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Nishiyama K.K.,University of Calgary | Nishiyama K.K.,McCaig Institute for Bone and Joint Health | Macdonald H.M.,University of British Columbia | Macdonald H.M.,Child and Family Research Institute | And 5 more authors.
Osteoporosis International | Year: 2013

High-resolution peripheral quantitative computed tomography (HR-pQCT) measurements of distal radius and tibia bone microarchitecture and finite element (FE) estimates of bone strength performed well at classifying postmenopausal women with and without previous fracture. The HR-pQCT measurements outperformed dual energy x-ray absorptiometry (DXA) at classifying forearm fractures and fractures at other skeletal sites. Introduction: Areal bone mineral density (aBMD) is the primary measurement used to assess osteoporosis and fracture risk; however, it does not take into account bone microarchitecture, which also contributes to bone strength. Thus, our objective was to determine if bone microarchitecture measured with HR-pQCT and FE estimates of bone strength could classify women with and without low-trauma fractures. Methods: We used HR-pQCT to assess bone microarchitecture at the distal radius and tibia in 44 postmenopausal women with a history of low-trauma fracture and 88 age-matched controls from the Calgary cohort of the Canadian Multicentre Osteoporosis Study (CaMos) study. We estimated bone strength using FE analysis and simulated distal radius aBMD from the HR-pQCT scans. Femoral neck (FN) and lumbar spine (LS) aBMD were measured with DXA. We used support vector machines (SVM) and a tenfold cross-validation to classify the fracture cases and controls and to determine accuracy. Results: The combination of HR-pQCT measures of microarchitecture and FE estimates of bone strength had the highest area under the receiver operating characteristic (ROC) curve of 0.82 when classifying forearm fractures compared to an area under the curve (AUC) of 0.71 from DXA-derived aBMD of the forearm and 0.63 from FN and spine DXA. For all fracture types, FE estimates of bone strength at the forearm alone resulted in an AUC of 0.69. Conclusion: Models based on HR-pQCT measurements of bone microarchitecture and estimates of bone strength performed better than DXA-derived aBMD at classifying women with and without prior fracture. In future, these models may improve prediction of individuals at risk of low-trauma fracture. © 2012 International Osteoporosis Foundation and National Osteoporosis Foundation.

Dunne T.J.,Regional Fall and Injury Prevention Program | Gaboury I.,Universite de Sherbrooke | Ashe M.C.,Center for Hip Health and Mobility | Ashe M.C.,University of British Columbia
Journal of Evaluation in Clinical Practice | Year: 2014

Rationale, aims and objectives Acute inpatient falls are common and serious adverse events that lead to injury, prolonged hospitalization and increased cost of care. To determine the difference in total acute hospital care length of stay (LOS) for patients with and without an in-hospital fall (IHF), regardless of degree of harm. Methods This was a retrospective observational study at a 728-bed acute care teaching hospital. We used propensity scores to match 292 patients with 330 controls by case mix group, sex, Resource Intensity Weights and week of admission. We used two administrative databases: hospital fall incident reporting system and Discharge Abstract Database. We reviewed all IHF incidents for patients 18 years and older, admitted to inpatient acute care hospital units/programs between 1 November 2009 and 31 August 2011. Results The average LOS for IHF cases was 37.2 days [median 26.5 days; interquartile range (IQR) 14, 54] and 25.7 days (median 13 days; IQR 5, 33) for matched control patients. Survival analysis results indicated that patients who did not have an IHF were 2.4 times (95% CI 2.1, 2.7; P < 0.001) more likely to be discharged earlier from acute care than patients who had an IHF. Conclusions Experiencing either an injurious or a non-injurious fall during an acute care hospitalization was associated with prolonged LOS. © 2014 John Wiley & Sons, Ltd.

Almeida O.P.,University of Western Australia | Khan K.M.,University of British Columbia | Khan K.M.,Center for Hip Health and Mobility | Hankey G.J.,University of Western Australia | And 3 more authors.
British Journal of Sports Medicine | Year: 2014

Background: Physical activity has been associated with improved survival, but it is unclear whether this increase in longevity is accompanied by preserved mental and physical functioning, also known as healthy ageing. We designed this study to determine whether physical activity is associated with healthy ageing in later life. Methods: We recruited a community-representative sample of 12 201 men aged 65-83 years and followed them for 10-13 years. We assessed physical activity at the beginning and the end of the follow-up period. Participants who reported 150 min or more of vigorous physical activity per week were considered physically active. We monitored survival during the follow-up period and, at study exit, assessed the mood, cognition and functional status of survivors. Healthy ageing was defined as being alive at the end of follow-up and having a Patient Health Questionnaire score <10, Telephone Interview for Cognitive Status score >27, and no major difficulty in any instrumental or basic activity of daily living. Cox regression and general linear models were used to estimate HR of death and risk ratio (RR) of healthy ageing. Analyses were adjusted for age, education, marital status, smoking, body mass index and history of hypertension, diabetes, coronary heart disease and stroke. Results: Two thousand and fifty-eight (16.9%) participants were physically active at study entry. Active men had lower HR of death over 10-13 years than physically inactive men (HR=0.74, 95% CI=0.68 to 0.81). Among survivors, completion of the follow-up assessment was higher in the physically active than inactive group (risk ratio, RR=1.18, 95% CI=1.08 to 1.30). Physically active men had greater chance of fulfilling criteria for healthy ageing than inactive men (RR=1.35, 95% CI=1.19 to 1.53). Men who were physically active at the baseline and follow-up assessments had the highest chance of healthy ageing compared with inactive men (RR=1.59, 95% CI=1.36 to 1.86). Conclusions: Sustained physical activity is associated with improved survival and healthy ageing in older men. Vigorous physical activity seems to promote healthy ageing and should be encouraged when safe and feasible.

Varghese R.A.,University of British Columbia | Chang J.,British Columbia Childrens Hospital | Miyanji F.,University of British Columbia | Reilly C.W.,University of British Columbia | And 2 more authors.
Journal of Pediatric Orthopaedics | Year: 2011

PURPOSE: The purpose of this study was to determine publication rates of all abstracts submitted for presentation at the annual conference of the Pediatric Orthopaedic Society of North America (POSNA) comparing papers accepted for presentation with those that were not accepted and to determine the median times to publication and the mean impact factor of journals that published papers from the 2 groups. METHODS: The titles and authors of all abstracts submitted for presentation to the POSNA for the years 2003 to 2005 were identified. To determine publication status, we conducted a computerized Pubmed search using the first author's name. If multiple publications were identified, the Boolean search operator AND was used to combine author names with key words. The title of each located published article was compared with the title of the abstract. If differences were noted, the abstract content was compared with the final publication. The journals, impact factor was determined using the journal citation report. The median time from conference presentation to publication was determined using a Kaplan-Meier survival analysis. RESULTS: Of 1191 abstracts submitted to the annual meetings of POSNA from the years 2003 through 2005, 440 (37%) were accepted for presentation. Acceptance of submitted abstracts increased from 30% in 2003 to 40% in 2005. Of the 1191 abstracts 599 (50%) were subsequently published by August 2009. The mean publication rate for abstracts accepted for presentation was 58.9% (259 of 440) compared with 45% (339 of 751) for rejected abstracts. The median time to publication of accepted abstracts was not significantly different when compared with that of rejected abstracts. The mean journal impact factor for accepted articles was 2.2 compared with 1.5 for rejected abstracts. CONCLUSIONS: The publication rates of abstracts submitted to POSNA is high compared with those of other international orthopaedic associations. The mean publication rate for accepted abstracts and rejected abstracts has increased substantially from 45% and 38% in 1991 to 1994 to 58.9% and 45% in 2003 to 2005, respectively. The journal in which most of the abstracts are ultimately published is the Journal of Pediatric Orthopaedics Mobility. SIGNIFICANCE: A significant proportion of abstracts not accepted for presentation at POSNA meetings are published in peer-reviewed journals. Nonacceptance of a study for presentation should not be a hindering factor for researchers in attempting to publish their study in peer-reviewed journals. LEVEL OF EVIDENCE: Not applicable. © 2011 Lippincott Williams & Wilkins, Inc.

Culvenor A.G.,University of Queensland | Collins N.J.,University of Melbourne | Guermazi A.,Boston University | Cook J.L.,Monash University | And 7 more authors.
Arthritis and Rheumatology | Year: 2015

Objective To determine the prevalence and factors associated with knee osteoarthritis (OA) defined by magnetic resonance imaging (MRI) and specific OA features on MRI 1 year after anterior cruciate ligament reconstruction (ACLR). Methods Isotropic 3.0T MRI scans were obtained for 111 participants (71 men; mean ± SD age 30 ± 8 years) 1 year after ACLR as well as for 20 age-, sex-, and activity level-matched uninjured controls. The MRI OA Knee Score was used to score specific OA features. MRI-defined tibiofemoral and patellofemoral OA was evaluated based on published criteria. Logistic regression identified factors associated with MRI-defined OA and specific OA features after ACLR. Results Following ACLR, medial and lateral tibiofemoral OA on MRI was observed in 7 participants (6%) and 12 participants (11%), respectively, while 19 participants (17%) had patellofemoral OA on MRI. The femoral trochlea was the region most affected by bone marrow lesions (19% of participants), cartilage lesions (31% of participants), and osteophytes (37% of participants). Meniscectomy at the time of ACLR (odds ratio 6.8 [95% confidence interval 2.0-23.3]) and body mass index (BMI) >25 kg/m2 (odds ratio 3.0 [95% confidence interval 1.3-6.9]) predicted MRI-defined tibiofemoral OA and osteophytes, respectively. Men had higher odds of patellofemoral osteophytes (odds ratio 6.3 [95% confidence interval 2.4-16.2]). No uninjured controls had tibiofemoral or patellofemoral OA on MRI, and specific OA features were uncommon. Conclusion OA 1 year following ACLR was more common than previously recognized, while being absent in uninjured control knees. The patellofemoral compartment seems to be at particular risk for early OA after ACLR, especially in men. The association with meniscectomy and BMI demonstrates the construct validity of MRI criteria. Copyright © 2015 by the American College of Rheumatology.

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