Karen A Beattie

McMaster University, Hamilton, Ontario, Canada

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Publications (46)130.78 Total impact

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    ABSTRACT: Objectives. To determine (1) whether intramuscular adipose tissue (IntraMAT) differs between women with and without type 2 diabetes and (2) the association between IntraMAT and mobility and strength. Methods. 59 women ≥ 65 years with and without type 2 diabetes were included. A 1-Tesla MRI was used to acquire images of the leg. Timed-up-and-go (TUG) and grip strength were measured. Regression was used to determine associations between the following: (1) type 2 diabetes and IntraMAT (covariates: age, ethnicity, BMI, waist : hip ratio, and energy expenditure), (2) IntraMAT and TUG (covariates: diabetes, age, BMI, and energy expenditure), and (3) IntraMAT and grip strength (covariates: diabetes, age, height, and lean mass). Results. Women with diabetes had more IntraMAT. After adjustment, IntraMAT was similar between groups (diabetes mean [SD] = 13.2 [1.4]%, controls 11.8 [1.3]%, P = 0.515). IntraMAT was related to TUG and grip strength, but the relationships became nonsignificant after adjustment for covariates (difference/percent IntraMAT [95% CI]: TUG = 0.041 seconds [-0.079-0.161], P = 0.498, grip strength = -0.144 kg [-0.335-0.066], P = 0.175). Conclusions. IntraMAT alone may not be a clinically important predictor of functional mobility and strength; however, whether losses in functional mobility and strength are promoted by IntraMAT accumulation should be explored.
    Journal of aging research 01/2015; 2015:872726.
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    ABSTRACT: To determine the degree to which muscle density and fractures are explained by inter and intramuscular fat (IMF). Women ⋝50 years of age (Hamilton, ON, Canada) had peripheral magnetic resonance imaging and peripheral quantitative computed tomography scans at 66% of the tibial length. Muscle on computed tomography images was segmented from subcutaneous fat and bone using fixed thresholds, computing muscle density. IMF was segmented from muscle within magnetic resonance images using a region-growing algorithm, computing IMF volume. Fracture history over the last 14 years was obtained. Odds ratios for fractures were determined for muscle density, adjusting for IMF volume, total hip BMD, age and body mass index. Women with a history of fractures were older (N=32, age:75.6±8.3 years) than those without (N=39, age: 67.0±5.2 years) (<0.01). IMF volume explained 49.3% of variance in muscle density (p<0.001). Odds for fractures were associated with lower muscle density even after adjusting for IMF volume but were attenuated after adjusting for age. Muscle adiposity represents only 50% of the muscle density measurement. Properties of muscle beyond its adiposity may be related to fractures, but larger and prospective studies are needed to confirm these associations.
    Journal of musculoskeletal & neuronal interactions 12/2014; 14(4):401-10. · 2.40 Impact Factor
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    ABSTRACT: Severe constant and intermittent knee pain are associated with "unacceptable" symptoms in older adults with osteoarthritis (OA) [22]. We hypothesized that constant and intermittent pain would be independently related to physical function, with intermittent knee pain being a better predictor of future declines in physical function in early symptomatic knee OA. This study included men (n = 189) and women (n = 133) with radiographic, unilateral knee OA, observed using data from the Osteoarthritis Initiative (OAI). Pain types were measured using the Intermittent and Constant Osteoarthritis Pain (ICOAP) scale. Physical function was measured using the Western Ontario and McMaster Universities Arthritis Index (WOMAC-PF) and Knee Injury and Osteoarthritis Outcome Score (KOOS-FSR) and physical performance tests. High baseline intermittent (B = 0.277; p = 0.001) and constant (B = 0.252; p = 0.001) knee pain were related to poor WOMAC-PF. Increased constant (B = 0.484; p = 0.001) and intermittent (B = 0.104; p = 0.040) pain were related to 2-year decreased WOMAC-PF. High baseline intermittent knee pain predicted poor KOOS-FSR at year 2 (B = -0.357; p = 0.016). Increased constant pain was related to decreased chair stand test performance over 2 years in women (B = 0.077; p = 0.001). High baseline intermittent pain was related to poor performance on repeated chair stands (B = 0.035; p = 0.021), while baseline constant pain was related to poor 400-m walk performance in women (B = 0.636; p = 0.047). Intermittent and constant knee pain were independent factors in self-perceived physical function and were important predictors of future limitations in physical function. Identifying intermittent and constant pain in early symptomatic OA may allow patients to adopt strategies to prevent worsening pain and future declines in physical function.
    Clinical Rheumatology 11/2014; · 1.77 Impact Factor
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    ABSTRACT: In vivo peripheral quantitative computed tomography (pQCT) and peripheral magnetic resonance imaging (pMRI) modalities can measure apparent bone microstructure at resolutions 200 μm or higher. However, validity and in vivo test-retest reproducibility of apparent bone microstructure have yet to be determined on 1.0 T pMRI (196 μm) and pQCT (200 μm). This study examined 67 women with a mean age of 74 ± 9 yr and body mass index of 27.65 ± 5.74 kg/m2, demonstrating validity for trabecular separation from pMRI, cortical thickness, and bone volume fraction from pQCT images compared with high-resolution pQCT (hr-pQCT), with slopes close to unity. However, because of partial volume effects, cortical and trabecular thickness of bone derived from pMRI and pQCT images matched hr-pQCT more only when values were small. Short-term reproducibility of bone outcomes was highest for bone volume fraction (BV/TV) and densitometric variables and lowest for trabecular outcomes measuring microstructure. Measurements at the tibia for pQCT images were more precise than at the radius. In part I of this 3-part series focused on trimodality comparisons of precision and validity, it is shown that pQCT images can yield valid and reproducible apparent bone structural outcomes, but because of longer scan time and potential for more motion, the pMRI protocol examined here remains limited in achieving reliable values.
    Journal of Clinical Densitometry 08/2014; · 1.60 Impact Factor
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    ABSTRACT: Part II of this 3-part series demonstrated 1-yr precision, standard error of the estimate, and 1-yr least significant change for volumetric bone outcomes determined using peripheral (p) quantitative computed tomography (QCT) and peripheral magnetic resonance imaging (pMRI) modalities in vivo. However, no clinically relevant outcomes have been linked to these measures of change. This study examined 97 women with mean age of 75 ± 9 yr and body mass index of 26.84 ± 4.77 kg/m2, demonstrating a lack of association between fragility fractures and standard deviation, least significant change and standard error of the estimate-based unit differences in volumetric bone outcomes derived from both pMRI and pQCT. Only cortical volumetric bone mineral density and cortical thickness derived from high-resolution pQCT images were associated with an increased odds for fractures. The same measures obtained by pQCT erred toward significance. Despite the smaller 1-yr and short-term precision error for measures at the tibia vs the radius, the associations with fractures observed at the radius were larger than at the tibia for high-resolution pQCT. Unit differences in cortical thickness and cortical volumetric bone mineral density able to yield a 50% increase in odds for fractures were quantified here and suggested as a reference for future power computations.
    Journal of Clinical Densitometry 08/2014; · 1.60 Impact Factor
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    ABSTRACT: The previous article in this 3-part series demonstrated short-term precision and validity for volumetric bone outcome quantification using in vivo peripheral (p) quantitative computed tomography (pQCT) and magnetic resonance imaging (MRI) modalities at resolutions 200 μm or higher. However, 1-yr precision error and clinically significant references are yet to be reported for these modalities. This study examined 59 women with mean age of 75 ± 9 yr and body mass index of 26.84 ± 4.77 kg/m2, demonstrating the lowest 1-yr precision error, standard errors of the estimate, and least significant change values for high-resolution (hr) pQCT followed by pQCT, and 1.0-T pMRI for all volumetric bone outcomes except trabecular number. Like short-term precision, 1-yr statistics for trabecular separation were similar across modalities. Excluding individuals with a previous history of fragility fractures, or who were current users of antiresorptives reduced 1-yr change for bone outcomes derived from pQCT and pMR images, but not hr-pQCT images. In Part II of this 3-part series focused on trimodality comparisons of 1-yr changes, hr-pQCT was recommended to be the prime candidate for quantifying change where smaller effect sizes are expected, but pQCT was identified as a feasible alternative for studies expecting larger changes.
    Journal of Clinical Densitometry 08/2014; · 1.60 Impact Factor
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    ABSTRACT: Permanent joint damage is a major consequence of rheumatoid arthritis (RA), the most common and destructive form of inflammatory arthritis. In aggressive disease, joint damage can occur within 6 months from symptom onset. Early, intensive treatment with conventional and biologic disease-modifying anti-rheumatic drugs (DMARDs) can delay the onset and progression of joint damage. The primary objective of the study is to investigate the value of magnetic resonance imaging (MRI) or radiography (X-ray) over standard of care as tools to guide DMARD treatment decision-making by rheumatologists for the care of RA.
    Trials 07/2014; 15(1):268. · 2.12 Impact Factor
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    ABSTRACT: In peripheral quantitative computed tomography scans of the calf muscles, segmentation of muscles from subcutaneous fat is challenged by muscle fat infiltration. Threshold-based edge detection segmentation by manufacturer software fails when muscle boundaries are not smooth. This study compared the test-retest precision error for muscle-fat segmentation using the threshold-based edge detection method vs manual segmentation guided by the watershed algorithm. Three clinical populations were investigated: younger adults, older adults, and adults with spinal cord injury (SCI). The watershed segmentation method yielded lower precision error (1.18%–2.01%) and higher (p < 0.001) muscle density values (70.2 ± 9.2 mg/cm3) compared with threshold-based edge detection segmentation (1.77%–4.06% error, 67.4 ± 10.3 mg/cm3). This was particularly true for adults with SCI (precision error improved by 1.56% and 2.64% for muscle area and density, respectively). However, both methods still provided acceptable precision with error well under 5%. Bland-Altman analyses showed that the major discrepancies between the segmentation methods were found mostly among participants with SCI where more muscle fat infiltration was present. When examining a population where fatty infiltration into muscle is expected, the watershed algorithm is recommended for muscle density and area measurement to enable the detection of smaller change effect sizes.
    Journal of Clinical Densitometry 07/2014; · 1.60 Impact Factor
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    ABSTRACT: Objective To determine the extent to which knee extensor strength and power explain variance in knee adduction moment (KAM) peak and impulse in clinical knee osteoarthritis (OA).Methods Fifty-three adults (mean ± SD age 61.6 ± 6.3 years, 11 men) with clinical knee OA participated. The KAM waveform was calculated from motion and force data and ensemble averaged from 5 walking trials. The KAM peak was normalized to body mass (Nm/kg). The mean KAM impulse reflected the mean total medial knee load during stride (Nm × seconds). For strength, the maximum knee extensor moment attained from maximal voluntary isometric contractions (MVIC) was normalized to body mass (Nm/kg). For power, the maximum knee extensor power during isotonic contractions, with the resistance set at 25% of MVIC, was normalized to body mass (W/kg). Covariates included age, sex, knee pain on the Knee Injury and Osteoarthritis Outcome Score, gait speed, and body mass index (BMI). Relationships of the KAM peak and impulse with strength and power were examined using sequential stepwise forward linear regressions.ResultsCovariates did not explain variance in the KAM peak. While extensor strength did not, peak knee extensor power explained 8% of the variance in the KAM peak (P = 0.02). Sex and BMI explained 24% of the variance in the KAM impulse (P < 0.05). Sex, BMI, and knee extensor power explained 31% of the variance in the KAM impulse (P = 0.02), with power contributing 7% (P < 0.05).Conclusion Knee extensor power was more important than isometric knee strength in understanding medial knee loads during gait.
    Arthritis Care & Research. 05/2014; 66(5).
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    ABSTRACT: Canadian guidelines recommend either the FRAX or the Canadian Association of Radiologists and Osteoporosis Canada (CAROC) fracture risk assessment tools to report 10-yr fracture risk as low (<10%), moderate (10%-20%) or high (>20%). It is unknown whether one reporting system is more effective in helping family physicians (FPs) identify individuals who require treatment. Individuals ≥50 yr old with a distal radius fracture and no previous osteoporosis diagnosis or treatment were recruited. Participants underwent a dual-energy x-ray absorptiometry scan and answered questions about fracture risk factors. Participants' FPs were randomized to receive either a FRAX report or the standard CAROC-derived bone mineral density report currently used by the institution. Only the FRAX report included statements regarding treatment recommendations. Within 3 mo, all participants were asked about follow-up care by their FP, and treatment recommendations were compared with an osteoporosis specialist. Sixty participants were enrolled (31 to FRAX and 29 to CAROC). Kappa statistics of agreement in treatment recommendation were 0.64 for FRAX and 0.32 for bone mineral density. The FRAX report was preferred by FPs and resulted in better postfracture follow-up and treatment that agreed more closely with a specialist. Either the clear statement of fracture risk or the specific statement of treatment recommendations on the FRAX report may have supported FPs to make better treatment decisions.
    Journal of Clinical Densitometry 10/2013; · 1.60 Impact Factor
  • Osteoarthritis and Cartilage 04/2013; 21:S44. · 4.66 Impact Factor
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    ABSTRACT: BACKGROUND: The risk of experiencing an osteoporotic fracture is greater for adults with type 2 diabetes despite higher than normal bone mineral density (BMD). In addition to BMD, trabecular bone microarchitecture contributes to bone strength, but is not assessed using conventional BMD measurement by dual x-ray absorptiometry (DXA). The aim of this study was to compare two year changes in trabecular bone microarchitecture in women with and without type 2 diabetes. METHODS: We used a 1 Tesla magnetic resonance imaging (MRI) scanner to acquire axial images (resolution 195mum x 195mum x 1000mum) of the distal radius. We report the change in the number and size of trabecular bone holes, bone volume fraction (BVTV), trabecular thickness (Tb.Th), number (Tb.N) and separation (Tb.Sp), endosteal area, nodal and branch density for each group. Lumbar spine and proximal femur BMD were measured with DXA (Hologic, Discovery QDR4500A) at baseline and follow-up. Using a multivariable linear regression model, we evaluated whether the percent change in the trabecular bone microarchitecture variables differed between women with and without type 2 diabetes. RESULTS: Of the 54 participants at baseline with valid MRI image sets, 37 participants (baseline mean [SD] age, 70.8 [4.4] years) returned for follow-up assessment after 25.4 [1.9] months. Lumbar spine BMD was greater for women with diabetes compared to without diabetes at both baseline and follow-up. After adjustment for ethnicity, women with diabetes had a higher percent increase in number of trabecular bone holes compared to controls (10[1] % versus -7 [2]%, p=0.010), however results were no longer significant after adjustment for multiple comparisons (p=0.090). There were no differences in the change in other trabecular bone microarchitecture variables between groups. CONCLUSION: There were no differences in percent change in trabecular bone microarchitecture variables over two years in women with type 2 diabetes compared to women without diabetes. This study provides feasibility data, which will inform future trials assessing change in trabecular bone microarchitecture in women with type 2 diabetes. Larger studies using higher resolution imaging modalities that can assess change in trabecular and cortical bone compartments in women with type 2 diabetes are needed.
    BMC Musculoskeletal Disorders 03/2013; 14(1):114. · 1.90 Impact Factor
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    ABSTRACT: PURPOSE: The purpose of this study was to determine whether trabecular bone mineralization differed in adults with type 2 diabetes compared to adults without type 2 diabetes. METHODS: Proximal femur specimens were obtained following a total hip replacement procedure from men and women≥65years of age with and without type 2 diabetes. A scanning electron microscope was used for quantitative backscattered electron imaging (qBEI) analysis of trabecular bone samples from the femoral neck. Gray scale images (pixel size=5.6μm2) were uploaded to ImageJ software and gray level (GL) values were converted to calcium concentrations (weight [wt] % calcium [Ca]) using data obtained with energy dispersive x-ray spectrometry. The following bone mineralization density distribution (BMDD) outcomes were collected: the weighted mean bone calcium concentration (CaMEAN), the most frequently occurring bone calcium concentration (CaPEAK) and mineralization heterogeneity (CaWIDTH). Differences between groups were assessed using the Student's t-test for normally distributed data and Mann-Whitney U-test for non-normally distributed data. An alpha value of<0.05 was considered significant. RESULTS: Thirty-five Caucasian participants were recruited (mean±standard deviation [SD] age, 75.5±6.5years): 14 adults with type 2 diabetes (years since type 2 diabetes diagnosis, 13.5±7.4years) and 21 adults without type 2 diabetes. In the adults with type 2 diabetes, bone CaMEAN was 4.9% greater (20.36±0.98 wt % Ca versus 19.40±1.07 wt % Ca, p=0.015) and CaWIDTH was 9.4% lower (median [interquartile range] 3.55 [2.99-4.12] wt % Ca versus 3.95±0.71 wt % Ca, p<0.001) compared to controls. There was no between-group difference in CaPEAK (21.12±0.97 wt % Ca for type 2 diabetes versus 20.44±1.30 wt % Ca for controls, p=0.121). CONCLUSION: The combination of elevated mean calcium concentration in bone and lower mineralization heterogeneity in adults with type 2 diabetes may have deleterious effects on the biomechanical properties of bone. These microscopic alterations in bone mineralization, which may be mediated by suppressed bone remodeling, further elucidate higher fracture risk in adults with type 2 diabetes.
    Bone 01/2013; · 4.46 Impact Factor
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    ABSTRACT: OBJECTIVES: To determine the extent to which thigh intermuscular fat (IMF) and quadriceps muscle (QM) volumes explained variance in knee extensor strength and physical performance in women with (ROA) and without (NROA) radiographic knee osteoarthritis. METHODS: Baseline data from 125 women in the Osteoarthritis Initiative, ò50 years, with or at risk for ROA were included. Knee extensor strength was measured using a fixed force transducer, normalized to body mass (N/kg). Physical performance was the time required for five repeated chair stands (s). The IMF and QM volumes, normalized to height (cm(3) /m), were yielded from analyses of T1-weighted axial magnetic resonance images of the mid-thigh. Mean IMF and QM volumes, extensor strength and physical performance were compared between ROA and NROA, controlling for age. Hierarchical multiple regressions determined whether IMF and QM volumes were related to strength and performance after controlling for age, radiographic OA status (yes/no), alignment and pain. RESULTS: Compared to ROA, the NROA were stronger and performed chair stands faster (p<0.05). After adjusting for age, NROA had less IMF (61.1 ± 20.3 cm(3) /m) compared to ROA (72.0 ± 25.0 cm(3) /m, p<0.05). In the entire sample, 21.1% of variance in knee extensor strength was explained by alignment, pain and IMF. A model explaining 13.4% of variance in physical performance included OA status and IMF. QM volume was unrelated to strength and physical performance. Conclusions: Intermuscular fat volume explained a small amount of variance in knee extensor strength and physical performance among women with, or at risk for ROA. © 2012 by the American College of Rheumatology.
    Arthritis Care and Research 01/2013; 65(1):44-52. · 4.04 Impact Factor
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    ABSTRACT: Compare in vitro and in vivo characteristics and clinical outcomes of brand and generic alendronate. Relevant search terms were input into Medline ("alendronate" AND "generic" up to August 5, 2013) and any abstracts deemed possibly relevant selected for full paper review and abstraction. Multicentre, randomized, placebo-controlled Phase III clinical trials of substantial size and duration have established the anti-fracture efficacy and safety of brand amino-bisphosphonates. For regulatory approval, generic versions of brand drugs need to demonstrate bioequivalence in young, healthy volunteers and have similar dissolution times. While the potency and amount of active drug within generic formulations must be identical to the brand, differences are permitted in the excipients. Significant differences in tablet disintegration time among different versions of generic and brand alendronate have been reported. Rapidly disintegrating alendronate pills may increase oesophageal bioadhesion and adverse event risk. Oesophageal-bound alendronate or slow disintegrating alendronate tablets may be made inert and ineffective by subsequently ingested food or drink. Investigations have reported a lower persistence to therapy with generic brands of alendronate as compared to brand bisphosphonates and patients switched from brand to generic alendronate have increased adverse event rates and losses in bone mineral density. Numerous differences exist between brand and generic alendronate including: disintegration time, bioadhesion to the oesophagus, patient persistence to therapy, adverse event incidence, and maintenance of bone mineral density. Generic forms of alendronate warrant closer clinical study before they are ascribed the clinical effectiveness and tolerability of brand alendronate.
    SpringerPlus 01/2013; 2(1):550.
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    Karen A. Beattie, Norma J. MacIntyre, Alfred Cividino
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    ABSTRACT: Objective To evaluate the sensitivity and specificity of the Gait, Arms, Legs, and Spine (GALS) examination to screen for signs and symptoms of rheumatoid arthritis (RA) when used by family physicians and nurse practitioners. Methods Participating health care professionals (2 rheumatologists, 3 family physicians, and 3 nurse practitioners) were trained to perform the GALS examination by viewing an instructional DVD and attending a training workshop. One week after training, the health care professionals performed the GALS examination on 20 individuals with RA and 21 individuals without RA. All participants were recruited through 2 rheumatology practices, and each participant was assessed by 4 health care professionals. The health care professionals were asked to record whether observed signs and symptoms were potentially consistent with a diagnosis of RA. The health care professionals understood the study objective to be their agreement on GALS findings among one another and were unaware that one-half of the participants had RA. Sensitivity and specificity were calculated to determine the ability of the GALS examination to screen for RA using the rheumatologist as the standard for comparison. ResultsSensitivity and specificity values varied from 60–100% and 70–82%, respectively, for the 3 family physicians, and 60–90% and 73–100%, respectively, for the 3 nurse practitioners. Conclusion Following a very short training period, family physicians and nurse practitioners appeared to be able to use the GALS examination as a screening tool for RA signs and symptoms, particularly for identifying an individual with positive results who will benefit from further investigation or rheumatology referral.
    Arthritis Care & Research. 12/2012; 64(12).
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    Archives of physical medicine and rehabilitation 10/2012; 93(10):1882. · 2.18 Impact Factor
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    ABSTRACT: Strontium ranelate is an approved pharmacotherapy for osteoporosis in Europe and Australia, but not in Canada or the United States. Strontium citrate, an alternative strontium salt, however, is available for purchase over-the-counter as a nutritional supplement. The effects of strontium citrate on bone are largely unknown. The study's objectives were 1) to quantify bone strontium accumulation in female Sprague Dawley rats administered strontium citrate (N=7) and compare these levels to rats administered strontium ranelate (N=6) and vehicle (N=6) over 8weeks, and 2) to verify an in vivo X-ray fluorescence spectroscopy (XRF) system for measurement of bone strontium in the rat. Daily doses of strontium citrate and strontium ranelate were determined with the intention to achieve equivalent amounts of elemental strontium. However, post-hoc analyses of each strontium compound conducted using energy dispersive spectrometry microanalysis revealed a higher elemental strontium concentration in strontium citrate than strontium ranelate. Bone strontium levels were measured at baseline and 8weeks follow-up using a unique in vivo XRF technique previously used in humans. XRF measurements were validated against ex vivo measurements of bone strontium using inductively coupled plasma mass spectrometry. Weight gain in rats in all three groups was equivalent over the study duration. A two-way ANOVA was conducted to compare bone strontium levels amongst the three groups. Bone strontium levels in rats administered strontium citrate were significantly greater (p<0.05) than rats administered strontium ranelate and vehicle. ANCOVA analyses were performed with Sr dose as a covariate to account for differences in strontium dosing. The ANCOVA revealed differences in bone strontium levels between the strontium groups were not significant, but that bone strontium levels were still very significantly greater than vehicle.
    Bone 09/2012; 52(1):63-69. · 4.46 Impact Factor
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    ABSTRACT: Adults with type 2 diabetes mellitus (DM) have an elevated fracture risk despite normal areal bone mineral density (aBMD). The study objective was to compare trabecular bone microarchitecture of postmenopausal women with type 2 DM and women without type 2 DM. An extremity 1T magnetic resonance imaging system was used to acquire axial images (195 × 195 × 1,000 μm(3) voxel size) of the distal radius of women recruited from outpatient clinics or by community advertisement. Image segmentation yielded geometric, topologic, and stereologic outcomes, i.e., number and size of trabecular bone network holes (marrow spaces), endosteal area, trabecular bone volume fraction, nodal and branch density, and apparent trabecular thickness, separation, and number. Lumbar spine (LS) and proximal femur BMD were measured with dual x-ray absorptiometry. Microarchitectural differences were assessed using linear regression and adjusted for percent body fat, ethnicity, timed up-and-go test, Charlson Index, and calcium and vitamin D intake; aBMD differences were adjusted for body mass index (BMI). Women with type 2 DM (n = 30, mean ± SD age 71.0 ± 4.8 years) had larger holes (+13.3%; P = 0.001) within the trabecular bone network than women without type 2 DM (n = 30, mean ± SD age 70.7 ± 4.9 years). LS aBMD was greater in women with type 2 DM; however, after adjustment for BMI, LS aBMD did not differ between groups. In women with type 2 DM, the average hole size within the trabecular bone network at the distal radius is greater compared to controls. This may explain the elevated fracture risk in this population.
    Arthritis care & research. 01/2012; 64(1):83-91.
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    ABSTRACT: To determine the feasibility of conducting a randomized controlled trial assessing the effect of low-intensity pulsed ultrasound (US) therapy on cartilage repair in patients with mild to moderate knee osteoarthritis (OA). Pilot, double-blinded, randomized placebo-controlled trial with 2-months follow-up. Rehabilitation research facility. Adults (N=27; ≥45y) with grades 1 or 2 of medial joint space narrowing (Osteoarthritis Research Society International atlas) due to knee OA were randomly allocated to receive active (n=14) or sham (n=13) US therapy. Four participants withdrew for personal reasons. Twenty-four sessions of active (20% duty cycle, 1MHz, average temporal intensity: 0.2W/cm(2), therapeutic dose: 112.5J/cm(2)) or sham (no sound-head crystal) US therapy. Success of recruitment and adherence rates were established by a priori criteria. Effect on cartilage repair was assessed by measuring cartilage volume and thickness and scoring cartilage injury, subchondral cyst formation, and bone marrow lesions on magnetic resonance images. Patient recruitment and adherence rates were successful. No significant age-adjusted differences were seen between groups in the cartilage repair outcomes. Age-adjusted analyses, including only subjects who attended 20 sessions or more, showed an increase in medial tibia cartilage thickness in the active US therapy group (90μm; 95% confidence interval, 1-200; P=.05). Conducting a randomized controlled trial to assess the effects of US therapy on the cartilage repair in people with mild to moderate knee OA is feasible. However, further pilot studies are needed to determine the optimal US dose and application parameters before designing a full trial.
    Archives of physical medicine and rehabilitation 01/2012; 93(1):35-42. · 2.18 Impact Factor