Dara Meldrum

Virtual reality rehabilitation of balance: assessment of the usability of the Nintendo Wii® Fit Plus

Purpose: The aim of this study was to investigate the usability of the Nintendo Wii Fit Plus® (NWFP) in the treatment of balance impairment in vestibular and other neurological disease. Methods: This was a cross-sectional, quasi-experimental study. Participants (n = 26; mean age 43 ± 14, M13:F13) with quantified balance impairment took part in a 30-minute session on the NWFP using exercises and games that challenge balance. Outcomes included the System Usability Scale (SUS), a numerical rating scale of enjoyment and a post treatment questionnaire. Results: The mean SUS score was high (mean 82 ± 18%) with only two participants rating below 50%. There was a negative correlation of age with SUS scores (r = −0.54; p = 0.004). Mean numerical rating scale score (/10) for enjoyment of the NWFP session was 8.4 ± 3. Of the participants, 88.5% said that they would like to use the NWFP in future treatment. Seventy-three percent reported more enjoyment and motivation than usual physiotherapy. No falls occurred during testing. Conclusions: This study has quantified the usability of the NWFP as a treatment for balance impairment showing high levels of usability and enjoyment with no serious adverse effects. The results of this study may assist physiotherapists in devising novel balance rehabilitation programmes. Implications for Rehabilitation The Nintendo Wii Fit Plus® virtual reality system has the potential to improve balance rehabilitation, but usability of this system requires investigation. In this study, patients with balance impairment as a result of neurological disease reported very high levels of usability and enjoyment when performing selected Nintendo Wii Fit Plus® balance exercises and games. The majority of patients preferred the Nintendo Wii Fit Plus to conventional treatment which may have implications for patient compliance with exercise.

Effectiveness of conventional versus virtual reality based vestibular rehabilitation in the treatment of dizziness, gait and balance impairment in adults with unilateral peripheral vestibular loss: a randomised controlled trial

BackgroundUnilateral peripheral vestibular loss results in gait and balance impairment, dizziness and oscillopsia. Vestibular rehabilitation benefits patients but optimal treatment remains unkown. Virtual reality is an emerging tool in rehabilitation and provides opportunities to improve both outcomes and patient satisfaction with treatment. The Nintendo Wii Fit Plus® (NWFP) is a low cost virtual reality system that challenges balance and provides visual and auditory feedback. It may augment the motor learning that is required to improve balance and gait, but no trials to date have investigated efficacy.Methods/DesignIn a single (assessor) blind, two centre randomised controlled superiority trial, 80 patients with unilateral peripheral vestibular loss will be randomised to either conventional or virtual reality based (NWFP) vestibular rehabilitation for 6 weeks. The primary outcome measure is gait speed (measured with three dimensional gait analysis). Secondary outcomes include computerised posturography, dynamic visual acuity, and validated questionnaires on dizziness, confidence and anxiety/depression. Outcome will be assessed post treatment (8 weeks) and at 6 months.DiscussionAdvances in the gaming industry have allowed mass production of highly sophisticated low cost virtual reality systems that incorporate technology previously not accessible to most therapists and patients. Importantly, they are not confined to rehabilitation departments, can be used at home and provide an accurate record of adherence to exercise. The benefits of providing augmented feedback, increasing intensity of exercise and accurately measuring adherence may improve conventional vestibular rehabilitation but efficacy must first be demonstrated.Trial registrationClinical trials.gov identifier: NCT01442623

Maximum voluntary isometric contraction: Reference values and clinical application

Maximum voluntary isometric contraction (MVIC) is a standardized method for measurement of muscle strength in patients with neuromuscular disease. Values obtained from MVIC testing are difficult to interpret at present as normative data are limited. The objective of this study was to generate reference values for MVIC. A convenience sample of 494 healthy men and women aged 20–76 years was recruited. MVIC testing was performed on nine muscle groups bilaterally: neck flexors, shoulder abductors, shoulder adductors, elbow and knee flexors and extensors, and hip and ankle flexors. MVIC was performed using the Quantitative Muscle Assessment system. Age and sex related reference values were calculated for each muscle group using quantile regression. A clinical reporting system was developed to facilitate interpretation of patient values with reference to normal percentiles. Reference values generated from this study can be used to determine the presence and extent of muscle weakness in a given population and to evaluate the effectiveness of treatment interventions.

Test-retest reliability of three dimensional gait analysis: Including a novel approach to visualising agreement of gait cycle waveforms with Bland and Altman plots

BACKGROUND/AIM Estimating the measurement error (reliability) of three dimensional gait analysis (3DGA) is crucial to interpretation of gait data. The purpose of this study was to investigate the intra-rater reliability of 3DGA and apply a novel method of visualising reliability of gait cycle waveforms. METHODS A test re-test design was employed. A convenience sample of 30 healthy adults (18F; 12 M: mean age 30 ± 6.8 years) participated. Subjects walked along a 10 m walkway at their preferred gait speed and 3DGA data were collected using a VICON(®) 3DGA system. Testing was performed by the same investigator on two separate days within two weeks. Data from 10 trials were averaged and analysed. ANALYSIS The intraclass correlation coefficient (ICC), the standard error of measurement (SEM), minimal detectable change (MDC) and limits of agreement were calculated for kinetic and kinematic data. Bland and Altman plots were applied to gait cycle waveforms. RESULTS Spatio-temporal parameters such as cadence, step length, velocity, step time and step width were highly repeatable generating ICCs of 0.90 and above and low SEM/MDC. Range of joint movement across the gait cycle was generally more reliable than either minimum or maximum values and higher ICCs were obtained for movement in the sagittal plane. For kinematic data the standard error of measurement was low (≤ 5) for the majority of parameters. Transverse plane measurements showed poor reliability with lowest ICCs. ICCs for kinetic data ranged from 0.51 to 0.81. CONCLUSIONS Reliability of 3DGA has been estimated for our gait laboratory. Bland and Altman plots of gait cycle waveforms provide a useful addition to reliability analysis.

Reliability of three-dimensional gait analysis in cervical spondylotic myelopathy

BACKGROUND Gait impairment is one of the primary symptoms of cervical spondylotic myelopathy (CSM). Detailed assessment is possible using three-dimensional gait analysis (3DGA), however the reliability of 3DGA for this population has not been established. The aim of this study was to evaluate the test-retest reliability of temporal-spatial, kinematic and kinetic parameters in a CSM population. METHODS Twelve patients with CSM (mean age 54 years) were consecutively recruited from a neurosurgery clinic. 3DGA was conducted on 2 separate days, less than 1 week apart, using the VICON(®) 250 Motion Analysis. The average of 10 gait cycles was analysed. Reliability was assessed using the one-way random intraclass correlation coefficient (ICC), the standard error of measurement (SEM), and Bland-Altman limits of agreement (LOA). RESULTS Temporal-spatial parameters showed excellent reliability, with ICCs above 0.9 for speed, cadence, stride length, double support time, and step width. ICCs for kinematic parameters ranged from acceptable (0.62, peak knee flexion in stance) to excellent (0.95, total hip sagittal plane motion). The SEM for all kinematic parameters was below 4°, with the exception of peak hip internal rotation (5.8°). Peak values were less reliable than the total range of motion in a plane. The majority of kinetic parameters showed excellent reliability (ICCs>0.85), with the exception of peak medio-lateral ground reaction force (ICC 0.12). CONCLUSIONS This information will enhance the interpretation of gait scores for CSM patients, as an estimate of the change required to exceed measurement error is now available.

Maximum voluntary isometric contraction: investigation of reliability and learning effect.

Maximum Voluntary Isometric Contraction (MVIC) is a standardised, objective and sensitive tool for the measurement of muscle strength. The purpose of this study was to investigate different aspects of reliability of MVIC and to determine if a learning effect existed in a relatively new user of the system. Two clinical investigators participated in the study. The inter‐ and intra‐rater reliability of MVIC of 11 muscle groups was tested on healthy subjects (n=35). Intra‐class correlation co‐efficients (ICCs) were calculated and the statistical methods described by Bland and Altman were applied to the data. ICCs were higher for the more experienced investigator and a learning effect was demonstrated in a relatively new user of the system. Inter‐rater reliability was acceptable but lower than intra‐rater reliability. Upper limb tests generally yielded higher ICCs and lower ranges of error. The ICC was similar regardless of whether the maximum or average of the two values was taken in a single session. Utilising the statistical methods proposed by Bland and Altman allows estimation of the magnitude of error of MVIC and gives additional information to the ICC. These methods may be useful in the training of investigators and in clinical interpretation of MVIC values.

Recovery of the upper limb post ischaemic stroke and the predictive value of the Orpington Prognostic Score

Objective: To document upper limb recovery in stroke patients and investigate whether the Orpington Prognostic Score (OPS) performed within 48 hours of admission to hospital post ischaemic stroke was a predictor of upper limb function at six months and two years. Design: Inception cohort design. Setting: Teaching Hospital. Subjects: One hundred and fourteen patients hospitalized with acute ischaemic stroke were stratified into three groups based on their OPS within 48 hours of admission post stroke and underwent further assessments at two weeks, six months and two years after stroke onset. Main measures: Rivermead Arm Score (RAS), Nine Hole Peg Test (NHPT) and grip strength (GS). Results: Patients with a good OPS and intermediate OPS showed significant recovery in all outcome measures for up to six months post stroke (p < 0.05), while those with a poor OPS at 48 hours showed no significant improvement (p < 0.05). The OPS score at 48 hours was the most highly correlated variable with upper limb outcome at six months (r = -0.728) and at two years (r = -0.712) compared with other variables such as age, class of stroke, sensation, grip strength and RAS. Conclusion: Stroke patients demonstrate differential upper limb recovery patterns which need to be taken in consideration when designing studies that investigate efficacy of rehabilitation, and the OPS is highly correlated with upper limb recovery at six months and two years.

Effectiveness of Conventional Versus Virtual Reality–Based Balance Exercises in Vestibular Rehabilitation for Unilateral Peripheral Vestibular Loss: Results of a Randomized Controlled Trial

OBJECTIVE To compare the effectiveness of virtual reality-based balance exercises to conventional balance exercises during vestibular rehabilitation in patients with unilateral peripheral vestibular loss (UVL). DESIGN Assessor-blind, randomized controlled trial. SETTING Two acute care university teaching hospitals. PARTICIPANTS Patients with UVL (N=71) who had dizziness/vertigo, and gait and balance impairment. INTERVENTIONS Patients with UVL were randomly assigned to receive 6 weeks of either conventional (n=36) or virtual reality-based (n=35) balance exercises during vestibular rehabilitation. The virtual reality-based group received an off-the-shelf virtual reality gaming system for home exercise, and the conventional group received a foam balance mat. Treatment comprised weekly visits to a physiotherapist and a daily home exercise program. MAIN OUTCOME MEASURES The primary outcome was self-preferred gait speed. Secondary outcomes included other gait parameters and tasks, Sensory Organization Test (SOT), dynamic visual acuity, Hospital Anxiety and Depression Scale, Vestibular Rehabilitation Benefits Questionnaire, and Activities Balance Confidence Questionnaire. The subjective experience of vestibular rehabilitation was measured with a questionnaire. RESULTS Both groups improved, but there were no significant differences in gait speed between the groups postintervention (mean difference, -.03m/s; 95% confidence interval [CI], -.09 to .02m/s). There were also no significant differences between the groups in SOT scores (mean difference, .82%; 95% CI, -5.00% to 6.63%) or on any of the other secondary outcomes (P>.05). In both groups, adherence to exercise was high (∼77%), but the virtual reality-based group reported significantly more enjoyment (P=.001), less difficulty with (P=.009) and less tiredness after (P=.03) balance exercises. At 6 months, there were no significant between-group differences in physical outcomes. CONCLUSIONS Virtual reality-based balance exercises performed during vestibular rehabilitation were not superior to conventional balance exercises during vestibular rehabilitation but may provide a more enjoyable method of retraining balance after unilateral peripheral vestibular loss.

An Investigation of Balance Function in Elderly Subjects Who Have and Have Not Fallen

Abstract A study was carried out to investigate whether balance was more impaired in a group of elderly people who had a history of falling than in a group who had no history of falling. Eighty subjects over the age of 65 years participated in the study. The results indicated that balance was more impaired in the group with a history of falling, and they were also more likely to have difficulties with gait.

Reliability of surface electromyography timing parameters in gait in cervical spondylotic myelopathy

The aims of this study were to validate a computerised method to detect muscle activity from surface electromyography (SEMG) signals in gait in patients with cervical spondylotic myelopathy (CSM), and to evaluate the test-retest reliability of the activation times designated by this method. SEMG signals were recorded from rectus femoris (RF), biceps femoris (BF), tibialis anterior (TA), and medial gastrocnemius (MG), during gait in 12 participants with CSM on two separate test days. Four computerised activity detection methods, based on the Teager-Kaiser Energy Operator (TKEO), were applied to a subset of signals and compared to visual interpretation of muscle activation. The most accurate method was then applied to all signals for evaluation of test-retest reliability. A detection method based on a combined slope and amplitude threshold showed the highest agreement (87.5%) with visual interpretation. With respect to reliability, the standard error of measurement (SEM) of the timing of RF, TA and MG between test days was 5.5% stride duration or less, while the SEM of BF was 9.4%. The timing parameters of RF, TA and MG designated by this method were considered sufficiently reliable for use in clinical practice, however the reliability of BF was questionable.