Browsing by Author "Berner, Karina"

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    Biomechanical analysis of specific motor impairments contributing to early functional decline in adults living with HIV-1 infection : a sub-study to the Cape Winelands HAART to HEART (Prevalence)/EndoAfrica study
    (Stellenbosch : Stellenbosch University, 2019-04) Berner, Karina; Louw, Q. A.; Morris, L. D.; Baumeister, J.; Stellenbosch University. Faculty of Medicine and Health Sciences. Dept. of Health & Rehabilitation Sciences. Physiotherapy.
    ENGLISH SUMMARY : Background: HIV-1 infection has become a chronic condition. Although people living with HIV-1 infection (PLHIV) now have near-normal life expectancies, walking-related impairments remain concerning as they occur early and may lead to falls. A poor understanding remains of how movement patterns are affected due to a lack of biomechanical studies. Three-dimensional (3D) motion analysis can provide insight into movement patterns and assist in identifying a valid performance-based screening test for detecting early motor impairments in PLHIV. Aim: The aim of this research was to investigate gait and balance impairments existing in PLHIV using 3D motion analysis. It further aimed to correlate 3D analysis findings (via a gait summary score), as well as self-reported function and history and fear of falling, to physical performance tests which may be considered in clinical practice to screen for early functional decline in PLHIV. Methods: The research was divided into three parts: Part I presented a systematic review describing objective gait and balance impairments in PLHIV. Results contributed to the theoretical groundwork for study conceptualisation and aided in selecting clinically relevant biomechanical outcomes and performance-based tests. Part II comprised validity and reliability testing of a portable 3D gait analysis (3DGA) system, newly obtained by the motion laboratory, in 16 healthy student volunteers, as well as in eight consecutively recruited PLHIV and eight community-matched seronegative participants (SNP). The studies determined the psychometric properties of specific 3DGA outcomes to aid appropriate data interpretation in the next phase. Part III comprised the main observational study to cross-sectionally describe key biomechanical characteristics in 50 PLHIV relative to 50 community-matched SNP (consecutively sampled). The study was conducted in a clinical setting, and performancebased tests were assessed in addition to the 3D motion analysis. Gait analysis results, fallrelated outcomes and self-reported function were correlated to clinical test performance to identify the most valid performance-based screening test. Main results: The systematic review (Part I) revealed some agreement that PLHIV walk slower and have increased centre of pressure (COP) excursions and postural reflex latencies, particularly under challenging conditions. No included studies used 3DGA. The validity and reliability studies (Part II) demonstrated that, with regular recalibration, the 3DGA system reliably measures gait biomechanics in SNP and PLHIV, except for four discrete angles. The system/model highly compares to the reference model after accounting for modelling differences. The field study (Part III) revealed that the gait of PLHIV (median age: 36.61 years) was significantly slowed and rigid relative to SNP (median age: 31.10 years). This pattern manifested when walking at a usual pace or when performing a dual task. Dual task walking further revealed joint range of motion (ROM) changes at the hip and knee in a distal-to-proximal pattern-shift. PLHIV also demonstrated increased COP excursion in dual task single-leg stance. PLHIV were significantly slower in completing the Five-Times Sit-To-Stand (5STS) Test. Slowed sit-tostand was significantly related to gait rigidity, worse self-reported function, and fear of falling. Conclusion: Relatively young PLHIV present with biomechanical gait and balance impairments that resemble patterns noted in elders, especially under dual task conditions. The 5STS test is recommended as a valid clinical screening test. These findings improve understanding of movement impairments in PLHIV and highlight the need for early screening. Further research is needed to determine whether the 5STS test predicts falls, and whether the impairments noted in PLHIV are reversible. Early identification and rehabilitation can reduce healthcare utilisation needs in PLHIV.
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    Fall history and associated factors among adults living with HIV-1 in the Cape Winelands, South Africa : an exploratory investigation
    (Oxford University Press, 2019) Berner, Karina; Strijdom, Hans; Essop, M. Faadiel; Webster, Ingrid; Morris, Linzette; Louw, Quinette
    Background. People with HIV-1 (PWH) exhibit a high fall incidence and increased fracture risk. As little is known about fall frequency and associated factors in PWH residing in lower-middle-income countries (LMIC), we investigated fall frequency, bone quality, and factors associated with fall history in a South African cohort. Methods. Fifty PWH without obvious predisposing factors for mobility impairments attending 2 public primary care clinics in the Western Cape region participated. Demographic, clinical, and physical performance data were collected. Falls were assessed retrospectively over 12 months. Mobility and balance were evaluated using a physical performance battery. Bone mineral density was screened using quantitative ultrasound (QUS). Associations between variables and falls grouping were analyzed using chi-square tests, t tests, and Mann-Whitney U tests, and effect sizes (ES) were calculated. Results. Thirty-four percent of PWH (median age, 36.6 years) reported falling during the past year, and 41.2% of fallers reported multiple falls. Fallers had more mobility problems (P = .013), higher fear of falling (P = .007), higher fracture history (P = .003), worse balance performance (P < .001), higher proportions of detectable viral loads (P = .021), and poorer bone quality (P = .040). Differences were of medium to large ES. Conclusions. This exploratory study is the first to show that relatively young South African PWH without obvious predisposing factors for gait and balance impairments experience falls. The observed fall-associated factors warrant further research using larger samples and longitudinal designs to ascertain fall predictors within this population.
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    Falls in people living with HIV : a scoping review
    (BMJ Open, 2020-11) Charumbira, Maria Yvonne; Berner, Karina; Louw, Quinette Abegail
    Objectives: Recent research has indicated seemingly increased propensity for falls and accelerated bone demineralisation in people living with HIV (PLWH). We aim to map out the extent and nature of existing research relating to falls in PLWH and describe the relationship between bone demineralisation and falls in PLWH. Methods: A scoping review was done following Arksey & O’Malley’s methodological framework and recommendations from Joanna Briggs Institute. Four databases were searched until October 2019 for peer-reviewed studies available in English reporting on the definition, prevalence, assessment, risk factors and interventions for falls in PLWH as well as information on bone demineralisation linked to falls in PLWH. Narrative reviews were excluded. Two reviewers independently performed the extraction using a predesigned Excel sheet. A descriptive analysis of extracted information was done. Results: Fourteen studies on falls in older PLWH were identified, with all but one study conducted in high-income countries. Prevalence of falls in PLWH ranged from 12% to 41%. Variable assessment tools/tests were used to assess potential risk factors, but it remains to be determined which are more predictive and appropriate for use among PLWH. Considerable agreement existed for risk factors regarding use of medications while evidence regarding functional and cognitive impairments were variable. Few studies compared risk factors for falls in PLWH with those in age-matched and sex-matched seronegative population. There is currently no evidence for interventions to prevent or reduce falls risk in PLWH. Conclusion More research is needed on falls in younger cohorts of PLWH and in sub-Saharan Africa where HIV is most prevalent and more robust clades exist. More studies need to report on data in seronegative controls to determine risk factors unique to PLWH. More intervention studies targeted at falls prevention and promotion of bone health are required. Quality clinical practice guidelines highlighting validated assessment tools and outcome measures need to be developed.
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    Kinematics and temporospatial parameters during gait from inertial motion capture in adults with and without HIV : a validity and reliability study
    (BMC (part of Springer Nature), 2020-07-24) Berner, Karina; Cockcroft, John; Louw, Quinette
    Background: Inertial measurement unit (IMU)-based motion capture systems are gaining popularity for gait analysis outside laboratories. It is important to determine the performance of such systems in specific patient populations. We aimed to validate and determine within-day reliability of an IMU system for measuring lower limb gait kinematics and temporal–spatial parameters (TSP) in people with and without HIV. Methods: Gait was recorded in eight adults with HIV (PLHIV) and eight HIV-seronegative participants (SNP), using IMUs and optical motion capture (OMC) simultaneously. Participants performed six gait trials. Fifteen TSP and 28 kinematic angles were extracted. Intraclass correlations (ICC), root-mean-square error (RMSE), mean absolute percentage error and Bland–Altman analyses were used to assess concurrent validity of the IMU system (relative to OMC) separately in PLHIV and SNP. IMU reliability was assessed during within-session retest of trials. ICCs were used to assess relative reliability. Standard error of measurement (SEM) and percentage SEM were used to assess absolute reliability. Results: Between-system TSP differences demonstrated acceptable-to-excellent ICCs (0.71–0.99), except for double support time and temporophasic parameters (< 0.60). All TSP demonstrated good mean absolute percentage errors (≤7.40%). For kinematics, ICCs were acceptable to excellent (0.75–1.00) for all but three range of motion (ROM) and four discrete angles. RMSE and bias were 0.0°–4.7° for all but two ROM and 10 discrete angles. In both groups, TSP reliability was acceptable to excellent for relative (ICC 0.75–0.99) (except for one temporal and two temporophasic parameters) and absolute (%SEM 1.58–15.23) values. Reliability trends of IMU-measured kinematics were similar between groups and demonstrated acceptable-to-excellent relative reliability (ICC 0.76–0.99) and clinically acceptable absolute reliability (SEM 0.7°–4.4°) for all but two and three discrete angles, respectively. Both systems demonstrated similar magnitude and directional trends for differences when comparing the gait of PLHIV with that of SNP. Conclusions: IMU-based gait analysis is valid and reliable when applied in PLHIV; demonstrating a sufficiently low precision error to be used for clinical interpretation (< 5° for most kinematics; < 20% for TSP). IMU-based gait analysis is sensitive to subtle gait deviations that may occur in PLHIV.
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    Objective impairments of gait and balance in adults living with HIV-1 infection : a systematic review and meta-analysis of observational studies
    (BioMed Central, 2017-08-01) Berner, Karina; Morris, Linzette; Baumeister, Jochen; Louw, Quinette
    Background: Gait and balance deficits are reported in adults with HIV infection and are associated with reduced quality of life. Current research suggests an increased fall-incidence in this population, with fall rates among middle-aged adults with HIV approximating that in seronegative elderly populations. Gait and postural balance rely on a complex interaction of the motor system, sensory control, and cognitive function. However, due to disease progression and complications related to ongoing inflammation, these systems may be compromised in people with HIV. Consequently, locomotor impairments may result that can contribute to higher-than-expected fall rates. The aim of this review was to synthesize the evidence regarding objective gait and balance impairments in adults with HIV, and to emphasize those which could contribute to increased fall risk. Methods: This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. An electronic search of published observational studies was conducted in March 2016. Methodological quality was assessed using the NIH Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. Narrative synthesis of gait and balance outcomes was performed, and meta-analyses where possible. Results: Seventeen studies were included, with fair to low methodological quality. All studies used clinical tests for gait-assessment. Gait outcomes assessed were speed, initiation-time and cadence. No studies assessed kinetics or kinematics. Balance was assessed using both instrumented and clinical tests. Outcomes were mainly related to center of pressure, postural reflex latencies, and timed clinical tests. There is some agreement that adults with HIV walk slower and have increased center of pressure excursions and -long loop postural reflex latencies, particularly under challenging conditions. Conclusions: Gait and balance impairments exist in people with HIV, resembling fall-associated parameters in the elderly. Impairments are more pronounced during challenging conditions, might be associated with disease severity, are not influenced by antiretroviral therapy, and might not be associated with peripheral neuropathy. Results should be interpreted cautiously due to overall poor methodological quality and heterogeneity. Locomotor impairments in adults with HIV are currently insufficiently quantified. Future research involving more methodological uniformity is warranted to better understand such impairments and to inform clinical decision-making, including fall-prevention strategies, in this population.
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    Physiotherapists’ awareness of risk of bone demineralisation and falls in people living with HIV : a qualitative study
    (BMC (part of Springer Nature), 2021-04-13) Charumbira, Maria Y.; Berner, Karina; Louw, Quinette
    Background: Recent research has indicated a seemingly increased propensity for both falls and accelerated bone loss in people living with HIV (PLWH). Physiotherapists play a crucial role in optimising function and quality of life of PLWH through prevention of falls and reducing the harm that results. Aim: This study aimed to explore physiotherapists’ awareness of falls risk and accelerated bone demineralisation in PLWH and their perceptions of current falls prevention strategies in the care of PLWH in selected regions of sub- Saharan Africa. Method: An exploratory descriptive qualitative research method was employed to explore physiotherapists’ perceptions and experiences regarding bone health and falls in PLWH. In-depth semi-structured telephonic interviews were used to collect data from 21 physiotherapists working in primary HIV care. Transcribed interview data were coded in Atlas.ti.8® and analysed using inductive thematic analysis. Results: The primary study revealed a lack of awareness by physiotherapists of falls risk and bone demineralisation in PLWH. As such, physiotherapists did not link falls or fractures to HIV or antiretroviral therapy (ART) when they did observe such events during their general patient assessments. However, in retrospect, some physiotherapists were able to recognise risk factors linked to falls in those with HIV. Current services for falls prevention, as perceived by the physiotherapists, were sub-optimal. Conclusion: Physiotherapists may need to be more aware of the potential risk of falls and bone demineralisation in PLWH and routinely assess for these phenomena in both older and younger PLWH.