Concurrent validity and within-session reliability of gait kinematics measured using an inertial motion capture system with repeated calibration

IntroductionWearable inertial measurement units (IMUs) enable gait analysis in the clinic, but require calibrations that may affect subsequent gait measurements. This study assessed concurrent validity and within-session reliability of gait kinematics measured by a frequently calibrated IMU-based system. Calibration pose accuracy and intra-rater repeatability, and IMU orientation tracking accuracy, were additionally quantified. MethodsCalibration poses and gait were recorded in 15 women using IMUs and optical motion capture (OMC) (reference standard) simultaneously. Participants performed six consecutive trials: each comprising a calibration pose and a walk. IMU tracking was assessed separately (once-off) using technical static and dynamic tests. Differences of > 5° constituted clinical significance. ResultsConcurrent validity for gait revealed clinically significant between-system differences for sagittal angles (root-mean-square error [RMSE] 6.7°–15.0°; bias −9.3°–3.0°) and hip rotation (RMSE 7.9°; bias −4.2°). After removing modelling offsets, differences for all angles (except hip rotation) were  0.8), except hip rotation, pelvic tilt and -obliquity. Within-session reliability of IMU-measured gait angles was clinically acceptable (standard error of measurement [SEM] < 5°). Calibration poses were repeatable (SEM 0.3°–2.2°). Pose accuracy revealed mean absolute differences (MAD) < 5° for all angles except sagittal ankle, hip and pelvis. IMU tracking accuracy demonstrated RMSE ≤ 2.0°. ConclusionA frequently calibrated IMU system provides reliable gait measurements; comparing highly to OMC after removing modelling differences. Calibration poses can be implemented accurately for most angles and consistently. IMU-measured gait data are clinically useful and comparable within participants, but should not be compared to OMC-measured data

Cross-cultural adaptation: South African Gestational Diabetes Mellitus Knowledge Questionnaire

Background: Many serious adverse events associated with gestational diabetes mellitus (GDM) can be mitigated by timely glucose control during pregnancy, achieved through education and lifestyle choices. The aim of this study was to translate and cross-culturally adapt and test the preliminary internal consistency and test-retest reliability of the South African English, Afrikaans and isiXhosa versions of the GDM Knowledge Questionnaire (GDMKQ). Methods: A prospective, observational study was conducted at a high-risk antenatal clinic in South Africa. Pregnant women ≥ 18 years with GDM were consecutively sampled. Semantic equivalence between the original and adapted versions was assessed. Face and content validity, internal consistency and test–retest reliability were evaluated. Results: The three SA-GDMKQ versions demonstrated good face and content validity. For internal consistency, Cronbach’s alpha values were 0.534 for the Afrikaans version, 0.434 for the English version and 0.621 for the isiXhosa version. Test–retest reliability found kappa (standard error [s.e.]) values ranged between −0.03 (0.18) and 0.89 (0.13) for the English version, between −0.07 (0.18) and 0.53 (0.13) for the Afrikaans version and between 0.28 (0.18) and 0.87 (0.17) for the isiXhosa version. All versions of the SA-GDMKQ had a statistically significant (p  0.001) positive linear correlation between the total scores. Conclusion: The English, Afrikaans and isiXhosa SA-GDMKQ versions were found to be feasible and easy to comprehend, although lower internal consistency and test–retest reliability were displayed. Further validation of the psychometric properties of the English, Afrikaans and isiXhosa versions of the SA-GDMKQ among larger sample groups is however warranted. Contribution: This study adds to the knowledge around developing and using culturally appropriate questionnaires and outcome measures in research and clinical practice

Understanding the value of rehabilitation: Perspectives from South African Stakeholders

Background: The need for rehabilitation in South Africa has doubled between 1990 and 2017 and is expected to increase in the coming years. However, the rehabilitation needs of South Africans (and globally) remain largely unmet. Establishing a common understanding of the value of rehabilitation can inform clinical practice and policymaking to achieve Universal Health Coverage (UHC). Objectives: This study aims to explore the value of rehabilitation services in South Africa’s public healthcare sector by gathering perspectives from stakeholders. The goal is to inform policy decisions related to the implementation of National Health Insurance (NHI) in South Africa. Method: The study used a phenomenological approach and interpretivist paradigm. Semi-structured interviews were conducted face-to-face, online, or telephonically with 12 stakeholders from various rehabilitation sectors. The value of rehabilitation was analysed and categorised into five main categories: context, service delivery, patient outcomes, economic and financial components, and collaboration within and between sectors. Results: The value of rehabilitation was found to be multifaceted, because of the varying health, economic, and social challenges faced by many South Africans. Conclusion: The study identified components of value-based rehabilitation that should be prioritised in the proposed NHI of South Africa. Future research should explore all stakeholder perspectives, including patients, and provide empirical evidence of rehabilitation’s economic and societal value. Contribution: We highlight priority areas that are central to the value of rehabilitation in South Africa and other low- and middle-income countries (LMICs). Tailoring rehabilitation services to patient and community needs is crucial for achieving value-based care. Given South Africa’s commitment to the United Nations Convention on the Rights of Persons with Disabilities, prioritising rehabilitation remains essential

Virtual reality exposure therapy as treatment for pain catastrophizing in fibromyalgia patients: proof-of-concept study (Study Protocol)

<p>Abstract</p> <p>Background</p> <p>Albeit exercise is currently advocated as one of the most effective management strategies for fibromyalgia syndrome (FMS); the implementation of exercise as a FMS treatment in reality is significantly hampered by patients' poor compliance. The inference that pain catastrophizing is a key predictor of poor compliance in FMS patients, justifies considering the alteration of pain catastrophizing in improving compliance towards exercises in FMS patients. The aim of this study is to provide proof-of-concept for the development and testing of a novel virtual reality exposure therapy (VRET) program as treatment for exercise-related pain catastrophizing in FMS patients.</p> <p>Methods</p> <p>Two interlinked experimental studies will be conducted. Study 1 aims to objectively ascertain if neurophysiological changes occur in the functional brain areas associated with pain catastrophizing, when catastrophizing FMS subjects are exposed to visuals of exercise activities. Study 2 aims to ascertain the preliminary efficacy and feasibility of exposure to visuals of exercise activities as a treatment for exercise-related pain catastrophizing in FMS subjects. Twenty subjects will be selected from a group of FMS patients attending the Tygerberg Hospital in Cape Town, South Africa and randomly allocated to either the <b>VRET </b>(intervention) group or <b>waiting list </b>(control) group. Baseline neurophysiological activity for subjects will be collected in study 1 using functional magnetic resonance imaging (fMRI). In study 2, clinical improvement in pain catastrophizing will be measured using fMRI (objective) and the pain catastrophizing scale (subjective).</p> <p>Discussion</p> <p>The premise is if exposing FMS patients to visuals of various exercise activities trigger the functional brain areas associated with pain catastrophizing; then as a treatment, repeated exposure to visuals of the exercise activities using a VRET program could possibly decrease exercise-related pain catastrophizing in FMS patients. Proof-of-concept will either be established or negated. The results of this project are envisaged to revolutionize FMS and pain catastrophizing research and in the future, assist health professionals and FMS patients in reducing despondency regarding FMS management.</p> <p>Trial registration</p> <p>PACTR201011000264179</p

The prevalence of low back pain in Africa : a systematic review

Background: Low back pain (LBP) is the most prevalent musculoskeletal condition and one of the most common causes of disability in the developed nations. Anecdotally, there is a general assumption that LBP prevalence in Africa is comparatively lower than in developed countries. The aim of this review was to systematically appraise the published prevalence studies conducted on the African continent to establish the prevalence of LBP in Africa. Methods: A comprehensive search was conducted in April 2006. The following databases PEDro, Psychinfo, Science Direct, SportsDiscus, PubMed, CINAHL, Biblioline Pro-African Wide NiPAD and SA ePublications were individually searched using specifically developed search strategies for epidemiological research conducted on LBP amongst the African population. Two reviewers independently evaluated the methodological quality of the studies reviewed. Results: A total of 27 eligible epidemiological studies were included in this review. The majority of the studies (63%) were conducted in South Africa (37%) and Nigeria (26%). The most common population group involved workers (48%), while scholars comprised 15% of the population. 67% of the studies were found to be methodologically sound, and the LBP prevalence of these were analyzed. The mean LBP point prevalence among the adolescents was 12% and among adults was 32%. The average one year prevalence of LBP among adolescents was 33% and among adults was 50%. The average lifetime prevalence of LBP among the adolescents was 36% and among adults was 62%. Conclusion: The findings support the global burden of disease of LBP, in addition to suggesting that LBP prevalence among Africans is rising and is of concern. Further research into the most effective strategies to prevent and manage LBP in Africa is warranted.Peer Reviewe