PubMed Health⌕ Search

Biomedical subjects

Graeme Jones

Publications and source records attributed to Graeme Jones.

At least 19 recordsLinked to original sources
PubMed2007

A longitudinal study of the association between knee alignment and change in cartilage volume and chondral defects in a largely non-osteoarthritic population.

OBJECTIVE: It remains unclear whether malalignment of the knee is a cause of knee OA or a marker of disease progression. We investigated whether baseline malalignment of the knee predicts subsequent change in knee cartilage volume and chondral defects in subjects with and without radiographic knee osteoarthritis (OA). METHODS: A convenience sample of 315 male and female subjects (mean age 45 yrs, range 26-61) was followed up for a mean period of 2.4 years. Anatomic knee alignment was assessed on a standing anterior-posterior semiflexed view of the right knee and defined as the angle subtended by a line drawn through the midshaft of the femur with respect to one drawn through the midshaft of the tibia. T1-weighted fat saturation magnetic resonance imaging scans were performed on the same knee at baseline and followup for cartilage volume and chondral defects. RESULTS: Knee alignment was normally distributed in this sample with a mean of 178.2 degrees (SD 1.9 degrees). Fifty-five percent of subjects were < 178.5 degrees, while 14% were > 180 degrees. After adjustment for age, sex, body mass index, previous knee injury, and OA family history, neither category of alignment at baseline was associated with subsequent loss of lateral and medial tibial cartilage volume. Similarly, there was no association between malalignment and progression of chondral defects. The results remained the same when stratified by radiographic OA status. CONCLUSION: Our adequately powered study shows that baseline knee alignment is not associated with subsequent loss of cartilage volume or progression of chondral defects over 2 years. Further studies with a longterm followup are needed, but these results suggest malalignment is primarily a marker of disease progression.

Adult↗
PubMed2006

Effects of calcium supplementation on bone density in healthy children: meta-analysis of randomised controlled trials.

OBJECTIVES: To assess the effectiveness of calcium supplementation for improving bone mineral density in healthy children and to determine if any effect is modified by other factors and persists after supplementation stops. DESIGN: Meta-analysis. DATA SOURCES: Electronic bibliographic databases, hand searching of conference proceedings, and contacting authors for unpublished data. REVIEW METHODS: We included randomised placebo controlled trials of calcium supplementation in healthy children that lasted at least three months and had bone outcomes measured after at least six months of follow-up. Two reviewers independently extracted data and assessed quality. Meta-analyses predominantly used fixed effects models with outcomes given as standardised mean differences. RESULTS: We included 19 studies involving 2859 children. Calcium supplementation had no effect on bone mineral density at the femoral neck or lumbar spine. There was a small effect on total body bone mineral content (standardised mean difference 0.14, 95% confidence interval 0.01 to 0.27) and upper limb bone mineral density (0.14, 0.04 to 0.24). This effect persisted after the end of supplementation only at the upper limb (0.14, 0.01 to 0.28). There was no evidence that sex, baseline calcium intake, pubertal stage, ethnicity, or level of physical activity modified the effect. CONCLUSIONS: The small effect of calcium supplementation on bone mineral density in the upper limb is unlikely to reduce the risk of fracture, either in childhood or later life, to a degree of major public health importance.

Adolescent↗
PubMed2006

A longitudinal study of the effect of sex and age on rate of change in knee cartilage volume in adults.

OBJECTIVE: To describe the association between sex, age and rate of change in knee cartilage volume in adults. METHODS: A total of 325 subjects (mean age 45 yrs, range 26-61) was measured at baseline and approximately 2 yrs later. Knee cartilage volume and bone size were determined using T1-weighted fat saturation magnetic resonance imaging (MRI). Height, weight, body mass index and radiographic osteoarthritis (ROA) were measured by standard protocols. RESULTS: Knee cartilage volume decreased by 1.5-4.2% per annum. In multivariable analysis, females had higher rates of change per annum in knee cartilage volume than males (medial tibia: -3.5%, P < 0.001; lateral tibia: -2.6%, P < 0.001 and patella: -0.8%, P = 0.053). The sex difference first appeared at age 40 and became more marked with increasing age at the medial tibial site only (P = 0.039). Age was significantly associated with annual change in knee cartilage volume at all three sites (beta = -0.06 to -0.12%/yr, all P < 0.05), and these associations were stronger in females. With the exception of the medial site (beta = -0.05/yr, P = 0.117 for ROA exclusion, and beta = -0.06%/yr, P = 0.056 for ROA adjustment), the association with age did not change when subjects with ROA were excluded from analyses or after further adjustment for ROA. CONCLUSIONS: Within the age range we studied, knee cartilage volume declines at a faster rate with increasing age. This is partly mediated by ROA at the medial tibial site only. Furthermore, women have substantially higher knee cartilage loss than men, and these sex differences first appear at age 40 and become more marked with increasing age, which has implications for prevention of cartilage loss from middle age.

Adult↗
PubMed2006

Bone density interpretation and relevance in Caucasian children aged 9-17 years of age: insights from a population-based fracture study.

The interpretation of bone density measurement in children is difficult due to a number of factors including rapid change in body size and uncertain clinical significance of bone density in children. This study asked two questions. (1) Is there a preferred bone density measurement site or type for fracture risk in children? (2) What is the best way to interpret bone density in children? This population-based case control study included 321 upper limb fracture cases and 321 class- and sex- matched randomly selected controls. Bone density at the hip, spine, and total body (including the arm) was measured by a Hologic QDR2000 densitometer (Waltham, MA) and examined as bone area (BA), bone mineral content (BMC), bone mineral density (BMD), bone mineral apparent density (BMAD), and BMC/lean mass (BMCLM). The only dual-energy X-ray absorptiometry (DXA) variables that were consistently associated with fracture risk in both boys and girls were spine BMD and BMAD for total upper limb fractures, and spine and hip BMAD for wrist and forearm fractures. No significant associations were observed for BA and BMCLM and inconsistent associations for BMC and other BMD sites. Five-yr fracture risk varied from 15-24% depending on site and gender in a child with a Z-score of -3. In the controls, all DXA variables were associated with age, height, and weight, but the weakest associations were with BMAD. In conclusion, in this study the spine BMAD had the strongest and most consistent association with upper limb fracture risk in children. The associations with age and body size imply that age specific Z-scores will be the most convenient for interpretation of DXA measures in children. Five-yr wrist and forearm fracture risk has potential as a clinical endpoint of immediate relevance.

Absorptiometry, Photon↗
PubMed2006

Correlates of knee pain in older adults: Tasmanian Older Adult Cohort Study.

OBJECTIVE: To describe the association between chondral defects, bone marrow lesions, knee and hip radiographic osteoarthritis (OA), and knee pain. METHODS: Knee pain was assessed by the Western Ontario and McMaster Universities Osteoarthritis Index. T1- and T2-weighted fat saturation magnetic resonance imaging was performed on the right knee to assess chondral defects and subchondral bone marrow lesions. Radiography was performed on the right knee and hip and scored for radiographic OA. Body mass index (BMI) and knee extension strength were measured. RESULTS: A total of 500 randomly selected men and women participated. The prevalence of knee pain was 48%. In multivariable analysis, prevalent knee pain was significantly associated with medial tibial chondral defects (odds ratio [OR] 2.32, 95% confidence interval [95% CI] 1.02-5.28 for grade 3 versus grade 2 or less; OR 4.93, 95% CI 1.07-22.7 for grade 4 versus grade 2 or less), bone marrow lesions (OR 1.44, 95% CI 1.04-2.00 per compartment), and hip joint space narrowing (OR 1.36, 95% CI 1.07-1.73 per unit), as well as greater BMI and lower knee extension strength. It was not significantly associated with radiographic knee OA. These variables were also associated with more severe knee pain. In addition, there was a dose response association between knee pain and number of sites having grade 3 or 4 chondral defects (OR 1.39, 95% CI 1.12-1.73 per site), with all subjects having knee pain if all compartments of the knee had these defects. CONCLUSION: Knee pain in older adults is independently associated with both full and non-full-thickness medial tibial chondral defects, bone marrow lesions, greater BMI, and lower knee extension strength, but is not associated with radiographic knee OA. The association between radiographic hip OA and knee pain indicates that referred pain from the hip needs to be considered in unexplained knee pain.

Bone Marrow Diseases↗
PubMed2006

Correlates of knee pain in younger subjects.

The aim of this study was to describe clinical, structural and biochemical factors associated with knee pain in younger subjects. A cross-sectional convenience sample of 371 male and female subjects (mean age, 45 years, range 26-61) was studied. Knee pain was assessed by questionnaire. Chondral defects, cartilage volume, and bone area of the right knee were determined using T1-weighted fat saturation magnetic resonance imaging (MRI). X-ray was performed on the same knee for the assessment of radiographic features of osteoarthritis. The urinary C-terminal cross-linking telopeptide of type II collagen (CTX-II) was measured by enzyme-linked immunosorbent assay (ELISA). Height and weight were measured by standard protocols and body mass index (BMI) was calculated. The prevalence of knee pain was 35% in this sample. Chondral defect scores (particularly femoral and patellar but not tibial) were significantly associated with knee pain in a dose-response fashion (all p<0.01). Cartilage volume and bone area were not associated with knee pain in multivariate analysis in this sample. Urinary CTX-II was higher in subjects with knee pain (p=0.04), but this became nonsignificant after adjustment for BMI and osteophytes (both of which were significant) suggesting potential mechanisms of effect. In conclusion, knee pain is significantly associated with non-full thickness chondral defects (particularly femoral and patellar), osteophytes, CTX-II, and obesity but not other factors. MRI and biochemical measures can add to radiographs in defining unexplained knee pain in younger subjects.

Adult↗
PubMed2006

Natural history of knee cartilage defects and factors affecting change.

BACKGROUND: Knee cartilage defects may play an important role in early osteoarthritis, but little is known about their natural history. METHODS: Knee cartilage defect score (range, 0-4), cartilage volume, and bone surface area were determined using T1-weighted fat-saturated magnetic resonance imaging in 325 subjects (mean age, 45 years) at baseline and 2 years later. RESULTS: Thirty-three percent of the subjects had a worsening (>or=1-point increase) and 37% of the subjects had an improvement (>or=1-point decrease) in cartilage defect score in any knee compartment during 2.3 years. A worsening in cartilage defect score was significantly associated with female sex (odds ratio [OR], 3.09 and 3.64 in the medial and lateral tibiofemoral compartments) and baseline factors, including age (OR, 1.05 per year in the medial tibiofemoral compartment), body mass index (OR, 1.08 in the lateral tibiofemoral compartment), tibiofemoral osteophytes (OR, 6.22 and 6.04 per grade), tibial bone area (OR, 1.24 and 2.07 per square centimeter), and cartilage volume (OR, 2.91 and 1.71 per milliliter in the medial tibiofemoral and patellar compartments). An improvement in cartilage defect score had similar but reversed associations with these factors (except for sex), including a decrease in body mass index (OR, 1.23 in the medial tibiofemoral compartment). CONCLUSIONS: Knee cartilage defects are variable, and changes are associated with female sex, age, and body mass index. Increases are associated with baseline cartilage volume, bone size, and osteophytes, suggesting a role for these in the pathogenesis of cartilage defects. Interventions such as weight loss may improve knee cartilage defects.

Adult↗
PubMed2006

The effect on behavior and bone mineral density of individualized bone mineral density feedback and educational interventions in premenopausal women: a randomized controlled trial [NCT00273260].

BACKGROUND: Limited information is available on ways to influence osteoporosis risk in premenopausal women. This study tested four hypotheses regarding the effects of individualized bone density (BMD) feedback and different educational interventions on osteoporosis preventive behavior and BMD in pre-menopausal women, namely: that women are more likely to change calcium intake and physical activity if their BMD is low; that group education will be more efficacious at changing behavior than an information leaflet; that BMD feedback and group education have independent effects on behavior and BMD; and, that women who improve their physical activity or calcium intake will have a change in bone mass over 2 years that is better than those who do not alter their behavior. METHODS: We performed a 2-year randomized controlled trial of BMD feedback according to T-score and either an osteoporosis information leaflet or small group education in a population-based random sample of 470 healthy women aged 25-44 years (response rate 64%). Main outcome measures were dietary calcium intake, calcium supplement use, smoking behavior, physical activity, endurance fitness, lower limb strength and BMD. We used paired t-tests, one-way ANOVA and linear regression techniques for data analysis. RESULTS: Women who had feedback of low BMD had a greater increase in femoral neck BMD than those with normal BMD (1.6% p.a. vs. 0.7% p.a., p = 0.0001), but there was no difference in lumbar spine BMD change between these groups (0.1% p.a. vs. 0.08% p.a., p = 0.9). Both educational interventions had similar increases in femoral neck BMD (Leaflet = +1.0% p.a., Osteoporosis self-management course = + 1.3% p.a., p = 0.4). Femoral neck BMD change was only significantly associated with starting calcium supplements (1.3 % p.a, 95%CI +0.49, +2.17) and persistent self-reported change in physical activity levels (0.7% p.a., 95%CI +0.22, +1.22). CONCLUSION: Individualized BMD feedback combined with a minimal educational intervention is effective at increasing hip but not spine bone density in premenopausal women. The changes in behavior through which this was mediated are potentially important in the prevention of other diseases, thus measuring BMD at a young age may have substantial public health benefits, particularly if these changes are sustained.

Adult↗
PubMed2006

Genetic mechanisms of knee osteoarthritis: a population-based longitudinal study.

To describe the differences in knee structure and non-knee structural factors between offspring having at least one parent with a total knee replacement for severe primary knee osteoarthritis and age- and sex-matched controls with no family history of knee osteoarthritis, a population-based longitudinal study of 163 matched pairs (mean age 45 years, range 26 to 61) was performed at baseline and about 2 years later. Knee cartilage defect score (0 to 4), cartilage volume and bone size were determined with T1-weighted fat saturation magnetic resonance imaging. Body mass index (BMI), lower-limb muscle strength, knee pain, physical work capacity at 170 beats/minute (PWC170) and radiographic osteoarthritis were measured by standard protocols. In comparison with controls, offspring had higher annual knee cartilage loss (-3.1% versus -2.0% at medial tibial site, -1.9% versus -1.1% at lateral tibial site and -4.7% versus -3.7% at patellar site, all P < 0.05), a greater increase in medial cartilage defect score (+0.15 versus -0.01, P < 0.05) and a greater decline in PWC170 (-0.7 watts/kg versus -0.4 watts/kg, P < 0.01). There were no significant differences in change in BMI, lower-limb muscle strength, knee pain or tibial bone area between these two groups; however, the differences in knee cartilage loss and cartilage defect change decreased in magnitude and became non-significant after adjustment for baseline cartilage volume, tibial bone area, BMI and knee pain. This longitudinal study suggests that knee cartilage loss, change in cartilage defects and decrease in physical fitness all have roles in the development of knee osteoarthritis, which is most probably polygenic but may reflect a shared environment. Importantly, the cartilage changes are largely dependent on baseline differences in cartilage volume, tibial bone area, BMI and knee pain, suggesting that these factors might have a role in their initiation.

Adult↗
PubMed2006

Knee cartilage loss in symptomatic knee osteoarthritis over 4.5 years.

The objective of this study was to describe the rate of change in knee cartilage volume over 4.5 years in subjects with symptomatic knee osteoarthritis (OA) and to determine factors associated with cartilage loss. One hundred and five subjects were eligible for this longitudinal study. Subjects' tibial cartilage volume was assessed by magnetic resonance imaging (MRI) at baseline, at 2 years and at 4.5 years. Of 105 subjects, 78 (74%) completed the study. The annual percentage losses of medial and lateral tibial cartilage over 4.5 years were 3.7 +/- 4.7% (mean +/- SD; 95% confidence interval 2.7 to 4.8%) and 4.4 +/- 4.7% (mean +/- SD; 95% confidence interval 3.4 to 5.5%), respectively. Cartilage volume in each individual seemed to track over the study period, relative to other study participants. After multivariate adjustment, annual medial tibial cartilage loss was predicted by lesser severity of baseline knee pain but was independent of age, body mass index and structural factors. No factors specified a priori were associated with lateral cartilage volume rates of change. Tibial cartilage declines at an average rate of 4% per year in subjects with symptomatic knee OA. There was evidence to support the concept that tracking occurs in OA. This may enable the prediction of cartilage change in an individual. The only significant factor affecting the loss of medial tibial cartilage was baseline knee pain, possibly through altered joint loading.

Age Factors↗
PubMed2006

Familial, structural, and environmental correlates of MRI-defined bone marrow lesions: a sibpair study.

The aim of this study was to estimate the heritability and describe the correlates of bone marrow lesions in knee subchondral bone. A sibpair design was used. T2- and T1-weighted MRI scans were performed on the right knee to assess bone marrow lesions at lateral tibia and femora and medial tibia and femora, as well as chondral defects. A radiograph was taken on the same knee and scored for individual features of osteoarthritis (radiographic osteoarthritis; ROA) and alignment. Other variables measured included height, weight, knee pain, and lower-limb muscle strength. Heritability was estimated with the program SOLAR (Sequential Oligogenetic Linkage Analysis Routines). A total of 115 siblings (60 females and 55 males) from 48 families, representing 95 sib pairs, took part. The adjusted heritability estimates were 53 +/- 28% (mean +/- SEM; p = 0.03) and 65 +/- 32% (p = 0.03) for severity of bone marrow lesions at lateral and medial compartments, respectively. The estimates were reduced by 8 to 9% after adjustment for chondral defects and ROA (but not alignment). The adjusted heritability estimate was 99% for prevalent bone marrow lesions at both lateral and medial compartments. Both lateral and medial bone marrow lesions were significantly correlated with age, chondral defects, and ROA of the knee (all p < 0.05). Medial bone marrow lesions were also more common in males and were correlated with body mass index (BMI). Thus, bone marrow lesions have a significant genetic component. They commonly coexist with chondral defects and ROA but only share common genetic mechanisms to a limited degree. They are also more common with increasing age, male sex, and increasing BMI.

Adult↗
PubMed2006

Belimumab Human Genome Sciences/Cambridge Antibody Technology/GlaxoSmithKline.

Belimumab, the lead in a series of human monoclonal antibodies against the human protein B-lymphocyte stimulator (BLyS), is under development by Human Genome Sciences, Cambridge Antibody Technology and GlaxoSmithKline for the potential treatment of autoimmune diseases, including systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). By January 2006, belimumab had completed phase II clinical trials in SLE and RA; a phase III clinical SLE trial is scheduled to begin later this year.

Adult↗
PubMed2005

A compulsory experiential and inter-professional rural health subject for undergraduate students.

CONTEXT: The Australian University Departments of Rural Health (UDRH) program aims to improve the rural workforce through improving rural experiences of undergraduates, graduates and health professionals. The 10 UDRHs vary in the way they implement the UDRH Program. This article describes the development of a compulsory, experiential and inter-professional rural health subject in a medical curriculum by the UDRH at the University of Melbourne, Victoria, Australia. The key concepts, underpinning theory, processes, logistics and resources required to develop and implement the subject among a network of small towns and Indigenous communities are examined. METHODS: METHODS used included formative evaluation using a participatory research approach, including the examination of internal discussion papers, minutes of meetings and planning workshops, financial records and feedback from students, staff and preceptors. ISSUES: Students, staff and preceptors generally accept the value of the rural health module in professional training. However, they stress the need for explicit learning objectives, relevant content and engaging delivery. Students expressed some concern about the compulsory nature of the subject. Significant issues are capacity, quality, sustainability and managing expectations of government and communities. Capacity includes the availability of appropriate placements and preceptors who have the capacity and capability to teach or to be supported to teach. The availability of appropriate and affordable accommodation is important, as are the cost and safety of travel to and from placements. Sustainability of 'placements' and 'placement fatigue' must be managed with a combination of resources and preceptor training and support. Quality of placements is important and highlights a paradox in that, while academically rigorous teaching, research and clinical programs for students and preceptors are important for quality, they are mostly perceived as additional burdens by health service providers. Finally, the expectations and commitment of stakeholders, in particular governments and communities, for student placements must be realistic and backed with resources. LESSONS LEARNED: A compulsory experiential inter-professional subject for undergraduate students is possible but requires significant resources and commitment over the long term. The resources must include funding for: preceptor time, training and support; recruitment and retention of appropriately qualified academic clinicians; intersectoral strategies like improved public transport and safe roads; community and other stakeholder engagement to develop and maintain educational facilities. Last but not least, funding is essential to support the long-term evaluation and monitoring of the outcomes in terms of the quality and quantity of the rural workforce over time.

Australia↗
PubMed2005

Pharmacist-provided quantitative heel ultrasound screening for rural women at risk of osteoporosis.

BACKGROUND: Osteoporosis is underdiagnosed, and rural communities often have limited technical resources for the assessment of osteoporosis. OBJECTIVE: To evaluate the impact of a pharmacist, trained in the use of a portable heel ultrasound device, in screening elderly rural women for risk of osteoporosis and determine whether those found to be at risk seek further help and treatment from their general practitioner (GP) following screening. METHODS: Following promotion of the service, 345 women were recruited from 6 rural community pharmacies in Tasmania, Australia, and underwent quantitative heel ultrasound screening. Women were comprehensively educated on risk factors for osteoporosis and completed a calcium intake questionnaire. Results were forwarded to each woman's GP, and the participants were followed up 3 months later to assess outcomes from the screening procedure. RESULTS: Approximately 20% of women were shown to be at high risk for osteoporosis; 201 (58%) of these were referred to their GP for further assessment. Sixty-eight percent of women who were screened discussed their results with their GP, and 11% underwent further investigation. Over one-third of women screened began medication (30% calcium, 6% bisphosphonate, 6% vitamin D) for osteoporosis. CONCLUSIONS: Pharmacist-provided screening for osteoporosis in rural areas is a potentially useful method to identify women at risk for fracture and a convenient time point for discussion of preventive therapy.

Absorptiometry, Photon↗
PubMed2005

The effect of a fracture protocol on hospital prescriptions after minimal trauma fractured neck of the femur: a retrospective audit.

Effective therapies for the treatment of osteoporosis and fracture have been available for a number of years. Despite this, there are numerous reports indicating very low uptake rates in those admitted to hospital with fracture. The aim of this retrospective audit was to assess the impact of a fracture protocol on inpatient prescriptions of osteoporosis therapy. A fracture protocol was arrived at by consensus and was based on recommendations from the Australian Fracture Prevention Summit, which included specific advice on the commencement in hospital of calcium, vitamin D, synthetic estrogen receptor modulators (SERMs) and bisphosphonates. We studied subjects who were treated for fractured neck of the femur at Royal Hobart Hospital from March 2002 to March 2004 and included 161 prior to the start of the protocol and 93 after. As compared to the baseline period, subjects after the introduction of the protocol had higher rates of in-hospital prescription for any treatment (58 vs. 36%, P <0.01), calcium (51 vs. 26%, P <0.01), vitamin D (48 vs. 29%, P <0.01) and oral bisphosphonates (24 vs. 5%, P <0.01), but not SERMs as expected (1 vs. 1%, P =0.70). Additional factors affecting the decision to start any treatment included in-hospital death (OR 0.16, 95% CI 0.05-0.49), dementia (OR 0.39, 95% CI 0.21-0.74), a trend for female sex (OR 1.79, 95%CI 0.96-3.36), but not age. In conclusion, a structural approach to changing hospital policy from the top down is effective at substantially increasing the usage of effective therapy after fractured neck of the femur.

Aged↗
PubMed2005

Asymptomatic vertebral deformity as a major risk factor for subsequent fractures and mortality: a long-term prospective study.

UNLABELLED: In elderly men and women, asymptomatic vertebral deformity was found to be associated with subsequent risk of symptomatic fractures, particularly vertebral fracture, and increased risk of mortality after a fracture. INTRODUCTION: Vertebral deformity is associated with an increased risk of fracture and mortality. However, it is unclear whether the three events of vertebral deformity, fracture, and mortality are linked with each other and what role BMD plays in these linkages. MATERIALS AND METHODS: Vertebral deformity was determined from quantitative analysis of thoracolumbar spine X-rays in 300 randomly individuals (114 men and 186 women) 60 years of age (as of mid-1989), who were randomly selected from the prospective Dubbo Osteoporosis Epidemiology Study. Incidence of atraumatic fractures and subsequent mortality were ascertained from 1989 to 2003. Cox's proportional hazards model was used to determine the association between asymptomatic vertebral deformities, osteoporotic fractures, and risk of mortality. RESULTS: The prevalence of asymptomatic vertebral deformity was 31% in men and 17% in women. During the follow-up period, subjects with vertebral deformity had a significantly higher risk of any fracture than those without vertebral deformity (44% versus 29%; hazards ratio [HR], 2.2; 95% CI, 1.4-3.7), particularly symptomatic vertebral fracture (relative risk [RR], 7.4; 95% CI, 3.2-17.0). Mortality rate was highest after a symptomatic fracture among those with vertebral deformity (HR, 9.0; 95% CI, 3.1-26.0). These associations were independent of age, sex, and BMD. CONCLUSION: Vertebral deformity was a strong predictor of subsequent risk of fractures, particularly symptomatic vertebral fracture, and may modify fracture-associated mortality in both elderly men and women.

Aged↗
PubMed2005

Optimal sampling of MRI slices for the assessment of knee cartilage volume for cross-sectional and longitudinal studies.

BACKGROUND: MRI slices of 1.5 mm thickness have been used in both cross sectional and longitudinal studies of osteoarthritis, but is difficult to apply to large studies as most techniques used in measuring knee cartilage volumes require substantial post-image processing. The aim of this study was to determine the optimal sampling of 1.5 mm thick slices of MRI scans to estimate knee cartilage volume in males and females for cross-sectional and longitudinal studies. METHODS: A total of 150 subjects had a sagittal T1-weighted fat-suppressed MRI scan of the right knee at a partition thickness of 1.5 mm to determine their cartilage volume. Fifty subjects had both baseline and 2-year follow up MRI scans. Lateral, medial tibial and patellar cartilage volumes were calculated with different samples from 1.5 mm thick slices by extracting one in two, one in three, and one in four to compare to cartilage volume and its rate of change. Agreement was assessed by means of intraclass correlation coefficient (ICC) and Bland & Altman plots. RESULTS: Compared to the whole sample of 1.5 mm thick slices, measuring every second to fourth slice led to very little under or over estimation in cartilage volume and its annual change. At all sites and subgroups, measuring every second slice had less than 1% mean difference in cartilage volume and its annual rate of change with all ICCs > or = 0.98. CONCLUSION: Sampling alternate 1.5 mm thick MRI slices is sufficient for knee cartilage volume measurement in cross-sectional and longitudinal epidemiological studies with little increase in measurement error. This approach will lead to a substantial decrease in post-scan processing time.

Aged↗