ORCID Profile
0000-0002-5530-981X
Current Organisations
University of Sydney
,
Liverpool Hospital
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
Publisher: Elsevier BV
Date: 02-2011
DOI: 10.1016/J.JELEKIN.2010.08.007
Abstract: Limited information is available to support the validity of using surface electrodes to record activity from infraspinatus. The aims of this study were to compare infraspinatus activity recorded using surface and intramuscular electrodes during several shoulder isometric and dynamic tasks and to establish if infraspinatus activity recorded using intramuscular electrodes is representative of whole muscle activity. Surface and intramuscular electrodes were placed over infraspinatus in nine subjects without shoulder pain. Isometric shoulder external rotation, at 0° and 90° abduction, and extension were performed at six loads. Dynamic shoulder flexion and abduction were performed at 70% maximum load. Results indicated that while surface and intramuscular electrodes record similar activation patterns when infraspinatus is moderately to highly activated (r and slope ∼ 1), only intramuscular electrodes accurately reflected low (<10%MVC) infraspinatus activity (r=0.95 ± 0.04, slope=15.6 ± 16.3). The linear relationship between the activity recorded with surface and intramuscular electrodes when infraspinatus is moderately to highly active also indicated that intramuscular recordings from infraspinatus are representative of activity in the whole muscle. To ensure validity in reporting infraspinatus activation patterns when studying functional shoulder tasks in which infraspinatus may be relatively active and inactive at different phases of these tasks, intramuscular electrodes should be used to record infraspinatus activity.
Publisher: SAGE Publications
Date: 21-07-2016
Abstract: The development of radiographic knee osteoarthritis (OA) after an anterior cruciate ligament (ACL) rupture has long been studied and proven in the adolescent population. However, similar exhaustive investigations have not been conducted in mature-aged athletes or in older populations. To identify whether an older adult population had an increased risk of incident radiographic knee OA after a traumatic knee injury compared with a young adult population. Cohort study Level of evidence, 3. Patients with ACL ruptures who underwent primary reconstruction were enrolled in a prospective, longitudinal single-center study over 15 years. The adult cohort was defined as participants aged ≥35 years who had a knee injury resulting in an ACL tear, the adolescent-young cohort suffered similar knee injuries and were aged ≤25 years, and a third cohort of participants aged 26 to 34 years who suffered a knee injury was included to identify the existence of any age-related dose-response relationship for the onset of radiographic knee OA. A Kaplan-Meier survival analysis was employed to determine the occurrence of incident radiographic OA across the study populations at 2, 5, 10, and 15 years after reconstruction. Significance at each time point was analyzed using chi-square tests. A total of 215 patients, including 112 adolescents (mean age, 20.4 years 50.9% female), 71 patients aged 26 to 34 years (mean age, 29.2 years 42.3% female), and 32 adults (mean age, 40.2 years 59.4% female), were assessed for International Knee Documentation Committee (IKDC) grading on knee radiographs. It was found that 53.0% and 77.8% of adults at a respective 10 and 15 years after reconstruction had an IKDC grade of B or greater compared with 17.7% and 61.6% of the adolescent-young cohort. Chi-square testing found that adults developed OA earlier than adolescents at 5 and 10 years after reconstruction ( P = .017 and P .0001, respectively). However, survival analysis did not demonstrate that adults were more likely to develop radiographic knee OA at 15 years after reconstruction compared with the adolescent-young cohort ( P = .4). The age at which an ACL injury is sustained does not appear to influence the rate of incident radiographic knee OA, although mature-aged athletes are likely to arrive at the OA endpoint sooner.
Publisher: Elsevier BV
Date: 04-2018
Publisher: Wiley
Date: 05-2021
DOI: 10.1002/ACR2.11249
Publisher: Elsevier BV
Date: 04-2017
Publisher: Elsevier BV
Date: 04-2017
Publisher: Wiley
Date: 30-12-2016
Publisher: Elsevier BV
Date: 04-2016
Publisher: Georg Thieme Verlag KG
Date: 04-12-2012
Abstract: Osteoarthritis (OA) is the most common joint disorder and a leading cause of disability. Due to an aging population and increasing obesity, the incidence of OA is rising. The etiology of OA is multifactorial and complex thus prevention of OA remains challenging. Risk factors can be ided into person-level factors such as age, sex, obesity, genetics, race/ethnicity, and diet, and joint-level factors including injury, malalignment, and abnormal loading of the joints. This review provides a brief overview of the person-level risk factors and a more in-depth analysis of those at the joint level. It is only through an improved understanding of risk factors for the disease that we may be able to intervene meaningfully and prevent its occurrence.
Publisher: Elsevier BV
Date: 02-2014
DOI: 10.1016/J.BERH.2014.01.004
Abstract: Osteoarthritis (OA) is a leading cause of disability and its incidence is rising due to increasing obesity and an ageing population. Risk factors can be ided into person-level factors, such as age, sex, obesity, genetics, race/ethnicity and diet, and joint-level factors including injury, malalignment and abnormal loading of the joints. The interaction of these risk factors is complex and provides a challenge to the managing physician. The purpose of this review is to illustrate how each of these factors interact together to instigate incident OA as well as to outline the need for ongoing epidemiologic studies for the future prevention of both incident and progressive OA. It is only by understanding the impact of this disease and the modifiable risk factors that we will be able to truly target public health prevention interventions appropriately.
Publisher: Wiley
Date: 26-03-2021
DOI: 10.1002/ACR.24148
Abstract: To test the effectiveness of a 32-week, stepped-care intervention on disease remission rates in overweight and obese patients with medial tibiofemoral osteoarthritis (OA) compared to controls. In this randomized controlled trial, eligible participants were ≥50 years of age with a body mass index of ≥28 kg/m Disease remission at 32 weeks was achieved by 18 of 68 (26%) in the control group and 32 of 82 (39%) in the stepped-care group (difference 12.6% [95% confidence interval -2.3, 27.4], P = 0.10). The stepped-care group showed an improvement in pain and function between baseline and 20 weeks. While functional improvement was maintained at 32 weeks, pain levels tended to get worse between weeks 20 and 32. The proposed intervention did not promote a significant difference in the rate of disease remission in comparison to the control group for overweight or obese patients with medial tibiofemoral OA.
Publisher: BMJ
Date: 12-2017
DOI: 10.1136/BMJOPEN-2017-018495
Abstract: Current guidelines recommend tailored interventions to optimise knee osteoarthritis (OA) management. However, models of care still have a ‘one size fits all’ approach, which is suboptimal as it ignores patient heterogeneity. This study aims to compare a stepped care strategy with standard care for overweight and obese persons with medial tibiofemoral OA. Participants will be randomised into two groups (85 each). The intervention will receive a diet and exercise programme for 18 weeks in the first step of the study. Disease remission will then be assessed using the Patient Acceptable Symptom State (PASS). PASS is defined as the highest level of symptom beyond which patients consider themselves well and takes into account pain intensity, patient’s global assessment of disease activity and degree of functional impairment. In the second step, participants in remission will continue with diet and exercise. If remission is not achieved, participants will be assigned in a hierarchical order to cognitive behavioural therapy, knee brace or muscle strengthening for 12 weeks. The intervention will be decided based on their clinical presentation for symptoms of depression and varus malalignment. Participants without depression or varus malalignment will undertake a muscle strengthening programme. The control group will receive educational material related to OA management. Main inclusion criteria are age ≥50 years, radiographic medial tibiofemoral OA, body mass index (BMI) ≥28 kg/m 2 , knee pain ≥40 (Visual Analogue Scale, 0–100), PASS (0–100) for pain and global assessment, and 31 for functional impairment. Outcomes will be measured at 20-week and 32-week visits. The primary outcome is disease remission at 32 weeks. Other outcomes include functional mobility patient-reported outcomes BMI waist-hip ratio quadriceps strength symptoms of depression, anxiety and stress and knee range of motion. The analysis will be performed according to the intention-to-treat principle. The local ethics committee approved this protocol (HREC/14/HAWKE/381). Dissemination will occur through presentations at international conferences and publication in peer-reviewed journals. ACTRN12615000227594.
Publisher: Wiley
Date: 26-02-2020
No related grants have been discovered for Victoria Johnson.