Remotely prescribed and monitored home-based gait-and-balance therapeutic exergaming using augmented reality (AR) glasses: protocol for a clinical feasibility study in people with Parkinson's disease.

BACKGROUND: Clinical guidelines for people with Parkinson's disease (pwPD) stress that, complementary to pharmacological treatment, exercise and physiotherapy should be given a central role in disease management. Adhering to regular exercise of the right type, and with high repetition, remains a challenge for pwPD. Exergaming has the potential to increase adherence through play and personalised interventions, both in clinic and at home. Reality DTx® is an augmented-reality (AR) home-based gait-and-balance exergaming intervention specifically designed for pwPD as an extension of supervised physiotherapy. The primary objective of this study is to evaluate the feasibility and potential efficacy of Reality DTx®. METHODS: Twenty-four pwPD (Hoehn and Yahr stages 2-4) with self-reported gait and/or balance impairments will participate in this study. The study comprises a 6-week waitlist-controlled AR home-based therapeutic gait-and-balance exergaming intervention. Reality DTx® will initially be prescribed remotely for a minimum of 5 days a week for 30 min per day. We will remotely set and adjust the frequency, difficulty, type of games, and/or duration weekly, based on objective and subjective data from the AR glasses and participant, respectively. In addition to the home-based gait-and-balance exergaming intervention, the study comprises three laboratory visits: before the 6-week waitlist period (t0; baseline), before the 6-week intervention period (t1; pre-intervention), and after the 6-week intervention period (t2; post-intervention). The primary study parameters are feasibility (in terms of safety, adherence, and user experience) and potential efficacy for improving gait and balance (using standard clinical gait-and-balance tests and a targeted walking-related fall-risk assessment). Recruitment started in December 2022 and the final post-intervention assessment will be according to planning in July 2023. CONCLUSIONS: This clinical feasibility trial is the first remotely prescribed and monitored home-based AR gait-and-balance exergaming intervention for pwPD. The results in terms of clinical feasibility (i.e. safety, adherence, and user experience) and potential efficacy (gait, balance, and fall-risk outcomes) form the basis for future randomised controlled studies on the effectiveness of home-based AR gait-and-balance exergaming interventions for pwPD. TRIAL REGISTRATION: ClinicalTrials.gov, NCT05605249 . Registered on 4 November 2022.

Visuomotor control of walking in Parkinson's disease: Exploring possible links between conscious movement processing and freezing of gait.

INTRODUCTION: Changes in visual attention have been argued to influence freezing of gait (FOG) in people with Parkinson's Disease (PD). However, the specific visual search patterns of people with FOG pathology (PD + FOG) and potential underlying mechanisms are not well understood. The current study explored visual search behavior in PD + FOG while walking on a pathway featuring environmental features known to exacerbate FOG (e.g., narrow doorway and tripping hazards). Potential underpinning attentional mechanisms were also assessed, such as conscious movement processing. METHODS: Visual search behavior of twelve people with PD + FOG tested in ON-state (Mage = 74.3) and twelve age-matched healthy controls (Mage = 72.5) were analyzed during a complex walking task. The task required participants to step over an obstacle and navigate through a narrow doorway, surrounded by clutter. RESULTS: People with PD + FOG more frequently directed visual attention to ongoing and imminent steps compared to healthy controls (Mdn = 26% vs Mdn = 14%, respectively; p = 0.042). Self-reported conscious movement processing was also significantly higher in people with PD + FOG. The one participant who froze during the walking task fixated the future trip hazard (obstacle, approximately 6 steps ahead) almost exclusively during freezing trials (i.e., 60-100% of the trial). In contrast, during 'non-freeze' trials, this participant increased the duration of fixations towards ongoing and imminent steps. CONCLUSION: Results suggest that people with PD + FOG strongly monitor/control ongoing and immediately upcoming stepping movements. However, prolonged fixations towards threats to future movements might prevent people with PD + FOG from processing the visual information needed to do this, thereby provoke freezing episodes.

The use of electromyography interference pattern analysis to determine muscle force of the deep digital flexor muscle in healthy and laminitic horses.

BACKGROUND: In equine laminitis, the deep digital flexor muscle (DDFM) appears to have increased muscle force, but evidence-based confirmation is lacking. OBJECTIVES: The purpose of this study was to test if the DDFM of laminitic equines has an increased muscle force detectable by needle electromyography interference pattern analysis (IPA). ANIMALS AND METHODS: The control group included six Royal Dutch Sport horses, three Shetland ponies and one Welsh pony [10 healthy, sound adults weighing 411 ± 217 kg (mean ± SD) and aged 10 ± 5 years]. The laminitic group included three Royal Dutch Sport horses, one Friesian, one Haflinger, one Icelandic horse, one Welsh pony, one miniature Appaloosa and six Shetland ponies (14 adults, weight 310 ± 178 kg, aged 13 ± 6 years) with acute/chronic laminitis. The electromyography IPA measurements included firing rate, turns/second (T), amplitude/turn (M) and M/T ratio. Statistical analysis used a general linear model with outcomes transformed to geometric means. RESULTS: The firing rate of the total laminitic group was higher than the total control group. This difference was smaller for the ponies compared to the horses; in the horses, the geometric mean difference of the laminitic group was 1.73 [geometric 95% confidence interval (CI) 1.29-2.32], and in the ponies this value was 1.09 (geometric 95% CI 0.82-1.45). CONCLUSION AND CLINICAL RELEVANCE: In human medicine, an increased firing rate is characteristic of increased muscle force. Thus, the increased firing rate of the DDFM in the context of laminitis suggests an elevated muscle force. However, this seems to be only a partial effect as in this study, the unchanged turns/second and amplitude/turn failed to prove the recruitment of larger motor units with larger amplitude motor unit potentials in laminitic equids.

Clinical Research Abstracts of the British Equine Veterinary Association Congress 2015.

REASONS FOR PERFORMING STUDY: In cases of laminitis, an increased muscle force or contracture of the deep digital flexor muscle (DDFM) is suggested, but evidence-based research is lacking. OBJECTIVES: To test if the DDFM of laminitic equines shows an increased muscle force detectable by needle-EMG including Interference Pattern Analysis (IPA). STUDY DESIGN: Cross-sectional study. METHODS: Three groups consisted of Group 0 (control): 6 Royal Dutch Sport horses, 3 Shetland ponies and one Welsh pony (healthy, sound adults, mean ± s.d. weight 411 ± 217 kg). Group 1: 3 Royal Dutch Sport horses, one Friesian, one Haflinger, one Icelandic horse, 2 Welsh ponies, one miniature Appaloosa and 6 Shetland ponies (adults, mean ± s.d. weight 310 ± 172 kg) suffering from acute or chronic laminitis. EMG measurements including firing frequency (F) and IPA parameters Turns/Second (T), Amplitude/Turn (M) and Ratio M/T (R) were performed. ANOVA was used to analyse data. P values of P<0.05 were considered significant. RESULTS: Mean ± s.d. F of Group 0 and Group 1 was 53 ± 11 and 72 ± 21 Hz, mean ± s.d. T was 112 ± 57 and 106 ± 42, mean ± s.d. M was 284 ± 51 and 254 ± 38 µV and mean ± s.d. R was 0.39 ± 0.17 and 0.42 ± 0.16%, respectively. The firing frequency of Group 1 was significantly higher compared to Group 0 (P = 0.02), whereas other differences were not significant. CONCLUSIONS: In human medicine, an increased firing frequency is a characteristic of increased muscle force [1,2]. Thus, the increased firing frequency of the DDFM in case of laminitis suggests an elevated muscle force. As all parameters show a high variance, a repeated study including a larger test group is advised. Ethical animal research: Data collection from controls was approved by the Animal Welfare Committee of Utrecht University, approval number 2008.III.07.061 and 2013.III.01.012. Clinical cases were privately owned and written owner consent was obtained. SOURCE OF FUNDING: None. Competing interests: None declared.

Determination of equine deep digital flexor muscle volume based on distances between anatomical landmarks.

In equine medicine the use of Botox® is experimental. Dosages are determined from human treatment-protocols and limited numbers of equine studies. Determination of target-muscle volume can be helpful to extrapolate human dosages. The aim of the study was to calculate a formula enabling the estimation of the deep digital flexor muscle (DDFM) volume based on distances between anatomical landmarks. Nineteen cadaveric limbs were collected and distance A (top of olecranon to Os carpi accessorium) and B (circumference of limb) were measured. Converting mathematical formulas, C was calculated: π × (((0.5B)/π)(2)) × A. DDFM volume was determined by water displacement. Linear Regression Analysis was used to analyse data. The line best fitting the observed points was: Ln(volume[ml]) = -1.89 + 0.98 × Ln(value C[cm(3)]). Correlation was highest when natural logarithm was applied to both variables and was 0.97. The calculated formula enables estimating DDFM volume of a living horse. This estimated volume can be useful to apply human Botox® treatment-protocols.

Pressure plate analysis of toe-heel and medio-lateral hoof balance at the walk and trot in sound sport horses.

Empirically, equine distal limb lameness is often linked to hoof imbalance. To objectively quantify dynamic toe-heel and medio-lateral hoof balance of the vertical ground reaction force in sound sport horses, seven Royal Dutch Sport Horses were led at the walk and trot over a dynamically calibrated pressure plate. Forelimb hoof prints were divided into a toe and heel region and a medial and lateral zone. Toe-heel and medio-lateral hoof balance of the vertical ground reaction force were calculated throughout the stance. Toe-heel balance was highly symmetrical between contralateral limbs at both gaits. At the walk, medio-lateral balance of both forelimbs presented higher loading in the lateral part of the hoof throughout the stance. However, at the trot, left medio-lateral balance presented higher loading of the medial part of the hoof at impact, whereas the right limb showed higher loading of the lateral part of the hoof in all horses, and both limbs presented increased lateral loading at the end of the stance. This study provides objective data for toe-heel and medio-lateral hoof balance in sound sport horses.

Microbiological laboratory results from Haiti: June-October 1995.

From June to October 1995, the U.S. Army's 86th Combat Support Hospital was deployed in Haiti in support of the United Nations peacekeeping mission. The hospital's mission was to provide comprehensive health care to United Nations military and civilian personnel in Haiti. The hospital's laboratory, with microbiological and parasitological capability, was a critical asset in light of the infectious disease threats in Haiti. A total of 356 microbiological (5.4%) and 887 parasitological (13.4%) tests were performed, out of a total of 6628 laboratory tests. One finding was the discovery of antibiotic-resistant urinary isolates of Escherichia coli. These were from community-acquired infections and included strains resistant to ampicillin (6/15), trimethoprim+sulfamethoxazole (6/15), and ciprofloxacin (2/15). Ampicillin (8/15) and trimethoprim+sulfamethoxazole (3/15) resistance was also noted in Shigella spp. However, no chloroquine-resistant strains of malaria were encountered. Dengue virus, also mosquito borne, was a major pathogen. Antimicrobial-resistant nosocomial pathogens were also encountered. Deployed laboratories should be able to determine antimicrobial susceptibility and perform microbial identification to guide clinical management, conduct medical surveillance, and detect emerging resistance.