Helen Cooley

University of Tasmania, Newnham, Tasmania, Australia

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Publications (7)45.79 Total impact

  • Article: Knee and hip radiographic osteoarthritis predict total hip bone loss in older adults: a prospective study.
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    ABSTRACT: The relationship between osteoarthritis (OA) and osteoporosis remains controversial. This study was designed to determine the association between hip and knee radiographic OA and change in total hip bone mineral density (BMD) over 2.6 years. A total of 867 population-based randomly selected subjects (mean age 62 years, range 51 to 80 years, and 49% female) were included. Hip and knee joint space narrowing (JSN, 0 to 3) and osteophytes (0 to 3) in both lower limbs was assessed using Altman's atlas. Total hip BMD was measured by dual-energy X-ray absorptiometry (DXA). We found that radiographic OA (score of JSN or osteophytes > 0) was common in this sample (hip 45%, knee 68%). In multivariable analyses, percentage change in total hip BMD per year was predicted by right and left hip axial JSN (beta = -0.25% and -0.29% per grade, respectively, both p < .05), right hip superior femoral osteophytes (grades 2 and 3 versus 0: beta = -1.60, p < .05), combined right and left knee tibiofemoral JSN (beta = -0.06 per grade from grades 0 to 12, p < .05), and osteophytes (beta = -0.06 per grade from grades 0 to 14, p < .05) independent of each other and joint pain. In conclusion, older subjects with radiographic hip and knee OA have higher total hip bone loss over 2.6 years regardless of symptoms, suggesting that consideration should be given to the monitoring of bone mass in these subjects.
    Journal of bone and mineral research: the official journal of the American Society for Bone and Mineral Research 10/2009; 25(4):858-65. · 6.04 Impact Factor
  • Article: Correlates of knee pain in older adults: Tasmanian Older Adult Cohort Study.
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    ABSTRACT: To describe the association between chondral defects, bone marrow lesions, knee and hip radiographic osteoarthritis (OA), and knee pain. 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. 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. 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.
    Arthritis & Rheumatism 05/2006; 55(2):264-71. · 7.87 Impact Factor
  • Article: Natural history of knee cartilage defects and factors affecting change.
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    ABSTRACT: Knee cartilage defects may play an important role in early osteoarthritis, but little is known about their natural history. 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. 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). 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.
    Archives of Internal Medicine 03/2006; 166(6):651-8. · 11.46 Impact Factor
  • Article: The genetic contribution and relevance of knee cartilage defects: case-control and sib-pair studies.
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    ABSTRACT: To describe the differences in knee cartilage defects between offspring of subjects with at least one parent with a total knee replacement for severe primary knee osteoarthritis (OA) and controls; and to estimate the heritability of knee cartilage defects in sib-pairs. Population based, case-control study of 186 matched pairs (mean age 45 yrs, range 26-61) and sib-pair study of 128 subjects from 51 families (115 sib-pairs) within the case-control study. Knee cartilage defect scores (0-4) and prevalence (a cartilage defect score > or = 2) were assessed at the patellar, tibial, and femoral sites by processing images acquired using T1 weighted fat-saturated magnetic resonance imaging. Heritability was estimated using the SOLAR genetic analysis program. The prevalence of knee cartilage defects was surprisingly high (50% scored > or = 2 in any site). Compared to controls, offspring had higher knee cartilage defect scores and prevalence in tibiofemoral (4.39 vs 4.01, p = 0.003; 41% vs 28%, p = 0.009), patellar (1.32 vs 1.10, p = 0.031; 35% vs 26%, p = 0.075), and whole (5.71 vs 5.10, p = 0.002; 57% vs 42%, p = 0.007) compartments. These all became nonsignificant after adjustment for knee pain and radiographic OA. In the sib-pair component, knee cartilage defects had heritability for scores and prevalence, respectively, of 38% (p = 0.072) and 47% (p = 0.082) for tibiofemoral, 52% (p = 0.009) and 78% (p = 0.025) for patellar, and 43% (p = 0.038) and 68% (p = 0.072) for the whole compartments. These estimates became weaker at tibiofemoral and whole compartments after adjustment for bone size, knee pain, and radiographic OA. Knee cartilage defects are common, have a genetic component that is linked to the genetic contribution to knee pain and bone size, and may have a role in the genetic pathogenesis of knee OA.
    The Journal of Rheumatology 10/2005; 32(10):1937-42. · 3.69 Impact Factor
  • Article: Factors associated with hip cartilage volume measured by magnetic resonance imaging: the Tasmanian Older Adult Cohort Study.
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    ABSTRACT: To compare associations between anthropometric and lifestyle factors and femoral head cartilage volume/thickness and radiographic features of osteoarthritis (OA) and to provide evidence of construct validity for magnetic resonance imaging (MRI) assessment of femoral cartilage volume and thickness. We studied a cross-sectional sample of 151 randomly selected subjects (79 men, 72 women; mean age 63 years) from the Tasmanian Older Adult Cohort Study. A sagittal T1-weighted fat-suppression MRI scan of the right hip was performed to determine femoral head cartilage volume, cartilage thickness, and size. An anteroposterior radiograph of the pelvis with weight bearing was performed and scored for radiographic evidence of OA in the right hip. Other factors measured were height, weight, leg strength, serum vitamin D levels, and bone mineral density. Hip cartilage volume was significantly associated with female sex, body mass index, and femoral head size, whereas hip cartilage thickness was significantly associated only with the size of the femoral head. Only female sex was significantly associated with the total radiographic OA score and the joint space narrowing (JSN) score, but not the osteophyte score. Radiographic JSN of the hip, especially axial JSN (but not osteophytes), was significantly correlated with hip cartilage volume and thickness. Femoral head cartilage volume and thickness have modest but significant construct validity when correlated with radiographic findings. Furthermore, the generally stronger associations with volume compared with radiographic OA suggest that MRI may be superior at identifying risk factors for hip OA.
    Arthritis & Rheumatism 05/2005; 52(4):1069-76. · 7.87 Impact Factor
  • Article: Knee cartilage defects: association with early radiographic osteoarthritis, decreased cartilage volume, increased joint surface area and type II collagen breakdown.
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    ABSTRACT: To generate hypotheses regarding the associations between knee cartilage defects and knee radiographic osteoarthritis (ROA), cartilage volume, bone size and type II collagen breakdown in adults. A cross-sectional convenience sample of 372 male and female subjects (mean age 45 years, range 26-61) was studied. Knee cartilage defect score (0-4) and prevalence (a defect score of > or =2), cartilage volume, and bone surface area were determined using T1-weighted fat saturation MRI. Urinary levels of C-terminal crosslinking telopeptide of type II collagen (U-CTX-II) were measured by enzyme-linked immunosorbent assay. Height, weight and ROA were measured by standard protocols. In multivariate analysis, the severity and prevalence of knee cartilage defects were significantly and independently associated with tibiofemoral osteophytes (regression coefficient (beta): +0.86 to +1.31/unit, odds ratio (OR): 2.97-3.68/unit, all P<0.05 with the exception of OR in lateral tibiofemoral compartment) and tibial bone area (beta: +0.11 to +0.25/cm2; OR: 1.33-1.58/cm2, all P<0.01). Knee cartilage defects were inconsistently associated with joint space narrowing after adjustment for osteophytes but consistently with knee cartilage volume (beta: -0.27 to -0.70/ml; OR: 0.16-0.56/ml, all P<0.01 except for OR at lateral tibial cartilage site P=0.06). Lastly, knee cartilage defect severity was significantly associated with U-CTX-II (Partial r=+0.18, P<0.001 for total cartilage defect score). Osteophytes and increasing knee bone size may be causally related to knee cartilage defects. Furthermore, knee cartilage defects may result in increased cartilage breakdown leading to decreased cartilage volume and joint space narrowing suggesting an important role for knee cartilage defects in early knee OA.
    Osteoarthritis and Cartilage 04/2005; 13(3):198-205. · 3.90 Impact Factor
  • Article: Knee structural alteration and BMI: a cross-sectional study.
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    ABSTRACT: To describe the associations among BMI, knee cartilage morphology, and bone size in adults. A cross-sectional convenience sample of 372 male and female subjects (mean age, 45 years; range, 26 to 61 years) was studied. Knee articular cartilage defect score (0 to 4) and prevalence (defect score of >/=2), volume, and thickness, as well as bone surface area and/or volume, were determined at the patellar, tibial, and femoral sites using T1-weighted fat-saturation magnetic resonance imaging. Height, weight, BMI, and radiographic osteoarthritis were measured by standard protocols. In multivariate analysis in the whole group, BMI was significantly associated with knee cartilage defect scores (beta: +0.016/kg/m(2) to +0.083/kg/m(2), all p < 0.05) and prevalence (odds ratio: 1.05 to 1.12/kg/m(2), all p < 0.05 except for the lateral tibiofemoral compartment). In addition, BMI was negatively associated with patellar cartilage thickness only (beta = -0.021 mm/kg/m(2); p = 0.039) and was positively associated with tibial bone area (medial: beta = +7.1 mm(2)/kg/m(2), p = 0.001; lateral: beta = +3.2 mm(2)/kg/m(2), p = 0.037). Those who were obese also had higher knee cartilage defect severity and prevalence and larger medial tibial bone area but no significant change in cartilage volume or thickness compared with those of normal weight. This study suggests that knee cartilage defects and tibial bone enlargement are the main structural changes associated with increasing BMI particularly in women. Preventing these changes may prevent knee osteoarthritis in overweight and obese subjects.
    Obesity research 02/2005; 13(2):350-61. · 4.95 Impact Factor