedic Research Society 2015 Annual Meeting, Las Vegas, Nevada; 03/2015
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    ABSTRACT: In this study, we explore topographical changes in proteoglycan distribution from femoral condylar cartilage in early osteoarthritis, acquired from both the lateral and medial condyles of anterior cruciate ligament transected (ACLT) and contralateral (CNTRL) rabbit knee joints, at 4 weeks post operation. Four sites across the cartilage surface in a parasagittal plane were defined across tissue sections taken from femoral condyles and proteoglycan (PG) content was quantified using digital densitometry. The greatest depth-wise change in PG content due to an ACLT (compared to the CNTRL group) was observed anteriorly (site C) from the most weight-bearing location within the lateral compartment. In the medial compartment, the greatest change was observed in the most weight-bearing location (site B). The depth-wise changes in PG content were observed up to 48% and 28% depth from the tissue surface at these aforementioned sites, respectively (p < 0.05). The smallest depth-wise change in PG content was observed posteriorly (site A) from the most weight-bearing location within both femoral condyles (up to 20% and up to 5% depth from the tissue surface at lateral and medial compartments, respectively). This study gives further insight into how early cartilage deterioration progresses across the parasagittal plane of the femoral condyle. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
    Journal of Orthopaedic Research 03/2015; 33(9). DOI:10.1002/jor.22906 · 2.99 Impact Factor
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    ABSTRACT: Meniscus adapts to joint loads by depth- and site-specific variations in its composition and structure. However, site-specific mechanical characteristics of intact meniscus under compression are poorly known. In particular, mechanical nonlinearities caused by different meniscal constituents (collagen and fluid) are not known. In the current study, in situ indentation testing was conducted to determine site-specific elastic, viscoelastic and poroelastic properties of intact human menisci. Lateral and medial menisci (n=26) were harvested from the left knee joint of 13 human cadavers. Indentation tests, using stress-relaxation and dynamic (sinusoidal) loading protocols, were conducted for menisci at different sites (anterior, middle, posterior, n=78). Sample- and site-specific axisymmetric finite element models with fibril-reinforced poroelastic properties were fitted to the corresponding stress-relaxation curves to determine the mechanical parameters. Elastic moduli, especially the instantaneous and dynamic moduli, showed site-specific variation only in the medial meniscus (p<0.05 between the sites). The instantaneous and dynamic elastic moduli of the anterior horn were significantly (p<0.05) greater in the medial than lateral meniscus. The phase angle showed no statistically significant variation between the sites (p>0.05). The values for the strain-dependent fibril network modulus (nonlinear behaviour of collagen) were significantly different (p<0.05) between all sites in the medial menisci. Additionally, there was a significant difference (p<0.01) in the strain-dependent fibril network modulus between the lateral and medial anterior horns. The initial permeability was significantly different (p<0.05) in the medial meniscus only between the middle and posterior sites. For the strain-dependent permeability coefficient, only anterior and middle sites showed a significant difference (p<0.05) in the medial meniscus. This parameter demonstrated a significant difference (p<0.05) between lateral and medial menisci at the anterior horns. Our results reveal that under in situ indentation loading, medial meniscus shows more site-dependent variation in the mechanical properties as compared to lateral meniscus. In particular, anterior horn of medial meniscus was the stiffest and showed the most nonlinear mechanical behaviour. The nonlinearity was related to both collagen fibrils and fluid. Copyright © 2015 Elsevier Ltd. All rights reserved.
    Journal of Biomechanics 02/2015; 48(8). DOI:10.1016/j.jbiomech.2015.01.048 · 2.75 Impact Factor
  • Xiaoyu Tong · Inari S Burton · Hanna Isaksson · Jukka S Jurvelin · Heikki Kröger ·
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    ABSTRACT: Low bone volume and changes in bone quality or microarchitecture may predispose individuals to fragility fractures. As the dominant component of the human skeleton, cortical bone plays a key role in protecting bones from fracture. However, histological investigations of the underlying structural changes, which might predispose to fracture, have been largely limited to the cancellous bone. The aim of this study was to investigate the age-association and regional differences of histomorphometric properties in the femoral neck cortical bone. Undecalcified histological sections of the femoral neck (n = 20, aged 18-82 years, males) were cut (15 μm) and stained using modified Masson-Goldner stain. Complete femoral neck images were scanned, and cortical bone boundaries were defined using our previously established method. Cortical bone histomorphometry was performed with low (×50) and high magnification (×100). Most parameters related to cortical width (Mean Ct.Wi, Inferior Ct.Wi, Superior Ct.Wi) were negatively associated with age both before and after adjustment for height. The inferior cortex was the thickest (P < 0.001) and the superior cortex was the thinnest (P < 0.008) of all cortical regions. Both osteonal size and pores area were negatively associated with age. Osteonal area and number were higher in the antero-inferior area (P < 0.002) and infero-posterior area (P = 0.002) compared to the postero-superior area. The Haversian canal area was higher in the infero-posterior area compared to the postero-superior area (P = 0.002). Moreover, porosity was higher in the antero-superior area (P < 0.002), supero-anterior area (P < 0.002) and supero-posterior area (P < 0.002) compared to the infero-anterior area. Eroded endocortical perimeter (E.Pm/Ec.Pm) correlated positively with superior cortical width. This study describes the changes in cortical bone during ageing in healthy males. Further studies are needed to investigate whether these changes explain the increased susceptibility to femoral neck fractures.
    Calcified Tissue International 02/2015; 96(4). DOI:10.1007/s00223-015-9957-9 · 3.27 Impact Factor
  • Mikael J Turunen · Juha Töyräs · Harri Kokkonen · Jukka S Jurvelin ·

    Annual meeting of the Orthopaedic Research Society, Las Vegas, NV; 01/2015

  • Annual meeting of the Orthopaedic Research Society, Las Vegas, NV; 01/2015
  • X Ojanen · H Isaksson · J Töyräs · M J Turunen · M K H Malo · A Halvari · J S Jurvelin ·
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    ABSTRACT: Trabecular bone is a metabolically active tissue with a high surface to volume ratio. It exhibits viscoelastic properties that may change during aging. Changes in bone properties due to altered metabolism are sensitively revealed in trabecular bone. However, the relationships between material composition and viscoelastic properties of bone, and their changes during aging have not yet been elucidated. In this study, trabecular bone samples from the femoral neck of male cadavers (n=21) aged 17-82 years were collected and the tissue level composition and its associations with the tissue viscoelastic properties were evaluated by using Raman microspectroscopy and nanoindentation, respectively. For composition, collagen content, mineralization, carbonate substitution and mineral crystallinity were evaluated. The calculated mechanical properties included reduced modulus (Er), hardness (H) and the creep parameters (E1, E2, η1and η2), as obtained by fitting the experimental data to the Burgers model. The results indicated that the creep parameters, E1, E2, η1and η2, were linearly correlated with mineral crystallinity (r=0.769-0.924, p<0.001). Creep time constant (η2/E2) tended to increase with crystallinity (r=0.422, p=0.057). With age, the mineralization decreased (r=-0.587, p=0.005) while the carbonate substitution increased (r=0.728, p<0.001). Age showed no significant associations with nanoindentation parameters. The present findings suggest that, at the tissue-level, the viscoelastic properties of trabecular bone are related to the changes in characteristics of bone mineral. This association may be independent of human age. Copyright © 2014 Elsevier Ltd. All rights reserved.
    Journal of Biomechanics 12/2014; 48(2). DOI:10.1016/j.jbiomech.2014.11.034 · 2.75 Impact Factor
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    ABSTRACT: To quantify early osteoarthritic-like changes in the structure and volume of subchondral bone plate and trabecular bone and properties of articular cartilage in a rabbit model of osteoarthritis induced by anterior cruciate ligament transection (ACLT). Left knee joints from eight skeletally mature New Zealand white rabbits underwent ACLT surgery, while the contralateral (CTRL) right knee joints were left unoperated. Femoral condyles were harvested 4 weeks after ACLT. Micro-computed tomography imaging was applied to evaluate the structural properties of subchondral bone plate and trabecular bone. Additionally, biomechanical properties, structure and composition of articular cartilage were assessed. As a result of ACLT, significant thinning of the subchondral bone plate (P < 0.05) was accompanied by significantly reduced trabecular bone volume fraction and trabecular thickness in the medial femoral condyle compartment (P < 0.05), while no changes were observed in the lateral compartment. In both lateral and medial femoral condyles, the equilibrium modulus and superficial zone proteoglycan content were significantly lower in ACLT than CTRL joint cartilage (P < 0.05). Significant alterations in the collagen orientation angle extended substantially deeper into cartilage from the ACLT joints in the lateral femoral condyle relative to the medial condyle compartment (P < 0.05). In this model of early osteoarthritis, significant changes in volume and microstructure of subchondral bone plate and trabecular bone were detected only in the femoral medial condyle, while alterations in articular cartilage properties were more severe in the lateral compartment. The former finding may be associated with reduced joint loading in the medial compartment due to ACLT, while the latter finding reflects early osteoarthritic changes in the lateral compartment. Copyright © 2014. Published by Elsevier Ltd.
    Osteoarthritis and Cartilage 12/2014; 23(3). DOI:10.1016/j.joca.2014.11.023 · 4.17 Impact Factor

Publication Stats

11k Citations
1,032.67 Total Impact Points


  • 2009-2015
    • University of Eastern Finland
      • • Department of Applied Physics
      • • Department of Physics and Mathematics
      Kuopio, Northern Savo, Finland
  • 1992-2012
    • Kuopio University Hospital
      • • Department of Clinical Neurophysiology
      • • Department of Clinical Physiology and Nuclear Medicine
      Kuopio, Eastern Finland Province, Finland
  • 1984-2011
    • University of Kuopio
      • • Department of Physics
      • • Department of Applied Physics
      • • Department of Anatomy
      • • Department of Clinical Physiology
      Kuopio, Eastern Finland Province, Finland
  • 2005
    • Lappeenranta University of Technology
      Villmanstrand, Southern Finland Province, Finland
    • Helsinki University Central Hospital
      • Department of Orthopaedics and Traumatology
      Helsinki, Province of Southern Finland, Finland
  • 1997
    • Universität Bern
      Berna, Bern, Switzerland
  • 1995
    • Oulu University Hospital
      Uleoborg, Northern Ostrobothnia, Finland
  • 1993
    • University of Turku
      • Department of Medical Biochemistry and Genetics
      Turku, Southwest Finland, Finland