Jaakko Niinimäki

University of Oulu, Oulu, Oulu, Finland

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Publications (37)77.67 Total impact

  • Article: Influence of physical activity on vertebral strength during late adolescence.
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    ABSTRACT: BACKGROUND CONTEXT: Reduced vertebral strength is a clear risk factor for vertebral fractures. Men and women with vertebral fractures often have reduced vertebral size and bone mineral density (BMD). Vertebral strength is controlled by both genetic and developmental factors. Malnutrition and low levels of physical activity are commonly considered to result in reduced bone size during growth. Several studies have also demonstrated the general relationship between BMD and physical activity in the appendicular skeleton. PURPOSE: In this study, we wanted to clarify the role of physical activity on vertebral bodies. Vertebral dimensions appear to generally be less pliant than long bones when lifetime changes occur. We wanted to explore the association between physical activity during late adolescence and vertebral strength parameters such as cross-sectional size and BMD. STUDY DESIGN: The association between physical activity and vertebral strength was explored by measuring vertebral strength parameters and defining the level of physical activity during adolescence. PATIENT SAMPLE: The study population consisted of 6,928 males and females who, at 15 to 16 and 19 years of age, responded to a mailed questionnaire inquiring about their physical activity. A total of 558 individuals at the mean age of 21 years underwent magnetic resonance imaging (MRI) scans. METHODS: We measured the dimensions of the fourth lumbar vertebra from the MRI scans of the Northern Finland Birth Cohort 1986 and performed T2* relaxation time mapping, reflective of BMD. Vertebral strength was based on these two parameters. We analyzed the association of physical activity on vertebral strength using the analysis of variance. RESULTS AND CONCLUSIONS: We observed no association between the level of physical activity during late adolescence and vertebral strength at 21 years.
    The spine journal: official journal of the North American Spine Society 01/2013; · 2.90 Impact Factor
  • Article: Association of abdominal obesity with lumbar disc degeneration - a magnetic resonance imaging study.
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    ABSTRACT: To evaluate whether midsagittal (abdominal) obesity in magnetic resonance imaging (MRI), waist circumference (WC) and body fat percentage are associated with lumbar disc degeneration in early adulthood. We obtained the lumbar MRI (1.5-T scanner) of 325 females and 233 males at a mean age of 21 years. Lumbar disc degeneration was evaluated using Pfirrmann classification. We analysed the associations of MRI measures of obesity (abdominal diameter (AD), sagittal diameter (SAD), ventral subcutaneous thickness (VST), and dorsal subcutaneous thickness (DST)), WC and body fat percentage with disc degeneration sum scores using ordinal logistic regression. A total of 155 (48%) females and 147 (63%) males had disc degeneration. AD and SAD were associated with a disc degeneration sum score of ≥3 compared to disc degeneration sum score of 0-2 (OR 1.67; 95% confidence interval (CI) 1.20-2.33 and OR 1.40; 95% CI 1.12-1.75, respectively) among males, but we found no association among females. WC was also associated with disc degeneration among males (OR 1.03 per one cm; 95% CI 1.00-1.05), but not among females. Measures of abdominal obesity in MRI and waist circumference were associated with disc degeneration among 21-year-old males.
    PLoS ONE 01/2013; 8(2):e56244. · 4.09 Impact Factor
  • Article: Body mass index is associated with lumbar disc degeneration in young Finnish males: subsample of Northern Finland birth cohort study 1986.
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    ABSTRACT: The role of environmental factors in lumbar intervertebral disc degeneration (DD) in young adults is largely unknown. Therefore, we investigated whether body mass index (BMI), smoking, and physical activity are associated with lumbar DD among young adults. The Oulu Back Study (OBS) is a subpopulation of the 1986 Northern Finland Birth Cohort (NFBC 1986) and it originally included 2,969 children. The OBS subjects received a postal questionnaire, and those who responded (N = 1,987) were invited to the physical examination. The participants (N = 874) were invited to lumbar MRI study. A total of 558 young adults (325 females and 233 males) underwent MRI that used a 1.5-T scanner at the mean age of 21. Each lumbar intervertebral disc was graded as normal (0), mildly (1), moderately (2), or severely (3) degenerated. We calculated a sum score of the lumbar DD, and analyzed the associations between environmental risk factors (smoking, physical activity and weight-related factors assessed at 16 and 19 years) and DD using ordinal logistic regression, the results being expressed as cumulative odds ratios (COR). All analyses were stratified by gender. Of the 558 subjects, 256 (46%) had no DD, 117 (21%) had sum score of one, 93 (17%) sum score of two, and 92 (17%) sum score of three or higher. In the multivariate ordinal logistic regression model, BMI at 16 years (highest vs. lowest quartile) was associated with DD sum score among males (COR 2.35; 95% CI 1.19-4.65) but not among females (COR 1.29; 95% CI 0.72-2.32). Smoking of at least four pack-years was associated with DD among males, but not among females (COR 2.41; 95% CI 0.99-5.86 and 1.59; 95% 0.67-3.76, respectively). Self-reported physical activity was not associated with DD. High BMI at 16 years was associated with lumbar DD at 21 years among young males but not among females. High pack-years of smoking showed a comparable association in males, while physical activity had no association with DD in either gender. These results suggest that environmental factors are associated with DD among young males.
    BMC Musculoskeletal Disorders 01/2013; 14:87. · 1.58 Impact Factor
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    Dataset: Influence of physical activity on vertebral size
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    Article: Association of modic changes, Schmorl's nodes, spondylolytic defects, high-intensity zone lesions, disc herniations, and radial tears with low back symptom severity among young Finnish adults.
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    ABSTRACT: A cross-sectional magnetic resonance imaging (MRI) study. We investigated the association among Modic changes, Schmorl's nodes, spondylolytic defects, high-intensity zone lesions, radial tears, herniations, and low back symptom severity. Disc degeneration is associated with low back pain in early adulthood, but the associations between other MRI findings and low back pain are not well known. Questionnaire data and MRI scans (1.5-T) were available for 554 subjects derived from a birth cohort at 21 years of age. Data on low back pain and back-related functional limitations at 18, 19, and 21 years of age were used for clustering of subjects, using latent class analysis. We used logistic regression with adjustment for the degree of disc degeneration to evaluate the associations between specific imaging findings and low back symptom severity. The prevalence of herniations was 20%, Schmorl's nodes 17%, radial tears 9.9%, high-intensity zone lesions 3.2%, spondylolytic defects 5.8%, and Modic changes 0.7%. Latent class analysis produced 5 clusters: "Always Painful" (n = 65) meant painful at all time points and "Recent Onset Pain" (n = 56) meant increasing symptom severity, whereas subjects in the "Moderately Painful" (n = 73), "Minor Pain" (n = 193), and "No Pain" (n = 167) clusters had fewer symptoms. Compared with the "No Pain" cluster, Schmorl's nodes were more likely to occur in the "Always Painful" cluster (P = 0.017) and herniations in the 3 most painful clusters (P < 0.001). Herniations were associated with low back symptom severity (odds ratio, 2.5; 95% confidence interval, 1.4-4.4). Schmorl's nodes and radial tears were associated with symptoms in crude analyses only, whereas high-intensity zone lesions and spondylolytic defects occurred in similar frequencies in all clusters. Herniations were most likely in the subjects with recent onset or persistent (3-yr period) low back symptoms, although they were also detected in subjects with no symptoms. The clinical relevance of herniations on MRI remains to be evaluated in the context of symptoms.
    Spine 12/2011; 37(14):1231-9. · 2.08 Impact Factor
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    Article: Genetic susceptibility of intervertebral disc degeneration among young Finnish adults.
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    ABSTRACT: Disc degeneration (DD) is a common condition that progresses with aging. Although the events leading to DD are not well understood, a significant genetic influence has been found. This study was undertaken to assess the association between relevant candidate gene polymorphisms and moderate DD in a well-defined and characterized cohort of young adults. Focusing on young age can be valuable in determining genetic predisposition to DD. We investigated the associations of existing candidate genes for DD among 538 young adults with a mean age of 19 belonging to the 1986 Northern Finland Birth Cohort. Nineteen single nucleotide polymorphisms (SNP) in 16 genes were genotyped. We evaluated lumbar DD using the modified Pfirrmann classification and a 1.5-T magnetic resonance scanner for imaging. Of the 538 individuals studied, 46% had no degeneration, while 54% had DD and 51% of these had moderate DD. The risk of DD was significantly higher in subjects with an allele G of IL6 SNPs rs1800795 (OR 1.45, 95% CI 1.07-1.96) and rs1800797 (OR 1.37, 95% CI 1.02-1.85) in the additive inheritance model. The role of IL6 was further supported by the haplotype analysis, which resulted in an association between the GGG haplotype (SNPs rs1800797, rs1800796 and rs1800795) and DD with an OR of 1.51 (95% CI 1.11-2.04). In addition, we observed an association between DD and two other polymorphisms, SKT rs16924573 (OR 0.27 95% CI 0.07-0.96) and CILP rs2073711 in women (OR 2.04, 95% CI 1.07-3.89). Our results indicate that IL6, SKT and CILP are involved in the etiology of DD among young adults.
    BMC Medical Genetics 11/2011; 12:153. · 2.33 Impact Factor
  • Article: A characteristic time sequence of epileptic activity in EEG during dynamic penicillin-induced focal epilepsy--a preliminary study.
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    ABSTRACT: Penicillin-induced focal epilepsy is a well-known model in experimental epilepsy. However, the dynamic evolution of waveforms, DC-level changes, spectral content and coherence are rarely reported. Stimulated by earlier fMRI findings, we also seek for the early signs preceding spiking activity from frequency domain of EEG signal. In this study, EEG data is taken from previous EEG/fMRI series (six pigs, 20-24kg) of an experimental focal epilepsy model, which includes dynamic induction of epileptic activity with penicillin (6000IU) injection into the somatosensory cortex during deep isoflurane anaesthesia. No ictal discharges were recorded with this dose. Spike waveforms, DC-level, time-frequency content and coherence of EEG were analysed. Development of penicillin induced focal epileptic activity was not preceded with specific spectral changes. The beginning of interictal spiking was related to power increase in the frequencies below 6Hz or 20Hz, and continued to a widespread spectral increase. DC-level and coherence changes were clear in one animal. Morphological evolution of epileptic activity was a collection of the low-amplitude monophasic, bipolar, triple or double spike-wave forms, with an increase in amplitude, up to large monophasic spiking. In conclusion, in the time sequence of induced epileptic activity, immediate shifts in DC-level EEG are plausible, followed by the spike activity-related widespread increase in spectral content. Morphological evolution does not appear to follow a clear continuum; rather, intermingled and variable spike or multispike waveforms generally lead to stabilised activity of high-amplitude monophasic spikes.
    Seizure 04/2011; 20(7):513-9. · 1.80 Impact Factor
  • Article: Assessment of association between low back pain and paraspinal muscle atrophy using opposed-phase magnetic resonance imaging: a population-based study among young adults.
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    ABSTRACT: A cross-sectional imaging study of young adults. To evaluate whether severity of low back symptoms predicts atrophy in the paraspinal muscles of young adults. Although an increased fat content of the lumbar muscles has been observed among adults with chronic LBP, there is limited knowledge of this association in younger populations. The population-based study sample consisted of 554 subjects (321 females and 233 males) from the 1986 Northern Finland Birth Cohort. Latent Class Analysis (LCA) was used to cluster the subjects according to the low back symptoms and functional limitations at 18, 19, and 21 years. The mean age of the subjects at the time of the MRI (magnetic resonance imaging) was 21 years (range, 20-23). Muscle atrophy was evaluated by assessing the fat content of the paraspinal muscles using Opposed-Phase MRI. The cross-sectional areas (CSAs) of the erector spinae and multifidus muscles were also measured. LCA analysis produced five clusters differing in symptoms, ranging from a cluster (n = 65) in which subjects had high likelihood of symptoms and functional limitations at all time points, to a cluster (n = 165) with no pain ever. The fat content of the multifidus muscles was significantly higher among women than men (14.0% vs. 5.3%, P < 0.001), but it was not significantly associated with symptom severity. The CSA of both erector spinae and multifidus muscles were significantly larger among men than women (P < 0.001 in all of the muscles), but were not associated with pain severity. Low back symptoms and functional limitations over a 3-year period were not associated with increased fat content or a reduction in the cross-sectional area of lumbar paraspinal muscles among young adults.
    Spine 02/2011; 36(23):1961-8. · 2.08 Impact Factor
  • Article: Does lumbar disc degeneration on magnetic resonance imaging associate with low back symptom severity in young Finnish adults?
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    ABSTRACT: A cross-sectional magnetic resonance imaging study with questionnaires on low back pain (LBP) and functional limitations. To investigate the association between lumbar intervertebral disc degeneration (DD) and low back symptom severity among young Finnish adults. Both LBP and lumbar DD are common already in adolescence, but very little is known of their association in young adults. Young adults belonging to a birth cohort (n=874) were invited to lumbar magnetic resonance imaging using a 1.5-T scanner. Data on LBP and functional limitations at the ages of 18, 19, and 21 years were used to cluster the subjects with respect to low back symptoms using latent class analysis. The prevalence and 95% confidence intervals of DD at 21 years and the sum score of DD at all lumbar levels were compared between the clusters. The contribution of DD and other imaging findings (herniations, anular tears, Modic changes, spondylolytic defects) to symptom severity was analyzed with logistic regression analysis. Latent class analysis produced five clusters from the 554 subjects, ranging from a cluster where subjects (n=65) had been painful at all time points to an asymptomatic cluster (n=168). DD was more prevalent in the three most symptomatic clusters compared to the two least symptomatic ones. Similar findings were obtained for the DD sum scores. Lumbar DD was related to symptom severity independently of other degenerative findings. Moreover, moderately degenerated discs were more likely than mildly degenerated discs to be associated with the most severe low back symptoms. Intervertebral DD was associated with low back symptom severity among young adults, suggesting that the symptoms may have a discogenic origin at this age. However, DD was also found in one-third of asymptomatic subjects.
    Spine 02/2011; 36(25):2180-9. · 2.08 Impact Factor
  • Article: Influence of physical activity on vertebral size.
    Osteoporosis International 01/2011; 22(1):371-2. · 4.58 Impact Factor
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    Chapter: RUNGIUKSEN MUUMION OSTEOANTROPOLOGINEN TUTKIMUS
    01/2011: pages 265-274; , ISBN: 978-952-92-9577-7
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    Article: The standing fixed flexion view detects narrowing of the joint space better than the standing extended view in patients with moderate osteoarthritis of the knee.
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    ABSTRACT: It is unclear whether osteoarthritis (OA) of the knee is seen better in standing flexion position radiographs than in the standing extended view. We assessed the value of standing flexion views. We retrospectively evaluated 1,090 radiographs of 545 consecutive knees with non-traumatic knee pain, comparing standing fixed flexion view (FFV) and standing extended view (SEV). OA was classified according to the Kellgren-Lawrence (KL) radiographic grading scale and joint space widths were measured. Medial joint space width was lower on average in the FFV, with the greatest difference in KL II knees. Medial full-thickness loss of cartilage was also seen more often in the FFVs of knees with moderate OA (KL II-III) than in the SEVs (6% vs. 19%). Using FFV, there is no need to measure the exact knee flexion angle to use fluoroscopy. In earlier studies, the FFV has been found to be reproducible and easy to use in clinical practice. We recommend using flexion views when deciding the appropriate type of intervention in patients with OA. Full-thickness loss of cartilage in particular is better seen in the flexion view, which may be helpful if planning unicompartmental knee arthroplasty.
    Acta Orthopaedica 06/2010; 81(3):344-6. · 2.17 Impact Factor
  • Article: [Displays at health centers insufficient for radiological diagnostics].
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    ABSTRACT: The quality of workstation displays and viewing conditions affect the diagnostic information visible from digital radiographs. The image viewing practice at health centers in Northern Finland were surveyed with a questionnaire filled by 91 physicians. The quality of 23 monitors at ten health centers was measured. Display performance and viewing conditions were poor. Sixty percent of radiographic exams remained without a statement from a radiologist. Only few physicians assessed the quality of displays. Health centers should invest into displays of diagnostic quality, consider the viewing conditions and perform systematic quality assurance of medical displays.
    Duodecim; lääketieteellinen aikakauskirja 01/2010; 126(6):650-8.
  • Article: Prevalence of degenerative imaging findings in lumbar magnetic resonance imaging among young adults.
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    ABSTRACT: A cross-sectional imaging study of young adults. To investigate the prevalence of disc degeneration (DD) and displacement, anular tears, and Modic changes in lumbar magnetic resonance imaging (MRI) among young adults. Although low back pain in young adulthood is common, the prevalence of spinal MRI findings at this age remains virtually unknown. The study population was a subcohort of the Northern Finland Birth Cohort 1986. Subjects living within 100 km of Oulu (n = 874) were invited to participate in lumbar MRI at 20 to 22 years of age (mean: 21.2 years). Degree of DD, type of Modic changes, and presence of disc bulges, herniations, high intensity zone (HIZ) lesions, and radial tears at all lumbar levels were assessed. Three hundred twenty-five women and 233 men (n = 558) attended the MR imaging. DD was significantly more frequent in men (54% vs. 42%, P = 0.005), as was multiple DD (21% vs. 14%, P = 0.036). The prevalences of disc bulges and radial tears were 25% and 9.1%, respectively, without gender differences. HIZ lesions were more common among women than men (8.6% vs. 4.3%, P = 0.046), whereas herniations were significantly more common among men (5.6% vs. 2.5%, P = 0.047). Only 2 disc extrusions were observed, one in each gender. All degenerative disc findings were more common at the L5-S1 level except HIZ lesions, which were most likely at L4-L5. The prevalence of the Modic changes was 1.4%, without gender difference, type I being more common than type II. Typically, Modic changes were located adjacent to a DD Grade 4 disc and at the 2 lowest levels. Almost half of young Finnish adult aged 21 years had at least one degenerated disc, and a quarter had a bulging disc. Modic changes and disc herniations were, however, relatively rare.
    Spine 07/2009; 34(16):1716-21. · 2.08 Impact Factor
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    Article: Temporal trends in vertebral size and shape from medieval to modern-day.
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    ABSTRACT: Human lumbar vertebrae support the weight of the upper body. Loads lifted and carried by the upper extremities cause significant loading stress to the vertebral bodies. It is well established that trauma-induced vertebral fractures are common especially among elderly people. The aim of this study was to investigate the morphological factors that could have affected the prevalence of trauma-related vertebral fractures from medieval times to the present day. To determine if morphological differences existed in the size and shape of the vertebral body between medieval times and the present day, the vertebral body size and shape was measured from the 4th lumbar vertebra using magnetic resonance imaging (MRI) and standard osteometric calipers. The modern samples consisted of modern Finns and the medieval samples were from archaeological collections in Sweden and Britain. The results show that the shape and size of the 4th lumbar vertebra has changed significantly from medieval times in a way that markedly affects the biomechanical characteristics of the lumbar vertebral column. These changes may have influenced the incidence of trauma- induced spinal fractures in modern populations.
    PLoS ONE 02/2009; 4(3):e4836. · 4.09 Impact Factor
  • Article: Association between visual degeneration of intervertebral discs and the apparent diffusion coefficient.
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    ABSTRACT: The value of apparent diffusion coefficient (ADC) measurements in intervertebral disc has been studied because ADC provides an estimate of free diffusion of unbound water and could be used as a quantitative tool to estimate degenerative changes. However, the challenging nature of diffusion imaging of spine and limited numbers of subjects in earlier studies has produced contradictory findings. We aimed to determine the relation between ADC and visual degenerative changes in lumbar intervertebral discs in a sufficiently large homogeneous study group. Lumbar spines of 228 volunteer middle-aged men were MR imaged at 1.5 T including anatomic and diffusion-weighted imaging. ADC values, T2 signal intensity and height, and width of the three lowest lumbar intervertebral discs were measured and disc degeneration visually graded. The calculated average ADC of 530 measured discs was 2.01 x 10(-3) mm(2)/s+/-0.29 (+/-S.D.). The reduction in ADC between visually normal and moderately degenerated discs was 4%. Severely degenerated discs showed 5% larger ADC values than normal discs, presumably due to free water in cracks and fissures of those discs. T2 signal intensity of the disc was significantly correlated with the ADC values, whereas other measured parameters did not show correlation. There was no evident difference in ADC between the studied anatomic lumbar levels. Because there is considerable overlap between ADC values of normal and degenerated discs, we conclude that ADC measurements of intervertebral discs, at least with current technology, have limited clinical value.
    Magnetic Resonance Imaging 01/2009; 27(5):641-7. · 1.99 Impact Factor
  • Article: Vertebral endplate signal changes (Modic change): a systematic literature review of prevalence and association with non-specific low back pain.
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    ABSTRACT: The prevalence of "vertebral endplate signal changes" (VESC) and its association with low back pain (LBP) varies greatly between studies. This wide range in reported prevalence rates and associations with LBP could be explained by differences in the definitions of VESC, LBP, or study sample. The objectives of this systematic critical review were to investigate the current literature in relation to the prevalence of VESC (including Modic changes) and the association with non-specific low back pain (LBP). The MEDLINE, EMBASE, and SveMED databases were searched for the period 1984 to November 2007. Included were the articles that reported the prevalence of VESC in non-LBP, general, working, and clinical populations. Included were also articles that investigated the association between VESC and LBP. Articles on specific LBP conditions were excluded. A checklist including items related to the research questions and overall quality of the articles was used for data collection and quality assessment. The reported prevalence rates were studied in relation to mean age, gender, study sample, year of publication, country of study, and quality score. To estimate the association between VESC and LBP, 2 x 2 tables were created to calculate the exact odds ratio (OR) with 95% confidence intervals. Eighty-two study samples from 77 original articles were identified and included in the analysis. The median of the reported prevalence rates for any type of VESC was 43% in patients with non-specific LBP and/or sciatica and 6% in non-clinical populations. The prevalence was positively associated with age and was negatively associated with the overall quality of the studies. A positive association between VESC and non-specific LBP was found in seven of ten studies from the general, working, and clinical populations with ORs from 2.0 to 19.9. This systematic review shows that VESC is a common MRI-finding in patients with non-specific LBP and is associated with pain. However, it should be noted that VESC may be present in individuals without LBP.
    European Spine Journal 10/2008; 17(11):1407-22. · 1.97 Impact Factor
  • Article: Modic changes in vertebral endplates: a comparison of MR imaging and multislice CT.
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    ABSTRACT: This paper aims to evaluate the presence of endplate sclerosis in different types of Modic changes and to assess the capability of MRI in detecting endplate sclerosis within these changes. The lumbar spines (L3-S1) of 70 patients were retrospectively reviewed to determine Modic changes and disc degeneration from MRI and endplate sclerosis from CT. T1- and T2-weighted signal intensity and Hounsfield unit (HU) measurements of type I and II Modic changes were recorded and the association of both Modic types I and II with endplate sclerosis was analyzed with a Mann-Whitney test. Altogether 82 Modic changes in 36 subjects were recorded: 13% were type I, 12% mixed type I/II, 65% type II, 9% mixed type II/III, and 1% type III. Thirty-eight percent of the endplates with Modic changes had sclerosis in CT. Of specific Modic types, mixed I/II and II/III associated significantly with endplate sclerosis. Endplate sclerosis was not detected in MRI in a quantitative analysis. Endplate sclerosis exists in all types of Modic changes, especially in mixed Modic types, and not only in type III changes, as previously assumed. Endplate sclerosis was not detected in MRI, which may depend on the amount of mineralization of the bone marrow.
    Skeletal Radiology 10/2008; 38(2):141-7. · 1.54 Impact Factor
  • Article: Association of lumbar artery narrowing, degenerative changes in disc and endplate and apparent diffusion in disc on postcontrast enhancement of lumbar intervertebral disc.
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    ABSTRACT: A decreased supply of nutrition to the intervertebral disc can lead to disc degeneration. Nutrient supply can be simulated in vivo by measuring gadolinium enhancement of the disc. We aimed to study the changes associated with disc degeneration that may have effect on the nutrition of the disc, i.e. lumbar artery narrowing, Modic changes, endplate defects, and apparent diffusion coefficient (ADC) in nucleus pulposus. Twenty male volunteers underwent a lumbar spine examination at 1.5 T for anatomical imaging, diffusion weighted imaging, magnetic resonance angiography, and for T1 relaxation time quantification of contrast enhancement of intervertebral disc. Enhancement of the disc increased with degeneration. Disc space narrowing associated strongly with the enhancement (Pearson's correlation coefficient 0.46, P < 0.001). The enhancement rate in discs adjacent to Modic type 2 changes was 24%, adjacent to type 1/2 changes 58%, and 13% in the absence of Modic changes. Discs adjacent to endplate defects enhanced 32% compared to 10% of normal endplates. Lumbar artery narrowing or ADC in the disc were not associated with the enhancement. Increased enhancement of a degenerated disc is associated mostly with disc space narrowing and with the presence of degenerative endplate changes and endplate defects.
    MAGMA Magnetic Resonance Materials in Physics Biology and Medicine 10/2008; 22(2):101-9. · 1.88 Impact Factor
  • Article: Genetic factors are associated with modic changes in endplates of lumbar vertebral bodies.
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    ABSTRACT: A cross-sectional genotype-phenotype evaluation. To evaluate the genetic background to Modic changes in an occupational cohort. Modic changes are vertebral endplate changes visible in magnetic resonance imaging. Twin studies suggest that intervertebral disc degeneration may be primarily explained by genetic factors, but no data exist on genetic factors of Modic changes. Thirteen variations in 8 genes (COL9A2, COL9A3, COL11A2, IL1A, IL1B, IL6, MMP3, and VDR) were genotyped in an occupational cohort of 159 male train engineers and 69 male paper mill workers. All the subjects were scanned by magnetic resonance imaging and evaluated for Modic changes. Out of the 228 subjects, 128 (56%) were found to have Modic changes at one or more disc levels, exclusively of type I in 15%, of type II in 32%, and of both type I and type II in 10%. None of the single nucleotide polymorphisms was significantly associated with Modic changes when analyzed independently, but when gene-gene interactions were evaluated, interleukin-1A (IL1A) and matrix metalloproteinase-3 (MMP3) polymorphisms together were associated with type II Modic changes (OR = 3.2, 95% CI = 1.2-8.5; P = 0.038), as was the IL1 gene cluster together with the MMP3 polymorphism (OR = 8.14, 95% CI = 1.72-38.44; P = 0.008). This is the first study evaluating the role of genetic factors in relation to Modic changes. Genetic variations in the IL1 cluster and the MMP3 gene together were found to be significantly associated with type II Modic changes.
    Spine 06/2008; 33(11):1236-41. · 2.08 Impact Factor

Institutions

  • 2005–2013
    • University of Oulu
      • • Institute of Clinical Medicine
      • • Department of Medical Biochemistry and Molecular Biology
      • • Department of Physical Medicine and Rehabilitation
      Oulu, Oulu, Finland
  • 2003–2009
    • Oulu University Hospital
      Oulu, Oulu, Finland
  • 2008
    • Finnish Institute of Occupational Health
      Helsinki, Province of Southern Finland, Finland